MSC Patran Interface To MSC Nastran Preference Guide Volume 1: Structural Analysis [2017 ed.]

Table of contents :
Chapter 1: Overview......Page 9
1.1 Purpose......Page 10
1.2 MSC Nastran Product Information......Page 12
Chapter 2: Building A Model......Page 13
2.1 Introduction to Building a Model......Page 14
Advanced Output Requests, 481......Page 16
1D - Rod - General Section - CONROD, 139......Page 17
Fatigue Parameters Subform, 370......Page 18
1D - Beam - Lumped Section (CBEAM/PBCOMP), 128......Page 19
Adaptive Mesh Post-Processing, 476......Page 20
Define Fatigue Load Sequences, 488......Page 21
Crack (VCCT), 271......Page 22
Initial Conditions......Page 23
Element Properties......Page 24
Materials......Page 25
Elements and Properties......Page 26
Solution Controls......Page 27
2.3 Adaptive (p-Element) Analysis with the MSC Nastran Preference......Page 28
Element Creation......Page 29
Element and p-Formulation Properties......Page 30
Loads and Boundary Conditions......Page 31
Analysis Definition......Page 32
Results Import and Postprocessing......Page 33
Potential Pitfalls......Page 34
Adaptive Analysis of Existing Models......Page 35
2.4 Coordinate Frames......Page 36
Nodes......Page 37
Elements......Page 38
Multi-point Constraints......Page 40
MPC Types......Page 42
Structural......Page 46
Superelements......Page 62
Select Boundary Nodes......Page 65
2.6 Material Library......Page 66
Materials Application Form......Page 67
Material Input Properties Form......Page 69
Material Constitutive Models......Page 70
Linear Elastic......Page 81
Nonlinear Elastic......Page 83
Hyperelastic......Page 84
Elastoplastic......Page 89
Failure......Page 92
Failure 1, Failure 2, Failure 3......Page 93
Creep......Page 96
Hypoelastic......Page 97
User Defined......Page 98
Viscoelastic......Page 99
Stress-Life (SN) and Strain Life (eN), Spot Weld (Top and Bottom Sheet), Seam Weld (Stiff and Flexible)......Page 100
Cohesive......Page 103
Composite......Page 107
Element Properties Form......Page 109
0D - Coupled Point Mass (CONM1)......Page 116
0D - Grounded Scalar Mass (CMASS1)......Page 117
0D - Lumped Point Mass (CONM2)......Page 118
0D - Grounded Scalar Spring (CELAS1/CELAS1D)......Page 119
0D - Grounded Scalar Damper (CDAMP1/CDAMP1D)......Page 120
0D - Grounded Bush (CBUSH/PBUSH)......Page 121
1D - Beam - General Section (CBAR) - Standard Formulation......Page 122
1D - Beam - General Section (CBEAM) - P-Formulation......Page 128
1D - Beam - General Section (CBAR) - Linear/Cubic Closed Section......Page 130
1D - Beam - General Section (CBAR) - Linear-Shear......Page 131
1D - Beam - Curved with General Section (CBEND)......Page 132
1D - Beam - Curved with Pipe Section (CBEND)......Page 134
1D - Beam - Lumped Section (CBEAM/PBCOMP)......Page 136
1D - Beam - Tapered Section (CBEAM) - Standard Formulation......Page 138
1D - Beam - Tapered Section (CBEAM) - P-Formulation......Page 140
1D - Beam - General Section (CBEAM) - Standard Formulation......Page 141
1D - Beam - General Section (CBEAM) - Linear/Cubic Closed Section......Page 143
1D - Beam - General Section (CBEAM) - Linear/Cubic Open Section......Page 144
1D - Beam - General Section (CBEAM) - Linear-Shear......Page 145
1D - Rod - General Section (CROD) - Standard Formulation......Page 146
1D - Rod - General Section - CONROD......Page 147
1D - Rod - Pipe Section (CTUBE)......Page 148
1D - Spring (CELAS1)......Page 149
1D - Damper - Scalar (CDAMP1)......Page 150
1D - Damper - Viscous (CVISC)......Page 151
1D - Gap - Adaptive / Non Adaptive (CGAP)......Page 152
1D - Scalar Mass (CMASS1)......Page 154
1D - PLOTEL......Page 155
1D - Bush (CBUSH)......Page 156
1D- Bush (CBUSH2D/PBUSH2D)......Page 158
1D - Spot Weld Connector (CWELD)......Page 160
1D - Fastener Connector (CFAST)......Page 161
2D - Shell - Thin - Homogeneous - Standard Formulation......Page 164
2D - Shell - Homogeneous - Revised Formulation......Page 167
2D - Shell - Thin - Homogeneous - P-Formulation......Page 169
2D - Shell - Thin - Homogeneous - Linear Discrete Kirchhoff......Page 171
2D - Shell - Thin - Laminate Plate- Standard Formulation......Page 173
2D - Shell - Thin - Laminate - Revised Formulation......Page 175
2D - Shell - Thin - Equivalent Section - Standard Formulation......Page 177
2D - Shell - Thin - Equivalent Section - Revised Formulation......Page 179
2D - Shell - Thin - Equivalent Section - P-Formulation......Page 181
2D - Shell - Thick - Standard Formulation......Page 183
2D - Shell - Thick - Reduced Integration......Page 185
2D - Shell - Field Point Mesh......Page 187
2D - Bending Panel - Standard Formulation......Page 188
2D - Bending Panel - Revised Formulation......Page 190
2D - Bending Panel - P-Formulation......Page 192
2D - 2D Solid - Plane Strain - Standard Formulation......Page 194
2D - 2D Solid - Plane Strain - Reduced Integration......Page 196
2D - 2D Solid - Plane Strain - Revised Formulation......Page 197
2D - 2D Solid - Plane Strain - P-Formulation......Page 198
2D - 2D Solid - Plane Strain - Hyperelastic Formulation......Page 200
2D - Plane Strain - Laminated Composite......Page 201
2D - 2D Solid - Plane Strain - Incompressible......Page 202
2D - 2D Solid - Plane Strain - Interface......Page 203
2D - 2D Solid - Plane Stress - Standard Formulation......Page 204
2D - 2D Solid - Plane Stress- Reduced Integration......Page 206
2D - 2D Solid - Plane Stress - Interface......Page 207
2D - 2D Solid - Axisymmetric - Standard Formulation......Page 208
2D - 2D Solid - Axisymmetric - Reduced Integration......Page 210
2D - 2D Solid - Axisymmetric - Twist......Page 211
2D - 2D Solid - Axisymmetric - Hyperelastic Formulation......Page 212
2D - 2D Solid - Axisymmetric - Laminated Composite......Page 213
2D - 2D Solid - Axisymmetric - PLPLANE......Page 214
2D - 2D Solid - Axisymmetric - Incompressible......Page 215
2D - 2D Solid - Axisymmetric - Interface......Page 216
2D - 2D Solid - Acoustic Infinite......Page 217
2D - Membrane - Standard Formulation......Page 218
2D - Membrane - Revised Formulation......Page 220
2D - Membrane - P-Formulation......Page 221
2D - Shear Panel......Page 223
3D - Solid - Homogeneous - Standard Formulation......Page 225
3D - Solid - Homogeneous - Reduced Integration......Page 227
3D - Solid - Homogeneous - P-Formulation......Page 228
3D - Solid - Homogeneous - Hyperelastic......Page 230
3D - Solid Shell - Homogeneous - Standard Formulation......Page 231
3D - Solid - Homogeneous - Incompressible......Page 232
3D - Solid - Laminate......Page 233
3D - Solid - Interface......Page 234
3D - Body Pair- Geometric......Page 235
3D - Body Pair- Physical......Page 237
Cross Section Definition......Page 238
Create Action......Page 239
Supplied Functions......Page 241
Cross Section Orientation......Page 242
Stiffened Cylinder Example......Page 246
Loads & Boundary Conditions Form......Page 248
Static......Page 252
Time Dependent......Page 255
Displacement / Velocty / Acceleration......Page 256
Force......Page 259
Pressure......Page 260
Temperature......Page 262
Inertial Load......Page 265
Initial Velocity......Page 266
Distributed Load......Page 267
CID Distributed Load......Page 268
Contact......Page 269
Total Load......Page 278
Description......Page 279
2.10 Load Cases......Page 283
2.11 Defining Contact Regions......Page 284
Contact......Page 286
2.12 Rotor Dynamics......Page 288
Rotor Dynamics Form......Page 289
Spin Profile Form......Page 292
Spin History Form......Page 293
Unbalance Form......Page 294
Unbalance Properties Form......Page 296
Chapter 3: Running an Analysis......Page 299
3.1 Review of the Analysis Form......Page 300
Analysis Form......Page 301
Interactive......Page 303
Overview of Analysis Job Definition and Submittal......Page 304
3.2 Translation Parameters......Page 306
This option is OFF by default. This option can be turned ON to write continuation markers for Bulk Data entries.......Page 307
Prompts you for the filename of the include file.......Page 308
Numbering Options......Page 309
Select File......Page 312
3.3 Solution Types......Page 313
Selects Solution Sequence 700.......Page 314
Brings up a solution-type-dependent subordinate form that allows you to specify parameters which apply to the complete solution.......Page 315
600......Page 316
700......Page 317
3.4 Direct Text Input......Page 318
Linear Static......Page 320
Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.......Page 322
Nonlinear Static......Page 323
On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.......Page 325
2......Page 326
Normal Modes......Page 327
48......Page 328
On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.......Page 329
Defines the degree-of-freedom component at the Normalization Point to be used. This can only be selected if Normalization Method is set to Point. This parameter cannot be specified if Extraction Method is set to Lanczos. This is the C field on the EI.........Page 331
Buckling......Page 334
Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.......Page 335
On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.......Page 336
Indicates what type of eigenvalue normalization is to be done. This parameter can take one of two settings: Maximum or Point. This parameter cannot be specified if Extraction Method is set to Lanczos. This is the NORM field on the EIGB entry.......Page 338
Defines the degree-of-freedom component at the Normalization Point to be used. This, too, can only be selected if Normalization Method is set to Point. This parameter cannot be specified if Extraction Method is set to Lanczos. This is the C field on .........Page 339
Complex Eigenvalue......Page 340
Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.......Page 341
On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.......Page 342
Indicates what type of eigenvalue normalization is to be done. This parameter can take one of two settings: Maximum or Point. This is the NORM field on the EIGC entry.......Page 344
Defines the degree-of-freedom component at the Normalization Point to be used. This can only be selected if Extraction Method is set to Inverse Power or Determinate. This is the C field on the EIGC Bulk Data entry.......Page 345
Frequency Response......Page 346
Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.......Page 347
On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.......Page 348
Transient Response......Page 349
Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.......Page 350
On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.......Page 351
Nonlinear Transient......Page 352
Implicit Nonlinear......Page 354
Specifies the solver to be used in numerically inverting the system matrix of linear equilibrium equations.......Page 356
Contact Parameters Subform......Page 358
Restart Parameters Subform......Page 369
Advanced Job Control Subform (SOL 600)......Page 371
Domain Decomposition is used to partition the model into seperate parts (domains) for parallel processing. The Method used to do this is named Domain Decomposition Method (DDM). This form designates that domain decomposition be done manually, semi-au.........Page 372
Click Create to create Domain Information spreadsheet rows. After doing this the number of rows will equal the value of Number of Domains in the form. If Decomposition Method is set to Manual, the previously created group names will be selectable in .........Page 374
User Defined Services......Page 375
MSC_SDK_PATH and User Source File fields appear on the simple form and show the current settings of the variables, whether they are defined or not. If the variables are defined then the textboxes show the (the actual settings of the variables).........Page 376
Optional input data (integer, real, characters) required for a user subroutine. Clicking on the cell will open a spreadsheet where you can enter the data.......Page 377
Fatigue Parameters Subform......Page 378
DDAM......Page 386
DDAM in Patran......Page 387
Indicates that MSC Nastran will define grid point normals for a Faceted Shell Surface based on the Tolerance Angle. This data appears on a PARAM, SNORM entry.......Page 389
On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.......Page 390
Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.......Page 391
Sol700 Parameters Subform......Page 392
.......Page 393
Hourglass Setting Subform......Page 394
.......Page 395
Merge Rigid Material Subform......Page 396
.......Page 397
Dynamic Relaxation for Restart Subform......Page 398
Click the checkbox to specify that convergence control is to be automatic using the Papadrakakis method.......Page 399
Damping Per Property Subform......Page 400
This subordinate form appears when Rigid Body Switch and Merge button is selected on the Sol700 Parameters and Extra Data form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as:......Page 401
.......Page 402
Define Set of Parts to be Switched Subform......Page 404
Define Inertial Properties of Rigid Body Subform......Page 406
Eulerian Parameters Subform......Page 407
This subordinate form appears when SPH Control Parameters (SPH refers to smooth “particle hydrodynamics”) button is selected on the Sol700 Parameters and Extra Data form of either Explicit Nonlinear or other structural Solution Type where Sol700 .........Page 410
.......Page 411
Results Output Format......Page 413
ADAMS Preparation......Page 415
3.6 Select Superelements......Page 417
3.7 Subcases......Page 419
Deleting Subcases......Page 420
Editing Subcases......Page 421
Linear Static Subcase Parameters......Page 422
Nonlinear Static Subcase Parameters......Page 424
Arc-Length Method Parameters......Page 426
Nonlinear Transient Subcase Parameters......Page 427
Normal Modes Subcase Parameters......Page 429
Complex Eigenvalue Subcase Parameters......Page 431
Transient Response Subcase Parameters......Page 433
Frequency Response Subcase Parameters......Page 436
Implicit Nonlinear Subcase Parameters......Page 443
Static Subcase Parameters for Implicit Nonlinear Solution Type......Page 444
Implicit Nonlinear Buckling Subcase Parameters......Page 445
Implicit Nonlinear Transient Dynamic Subcase Parameters......Page 446
Implicit Nonlinear Creep Subcase Parameters......Page 448
Implicit Nonlinear Body Approach Subcase Parameters......Page 449
Implicit Nonlinear Complex Eigenvalue Subcase Parameters......Page 450
Load Increment Parameters......Page 451
Iteration Parameters......Page 459
Contact Table......Page 464
Advanced Parameters Subform......Page 467
Contact Boundary Subform......Page 470
Defines groups of elements to be active or deactive for the subcase.......Page 471
Defines parameter values for modeling break squeal. (SOL 400 only).......Page 472
Solvers/Options......Page 473
DDAM Subcase Parameters......Page 476
Explicit Nonlinear Subcase Parameters......Page 478
Contact Table......Page 482
Additional Contact Data......Page 483
Additional Information......Page 484
3.9 Output Requests......Page 486
Basic Output Requests......Page 487
Advanced Output Requests......Page 489
Requests nodal accelerations.......Page 490
Requests the form and type of nonlinear element stress output.......Page 491
Edit Output Requests Form......Page 499
or_value......Page 501
x......Page 502
25......Page 503
Subcases Direct Text Input......Page 504
SOL 600 Output Requests......Page 505
DDAM Output Requests......Page 511
Mode by Mode Output......Page 512
3.10 Select Explicit MPCs.........Page 516
CONROD, PBAR, PBARL, PBCOMP, PBEAM, PBEAML, PBEND, PCOMP, PCONEAX. PRAC2D, PROD, PSHEAR, PSHELL, PTUBE......Page 517
3.12 Select NSM Properties.........Page 522
3.13 Subcase Select......Page 523
Select Steps for New Subcases (Step Creation)......Page 525
Define Fatigue Load Sequences......Page 527
Fatigue Load Sequences for time domain SOLs 101, 103, & 111......Page 529
Fatigue Load Sequences for SOLs 108 & 111(frequency response)......Page 531
3.14 Restart Parameters......Page 539
3.15 Optimize......Page 545
3.16 Toptomize......Page 547
Objectives & Constraints......Page 549
Optimization Control......Page 550
Design Domain......Page 553
Postprocessing......Page 557
Scenario 2......Page 558
Miscellaneous......Page 559
Analysis Form......Page 560
Select Modal Results .DBALL......Page 561
Loading Form......Page 563
Create a Field Form......Page 565
Output Selection Form......Page 566
Define Frequencies Form......Page 567
Chapter 4: Read Results......Page 569
4.1 Accessing Results......Page 570
Output2 Formats......Page 571
MASTER Formats......Page 572
3dplot Formats......Page 574
OUTPUT2......Page 575
Defining Translation Parameters for DDAM (SOL 187)......Page 576
XDB and HDF5......Page 577
MASTER......Page 578
T16/T19......Page 581
Results......Page 582
Global Variables......Page 588
XY Plots......Page 589
Model Data......Page 590
4.3 Supported T16/T19 Results Quantities......Page 591
Nodal Results......Page 596
Elemental Results......Page 603
4.5 Supported 3dplot Results Quantities......Page 623
4.6 Supported HDF5 Result Quantities......Page 625
Chapter 5: Read Input File......Page 627
5.1 Review of Read Input File Form......Page 628
Read Input File Form......Page 629
Entity Selection Form......Page 631
Define Offsets Form......Page 634
Summary Data Form......Page 636
Reject Card Form......Page 638
Coordinate Systems......Page 639
Referential Integrity......Page 640
Elements and Element Properties......Page 641
BAROR and BEAMOR Definitions......Page 644
Set Name Extensions......Page 645
Materials......Page 646
Load Sets......Page 647
TABLES......Page 649
Fatigue Related Entries......Page 650
Conflict Resolution for Entities Identified by Names......Page 651
Chapter 6: Delete......Page 653
6.1 Review of Delete Form......Page 654
6.2 Deleting an MSC Nastran Job......Page 655
Chapter 7: Files......Page 657
7.1 Files......Page 658
Chapter 8: Errors/Warnings......Page 661
8.1 Errors/Warnings......Page 662
Ap. A: Preference Configuration and Implementation......Page 663
1.1 Software Components in Patran MSC Nastran......Page 664
1.2 Patran MSC Nastran Preference Components......Page 665
1.3 Configuring the Patran MSC Nastran Execute File......Page 668
Index......Page 669

Citation preview

Patran 2017 Interface To MSC Nastran Preference Guide Volume 1: Structural Analysis

Main Index

Corporate

MSC Software Corporation 4675 MacArthur Court, Suite 900 Newport Beach, CA 92660 Telephone: (714) 540-8900 Toll Free Number: 1 855 672 7638 Email: [email protected]

Japan

MSC Software Japan Ltd. Shinjuku First West 8F 23-7 Nishi Shinjuku 1-Chome, Shinjuku-Ku Tokyo 160-0023, JAPAN Telephone: (81) (3)-6911-1200 Email: [email protected]

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Asia-Pacific

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Worldwide Web www.mscsoftware.com

Support http://www.mscsoftware.com/Contents/Services/Technical-Support/Contact-Technical-Support.aspx

Disclaimer This documentation, as well as the software described in it, is furnished under license and may be used only in accordance with the terms of such license. MSC Software Corporation reserves the right to make changes in specifications and other information contained in this document without prior notice. The concepts, methods, and examples presented in this text are for illustrative and educational purposes only, and are not intended to be exhaustive or to apply to any particular engineering problem or design. MSC Software Corporation assumes no liability or responsibility to any person or company for direct or indirect damages resulting from the use of any information contained herein. User Documentation: Copyright 2017 MSC Software Corporation. All Rights Reserved. This notice shall be marked on any reproduction of this documentation, in whole or in part. Any reproduction or distribution of this document, in whole or in part, without the prior written consent of MSC Software Corporation is prohibited. This software may contain certain third-party software that is protected by copyright and licensed from MSC Software suppliers. Additional terms and conditions and/or notices may apply for certain third party software. Such additional third party software terms and conditions and/or notices may be set forth in documentation and/or at http://www.mscsoftware.com/thirdpartysoftware (or successor website designated by MSC from time to time). The MSC Software Logo, MSC, MSC Nastran, Marc, Patran, Dytran, and Laminate Modeler are trademarks or registered trademarks of MSC Software Corporation in the United States and/or other countries. NASTRAN is a registered trademark of NASA. PAM-CRASH is a trademark or registered trademark of ESI Group. SAMCEF is a trademark or registered trademark of Samtech SA. LS-DYNA is a trademark or registered trademark of Livermore Software Technology Corporation. ANSYS is a registered trademark of SAS IP, Inc., a wholly owned subsidiary of ANSYS Inc. ACIS is a registered trademark of Spatial Technology, Inc. ABAQUS, and CATIA are registered trademark of Dassault Systemes, SA. FLEXlm and FlexNet Publisher are trademarks or registered trademarks of Flexera Software. PostScript is a registered trademark of Adobe Systems, Inc. PTC and Pro/ENGINEER are trademarks or registered trademarks of Parametric Technology Corporation or its subsidiaries in the United States and/or other countries. Unigraphics, Parasolid and I-DEAS are registered trademarks of Siemens Product Lifecycle Management, Inc. All other brand names, product names or trademarks belong to their respective owners.

P3:V2017:Z:INT-NA:Z:DC-USR-PDF

Main Index

Contents Patran Interface to MSC Nastran Preference Guide

Patra MSC ence

1

Overview Purpose

2

MSC Nastran Product Information

2

4

Building A Model Introduction to Building a Model

6

Currently Supported MSC Nastran Input Options MSC Nastran Implicit Nonlinear (SOL 400/600) 15 MSC Nastran Explicit Nonlinear (SOL 700) 17

8

Adaptive (p-Element) Analysis with the MSC Nastran Preference Coordinate Frames Finite Elements 29 Nodes 29 Elements 30 Multi-point Constraints Superelements 54

28

32

Material Library 58 Materials Application Form 59 Material Input Properties Form 61 Material Constitutive Models 62 Element Properties 101 Element Properties Form 101 0D Element Properties 108 1D Element Properties 114 2D Element Properties 156 3D Element Properties 217 3DBeam Modeling 230 Cross Section Definition 230 Cross Section Orientation 234

Main Index

20

iv Patran Interface to MSC Nastran Preference Guide

Cross Section End Offsets Stiffened Cylinder Example

238 238

Loads and Boundary Conditions Loads & Boundary Conditions Form Object Tables 248 Load Cases

240 240

275

Defining Contact Regions Contact 278

276

Rotor Dynamics 280 Rotor Dynamics Form 281 Spin Profile Form 284 Spin History Form 285 Unbalance Form 286 Unbalance Properties Form 288

3

Running an Analysis Review of the Analysis Form 292 Analysis Form 293 Overview of Analysis Job Definition and Submittal Translation Parameters 298 External Superelement Specifications Numbering Options 301 Select File 304 Solution Types Direct Text Input

305 310

Solution Parameters 312 Linear Static 312 Nonlinear Static 315 Normal Modes 319 Buckling 326 Complex Eigenvalue 332 Frequency Response 338 Transient Response 341 Nonlinear Transient 344 Implicit Nonlinear 346 DDAM 378 Explicit Nonlinear 383

Main Index

301

296

CONTENTS v

ADAMS Preparation

407

Select Superelements Subcases 411 Deleting Subcases Editing Subcases

409

412 413

Subcase Parameters 414 Linear Static Subcase Parameters 414 Nonlinear Static Subcase Parameters 416 Arc-Length Method Parameters 418 Nonlinear Transient Subcase Parameters 419 Normal Modes Subcase Parameters 421 Complex Eigenvalue Subcase Parameters 423 Transient Response Subcase Parameters 425 Frequency Response Subcase Parameters 428 Implicit Nonlinear Subcase Parameters 435 Solvers/Options 465 DDAM Subcase Parameters 468 Explicit Nonlinear Subcase Parameters 470 Adaptive Mesh Post-Processing 476 Output Requests 478 Basic Output Requests 479 Advanced Output Requests 481 Edit Output Requests Form 491 Default Output Request Information 496 SOL 600 Output Requests 497 DDAM Output Requests 503 Select Explicit MPCs...

493

508

Non-Structural Mass Properties Select NSM Properties...

509

514

Subcase Select 515 Select Steps for New Subcases (Step Creation) Define Fatigue Load Sequences 519 Restart Parameters Optimize Toptomize

Main Index

537 539

531

517

vi Patran Interface to MSC Nastran Preference Guide

Interactive Analysis 550 Analysis Form 552 Select Modal Results .DBALL 553 Loading Form 555 Create a Field Form 557 Output Selection Form 558 Define Frequencies Form 559

4

Read Results Accessing Results 562 Results File Formats 563 Translation Parameters 567 Supported OUTPUT2 Result and Model Quantities Supported T16/T19 Results Quantities

583

Supported MSC.Access Result Quantities Supported 3dplot Results Quantities Supported HDF5 Result Quantities

5

615 617

Read Input File Review of Read Input File Form Read Input File Form 621 Entity Selection Form 623 Define Offsets Form 626 Selection of Input File 628 Summary Data Form 628 Reject Card Form 630

620

Data Translated from the NASTRAN Input File Coordinate Systems 631 Grids and SPOINTs 632 Elements and Element Properties 633 Materials 638 MPCs 639 Load Sets 639 TABLES 641 Fatigue Related Entries 642 Conflict Resolution

Main Index

588

643

631

574

CONTENTS vii

Conflict Resolution for Entities Identified by IDs 643 Conflict Resolution for Entities Identified by Names 643

6

Delete Review of Delete Form

646

Deleting an MSC Nastran Job

7

Files Files

8

650

Errors/Warnings Errors/Warnings

A

647

654

Preference Configuration and Implementation Software Components in Patran MSC Nastran

656

Patran MSC Nastran Preference Components

657

Configuring the Patran MSC Nastran Execute File

Index

Main Index

661

660

viii Patran Interface to MSC Nastran Preference Guide

Main Index

Chapter 1: Overview Patran Interface to MSC Nastran Preference Guide

1

Main Index

Overview



Purpose

2



MSC Nastran Product Information

4

2

Patran Interface to MSC Nastran Preference Guide Purpose

1.1

Purpose Patran is an analysis software system developed and maintained by MSC Software Corporation. The core of the system is a finite element analysis pre and postprocessor. Several optional products are available including; advanced postprocessing programs, tightly coupled solvers, and interfaces to third party solvers. The amount of information that needs to be conveyed in the MSC Nastran Input file for an analysis is extensive for even a modest size model. The amount of information and the complexity of most models makes it virtually impossible to generate the MSC Nastran Input file with a text editor alone. Patran provides a graphical user interface, an extensive line of model building tools that you can use to construct and view your model. The Patran MSC Nastran interface provides a communication link between Patran and MSC Nastran. It also provides for the customization of certain features in Patran. The interface is a fully integrated part of the Patran system. MSC Nastran is a powerful tool to provide solutions for static and dynamic structural, acoustics, and heat transfer analysis. Structural analysis may be linear or nonlinear and dynamic systems may be solved using either modal based methods or direct transient implicit or explicit formulations. The MSC Nastran Preference guide is divided into three volumes loosely based upon the type of physics and the MSC Nastran solution sequences. This manual is focused on classic structural solution sequences and explicit dynamics (SOL 700). The second volume is focused on heat transfer (SOL 101, SOL 153 and SOL 159), and the third volume is focused on implicit nonlinear analysis (SOL 400). Note that SOL 400 can be used for linear structural, analysis, heat transfer and thermal-mechanically couple analysis as well. Please refer to the correct MSC Nastran preference volume. When invoking Patran you control the interface and the Solution Sequence by choosing the preference. The choice of preferences include: • MSC Nastran Structure • MSC Nastran Thermal • MSC Nastran Aeroelasticity • MSC Nastran Implicit Nonlinear (SOL 400) • MSC Nastran Explicit Nonlinear (SOL 700)

Selecting MSC Nastran as the analysis code preference in Patran, activates the customization process. These customizations ensure that sufficient and appropriate data is generated for the Patran MSC Nastran interface. Specifically, the Patran forms in these main areas are modified: • Materials • Element Properties • Finite Elements/MPCs and Meshing • Loads and Boundary Conditions

Main Index

Chapter 1: Overview 3 Purpose

• Analysis Forms

More information on these topics is contained in Preference Configuration and Implementation (App. A).

Main Index

4

Patran Interface to MSC Nastran Preference Guide MSC Nastran Product Information

1.2

MSC Nastran Product Information MSC Nastran is a general-purpose finite element computer program for engineering analyses. It is developed, supported, and maintained by MSC Software Corporation, 4675 MacArthur Ct, Newport Beach, CA. 92660, (714) 540-8900. See the MSC Nastran Reference Manual, for a general description of MSC Nastran’s capabilities.

Main Index

Chapter 2: Building A Model Patran Interface to MSC Nastran Preference Guide

2

Main Index

Building A Model 

Introduction to Building a Model

6



Currently Supported MSC Nastran Input Options



Adaptive (p-Element) Analysis with the MSC Nastran Preference



Coordinate Frames



Finite Elements

29



Material Library

58



Element Properties

101



3DBeam Modeling

230



Loads and Boundary Conditions



Load Cases



Defining Contact Regions



Rotor Dynamics

28

275

280

276

240

8 20

6

Patran Interface to MSC Nastran Preference Guide Introduction to Building a Model

2.1

Introduction to Building a Model There are many aspects to building a finite element analysis model. In several cases, the forms used to create the finite element data are dependent on the selected analysis code and analysis type. Other parts of the model are created using standard forms. The Analysis option on the Preferences menu brings up a form where the user can select the analysis code (e.g., MSC Nastran) and analysis type (e.g., Structural).

The analysis code may be changed at any time during model creation.This is especially useful if the model is to be used for different analyses in different analysis codes. As much data as possible will be converted if the analysis code is changed after the modeling process has begun. The analysis option defines what will be presented to the user in several areas during the subsequent modeling steps. These areas include the material and element libraries, including multi-point constraints, the applicable loads and boundary conditions, and the analysis forms. The selected Analysis Type may also affect the

Main Index

Chapter 2: Building A Model 7 Introduction to Building a Model

allowable selections in these same areas. For more details, see The Analysis Form (Ch. 2) in the Patran Reference Manual.

Entry

Main Index

Description

Analysis Code

To use the Patran MSC Nastran Application Preference, this should be set to MSC Nastran.

Analysis Type

The currently supported Analysis Type for Patran MSC Nastran are Structural, Thermal, Implicit Nonlinear, Explicit Nonlinear, and Aeroelasticity.

Input File Suffix

Indicates the file suffix used in creating file names for MSC Nastran input files.

Output File Suffix

Indicates the file suffix used in creating file names for MSC Nastran output files.

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Patran Interface to MSC Nastran Preference Guide Currently Supported MSC Nastran Input Options

2.2

Currently Supported MSC Nastran Input Options The following tables summarize all the various MSC Nastran commands supported by the Patran MSC Nastran Application Preference. The tables indicate where to find more information in this manual on how the commands are supported Table 2-1. Supported File Management Commands Entry ASSIGN

Description An ASSIGN command is used to assign a particular name (job name + user specified MSC Nastran results suffix) to the MSC Nastran OUTPUT2 file to be created during the analysis.

Table 2-2. Supported Executive Control Commands Entry

Pages

ECHO

Solution Parameters, 312

SOL

Solution Types, 305

TIME

Solution Parameters, 312

Table 2-3. Supported Case Control Commands Entry ACCELERATION

Frequency Response, 338, Transient Response, 341

ACFPMRESULTS

Advanced Output Requests, 481

ACPOWER

Advanced Output Requests, 481

ADACT

Analysis Definition, 24, Subcase Parameters, 414

ADAPT

Element and p-Formulation Properties, 22, 3D - Solid - Homogeneous - P-Formulation, 220

DATAREC

Analysis Definition, 24

DISPLACEMENT

Advanced Output Requests, 481

ELSDCON

Advanced Output Requests, 481

ESE

Advanced Output Requests, 481

FATIGUE

Advanced Output Requests, 481

FORCE

Advanced Output Requests, 481

FREQUENCY

Frequency Response, 338

GPSTRESS

Advanced Output Requests, 481

INTENSITY

Advanced Output Requests, 481

MAXLINES

Solution Parameters, 312

MPCFORCES

Main Index

Pages

Advanced Output Requests, 481

Chapter 2: Building A Model 9 Currently Supported MSC Nastran Input Options

Table 2-3. Supported Case Control Commands Entry

Pages

OLOAD

Advanced Output Requests, 481

SPCFORCES

Advanced Output Requests, 481

STRAIN

Advanced Output Requests, 481

Table 2-4. Supported Bulk Data Entries Entry ADAPT BEGIN AFPM BEGIN BULK SUPER

3D - Solid - Homogeneous - P-Formulation, 220 2D - Shell - Field Point Mesh, 179 Select Superelements, 409

CACINF3

2D - 2D Solid - Acoustic Infinite, 209

CACINF4

2D - 2D Solid - Acoustic Infinite, 209

CBARAO

1D Element Properties, 114

CBAR

1D Element Properties, 114

CBEAM

1D - Beam - Lumped Section (CBEAM/PBCOMP), 128, 1D - Beam Tapered Section (CBEAM) - Standard Formulation, 130

CBEND

1D - Beam - Curved with General Section (CBEND), 124, 1D - Beam Curved with Pipe Section (CBEND), 126

CDAMP1

0D - Grounded Scalar Damper (CDAMP1/CDAMP1D), 112

CDAMP2

Entity Selection Form, 623, Elements and Element Properties, 633

CELAS1

0D - Grounded Scalar Spring (CELAS1/CELAS1D), 111

CELAS2

Entity Selection Form, 623, Elements and Element Properties, 633

CGAP CHEXA

1D - Gap - Adaptive / Non Adaptive (CGAP), 144 3D - Solid - Homogeneous - Standard Formulation, 217

CIFQUAD

2D - 2D Solid - Plane Strain - Interface, 195

CIFQDX

2D - 2D Solid - Axisymmetric - Interface, 208

CIFHEX

3D - Solid - Interface, 226

CIFPENT

3D - Solid - Interface, 226

CMASS1

1D - Scalar Mass (CMASS1), 146, 0D - Grounded Scalar Mass (CMASS1), 109

CMASS2

Entity Selection Form, 623, Elements and Element Properties, 633

CONM1

0D - Coupled Point Mass (CONM1), 108

CONM2

0D - Lumped Point Mass (CONM2), 110

CONROD

Main Index

Pages

1D - Rod - General Section - CONROD, 139

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Patran Interface to MSC Nastran Preference Guide Currently Supported MSC Nastran Input Options

Table 2-4. Supported Bulk Data Entries Entry CPENTA

3D - Solid - Homogeneous - Standard Formulation, 217

CQUAD4

2D Element Properties, 156,

CQUAD8

2D Element Properties, 156,

CQUADR

2D - Shell - Homogeneous - Revised Formulation, 159, 2D - Shell - Thin - Laminate - Revised Formulation, 167, 2D - Shell - Thin - Equivalent Section - Revised Formulation, 171, 2D - Bending Panel - Revised Formulation, 182, 2D - Membrane - Revised Formulation, 212

CROD CSHEAR

1D - Rod - General Section (CROD) - Standard Formulation, 138 2D - Shear Panel, 215

CTETRA

3D - Solid - Homogeneous - Standard Formulation, 217

CTRIAX6

2D - 2D Solid - Axisymmetric - Standard Formulation, 200

CTUBE

1D - Rod - Pipe Section (CTUBE), 140

CVISC

1D - Damper - Viscous (CVISC), 143

DCONST

Objectives & Constraints, 541

DOPTPRM

Optimize, 537, Toptomize, 539

DPHASE

Object Tables, 248

DRESP1/2

Objectives & Constraints, 541

DTI, SETREE DTI,UNITS DYNRED

Select Superelements, 409 Fatigue Parameters Subform, 370 Dynamic Reduction Parameters, 324

EIGB

Buckling Eigenvalue Extraction, 329, Real Eigenvalue Extraction, 322

EIGC

Complex Eigenvalue Extraction, 335

EIGR

Real Eigenvalue Extraction, 322

EIGRL

Real Eigenvalue Extraction, 322

EXTSEOUT

External Superelement Specifications, 301

FEFACE

Element Creation, 21

FEEDGE

Element Creation, 21

FORCE

Force, 251

FREQ1

Frequency Response, 338

FTGDEF

Main Index

Pages

Output Request Form Options, 484

FTGEVNT

Define Fatigue Load Sequences, 519

FTGLOAD

Define Fatigue Load Sequences, 519

FTGPARM

Fatigue Parameters Subform, 370

Chapter 2: Building A Model 11 Currently Supported MSC Nastran Input Options

Table 2-4. Supported Bulk Data Entries Entry FTGSEQ

Define Fatigue Load Sequences, 519

GMBC

Displacement / Velocty / Acceleration, 248

GRAV

Inertial Load, 257

MOMENT

Force, 251

MAT1

Linear Elastic, 73

MAT2

Linear Elastic, 73

MAT3

Linear Elastic, 73

MAT8

Linear Elastic, 73

MAT9

Linear Elastic, 73

MATFTG

Stress-Life (SN) and Strain Life (eN), Spot Weld (Top and Bottom Sheet), Seam Weld (Stiff and Flexible), 66, Stress-Life (SN) and Strain Life (eN), Spot Weld (Top and Bottom Sheet), Seam Weld (Stiff and Flexible), 92

MCOHE

Cohesive, 95

MPC

Explicit MPCs, 38

NLPARM

Nonlinear Static Subcase Parameters, 416

OUTPUT

Analysis Definition, 24, Advanced Output Requests, 481

PACINF

2D - 2D Solid - Acoustic Infinite, 209

PARAM,AUTOSPC

Solution Parameters, 312

PARAM,INREL

Solution Parameters, 312

PARAM,ALTRED

Solution Parameters, 312

PARAM,COUPMASS

Solution Parameters, 312

PARAM,K6ROT

Solution Parameters, 312

PARAM,WTMASS

Solution Parameters, 312

PARAM,GRDPNT

Solution Parameters, 312

PARAM,LGDISP

Nonlinear Static, 315, Nonlinear Transient, 344

PARAM,G

Complex Eigenvalue, 332, Frequency Response, 338, Transient Response, 341, Nonlinear Transient, 344

PARAM,W3

Transient Response, 341, Nonlinear Transient, 344

PARAM,W4

Transient Response, 341, Nonlinear Transient, 344

PARAM, POST PBAR PBCOMP

Main Index

Pages

Results Output Format, 405 1D - Beam - General Section (CBAR) - Standard Formulation, 114 1D - Beam - Lumped Section (CBEAM/PBCOMP), 128

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Patran Interface to MSC Nastran Preference Guide Currently Supported MSC Nastran Input Options

Table 2-4. Supported Bulk Data Entries Entry PBEAM

1D - Beam - Tapered Section (CBEAM) - Standard Formulation, 130

PBEAM71

Adaptive Mesh Post-Processing, 476

PBEAMD

Adaptive Mesh Post-Processing, 476

PBELTD

Adaptive Mesh Post-Processing, 476

PBEND

1D - Beam - Curved with General Section (CBEND), 124, 1D - Beam Curved with Pipe Section (CBEND), 126

PCOHE

2D - 2D Solid - Plane Strain - Interface, 195

PCOMP

2D - Shell - Thin - Laminate Plate- Standard Formulation, 165, 2D - Shell - Thin - Laminate - Revised Formulation, 167

PDAMP

0D - Grounded Scalar Damper (CDAMP1/CDAMP1D), 112

PELAS

0D - Grounded Scalar Spring (CELAS1/CELAS1D), 111

PELAS1

Adaptive Mesh Post-Processing, 476

PFTG

2D - Shell - Thin - Homogeneous - Standard Formulation, 156

PGAP

1D - Gap - Adaptive / Non Adaptive (CGAP), 144

PLOAD1

Distributed Load, 259

PLOAD2

Pressure, 252

PLOAD4

Pressure, 252

PLOADX1

Pressure, 252

PLOTEL

Main Index

Pages

1D - PLOTEL, 147

PLPLANE

2D - 2D Solid - Plane Strain - Standard Formulation, 186

PLSOLID

3D - Solid - Homogeneous - Hyperelastic, 222

PMASS

1D - Scalar Mass (CMASS1), 146

POINT

Element Creation, 21, 3D - Solid - Homogeneous - P-Formulation, 220

PROD

1D - Rod - General Section (CROD) - Standard Formulation, 138

PSHEAR

2D - Shear Panel, 215

PSHELL

2D - Shell - Thin - Homogeneous - Standard Formulation, 156, 2D - Shell - Homogeneous - Revised Formulation, 159, 2D - Shell - Thin Homogeneous - P-Formulation, 161, 2D - Shell - Thin - Homogeneous Linear Discrete Kirchhoff, 163, 2D - Shell - Thin - Laminate PlateStandard Formulation, 165, 2D - Shell - Thin - Laminate - Revised Formulation, 167, 2D - Shell - Thin - Equivalent Section - Standard Formulation, 169, 2D - Shell - Thin - Equivalent Section - Revised Formulation, 171, 2D - Shell - Thin - Equivalent Section - P-Formulation, 173

PSHELL1

Adaptive Mesh Post-Processing, 476

Chapter 2: Building A Model 13 Currently Supported MSC Nastran Input Options

Table 2-4. Supported Bulk Data Entries Entry PSHELLD

Adaptive Mesh Post-Processing, 476

PSOLID

3D - Solid - Homogeneous - Standard Formulation, 217

PSPRMA

Adaptive Mesh Post-Processing, 476

PTUBE

1D - Rod - Pipe Section (CTUBE), 140

PBEAM

1D - Beam - Tapered Section (CBEAM) - Standard Formulation, 130

PVAL

Element and p-Formulation Properties, 22, 3D - Solid - Homogeneous P-Formulation, 220

PVISC

1D - Damper - Viscous (CVISC), 143

RANDPS

Define Fatigue Load Sequences, 488

RBAR

RBAR MPCs, 40

RBE1

RBE1 MPCs, 42

RBE2

RBE2 MPCs, 43

RBE3

RBE3 MPCs, 44

RFORCE

Inertial Load, 257

RROD

RROD MPCs, 46

RSPLINE

RSPLINE MPCs, 47

RTRPLT

RTRPLT MPCs, 48

SESET

Select Superelements, 409, Translation Parameters, 298

SET1

Output Request Form Options, 484

SET4

Output Request Form Options, 484

SETREE

Select Superelements, 409

SPC1

Displacement / Velocty / Acceleration, 248

SPCD

Displacement / Velocty / Acceleration, 248

TABLFTG

Define Fatigue Load Sequences, 519

TABLEM1

Define Fatigue Load Sequences, 488 plus various material models

TABRND1

Define Fatigue Load Sequences, 488

TEMP

Temperature, 254

TEMPF

Temperature, 254

TEMPRB

Temperature, 254

TEMPP1

Temperature, 254

TIC TIM2PSD

Main Index

Pages

Initial Displacement, 257, Initial Velocity, 258 Define Fatigue Load Sequences, 488

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Patran Interface to MSC Nastran Preference Guide Currently Supported MSC Nastran Input Options

Table 2-4. Supported Bulk Data Entries Entry TSTEP

Transient Response, 341

TSTEPNL

Nonlinear Transient, 344, Nonlinear Transient Subcase Parameters, 419

UDNAME

Define Fatigue Load Sequences, 519

VCCT

Main Index

Pages

Crack (VCCT), 271

Chapter 2: Building A Model 15 Currently Supported MSC Nastran Input Options

MSC Nastran Implicit Nonlinear (SOL 400/600) The following Bulk Data entries are supported for SOL 400/600 analyses. 3D Contact Region BCBODY

Defines a flexible rigid contact body in 2D or 3D.

BCBOX*

Defines a 3D contact region.

BCHANGE

Changes definitions of contact bodies.

BCMATL*

Defines a 3D contact region by element material.

BCMOVE

Defines movement of bodies in contact.

BCPARA

Defines contact parameters.

BCPROP*

Defines a 3d contact region by element properties.

BCTABLE

Defines a contact table.

BSURF

Defines a contact body or surface by element IDs.

GMNURB

3D contact region made up of NURBS.

BCTABL1

Defines a Contact Table (New Form).

BCONECT

Defines the Touching and Touched Contact Bodies.

BCONPRG

Geometric Contact Parameters of Touching Bodies.

BCONPRP

Physical Contact Parameters of Touching Bodies.

BCBODY1

Flexible or Rigid Contact Body in 2D and 3D (New Form).

BCBDPRP

Contact Body Parameters.

BCRIGID

Defines a Rigid Contact Body.

BCRGSRF

Rigid Contact Body Surface List.

BCPATCH

Defines a Rigid Contact Body Made up of Quadrilateral Patches.

BCNURB2

Defines a 2D Rigid Contact Body Made up of NURBS.

BCNURBS

Defines a Rigid Contact Body Made up of NURBS.

BCTRIM

Defines the Geometry of Trimming Curves.

BCONTACT

Initiates and controls 3D contact in SOLs 101, 400, and 700. It can refer to BCTABL1, BCONECT or BCTABLE Bulk Data entry.

Initial Conditions

Main Index

IPSTRAIN*

Defines initial plastic strain values.

ISTRESS*

Defines initial stress values.

MARCIN

Insert a text string in MSC.Marc.

MARCOUT

Selects data recovery output.

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Patran Interface to MSC Nastran Preference Guide Currently Supported MSC Nastran Input Options

Materials MATEP

Elasto-plastic material properties.

MATF

Specifies material failure model.

MATG*

Gasket material properties.

MATHE

Hyperelastic material properties.

MATHP

Hyperelastic material properties.

MATHED

Damage model properties for hyperelastic materials.

MATORT

Elastic 3D orthotropic material properties.

MATTEP

Thermoelastic-Plastic material properties.

MATTG*

Temperature variation of interlaminar materials.

MATTHE

Thermo hyperelastic material.

MATTORT*

Thermoelastic orthotropic material

MATTVE*

Thermo-visco-elastic material properties

MATVE*

Viscoelastic material properties

MATVP

Viscoplastic or creep material properties

Note:

* Not supported in initial release of Patran (2004).

Solution Control NLAUTO

Parameters for automatic load/time stepping.

NLDAMP

Defines damping constants.

NLSTRAT

Strategy Parameters for nonlinear structural analysis.

PARAMARC

Parallel domain decomposition.

RESTART

Restart data.

Element Properties NTHICK

Main Index

Defines nodal thickness values for beams, plates, and/or shells.

Chapter 2: Building A Model 17 Currently Supported MSC Nastran Input Options

MSC Nastran Explicit Nonlinear (SOL 700) The following Bulk Data entries are supported for SOL 700 analyses. Materials

Main Index

MATD001

Isotropic Elastic material for beam, shell and solid.

MATD003

Isotropic and kinematic hardening plasticity.

MATD005

Isotropic materials to model soil and foam.

MATD006

Isotropic viscoelastic material.

MATD007

Isotropic material to model nearly incompressible continuum rubber.

MATD012

Isotropic plasticity for 3D solids.

MATD014

Isotropic materials to model soil and foam with failure.

MATD015

Isotropic Johnson/Cook strain and temperature sensitive plasticity.

MATD019

Isotropic strain rate dependent material.

MATD020

Isotropic rigid material.

MATD022

Orthotropic material with optional brittle failure for composites.

MATD024

Isotropic elasto-plastic material with stress x strain curve and strain rate dependency.

MATD026

Anisotropic honeycomb and foam material.

MATD027

Isotropic material to model rubber using two variables.

MATD028

Isotropic elasto-plastic material for beam and shell.

MATD030

Isotropic superelastic material.

MATD031

Isotropic material to model rubber using the Frazer-Nash formulation.

MATD032

Orthotropic laminated glass material.

MATD057

Isotropic material to model highly compressible low density foams.

MATD058

*MAT_LAMINATED_COMPOSITE_FABRIC

MATD062

Isotropic material to model viscous foams.

MATD063

Isotropic material to model crushable foams.

MATD064

Isotropic elasto-plastic material with a power law hardening.

MATD067

*MAT_NONLINEAR_ELASTIC_DISCRETE_BEAM

MATD068

*MAT_NONLINEAR_PLASTIC_DISCRETE_BEAM

MATD069

*MAT_SID_DAMPER_DISCRETE_BEAM

MATD070

*MAT_HYDRAULIC_GAS_DAMPER_DISCRETE_BEAM

MATD071

*MAT_CABLE_DISCRETE_BEAM

MATD073

*MAT_LOW_DENSITY_VISCOUS_FOAM

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Patran Interface to MSC Nastran Preference Guide Currently Supported MSC Nastran Input Options

MATD074

*MAT_ELASTIC_SPRING_DISCRETE_BEAM

MATD076

*MAT_GENERAL_VISCOELASTIC

MATD083

*MAT_FU_CHANG_FOAM

MATD087

*MAT_CELLULAR_RUBBER

MATD093

*MAT_ELASTIC_6DOF_SPRING_DISCRETE_BEAM

MATD094

*MAT_INELASTIC_SPRING_DISCRETE_BEAM

MATD095

*MAT_INELASTIC_6DOF_SPRING_DISCRETE_BEAM

MATD097

*MAT_GENERAL_JOINT_DISCRETE_BEAM

MATD100

Isotropic spotweld material.

MATD103

Anisotropic viscoplastic material.

MATD119

*MAT_GENERAL_NONLINEAR_6DOF_DISCRETE_BEAM

MATD121

*MAT_GURSON_RCDC

MATD126

*MAT_MODIFIED_HONEYCOMB

MATD20M

*MAT_RIGID

MATDB01

*MAT_SEATBELT

MATDS01

*MAT_SPRING_ELASTIC

MATDS02

*MAT_DAMPER_VISCOUS

MATDS03

*MAT_SPRING_ELASTOPLASTIC

MATDS04

*MAT_SPRING_NONLINEAR_ELASTIC

MATDS05

*MAT_DAMPER_NONLINEAR_VISCOUS

MATDS06

*MAT_SPRING_GENERAL_NONLINEAR

MATDS07

*MAT_SPRING_MAXWELL

MATDS08

*MAT_SPRING_INELASTIC

MATDS13

*MAT_SPRING_TRILINEAR_DEGRADING

MATDS14

*MAT_SPRING_SQUAT_SHEARWALL

MATDS15

*MAT_SPRING_MUSCLE

Loads and Boundary Conditions TIC3

Defines initial rotational field.

WALL

Defines planar rigid wall.

Elements and Properties

Main Index

CDAMP1D

Scalar damper connection for SOL 700

CELAS1D

Scalar spring connection for SOL 700.

Chapter 2: Building A Model 19 Currently Supported MSC Nastran Input Options

Solution Controls Form

Main Index

Parameters

Execution Control Parameters

DYSTATIC, DYBLDTIM, DYINISTEP, DYTSTEPERODE, DYMINSTEP, DYMAXSTEP, DYSTEPFCTL, DYTERMNENDMAS, DYTSTEPDT2MS

General Parameters

DYLDKND, DYCOWPRD, DYCOWPRP, DYBULKL, DYHRGIHQ, DYRGQH, DYENERGYHGEN, DYSHELLFORM, DYSHTHICK, DYSHNIP

Contact Parameters

DYCONSLSFAC, DYCONRWPNAL, DYCONPENOPT, DYCONTHKCHG, DYCONENMASS, DYCONECDT, DYCONIGNORE, DYCONSKIPTWG

Binary Output Database File Parameters

DYBEAMIP, DYMAXINT, DYNEIPS, DYNINTSL, DYNEIPH, DYSTRFLG, DYSIGFLG, DYEPSFLG, DYRLTFLG, DYENGFLG, DYCMPFLG, DYIEVERP, DYDCOMP, DYSHGE, DYSTSSZ, DYN3THDT

DAMPGBL

Dynamic relaxation control.

20

Patran Interface to MSC Nastran Preference Guide Adaptive (p-Element) Analysis with the MSC Nastran Preference

2.3

Adaptive (p-Element) Analysis with the MSC Nastran Preference In Version 68 of MSC. Nastran, MSC introduced p-adaptive analysis using solid elements. The Patran MSC Nastran Preference provides support for this new capability. There are some fundamental differences in approach to model building and results import for p-element analyses; this section will serve as a guide to these. MSC .Nastran Version 69 extends the Version 68 capabilities for p-adaptive analysis in two areas. Shell and beam elements have been added and p-shells and p-beams can be used for linear dynamic solution sequences. Patran Version 6.0 supports both of these capabilities.

Main Index

Chapter 2: Building A Model 21 Adaptive (p-Element) Analysis with the MSC Nastran Preference

Element Creation MSC Nastran supports adaptive, p-element analyses with the 3D-solid CTETRA, CPENTA, and CHEXA elements; 2D-solid TRIA, and QUAD elements; shells TRIA, and QUAD elements; beams BAR elements. Patran and MSC Nastran allow TET4, TET10, TET16, TET40, WEDGE6, WEDGE15, WEDGE52, HEX8, HEX20, and HEX64 for p-adaptive analysis for 3D-solids; TRIA3, TRIA6, TRIA7, TRIA9, TRIA13, QUAD4, QUAD8, QUAD9, QUAD12, and QUAD16 for p-adaptive analysis for 2Dsolids and membranes; TRIA3, TRIA6, TRIA7, TRIA9, TRIA13, QUAD4, QUAD8, QUAD9, QUAD12, and QUAD16 for p-adaptive analysis for shells; BAR2, BAR3, and BAR4 for p-adaptive analysis for beams. The preferred approach, when beginning a new model, is to use the higher-order elements--HEX64, WEDGE52, TET40, and TET16, or TRIA13 and QUAD16, or BAR4. The support for lower-order elements is provided primarily to support existing models. The higher-order cubic elements allow more accurate definition of the geometry and more accurate postprocessing of results from the MSC Nastran analysis.The translator generates the appropriate MSC Nastran FEEDGE and POINT entities for all curved edges on the p-elements. Models with HEX64 and WEDGE52 elements are easily created with the Patran Iso Mesher; models with TET16 elements can be created with the Tet Mesher. Models with QUAD16 and TRIA13 elements can be created using the Iso Mesher or the Paver. For p-elements, Patran generates cubic edges to fit the underlying geometry. The cubic edge consists of two vertex grid points and two points in between. Adjacent cubic edges are not necessarily C1 continuous. If the original geometry is smooth, the cubic edges may introduce kinks which cause false stress concentrations. Then, the p-element produces unrealistic results especially for thin curved shells. In Version 7 of Patran, for cubic elements, the two midside nodes on each edge are adjusted so that the edges of adjacent elements are C1 continuous. The adjustment is done in the Pat3Nas translator. After the Pat3Nas translator is executed, the location of the two midside nodes in the Patran database has changed. The user is informed with a warning message. The user can turn the adjustment of midside nodes ON and OFF with the environment variable PEDGE_MOVE. By default, the midside nodes are adjusted to make the adjacent elements C1 continuous. For PEDGE_MOVE set to OFF, the points on a cubic edge are not adjusted. Patran generates the input for MSC Nastran. For cubic edges, FEEDGE Bulk Data entries with POINTs are written. By default, the location of the two POINTs is moved to 1/3 and 2/3 of the edge in MSC Nastran. The points generated by Patran must not be moved. Therefore, a parameter entry PARAM, PEDGEP, 1 is written by Patran. PEDGEP=1 indicates that incoming POINTs are not moved in MSC Nastran. The default is PEDGEP= 0, MSC Nastran will move the two POINTs to 1/3 and 2/3 of the edge. The C1 continuous cubic edges improve the accuracy of p-element results. In the Version 69 Release Guide, a cylinder under internal pressure was tested to determine the quality of shell p-elements for curved geometry. The accuracy of the results was very good when exact geometry was used. With C1 continuous edges we recover the same quality of results within single precision accuracy.

Main Index

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Patran Interface to MSC Nastran Preference Guide Adaptive (p-Element) Analysis with the MSC Nastran Preference

Element and p-Formulation Properties Both element and p-formulation properties are defined using the Element Properties application by choosing Action: Create, Dimension: 1D/2D/ or 3D, Type: Beam/Shell/Bending Panel/2D Solid/Membrane/ or Solid, and p-Formulation on the main form. Most of the properties are optional and have defaults; the material property name is required. Two properties that may need to be defined are Starting P-orders and Maximum P-orders. These properties specify the polynomial orders for the element interpolation functions in the three spatial directions. Although these are integer values, in Patran, each property is defined using the Patran vector definition. At first, this may seem peculiar, but it gives the user access to many useful tools in the Patran system for defining and manipulating these properties. Typically, a user would define these properties with a syntax like to prescribe polynomial orders of 3, 4, and 2 in the X, Y, and Z directions. Patran will convert these values to floating point , but the Patran MSC Nastran Preference will interpret them. This vector syntax is convenient primarily because it allows these properties to be defined using the Fields application. In a case where the material properties are constant over the model, but it is desirable to prescribe a distribution of p-orders, vector fields can be defined and specified in a single property definition. The Patran MSC Nastran Preference will provide additional help for this modeling function. At the end of an adaptive analysis, when results are imported, vector, spatial fields will optionally be created containing the p-orders used for each element for each adaptive cycle. To repeat a single adaptive cycle, it is necessary only to modify the element properties by selecting the appropriate field. A common use of the Maximum P-orders property is in dealing with elements in the vicinity of stress singularities. These singularities may be caused by the modeling of the geometry (e.g., sharp corners), boundary conditions (e.g., point constraints), or applied forces (e.g., point forces). Sometimes it is easier to tell the adaptive analysis to “ignore” these singular regions than it is to change the model. This can be done by setting the Maximum P-orders property for elements in this region to low values (e.g., or . These elements are sometimes called “sacrificial” elements.

Main Index

Chapter 2: Building A Model 23 Adaptive (p-Element) Analysis with the MSC Nastran Preference

Loads and Boundary Conditions It is well known in solid mechanics that point forces and constraints cause the stress field in the body to become infinite. In p-adaptive analyses, care must be taken in finite element creation and loads application to ensure that these artificial high-stress regions don’t dominate the analysis. Generally, the best results are obtained with distributed loads (pressures) or distributed displacements. There are two options under Loads/BCs for applying distributed displacements. The Element Uniform and Element Variable types under Displacements allow displacement constraints to be applied to the faces of solid elements. If the elements are p-elements, the appropriate FEFACE and GMBC entries are produced. If applied to non-p-elements, the appropriate SPC1 or SPCD entries are produced. Several new loads and boundary conditions support the p-shell and p-beam elements. Distributed loads can be applied to beam elements or to the edge of shell elements. Pressure loads can be applied to the faces of p-shell elements. Temperature loads can be applied to either the nodes or the elements.

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Patran Interface to MSC Nastran Preference Guide Adaptive (p-Element) Analysis with the MSC Nastran Preference

Analysis Definition Adaptive linear static and normal modes analyses are supported in Version 68 of MSC .Nastran; both solution types are supported by the Patran MSC Nastran Preference. Only a few parameters on the Analysis forms may need to be changed for p-element analyses. If running a version of MSC . Nastran prior to Version 68.2 (i.e., Version 68, or 68.1), the OUTPUT2 Request option on the Translation Parameters form must be set to Alter File in order to process the results in Patran. The Solution Parameters forms for the linear static and normal modes analyses contain a Max p-Adaptive Cycles option, which is defaulted to 3. The Subcase Parameters form under Subcase Create has options to limit the participation of this subcase in the adaptive error analysis. Finally, the Advanced Output Requests form under Subcase Create has an option to define whether results are to be produced for all adaptive cycles or only every nth adaptive cycle.

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Chapter 2: Building A Model 25 Adaptive (p-Element) Analysis with the MSC Nastran Preference

Results Import and Postprocessing Two different approaches are provided for postprocessing results from MSC Nastran p-element analyses. Both approaches rely on MSC Nastran creating results for a “VU mesh” where each p-element is automatically subdivided into a number of smaller elements. In the standard approach with the default MSC Nastran VU mesh (3 x 3 x 3 elements) for solids, (3 x 3 elements) for shells and (3 elements) for beams, the results will automatically be mapped onto the Patran nodes and elements during import. This mapping will occur for all 10, Patran solid element topologies mentioned above. The most accurate mapping and postprocessing takes place when results are mapped to the higher-order Patran elements. When the adaptive analysis process increases the p-orders in one or more elements beyond 3, the 3 x 3 x 3 VU mesh, mapping, and postprocessing may not be sufficiently accurate. The Patran MSC Nastran Preference provides a second approach to handle this situation. In this case, a user can specify a higherorder VU mesh (e.g. 5 x 5 x 5) on the MSC Nastran OUTRCV entry and then import both model data and results entities into a new, empty Patran database. In this case, the VU mesh and results are imported directly, rather than mapped and can be post-processed with greater accuracy. The OUTRCV entry is currently supported only with the Bulk Data Include File option on the Translation Parameters form. It should be noted that, with this import mode, displays of element results (e.g., fringe plots) may be discontinuous across parent, p-element boundaries. This occurs because the VU grids generated by MSC Nastran are different in each p-element. Along element boundaries there are coincident nodes and a result associated with each one. The user should not try to perform an Equivalence operation to remove these coincident nodes. If this is done, subsequent postprocessing operations will likely be incorrect. For both postprocessing options, a result case is created for each adaptive cycle in the analysis. The result types in this result case will depend on specific options selected on the Output Request form. By default, the Adaptive Cycle Output Interval option is equal to zero. This means that output quantities specific to p-elements will be written only for the last cycle. If postprocessing of results from intermediate cycles is desired, the Adaptive Cycle Output Interval option should be set equal to one. One of the key uses of output from intermediate adaptive cycles is in examining the convergence of selected quantities (e.g., stresses). This can be done using the X-Y plotting capability under the Results application.

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Patran Interface to MSC Nastran Preference Guide Adaptive (p-Element) Analysis with the MSC Nastran Preference

Potential Pitfalls There are several areas where a user can encounter problems producing correct p-element models for MSC Nastran. One is the incorrect usage of the midside nodes in the Patran higher order-elements. These nodes are used in p-element analysis only for defining the element geometry; analysis degrees of freedom are not associated with these nodes. Therefore it is illegal, for example, to attach non p-elements to assign loads or boundary conditions to these nodes. One way this can occur inadvertently is if a nodal force is applied to the face of a Patran solid. This force is interpreted as a point force at every node (including the midside nodes) on the face of the solid. For the p-elements, this is not valid. This type of load should instead be applied as an element uniform or element variable pressure.

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Chapter 2: Building A Model 27 Adaptive (p-Element) Analysis with the MSC Nastran Preference

Adaptive Analysis of Existing Models Modifying an existing solid model for adaptive, p-element analysis is relatively straightforward. The first step is to read the NASTRAN input file into Patran using the Analysis/Read Input File option. The model may contain any combination of linear or quadratic tetra, penta, or hexa elements. The second step is to use the Element Props/Modify function to change the Option for all solid properties from Standard Formulation to P-Formulation. The element properties form for p-formulation solids has many options specific to p-element analysis; but they all have appropriate defaults. This property modification step is the only change that must be made before submitting the model for analysis. Often, however, as discussed in Potential Pitfalls, 26, it is appropriate to modify the types of loads and boundary conditions applied to the model. For example, in non p-element models, displacement constraints are applied using MSC Nastran SPC entries at grid points. In p-element analyses, elementoriented displacement constraints are more appropriate. Existing displacement LBCs can be modified using the Loads/BCs/Modify/Displacement option. For an SPC type of displacement constraint, the LBC type is nodal. For a p-element analysis, Element Uniform or Element Variable displacement constraints are more appropriate. The application region must be changed from a selection of nodes to a selection of element faces. As described above, nodal forces can be troublesome in p-element analyses. If possible, it is beneficial to redefine point forces as pressures acting on an element face. If this is not possible, an alternative is to limit the p-orders in the elements connected to the node with the point force; this can be done by defining a new element property for these elements and defining the Maximum P-orders vector appropriately. Element pressures, inertial loads, and nodal temperatures defined in the original model need not be changed for the p-element analysis.

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Patran Interface to MSC Nastran Preference Guide Coordinate Frames

2.4

Coordinate Frames Coordinate frames will generate a unique CORD2R, CORD2C, or CORD2S Bulk Data entry, depending on the specified coordinate frame type. The CID field is defined by the Coord ID assigned in Patran. The RID field may or may not be defined, depending on the coordinate frame construction method used in Patran. The A1, A2, A3, B1, B2, B3, C1, C2, and C3 fields are derived from the coordinate frame definition in Patran.

Only Coordinate Frames that are referenced by nodes, element properties, or loads and boundary conditions can be translated. For more information on creating coordinate frames see Creating Coordinate Frames (p. 469) in the Geometry Modeling - Reference Manual Part 2. To output all the coordinate frames defined in the model whether referenced or not, set the environment variable “WRITE_ALL_COORDS” to ON.

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Chapter 2: Building A Model 29 Finite Elements

2.5

Finite Elements The Finite Elements Application in Patran allows the definition of basic finite element construction. Created under Finite Elements are the nodes, element topology, multi-point constraints, and Superelement.

For more information on how to create finite element meshes, see Mesh Seed and Mesh Forms (p. 25) in the Reference Manual - Part III.

Nodes Nodes in Patran will generate unique GRID Bulk Data entries in MSC Nastran. Nodes can be created either directly using the Node object, or indirectly using the Mesh object. Each node has associated Reference (CP) and Analysis (CD) coordinate global frames. The ID is taken directly from the assigned node ID. The X1, X2, and X3 fields are defined in the specified CP coordinate frame. If no reference frame is assigned, the system is used. The PS and SEID fields on the GRID entry are left blank.

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Patran Interface to MSC Nastran Preference Guide Finite Elements

Entry Coordinate Frame

Description The analysis frame (CD of the GRID) is the coordinate system in which the displacements, degrees of freedom, constraints, and solution vector are defined. The coordinate system in which the node location is defined (CP of the GRID) can be either the reference coordinate frame, the analysis coordinate frame, or a global reference (blank), depending on the value of the forward translation parameter “Node Coordinates.”

Elements The Finite Elements Application in Patran assigns element connectivity, such as Quad4, for standard finite elements. The type of MSC Nastran element to be created is not determined until the element properties are assigned (for example, shell or 2D solid). See the Element Properties Form, 101 for details

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Chapter 2: Building A Model 31 Finite Elements

concerning the MSC Nastran element types. Elements can be created either directly using the Element object, or indirectly using the Mesh object

Entry

Main Index

Description

Finite Elements Form

This type of form is used to create a 1D, 2D, or 3D element mesh.

Node

Beginning IDs for nodes to be created.

Element

Beginning IDs for elements to be created.

Elem Shape

Elem Shape is used to specify the shape of the elements created by meshing. For example, the shape for a 2D element can be either triangular or quadralateral.

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Patran Interface to MSC Nastran Preference Guide Finite Elements

Entry

Description

Mesher

Mesher is used to specify how the element mesh is to be created; for example, IsoMesh, Paver. The type of geometry (for example, simple (green) or complex (magenta) surface) may determine the choice of the mesher.

Surface List

List of surface IDs of surfaces to be meshed. For example Surface 1, 2, 3, or Surface 1:3.

Value

The value of Global Edge Length specifies the approximate size of the elements created when meshing.

Select Existing Prop...

The button Select Existing Prop... is used to select an existing element property (for example, 2D Shell) that will be assigned to the elements created by meshing.

Create New Property

The button Create New Property is used to create an element property that will be assigned to the elements that will be created by meshing. During creating the element property no application region can be specified; it is specified automatically using all the elements created by meshing.

Prop Name & Prop Type

This “ghosted” area will become dark when an element property is selected.

Multi-point Constraints Multi-point constraints (MPCs) can also be created from the Finite Elements Application. These are special element types that define a rigorous behavior between several specified nodes. The forms for

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Chapter 2: Building A Model 33 Finite Elements

creating MPCs are found by selecting MPC as the Object on the Finite Elements form. The full functionality of the MPC forms are defined in Create Action (FEM Entities).

Entry MPC ID

Main Index

Description Used to specify the ID to associate to the MPC when it is created.

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Patran Interface to MSC Nastran Preference Guide Finite Elements

MPC Types To create an MPC, first select the type of MPC to be created from the option menu. The MPC types that appear in the option menu are dependent on the current settings of the Analysis Code and Analysis Type preferences. The following table describes the MPC types which are supported for MSC Nastran.

Main Index

MPC Type

Analysis Type

Description

Explicit

Structural

Creates an explicit MPC between a dependent degree of freedom and one or more independent degrees of freedom. The dependent term consists of a node ID and a degree of freedom, while an independent term consists of a coefficient, a node ID, and a degree of freedom. An unlimited number of independent terms can be specified, while only one dependent term can be specified. The constant term is not allowed in MSC Nastran.

RSSCON Surf-Vol

Structural

Creates an RSSCON type MPC between a dependent node on a linear 2D plate element and two independent nodes on a linear 3D solid element to connect the plate element to the solid element. One dependent and two independent terms can be specified. Each term consists of a single node.

Rigid (Fixed)

Structural and Explicit Nonlinear

Creates a rigid MPC between one independent node and one or more dependent nodes in which all six structural degrees of freedom are rigidly attached to each other. An unlimited number of dependent terms can be specified, while only one independent term can be specified. Each term consists of a single node. There is no constant term for this MPC type.

RBAR

Structural and Explicit Nonlinear

Creates an RBAR element, which defines a rigid bar between two nodes. Up to two dependent and two independent terms can be specified. Each term consists of a node and a list of degrees of freedom. The nodes specified in the two dependent terms must be the same as the nodes specified in the two independent terms. Any combination of the degrees of freedom of the two nodes can be specified as independent as long as the total number of independent degrees of freedom adds up to six. There is no constant term for this MPC type.

RBE1

Structural

Creates an RBE1 element, which defines a rigid body connected to an arbitrary number of nodes. An arbitrary number of dependent terms can be specified. Each term consists of a node and a list of degrees of freedom. Any number of independent terms can be specified as long as the total number of degrees of freedom specified in all of the independent terms adds up to six. Since at least one degree of freedom must be specified for each term there is no way the user can create more that six independent terms. There is no constant term for this MPC type.

Chapter 2: Building A Model 35 Finite Elements

Main Index

MPC Type

Analysis Type

Description

RBE2

Structuraland Explicit Nonlinear

Creates an RBE2 element, which defines a rigid body between an arbitrary number of nodes. Although the user can only specify one dependent term, an arbitrary number of nodes can be associated to this term. The user is also prompted to associate a list of degrees of freedom to this term. A single independent term can be specified, which consists of a single node. There is no constant term for this MPC type.

RBE3

Structuraland Explicit Nonlinear

Creates an RBE3 element, which defines the motion of a reference node as the weighted average of the motions of a set of nodes. An arbitrary number of dependent terms can be specified, each term consisting of a node and a list of degrees of freedom. The first dependent term is used to define the reference node. The other dependent terms define additional node/degrees of freedom, which are added to the m-set. An arbitrary number of independent terms can also be specified. Each independent term consists of a constant coefficient (weighting factor), a node, and a list of degrees of freedom. There is no constant term for this MPC type.

RROD

Structural

Creates an RROD element, which defines a pinned rod between two nodes that is rigid in extension. One dependent term is specified, which consists of a node and a single translational degree of freedom. One independent term is specified, which consists of a single node. There is no constant term for this MPC type.

RSPLINE

Structural

Creates an RSPLINE element, which interpolates the displacements of a set of independent nodes to define the displacements at a set of dependent nodes using elastic beam equations. An arbitrary number of dependent terms can be specified. Each dependent term consists of a node, a list of degrees of freedom, and a sequence number. An arbitrary number of independent nodes (minimum of two) can be specified. Each independent term consists of a node and a sequence number. The sequence number is used to order the dependent and independent terms with respect to each other. The only restriction is that the first and the last terms in the sequence must be independent terms. A constant term, called D/L Ratio, must also be specified.

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Patran Interface to MSC Nastran Preference Guide Finite Elements

Main Index

MPC Type

Analysis Type

Description

RTRPLT

Structural

Creates an RTRPLT element, which defines a rigid triangular plate between three nodes. Up to three dependent and three independent terms can be specified. Each term consists of a node and a list of degrees of freedom. The nodes specified in the three dependent terms must be the same as the nodes specified in the three independent terms. Any combination of the degrees of freedom of the three nodes can be specified as independent as long as the total number of independent degrees of freedom adds up to six. There is no constant term for this MPC type.

Cyclic Symmetry

Structural

Describes cyclic symmetry boundary conditions for a segment of the model. If a cyclic symmetry solution sequence is chosen, such as “SOL 114,” then CYJOIN, CYAX and CYSYM entries are created. If a solution sequence that is not explicitly cyclic symmetric is chosen, such as “SOL 101,” MPC and SPC entries are created. Be careful, for this option automatically alters the analysis coordinate references of the nodes involved. This could erroneously change the meaning of previously applied load and boundary conditions, as well as element properties.

Sliding Surface

Structural

Describes the boundary conditions of sliding surfaces, such as pipe sleeves. These boundary conditions are written to the NASTRAN input file as explicit MPCs. Be careful, for this option automatically redefines the analysis coordinate references of all affected nodes. This could erroneously alter the meaning of previously applied load and boundary conditions, as well as element properties.

RBAR1

Structural

This is an alternate (simplified) form for RBAR. Creates an RBAR1 element, which defines a rigid bar between two nodes, with six degrees of freedom at each end. Each dependent term consists of a node and a list of degrees of freedom, while the independent term consists only of a node (with all six degrees of freedom implied). The constant term is the thermal expansion coefficient, ALPHA.

Chapter 2: Building A Model 37 Finite Elements

Main Index

MPC Type

Analysis Type

Description

RTRPLT1

Structural

Alternative format to define a rigid triangular plate element connecting three grid points. Creates an RTRPLT1 element, which defines a rigid triangular plate between three nodes. Each dependent term consists of a node and a list of degrees of freedom, while the independent term consists only of the node (with all six degrees of freedom implied). The constant term is the thermal expansion coefficient, ALPHA.

RJOINT

Structural

Creates an RJOINT element, which defines a rigid joint element connecting two coinciding grid points. Each dependent term consists of a node and a list of degrees of freedom, while the independent term consists only of a node (with all six degrees of freedom implied). There is no constant term for this MPC type.

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Patran Interface to MSC Nastran Preference Guide Finite Elements

Degrees of Freedom Whenever a list of degrees of freedom is expected for an MPC term, a listbox containing the valid degrees of freedom is displayed on the form. The following degrees of freedom are supported by the Patran MSC Nastran MPCs for the various analysis types: Degree of freedom

Analysis Type

UX

Structural

UY

Structural

UZ

Structural

RX

Structural

RY

Structural

RZ

Structural

Note:

Care must be taken to make sure that a degree of freedom that is selected for an MPC actually exists at the nodes. For example, a node that is attached only to solid structural elements will not have any rotational degrees of freedom. However, Patran will allow you to select rotational degrees of freedom at this node when defining an MPC.

Explicit MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and Explicit is the selected type. This form is used to create an MSC Nastran MPC Bulk Data entry. The difference in explicit MPC equations between Patran and MSC Nastran will result in the A1 field of the MSC Nastran entry being set to -1.0.

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Chapter 2: Building A Model 39 Finite Elements

Entry

Main Index

Description

Dependent Terms (1)

Holds the dependent term information. This term will define the fields for G1 and C1 on the MPC entry. Only one node and DOF combination may be defined for any given explicit MPC. The A1 field on the MPC entry is automatically set to -1.0.

Independent Terms (No Max)

Holds the independent term information. These terms define the Gi, Ci, and Ai fields on the MPC entry, where i is greater than one. As many coefficient, node, and DOF combinations as desired may be defined.

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Patran Interface to MSC Nastran Preference Guide Finite Elements

Rigid (Fixed)

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and Rigid (Fixed) is the selected type. This form is used to create an MSC Nastran RBE2 Bulk Data entry. The CM field on the RBE2 entry will always be 123456.

Entry

Description

Dependent Nodes (No Max) Holds the dependent term information. This term defines the GMi fields on the RBE2 entry. As many nodes as desired may be selected as dependent terms. Independent Nodes (1)

Holds the independent term information. This term defines the GN field on the RBE2 entry. Only one node may be selected.

RBAR MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and RBAR is the selected type. This form is used to create an MSC Nastran RBAR Bulk Data entry and defines a rigid bar with six degrees of freedom at each end. Both the Dependent Terms and the Independent Terms lists can have either 1 or 2 node references. The total number of referenced nodes,

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Chapter 2: Building A Model 41 Finite Elements

however, must be 2. If either or both of these lists references 2 nodes, then there must be an overlap in the list of referenced nodes.

Entry

Main Index

Description

Dependent Terms (Min=1,Max=2)

Holds the dependent term information. Either one or two nodes may be defined as having dependent terms. The Nodes define the GA and GB fields on the RBAR entry. The DOFs define the CMA and CMB fields.

Independent Terms (Min=1,Max=2)

Holds the independent term information. Either one or two nodes may be defined as having independent terms.The Nodes define the GA and GB fields on the RBAR entry.The DOFs define the CNA and CNB fields.

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Patran Interface to MSC Nastran Preference Guide Finite Elements

RBE1 MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and RBE1 is the selected type. This form is used to create an MSC Nastran RBE1 Bulk Data entry.

Entry

Description

Dependent Terms (No Max) Holds the dependent term information. Defines the GMi and CMi fields on the RBE1 entry. An unlimited number of nodes and DOFs may be defined here. Independent Terms (Min=1,Max=6)

Main Index

Holds the independent term information. Defines the GNi and CNi fields on the RBE1 entry. The total number of Node/DOF pairs defined must equal 6, and be capable of representing any general rigid body motion.

Chapter 2: Building A Model 43 Finite Elements

RBE2 MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and RBE2 is the selected type. This form is used to create an MSC Nastran RBE2 Bulk Data entry.

Entry

Main Index

Description

Dependent Terms (1)

Holds the dependent term information. This term defines the GMi and CM fields on the RBE2 entry. As many nodes as desired may be selected as dependent terms.

Independent Terms (1)

Holds the independent term information. This term defines the GN field on the RBE2 entry. Only one node may be selected.

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Patran Interface to MSC Nastran Preference Guide Finite Elements

RBE3 MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and RBE3 is the selected type. This form is used to create a MSC Nastran RBE3 Bulk Data entry

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Chapter 2: Building A Model 45 Finite Elements

.

Entry

Description

Dependent Terms (No Max) Holds the dependent term information. Defines the GMi and CMi fields on the RBE3 entry. The first dependent term will be treated as the reference node, REFGRID and REFC. The rest of the dependent terms become the GMi and CMi components. Independent Terms (No Max)

Main Index

Holds the independent term information. Defines the Gi, j, Ci, and WTi fields on the RBE3 entry.

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RROD MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and RROD is the selected type. This form is used to create an MSC Nastran RROD Bulk Data entry.

Entry

Main Index

Description

Dependent Terms (1)

Holds the dependent term information. Defines the GB and CMB on the RROD entry. Only one translational DOF may be referenced for this entry.

Independent Terms (1)

Holds the independent term information. Defines the GA field on the RROD entry. The CMA field is left blank.

Chapter 2: Building A Model 47 Finite Elements

RSPLINE MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and RSPLINE is the selected type. This form is used to create an MSC Nastran RSPLINE Bulk Data entry. The D/L field for this entry is defined on the main MPC form. This MPC type is typically used to tie together two dissimilar meshes.

Entry

Main Index

Description

Dependent Terms (Min=1,Max=97)

Holds the dependent term information.

Independent Terms (Min=2,Max=98)

Holds the independent term information. Terms with the highest and lowest sequence numbers must be independent.

Sequence

Determines what sequence the independent and dependent terms will be written to the RSPLINE entry.

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Patran Interface to MSC Nastran Preference Guide Finite Elements

RTRPLT MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and RTRPLT is the selected type. This form is used to create an MSC Nastran RTRPLT Bulk Data

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Chapter 2: Building A Model 49 Finite Elements

entry.

Entry

Main Index

Description

Dependent Terms (Min=1,Max=3)

Holds the dependent term information. Defines the GA, GB, GC, CMA, CMB, and CMC fields of the RTRPLT entry.

Independent Terms (Min=2,Max=3)

Holds the independent term information. The total number of nodes referenced in both the dependent terms and the independent terms must equal three. There must be exactly six independent degrees of freedom, and they must be capable of describing rigid body motion. Defines the GA, GB, GC, CNA, CNB, and CNC fields of the RTRPLT entry.

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Cyclic Symmetry MPCs

The Cyclic Symmetry MPC created by this form will be translated into CYJOIN, CYAX, and CYSYM entries if cyclic symmetric is the selected type, see Solution Parameters, 312, or into SPC and MPC entries if the requested type is not explicitly cyclic symmetric.

Entry Cyclic Symmetry

Description If the type selected is Cyclic Symmetry, the type of symmetry will always be rotational. NOTE: MPC option will automatically overwrite the analysis coordinate references on all the nodes belonging to the Dependent and Independent Regions. Be careful that this does not erroneously change the meaning of previously applied loads and boundary conditions, or element properties.

Main Index

Cylindrical Coord. Frame

Any node lying on the Z axis will be automatically written to the CYAX entry.

Dependent Region

Side 2 of the CYJOIN entries.

Independent Region

Side 1 of the CYJOIN entries.

Chapter 2: Building A Model 51 Finite Elements

Sliding Surface MPCs

The Sliding Surface MPC created by this form will be translated into explicit MPCs in the NASTRAN input file.

Entry Sliding Surface

Main Index

Description If a Sliding Surface type is used, note that this MPC option will automatically overwrite the analysis coordinate references on all the nodes belonging to the Dependent and Independent Regions. Be careful that this does not erroneously change the meaning of previously applied loads and boundary conditions, or element properties.

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RBAR1 MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and RBAR1 is the selected type. This form is used to create an MSC Nastran RBAR1 Bulk Data entry.

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Chapter 2: Building A Model 53 Finite Elements

RTRPLT1 MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and RTRPLT1 is the selected type. This form is used to create an MSC Nastran RTRPLT1 Bulk Data entry.

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Patran Interface to MSC Nastran Preference Guide Finite Elements

RJOINT MPCs

This subordinate MPC form appears when the Define Terms button is selected on the Finite Elements form and RJOINT is the selected type. This form is used to create an MSC Nastran RJOINT Bulk Data entry.

Superelements In superelement analysis, the model is partitioned into separate collections of elements. These smaller pieces of structure, called Superelement, are first solved as separate structures by reducing their stiffness matrix, mass matrix, damping matrix, loads and constraints to the boundary nodes and then combined to

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Chapter 2: Building A Model 55 Finite Elements

solve for the whole structure. The first step in creating a superelement is to create a Patran group (using Group/Create) that contains the elements in the superelement. This group is then selected in the Finite Elements application on the Create/ Superelement form.

Entry Superelement List

Main Index

Description List of existing superelements.

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Entry

Main Index

Description

Element Definition Group

The group containing all the elements that define a superelement. Note that the group must contain elements not just nodes. If a group does not contain elements, it will not show up in the Element Definition Group listbox.

Select Boundary Nodes...

Brings up an optional subordinate form that allows a user to select boundary nodes of the superelement. By default, the common nodes between the elements in the group and the rest of the model are selected as the boundary nodes.

Chapter 2: Building A Model 57 Finite Elements

Select Boundary Nodes

Entry

Main Index

Description

Select Boundary Nodes

Allows for manual selection of boundary nodes.

Add

Add selected nodes to the Selected Boundary Nodes box.

Remove

Remove selected nodes from the Selected Boundary Nodes box.

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Patran Interface to MSC Nastran Preference Guide Material Library

2.6

Material Library The Materials form appears when the Material toggle, located on the Patran application selections, is chosen. The selections made on the Materials menu will determine which material form appears, and ultimately, which Nastran material will be created. The following pages give an introduction to the Materials form and details of all the material property definitions supported by the Nastran Preference. Only material records that are referenced by an element property region or by a laminate lay-up are translated. References to externally defined materials result in special comments in the input Nastran file, e.g., materials that property values that are not defined in Patran. The forward translator performs material type conversions when needed. This applies to both constant material properties and temperature-dependent material properties. For example, a three-dimensional orthotropic material that is referenced by CHEXA elements is converted into a three-dimensional anisotropic material.

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Chapter 2: Building A Model 59 Material Library

Materials Application Form This form appears when Materials is selected on the main menu. The Materials form is used to provide

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Patran Interface to MSC Nastran Preference Guide Material Library

options to create the various Nastran materials.

Entry

Main Index

Description

Object

This toggle defines the basic material directionality and can be set to Isotropic, 2D Orthotropic, 3D Orthotropic, 2D Anisotropic, 3D Anisotropic, Fluid, Cohesive, or Composite. For Explicit Nonlinear additional materials can be defined.

Existing Materials

Lists the existing materials with the specified directionality.

Chapter 2: Building A Model 61 Material Library

Entry

Description

Material Name

Defines the material name. A unique material ID will be assigned during translation.

Description

Describes the material that is being created.

Input Properties...

Generates a form that is used to define the material properties. See Material Input Properties Form, 61

Change Material Status...

Generates a form that is used to indicate the active portions of the material model. By default, all portions of a created material model are active.

Material Input Properties Form The Input Properties form is the form where all constitutive material models are defined for each material created. Multiple constitutive models can be created for each material created by pressing the Apply button on the main Materials form with the proper widgets set on this form. Multiple constitutive models of the same type are not allowed. The list of existing constitutive models are shown in the bottom list box. A list of valid constitutive models is given in the table below.

Main Index

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Entry

Description

Constitutive Model

Set the Constitutive Model here. Press the Apply button on the main Materials application form to create a constitutive model for the given material. Multiple constitutive models can be created for the same material.

Property Name and Value

Enter the property values in the databoxes. If a value can be temperature, model, strain rate, or strain dependent, a separate listbox will appear to select a field. These fields must be created in the Fields application as Material type fields.

Current Constitutive Models

This is a list of current constitutive models. Use the Change Material Status button to turn them on/off from translation into the Nastran input deck.

Material Constitutive Models The following table outlines the options when Create is the selected Action. Object Isotropic

Option 1

Option 2

Option 3

Option 4

Option 5

• Linear Elastic • Nonlinear Elastic • Hyperelastic • Nearly

• Test Data

• Mooney Rivlin

Incompressible

Order: 1 2 3

• Coefficients

• Mooney Rivlin • Ogden • Foam

Order: 1

• Arruda-Boyce

2

• Gent

3 4 5

Main Index

Chapter 2: Building A Model 63 Material Library

Object

Option 1

Option 2

Option 3 • User Sub.

(UELASTOME R)

Option 4

Option 5

• Foam_Invariants 0 • Foam_Principals • Foam_Invariants

(Dev. Split) • Foam_Principals

(Dev. Split) • Rubber_Invariant

Based • Rubber_Principal

Stretch • Elastoplastic • Stress/Strain

Curve

• von Mises

• Isotropic

• Tresca

• Kinematic

• Mohr-Coulomb

• Combined

• Drucker-Prager • Parabolic Mohr-

Colomb • Buyukozturk

Concrete

• Isotropic • Kinematic

Linear

• Combined

• Cowper-

• Oak Ridge

National Labs • 2-1/4 Cr-Mo

ORNL • Reversed

Plasticity ORNL • Fully Alpha

Reset ORNL • Generalized

Plasticity • None

• Power Law • Power Rate Law • Johnson-Cook • Kumar

Main Index

• Piecewise

Symonds

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Object

Option 1

Option 2 • Hardening

Slope

Option 3

Option 4

• von Mises

• Isotropic

• Tresca

• Kinematic

• Mohr-Coulomb

• Combined

Option 5

• Drucker-Prager • Perfectly

Plastic

• Parabolic Mohr-

• None

Colomb

• Piecewise

Linear

• Buyukozturk

• Cowper-

Concrete

Symonds

• Oak Ridge

National Labs • 2-1/4 Cr-Mo

ORNL • Reversed

Plasticity ORNL • Fully Alpha

Reset ORNL • Generalized

Plasticity • Rigid Plastic

• None

• Power Law • Power Rate Law • Johnson-Cook • Kumar

PiecewiseLinear

• Failure

• n/a • Hill • Hoffman • Tsai-Wu • Maximum Strain

Main Index

Piecewise Linear CowperSymonds

Chapter 2: Building A Model 65 Material Library

Object

Option 1

Option 2

• Failure1/2/3 • Maximum

Stress • Maximum

Strain • Hoffman

Option 3

Option 4

• No Progressive • Standard • Gradual Selective • Immediate Selective

• Hill • Tsai-Wu • Hashin • Puck • Hashin-Tape • Hashin-Fabric • User Sub.

UFAIL • Creep

• Tabular Input • Creep Law 111 • Creep Law 112 • Creep Law 121 • Creep Law 122 • Creep Law 211 • Creep Law 212 • Creep Law 221 • Creep Law 222 • Creep Law 300 • User Sub.(CRPLAW) • MATVP

• Hypoelastic

• Isotropic

• Gradient Only

• User Defined

• Gradient and Rotation • Gradient and Stretch Ratio • All Input • All Input (mid increment) • All Input (end increment)

Main Index

Option 5

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Object

Option 1 • User

Defined

Option 2

Option 3

Option 4

• User Defined

• Gradient Only

• Isotropic

• Gradient and Rotation

Option 5

• Gradient and Stretch Ratio • All Input • All Input (mid increment) • All Input (end increment) • Viscoelastic • No Function • Williams-Landel-Ferry • Power Series Expansion • Stress-Life (SN) and Strain Life (eN), Spot Weld (Top and Bottom Sheet), Seam Weld (Stiff and Flexible)

2D Orthotropic

• Derived

• Ferrous (99)

• Range

• Standard

• Aluminium

• Amplitude

Parameters • Bastenaire

Parameters • Tabular

(100) • Titanium (300) • Other (0) • None

• MMPDS

• Linear Elastic • Failure

• Stress

• n/a

• Strain

• Hill • Hoffman • Tsai-Wu • Maximum Strain

• Failure1/2/3 • See Isotropic Entry

Main Index

• None

• Constant

Mean • Constant

R-Ratio • Constant

Life • None

Chapter 2: Building A Model 67 Material Library

Object

Option 1

Option 2

• Elastoplastic • Stress/Strain

Curve

Option 3

Option 4

Option 5

• von Mises

• Isotropic

• Tresca

• Kinematic

Linear

• Mohr-Coulomb

• Combined

• Cowper-

• Drucker-Prager

• Piecewise

Symonds

• Oak Ridge

National Labs • 2-1/4 Cr-Mo

ORNL • Reversed

Plasticity ORNL • Fully Alpha

Reset ORNL • Generalized

Plasticity • Hardening

Slope

• von Mises

• Isotropic

• Tresca

• Kinematic

• Mohr-Coulomb

• Combined

• Drucker-Prager • Perfectly

• von Mises

Plastic

• Oak Ridge

National Labs • 2-1/4 Cr-Mo

ORNL • Reversed

Plasticity ORNL • Fully Alpha

Reset ORNL • Generalized

Plasticity • Creep

• MATVP

• Viscoelastic • See Isotropic Entry

3D Orthotropic

• Linear Elastic • Elastoplastic • See 2D Orthotropic Entry • Failure1/2/3 • See 2D Orthotropic Entry • Creep

Main Index

• See 2D Orthotropic Entry

• None

• Piecewise

Linear • Cowper-

Symonds

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Object

Option 1

Option 2

Option 3

Option 4

Option 5

• Viscoelastic • See Isotropic Entry

2D Anisotropic

• Linear Elastic • Elastoplastic • See 2D Orthotropic Entry • Failure

• See Isotropic Entry

• Failure1/2/3 • See Isotropic Entry - progressive failure not supported

3D Anisotropic

• Linear Elastic • Elastoplastic • See 2D Orthotropic Entry • Failure1/2/3 • See 2D Orthotropic Entry - progressive failure not supported • Creep

Fluid

• Linear Elastic

Cohesive

• Bilinear

• See Isotropic Entry • Secant

• Exponential • Secant • Linear-

• Secant

• No

• Automatic

• Yes

• User Defined

• No

• Automatic

• Yes

• User Defined

• Yes

• Automatic

Exponential • User Sub.

• Secant

• No

• None

• Yes

• Laminate • Rule of Mixtures • HAL Cont. Fiber • HAL Disc. Fiber • HAL Cont. Ribbon • HAL Disc. Ribbon • HAL Particulate • Short Fiber 1D • Short Fiber 2D

Additional materials for Explicit Nonlinear (SOL 700) are listed in the following table.

Main Index

• Keep • Keep

• User Defined

(UCOHESI VE) Composite

• Keep

• Keep

Chapter 2: Building A Model 69 Material Library

Object Isotropic

Option 1 • Linear Elastic

Option 2 • Linear Elastic

(MAT1) • Elastoplastic

• Plastic

Option 3 •

Option 4

Option 5

Solid

• Fluid • Bilinear

Kinematic(MAT 3) • Iso.Elastic

Plastic(MAT12) • Rate Dependent

(MAT19) • Piecewise Linear

(MAT24)

• Biliear

• Cowper Symonds

• Linearized

• General

• Table • Rate Sensitive

• Powerlaw

(MAT64) • Resultant (MAT28) • Shape Memory (MAT30) • With Failure (MAT13) • Power Law (MAT18) • Ramberg-Osgood (MAT80) • Hydro (MAT10)

• Linearized

• Viscoelastic

• Viscoelastic (MAT6)

• Rigid

• Material Type 20 • No Constraints • Global Directions • Local Directions • MATRIG (Rigid

• Geometry Body Properties) • Defined

• No Constraints • Global Directions • Local Directions

• Johnson Cook

• Material Type 15 • No iteractions • Accurate

• Minimum Pressure • No Tension, Min. Stress • No Tension, Min. Pressure

• Rubber

• Frazer Nash

(MAT31)

Main Index

• Coefficient

• Respect

• Least Square Fit

• Ignore

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Object

Option 1

Option 2

Option 3

Option 4

Option 5

• Blatz-Ko (MAT7) • General Viscoelastic (MAT76) • Cellular Rubber (MAT87) • Mooney Rivlin

(MAT27)

• Coeff. • Least Square

• Arruda-Boyce

(MAT127) • Hyperelastic

(MAT77) • Simplified

• Coefficients • Least Square Fit 1/2/3 • Tension-

Compresion Load • Compression Load

• True Strain • Engineering

Strain Rate

• Simple

Average • 12 Point

Average

• Tension-

Compression Identical • Foam

• Soil and Foam

• Active (MAT14)

• Allow Crushing

(MAT5/14)

• Inactive (MAT 5)

• Reversible

• Bulk Viscosity

• No Tension

• Low Density

Urethane (MAT57) • Fu Chang Foam

Inactive

• Maintain Tension

• Bulk Viscosity

Active

(MAT83) • Low Density

Urethane (MAT57)

• Bulk Viscosity

Inactive • Bulk Viscosity

• No Tension • Maintain

Tension

Active

• With

Relaxati on curve • No

Relaxati on Curve • Viscous Foam (MAT62) • Crushable (MAT63) • Elastoviscoplatic • With Damage

(MAT81)

Main Index

• Strain Damage

• Bilinear

• Orthotropic

• Linearized

• RCDC

• Table

• Cowper

Symond s • General

Chapter 2: Building A Model 71 Material Library

Object

Option 1 • Discrete Beam

Option 2

Option 3

Option 4

• Nonlinear Elastic Discrete Beam (MAT67) • Nonlinear Plastic Discrete Beam (MAT68) • Side Impact Dummy (SID) Damper Discrete Beam (MAT69) • Hydraulic Gas Damper Discrete Beam (MAT70) • Cabel Discrete Beam (MAT71) • Elastic Spring Discrete Beam (MAT74) • Elastic 6 DOF Spring Discrete Beam (MAT93) • Inelastic Spring Discrete Beam (MAT94) • Inelastic 6 DOF Srping Discrete Beam (MAT95) • General Joint Discrete Beam (MAT97)

• Spring Damper • Nonlinear 6

• Follow Loading Curve DOF Discrete • Follow Unloading Curve Beam (MAT119) • Follow Unloading Stiffness • General • Follow Quadratic Unloading Nonlinear 1 DOF Discrete Beam (MAT121) • Elastic Spring (MATDS01) • Viscous Damper (MATDS02) • Elastic Spring (MATDS03) • Nonlinear Elastic Spring (MATDS04) • Nonlinear Viscous Damper (MATDS05) • General Nonlinear Spring (MATDS06) • Spring Maxwell (MATDS07) • Inelastic Spring (MATDS08) • Tri-linear Degrading (MATDS13) • Squat Shear Wall (MATDS14) • Muscle (MATDS15)

• Seat Belt

• Seat Belt (MATB01)

• Spotweld

• MATDSW1

• DF

• MATDSW2

• DFRES • DFRESNF • DFRESNFP

• MATDSW3

Main Index

• DFSTR

Option 5

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Object

Option 1

Option 2

Option 3

• MATDSW4

• DFRATE

• MATDSW5

• DFNS

Option 4

Option 5

• DFSIF • DFSTRUC

2D Orthotropic

• Glass

• Laminated Glass

(Laminated) • Composite

(MAT32) • Enh. Composite

Damage

• Glass • Polymer • Tsai-Wu Theory • Chang-Chang Theory

• Linear Elastic

• Linear Elastic (MAT2)

• Composites

• Composites and

and Fabrics

Fabrics (MAT58)

• Zero

• 0.0

• One

• 1.0

• Two

• -1.0

• Three

3D Orthotropic

• Honeycomb

• Composite

•

Composite Honeycomb (MAT26)

• Bulk Viscosity Inactive • Bulk Viscosity Active

• Composite Damage (MAT22) • Composite

• Faceted Failure (MAT59) • Ellipsoidal

• Linear Elastic

• Linear Elastic (MAT2)

• Modified

•

Honeycomb

Modified Honeycomb (MAT126)

• Bulk Viscosity

Inactive

• LCA .LT. 0

• Zero

• LCA .GT. 0

• One

• Bulk Viscosity

• Two

Active 2D Anisotropic

• Viscoplastic

• Viscoplastic

• Shell

(MAT103)

3D Anisotropic

• Manual Entry

• Linear Elastic

• Linear Elastic (MAT2)

• Viscoplastic

• Viscoplastic

• Brick

(MAT103) • Linear Elastic

Main Index

• From Curve

• Linear Elastic (MAT2)

• From Curve • Manual Entry

Chapter 2: Building A Model 73 Material Library

Linear Elastic The Input Properties form displays the following for linear elastic properties. The translator produces MAT1 entries for isotropic materials, MAT8 entries for 2D orthotropic materials, MAT3 entries using axisymmetric solid elements or MAT9 entries using 3D solid elements (CHEXA, CPENTA, CTETRA) for 3D orthotropic materials, MAT2 entries for 2D plane stress - 2D anisotropic materials, and MAT9 entries for 3D anisotropic materials. For temperature dependencies, the corresponding MATTi entries are written referencing TABLEMi entries. Temperature dependency is defined using material fields defined under the Fields application. SOL 600 jobs using 3D Orthotropic material the MATORT entry is written SOL 400 jobs using 3D Orthotropic MATORT materials are shown for selection when setting up the UDS Map (See User Defined Services, 367). If UDS Map exists for a 3D Orthotropic MATORT material, the MATUDS entry is written to activate user subroutine orient in conjunction with MATORT. . Isotropic

Description

Elastic Modulus

Elastic modulus, E, (Young’s modulus). Can be temperature dependent.

Poisson Ratio

Poisson’s ratio (NU). Can be temperature dependent. Should be between -1.0 and 0.5.

Shear Modulus

Shear modulus (G). Can be temperature dependent.

Density

Density (RHO). Can be temperature dependent.

Thermal Expansion Coefficient

Thermal coefficient of expansion (A). Can be temperature dependent.

Structural Damping Coefficient

Structural damping coefficient (GE). Can be temperature dependent.

Reference Temperature

Reference temperature (TREF).

2D/3D Orthotropic

Description

Elastic Modulus ii

Modulus of elasticity in 1-, 2-, and 3-directions. Can be temperature dependent.

Poisson Ratio ij

Poisson’s ratio for uniaxial loading in the three different directions. Can be temperature dependent.

Shear Modulus ij

In-plane and transverse shear moduli in ij planes. Can be temperature dependent.

Density

Density (RHO). Can be temperature dependent.

Thermal Expansion Coefficient ii Thermal coefficients of expansion in the three directions. Can be temperature dependent.

Main Index

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2D/3D Orthotropic

Description

Structural Damping Coefficient

Structural damping coefficient (GE). Can be temperature dependent.

Reference Temperature

Reference temperature (TREF).

2D/3D Anisotropic

Description

Stiffness ij

Elements of the 6x6 symmetric material property matrix in the material coordinate system. Can be temperature dependent.

Density

Density (RHO). Can be temperature dependent.

Thermal Expansion Coefficient ij Thermal coefficients of expansion. Can be temperature dependent.

Main Index

Structural Damping Coefficient

Structural damping coefficient (GE). Can be temperature dependent.

Reference Temperature

Reference temperature (TREF).

Chapter 2: Building A Model 75 Material Library

Nonlinear Elastic The Input Properties form displays the following for nonlinear elastic properties. Use this form to define the nonlinear elastic stress-strain curve on the MATS1 entry. A stress-strain table defined using the Fields application can be selected on this form. Based on this information the translator will produce MATS1 of type NLELAST and TABLES1 entries. This is used primarily for SOL 106 and 129. This option is not supported by SOL 600. Use an elastoplastic constitutive model instead.

Main Index

Isotropic

Description

Stress/Strain Curve

Defines the nonlinear elastic stress-strain curve. You must select a field from the listbox. It can be strain and/or temperature dependent. Tabular definition of the stress-strain curve via the Fields application using a material field of strain should follow the specifications as outlined by Nastran. The first point of the material field should be the origin and the second point must be at the initial yield point. This material curve is elastic, meaning that in both loading and unloading the material behavior follows the stress-strain curve as defined. It is not recommended that both nonlinear elastic and elastoplastic constitutive models be active or defined for the same material. For work hardening, use the Elastoplastic constitutive model. See the Nastran Quick Reference Guide for more details.

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Hyperelastic The Input Properties form displays the following for hyperelastic properties. Use this form to define the data describing hyperelastic behavior of a material. This data is placed on MATHP and TABLES1 entries or on the MATHE entry for SOL 600. If you select Test Data as the Data Type, the Input Options form reverts to the form used for non-SOL 600 solutions and data is placed on a MATHP entry (Mooney-Rivlin strain energy model). To use test data for MATHE/SOL 600 runs, use the Experimental Data Fitting features under the Tools menu to determine the coefficients and enter them manually. Test Data - Mooney Rivlin

Description

Tension/Compression TAB1

All data provided must reference a strain dependent field defining the test data. Please refer to the Nastran Quick Reference Guide for descriptions of each of these tabular inputs.

Equibiaxial Tension TAB2 Simple Shear Data TAB3 Pure Shear Data TAB4 Pure Volume Compression TABD

If Coefficients is selected as the Data Type, use the form to describe the strain energy potential. The Mooney Rivlin model can be written out as a MATHP or MATHE entry for SOL 600. Make sure you use the one that is consistent with the solution to be run. Ogden, Foam, Arruda-Boyce, and Gent models are used for SOL 600 MATHE entries only. Mooney Rivlin (MATHP)

Description

Distortional Deformation Coefficients, Aij

Material constants related to distortional deformation. The Order of the Polynomical determines the number of coefficients required as input.

Volumetric Deformation Coefficients, Di

Material constants related to volumetric deformation. The Order of the Polynomial determines the number of coefficients required as input.

Density RHO

Defines the mass density which is an optional property.

Volumetric Thermal Expansion Coefficient AV Coefficient of volumetric thermal expansion.

Main Index

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Structural Damping Coefficient GE

Structural damping element coefficient.

Chapter 2: Building A Model 77 Material Library

Mooney Rivlin (MATHE)

Description

Strain Energy Function C10, C01, C11, C20, C30

Strain energy densities as a function of the strain invariants in the material. May vary with temperature via a defined material field. This option consolidates several of the hyperelastic material models, including Neo-Hookean (C10 only), Mooney-Rivlin (C10 & C01), and Full Third Order Invariant (all coefficients).

Density RHO

Defines the mass density

Thermal Expansion Coefficient

Defines the instantaneous coefficient of thermal expansion. This property is optional. May vary with temperature via a defined material field.

Bulk Modulus K

Defines the Bulk Modulus.

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Structural Damping Coefficient GE

Structural damping element coefficient.

Ogden

Description

Bulk Modulus K

Defines the Bulk Modulus.

Density RHO

Defines the material mass density.

Coefficient of Thermal Expansion

Defines the instantaneous coefficient of thermal expansion. This property is optional. May vary with temperature via a defined material field

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Modulus k

μk

in the Ogden equation. The number of

moduli required as input is dependent on the Order of the Polynomial. Exponent k

αk

in the Ogden equation. The number of

exponents required as input is dependent on the Order of the Polynomial.

Main Index

Foam

Description

Bulk Modulus K

Defines the Bulk Modulus.

Density RHO

Defines the material mass density.

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Foam

Description

Thermal Expansion Coefficient

Defines the instantaneous coefficient of thermal expansion. This property is optional. May vary with temperature via a defined material field

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Modulus n

un

in the Foam equation. The number of moduli

required as input is dependent on the Order of the Polynomial. Deviatoric Exponent n

αn

in the Foam equation. The number of

exponents required as input is dependent on the Order of the Polynomial. Volumetric Exponent n

βn

in the Foam equation. The number of

exponents required as input is dependent on the Order of the Polynomial.

Main Index

Chapter 2: Building A Model 79 Material Library

Arruda- Boyce

Description

NKT

Chain density times Boltzmann constant times temperature. May vary with temperature via a defined material field.

Chain Length

Average chemical chain cross length. May vary with temperature via a defined material field.

Bulk Modulus K

Defines the Bulk Modulus.

Density RHO

This defines the material mass density.

Thermal Expansion Coefficient

Defines the instantaneous coefficient of thermal expansion. This property is optional. May vary with temperature via a defined material field

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Gent

Description

Tensile Modulus

Defines standard tension modulus (E). May vary with temperature via a defined material field.

I 1*

Maximum 1st Invariant

Defines

*

I1 = I1 – 3

. May vary with

temperature via a defined material field. Bulk Modulus K

Defines the Bulk Modulus.

Density RHO

This defines the material mass density.

Coefficient of Thermal Expansion

Defines the coefficient of thermal expansion.

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

If you select User Sub. (UELASTOMER) as the Data Type, use the form to describe the User Strain Energy Function (Model = GHEMi) (SOL 400 only) and data is placed on a MATHE entry. GHEM1, GHEM2, GHEM3, GHEM4, GHEM5 and GHEM6 models are used for SOL 400 MATHE entries only. This material is shown for selection when setting up the UDS Map (See User Defined Services, 367). If UDS Map exists, the MATUDS entry is written to activate user subroutine uelastomer in conjunction with MATHE.

Main Index

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Foam-Invariants (GHEM1) / Foam-Principals (GHEM2) / Foam-Invariants (Dev. Split) (GHEM3) / Foam-Principals (Dev. Split) (GHEM4) / RubberInvariant Based (GHEM5) / Rubber-Principal Stretch (GHEM6)

Description

Bulk Modulus K

Defines the Bulk Modulus.

Density RHO

Defines the mass density

Thermal Expansion Coeff

Defines the coefficient of thermal expansion.

Reference Temp. TREF

Defines the reference temperature for the thermal expansion coefficient.

Structural Damp. Coeff. GE

Defines the structural damping coefficient.

Main Index

Chapter 2: Building A Model 81 Material Library

Elastoplastic The Input Properties form displays the following for elastoplastic properties. Use this form to define the data describing plastic behavior of a material. The stress-strain curve data is input via a material property field of strain and placed on MATS1 and TABLES1 entries. The data input should be the true equivalent stress vs. equivalent total strain. Other options are placed on the MATEP entry and are valid only for SOL 400 & 600. Note that the existence of both an elastoplastic and nonlinear elastic constitutive models in the same material is not recommended. Stress/Strain Curve

Description

Yield Function

Yield function (YF) criterion: von Mises, Tresca, Mohr-Coulomb, & DruckerPrager supported on MATS1 entry. All others are for SOL 600 and placed on the MATEP entry. SOL 400 only supports von Mises.

Hardening Rule

Hardening Rule (HR). These are Isotropic, Kinematic, and Combined isotropic and kinematic and are placed on the MATS1 entry or MATEP entry depending on solution sequence and yield function selected. Hardening rules Power Law, Rate Power Law, Johnson-Cook, Kumar are available when no Yield Function is specified. This is used for SOL 600 only on MATEP entry.

Strain Rate Method

Selects an option for strain-rate dependent yield stress used in SOL 600. Cowper-Symonds requires input of Denominator C and Inverse Exponent P.

Stress/Strain Curve

This data must reference a strain dependent field. It can also be temperature and strain rate dependent. LIMIT1 in MATS1 determined from supplied tabular field of stress-strain curve. Data is placed on TABLES1 entry.

Internal Friction Angle

Defined for Mohr-Coulomb and Drucker-Prager yield function placed on the MATS entry LIMIT2.

Yield Point

Initial yield stress.

Stress at Yield

Main Index

Beta

Parameter beta for parabolic Mohr-Coulomb or Buyukozturk concrete models. Placed on the MATEP entry.

10th Cycle Yield Stress

Equivalent 10th cycle tensile yield stress for Oak Ridge National Labs models (ORNL). Placed on the MATEP entry.

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Stress/Strain Curve

Description

Denominator C

Constants for the Cowper-Symonds strain rate method.

Inverse Exponent P Coefficient A / B / C / Bi Exponent M / N initial Strain Rate Room Temperature

Coefficient and exponent data for Power Law, Rate Power Law, Johnson-Cook, and Kumar hardening rules. Additional data input for the Johnson-Cook hardening rule.

Melt Temperature

Hardening Slope

Description

Yield Function

Yield function (YF) criterion: von Mises, Tresca, Mohr-Coulomb, & DruckerPrager supported on MATS1 entry.

Main Index

Hardening Rule

Hardening Rule (HR). These are Isotropic, Kinematic, and Combined isotropic and kinematic and are placed on the MATS1 entry.

Strain Rate Method

No strain rate methods are available for the Hardening Slope data.

Hardening Slope

Work hardening slope (H) - slope of stress versus plastic strain. Defined in units of stress. For an elastic-perfectly plastic case, use the Perfectly Plastic data input option.

Internal Friction Angle

Defined for Mohr-Coulomb and Drucker-Prager yield function placed on the MATS entry LIMIT2.

Yield Point

Initial yield stress.

Perfectly Plastic

Description

Yield Function

See the Stress / Strain Curve table above. All options are identical except there must be a yield function selected.

Hardening Rule

None are available since no hardening is possible for a perfectly plastic material.

Chapter 2: Building A Model 83 Material Library

Perfectly Plastic

Description

Strain Rate Method

Piecewise linear or Cowper-Symonds are available.

Yield Point

Initial yield stress.

All other data input is described in the Stress/Strain Curve table above.

Rigid Plastic

Description

Yield Function

No yield functions are available as the material is defined as rigid and then plastic, so no yield is possible.

Hardening Rule

See the Stress / Strain Curve table above. Valid options are the Power Law, Power Rate Law, Johnson-Cook, Kumar, and Piecewise Linear.

Strain Rate Method

Piecewise linear or Cowper-Symonds are available only if the Piecewise Linear hardening rule is selected.

Stress/Strain Curve

Necessary only when not using one of the power law hardening rules (Piecewise-Linear). This data must reference a strain dependent field. It can also be temperature and strain rate dependent. LIMIT1 in MATS1 determined from supplied tabular field of stress-strain curve. Data is placed on TABLES1 entry.

All other data input is described in the Stress/Strain Curve table above. Rigid Plastic is only used in SOL 600 and only for isotropic materials. See the Nastran Quick Reference Guide for more information about the necessary data for MATS1 and MATEP entries.

Main Index

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Failure The Input Properties form displays the following for failure material models. Note that this failure model is for non-SOL 400/600/700 solutions. See Failure 1/2/3 for SOL 400/600/700. No Composite Failure Theory

Description

Tension Stress Limit

Stress limits for tension, compression, and shear used to compute margins of safety in certain elements. They have no effect on the computational procedures.

Compression Stress Limit Shear Stress Limit

Failure criteria for the isotropic and two-dimensional orthotropic and anisotropic materials appear in the ST, SC, and SS fields on MAT1 and MAT2 entries and the Xt, Xc, Yt, Yc, and S fields on the MAT8 entry. Composite Failure Theory:

Description

Hill, Hoffman, Tsai-Wu, Maximum Failure Limits

For 2D orthotropic on the MAT8 entry, the limits can be defined as stress or strain allowables. This is not applicable to isotropic and anisotropic materials.

Tension Stress Limit

Stress limits for tension, compression, and shear are the same as those defined for non-composite failure.

Compression Stress Limit Shear Stress Limit Bonding Shear Stress Limit

Allowable shear stress of the bonding material. SB field on the PCOMP entry.

Failure criteria for the isotropic and two-dimensional orthotropic and anisotropic materials appear in the ST, SC, and SS fields on MAT1 and MAT2 entries and the Xt, Xc, Yt, Yc, and S fields on the MAT8 entry unless composites are being used in which case the data is written to the PCOMP entry as necessary.

Main Index

Chapter 2: Building A Model 85 Material Library

Failure 1, Failure 2, Failure 3 The Input Properties form displays the following for failure material models used in SOL 400 and 600. Solution sequences other than SOL 400/600/700 should use the Failure constitutive model above instead. Up to three failure constitutive models can be defined for any one material. Failure 1 must exist in order for Failure 2 and 3 to be recognized and translated into the proper MATF and MATTF entries. Temperature dependent properties as defined by material fields are translated onto the MATTF entry. Note also that only Failure 1 allows for definition of progressive failure. Failure models 2 and 3 take on whatever progressive failure is defined in Failure 1. Different failure criterion may exist between all three in the same material definition. The table below outlines the allowable properties. All values are real, 0.0, or left blank with no defaults unless otherwise indicated. Which properties are available is dependent on the Failure Criterion selected. The following Failure Criteria are available: • Maximum Stress • Maximum Strain • Hill • Hoffman • Tsai-Wu • Hashin • Puck • Hashin-Tape • Hashin-Fabric • User Sub. UFAIL

If you select User Sub. UFAIL as the Failure Criteria, the form with the Progressive Failure Option and no properties displays. Use the form to specify the Progressive Failure Option. The data is placed on a MATF entry. For SOL 400 jobs, this material is shown for selection when setting up the UDS Map (See User Defined Services, 367). If UDS Map exists, the MATUDS entry is written to activate user subroutine ufail (if Progressive Failure Option is set to None) / uprogfail (if Progressive Failure Option is set to Progressive Failure / Gradual / Immediate) in conjunction with MATF.

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Property

Description

Progressive Failure Options

Progressive failure options are None, standard Progressive Failure, Gradual or Immediate selective progressive failure for SOL 600. SOL 400 does not support progressive failure models and will ignore this setting if set to anything other than None. Only failure indices are computed when no progressive failure is specified. Anisotropic materials do not support progressive failure.

Tension Stress Limit X / Y /Z Tension Strain Limit X / Y / Z

Tension, compression, and shear stress or strain limits used in the Maximum Stress or Strain, Hill, Hoffman, and Tsai-Wu failure criteria.

Compression Stress Limit X / Y / Z Compression Strain Limit X / Y / Z Shear Stress Limit XY / YZ / ZX Shear Strain Limit XY / YZ / ZX Shear Stress Bond (SB)

Allowable shear stress of bonding material between layers for composites only. This is used in SOL 600 only and is ignored for SOL 400.

Failure Index

Failure index used for Hill, Hoffman, and Tsai-Wu criteria.

Interactive Strength XY / YZ / ZX

Interactive strength constants for specified plane used in the Tsai-Wu criterion.

Max Fiber / Matrix Tension Max Fiber / Matrix Compression

Definable stress limits for Hashin, Puck, HashinTape, and Hashin-Fiber criteria.

Max Tape Fiber Tension Max Tape Fiber Compression Max 1st Fiber Tension / Compression Max 2nd Cross Fiber Tension / Compression Max Thickness Tension Max Thickness Compression

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Layer Shear Strength Transverse Shear Strength YZ / ZX

Shear stress limits for Hashing, Puck, Hashin-Tape, and Hashin-Fiber criteria.

Slope P12C / P12T / P23C / P23T of Fracture Envelope

Slopes of the failure envelope used in Puck failure criterion.

Chapter 2: Building A Model 87 Material Library

Property

Description

Deactivate Tension X / Y/ Z Deactivate Compress X / Y / Z Deactivate Shear XY / YZ / ZX

If any value other than blank or 0.0 is entered for progressive failure options Gradual and Immediate, failed elements are deactivated (placed ICi fields in MATF entry). See the Nastran Quick Reference Guide for information.

Deactivate Elements Deactivate Fiber / Matrix Tension Deactivate Fiber /Matrix Compression Deactivate Matrix Tension Deactivate Matrix Compression Residual Stiffness Factor Matrix Compression Factor Shear Stiffness Factor E33 Fiber Failure Factor Shear Fiber Failure Factor

Main Index

Reduction fractions or factors. Values can be between 0.0 and 1.0. Used only for Gradual or Immediate progressive failure modes (placed on Ai fields in MATF entry). See the Nastran Quick Reference Guide for more information.

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Creep The Input Properties form displays the following for creep models. Tabular Input

Description

Data defined by the use of this form to define the primary stiffness, primary damping, and secondary damping for a creep model with tabular input appears on the CREEP entry for non-SOL 600 runs. Only isotropic materials use this data input method. Creep Law ijk

Description

Use this form to define the coefficients for one of many empirical creep models available appears on the CREEP entry for non-SOL 600 runs. Only isotropic materials use this creep definition. User Sub.(CRPLAW) Use this form to define the creep law using user subroutine crplaw for SOL 400 runs. This data is written to the MATVP entry in primary format. For SOL 400 jobs, this material is shown for selection when setting up the UDS Map (See User Defined Services, 367). If UDS Map exists, the MATUDS entry is written to activate user subroutine crplaw in conjunction with MAT1. MATPV

Description

Use this form to define either the coefficients and exponents for creep model or provide tabular field data to define Temperature vs. Creep Strain, Creep Strain Rate vs. Stress, Strain Rate vs. Creep Strain, or Time vs. Creep Strain in SOL 600 runs. This data is written to the MATVP entry. If tabular data is provided, this data is written to TABLEM1 entries. It is not recommended to mix the exponents and coefficients and tabular data. Use one or the other.

Main Index

Chapter 2: Building A Model 89 Material Library

Hypoelastic The Input Properties form displays the following to define user-defined generic material properties for hypoelastic material models in SOL 400 only. The data is placed on MATUSR entry. This material is shown for selection when setting up the UDS Map (See User Defined Services, 367). If UDS Map exists, the MATUDS entry is written to activate user subroutine hypela2 in conjunction with MATUSR. Property

Description

Coordinate System (IPREF)

Coordinate System (IPREF) options are Isotropic and User Defined

Kinematic Flag (IKINEM)

Kinematic Flag (IKINEM) options are Gradient Only, Gradient and Rotation, Gradient and Stretch Ratio, All Input, All Input (mid increment) and All Input (end increment)

Density

Density (RHO). Can be temperature dependent.

Thermal Expansion Coeff

Thermal coefficient of expansion (A1). Can be temperature dependent. Not show if coordinate system is User Defined.

Thermal Expansion Coeff (A1)

Thermal coefficient of expansion (A1). Can be temperature dependent. Not show if coordinate system is Isotropic.

Thermal Expansion Coeff (A2)

Thermal coefficient of expansion (A2). Can be temperature dependent. Not show if coordinate system is Isotropic.

Thermal Expansion Coeff (A3)

Thermal coefficient of expansion (A3). Can be temperature dependent. Not show if coordinate system is Isotropic.

Reference Temperature

Reference temperature (TREF).

Structural Damping Coeff

Structural damping coefficient (GE). Can be temperature dependent.

Tension Stress Limit

Stress limits for tension, compression, and shear used to compute margins of safety in certain elements. They have no effect on the computational procedures.

Compression Stress Limit Shear Stress Limit

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User Defined The Input Properties form displays the following to define user-defined generic material properties for user defined material models in SOL 400 only. The data is placed on MATUSR entry. This material is shown for selection when setting up the UDS Map (See User Defined Services, 367). If UDS Map exists, the MATUDS entry is written to activate user subroutine umat in conjunction with MATUSR. Property

Description

Coordinate System (IPREF)

Coordinate System (IPREF) options are Isotropic and User Defined

Kinematic Flag (IKINEM)

Kinematic Flag (IKINEM) options are Gradient Only, Gradient and Rotation, Gradient and Stretch Ratio, All Input, All Input (mid increment) and All Input (end increment)

Density

Density (RHO). Can be temperature dependent.

Thermal Expansion Coeff

Thermal coefficient of expansion (A1). Can be temperature dependent. Not show if coordinate system is User Defined.

Thermal Expansion Coeff (A1)

Thermal coefficient of expansion (A1). Can be temperature dependent. Not show if coordinate system is Isotropic.

Thermal Expansion Coeff (A2)

Thermal coefficient of expansion (A2). Can be temperature dependent. Not show if coordinate system is Isotropic.

Thermal Expansion Coeff (A3)

Thermal coefficient of expansion (A3). Can be temperature dependent. Not show if coordinate system is Isotropic.

Reference Temperature

Reference temperature (TREF).

Structural Damping Coeff

Structural damping coefficient (GE). Can be temperature dependent.

Tension Stress Limit

Stress limits for tension, compression, and shear used to compute margins of safety in certain elements. They have no effect on the computational procedures.

Compression Stress Limit Shear Stress Limit

Main Index

Chapter 2: Building A Model 91 Material Library

Viscoelastic The Input Properties form displays the following for viscoelastic models. This material model is only used in SOL 600 runs and all data is placed on the MATVE, MATTVE entries. Linear elastic or hyperelastic constitutive models for isotropic or anisotropic materials must exist in addition to the viscoelastic model.

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Stress-Life (SN) and Strain Life (eN), Spot Weld (Top and Bottom Sheet), Seam Weld (Stiff and Flexible) These constitutive models are used for defining fatigue material properties in order to run an MSC Nastran Embedded Fatigue analyses using statics (SOL 101), normal modes (SOL 103), modal transient response (SOL 112), and modal or direct frequency response (SOLs 111 or 108). All parameters defined here are placed on the MATFTG bulk data entry. With the Stress-Life (SN) constitutive model you can: • Derive S-N curves by specifying the type of metal, the ultimate tensile strength (UTS), and

Young’s Modulus (defined in the Linear constitutive model) (SOL 101/103/112 only) • Enter standard parameters to define an S-N curve (All SOLutions) • Enter Bastenaire parameters to define an S-N curve (SOLs 101/103/112 only) • Tabularly define multiple S-N curves by the selection of a pre-defined field. See Fields Create (Material Property, Tabular Input) (Ch. 6) in the Patran Reference Manual). One or more tabular

S-N curves can be defined that were derived from either constant mean stress or constant RRatio (minimum stress/maximum stress). The fields must be of type Life(N) as the independent variable. Also Haigh curves can be defined using the same mechanism where each curve is derived at a constant life value. Although the field in this case must also be of type Life(N), the yvalues are defined as mean stress vs. x-values of stress amplitude. The Value 1, 2, 3, etc. fields are used to input the constant mean, constant R-ratio, or constant life value at which the selected field (curve) was created. For SOLs 108 and 111, only a single tabular curve can be defined at a zero mean stress. • Enter MMPDS parameters to define S-N curve (SOLs 108 and 111 only)

With the Strain-Life (eN) constitutive model you can: • Derive strain-life (ε-N) and cyclic stress-strain (ε−σ) curves by specifying the type of metal, the

ultimate tensile strength (UTS), and Young’s Modulus (defined in the Linear constitutive model). (SOLs 101/103/112 only). • Enter standard parameters to define an the strain-life and cyclic stress-strain curves (All

SOLutions) With the Spot Weld Top and Bottom Sheet constitutive models (SOLs 101/103/112 only) you can: • Define Standard S-N curves for fatigue analysis of spot welds by specifying the type of metal

(steel or aluminum), the ultimate tensile strength (UTS), and Young’s Modulus (defined in the Linear constitutive model). • Manually enter standard parameters to define an S-N curve for the top and bottom sheets

manually • Please note the following: Three (3) S-N curves are allowed for fatigue analysis of spot welds.

One to define the spot weld nugget (center), and one each for the top and bottom sheet. If all locations use the same S-N curve, only the Stress-Life constitutive model needs to be defined. If the nugget and top/bottom sheet S-N curves differ, then it is necessary to define both the nugget as a standard Stress-Life constitutive model and the sheet(s) as a Spot Weld Top/Bottom Sheet

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Chapter 2: Building A Model 93 Material Library

constitutive model(s). If the top sheet is defined but not the bottom, or vice-versa, both take on the defined definition. If top and/or bottom are defined, but not a standard Stress-Life constitutive model for the nugget, then the nugget takes on the properties of the top sheet (or bottom if top is not defined). With the Seam Weld Stiff and Flexible constitutive models (SOLs 101/103/112 only) you can: • Define Standard S-N curves for fatigue analysis of seam welds by specifying the type of metal

(steel or aluminum), the ultimate tensile strength (UTS), and Young’s Modulus (defined in the Linear constitutive model). • Manually enter standard parameters to define an S-N curve for the stiff and flexible curves

manually • Please note the following: Two (2) S-N curves are allowed for fatigue analysis of seam welds.

One to define the stiff (bending ratio=0) and one for the flexible (bending ratio=1) properties. The analysis interprets between the two based on the actual bending ratio. If both are the same, only the Stress-Life constitutive model needs to be defined. If one is defined but not the other, then the undefined properties are taken from the standard Stress-Life constitutive model. If the stiff definition is defined but not the other, or vice-versa, but no standard Stress-Life constitutive model is defined, then the same properties are used for both. For all these methods of input, a conversion factor can be supplied. This conversion factor operates only on the stress parameters of the defined curves and is used to allow input of the parameters on these constitutive models in stress units other than the consistent model units. For example, if the consistent model units are in PSI (for stresses), then a factor off 145.0377 could be entered that would allow the stress parameters to then be entered in MPa. (Note that this only applies to parameters on these constitutive models and not for, say, the linear constitutive model where E is defined.) In order to run a successful MSC Nastran Embedded Fatigue analysis, at least one of the above constitutive model must be defined for the elements of interest. An output request for fatigue life must be made (see Output Requests, 478). An S-N (standard, spot or seam weld) or ε-N analysis must be turned on when setting up the analysis (see Solution Parameters, 312 for Linear Static, Normal Modes, or Transient Response). And a cyclic loading sequence must be defined (see Subcase Select, 515) above the subcase level. Optionally, various fatigue parameters can be defined as element properties such as surface finish (see Element Properties, 101) for shell and solid elements only. For more detail on how to set up and perform an MSC Nastran Embedded Fatigue analysis using Patran, please see the MSC Nastran Fatigue Analysis User’s Guidefor time domain SOLutions 101/103/112. See the MSC Nastran Embedded Vibration Fatigue User’s Guide for frequency domain solutions SOLs 108 and 111. For details on the MATFTG entry, please see the MATFTG (p. mmxciv) in the MSC Nastran Quick Reference Guide. Please note the following limitation: • MMPDS is only available for frequency domain SOLutions 108 and 111 and will fail if used

with time domain solutions.

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• MMPDS values A1-A4 must be entered in KSI units. Proper conversion is done internally to

MSC Nastran. The Conversion Factor (CNVRT) has no affect on these values and only affects Yield Stress (YS) and Ultimate Tensile Stress (UTS) values on the same input form. • Frequency domain SOLutions 108 and 111 do not use the Material (CODE) option. This should

be set to None. The CODE and any non-applicable properties will be ignored if set to anything else. Only those properties shown under the None option for Material (CODE) are applicable for frequency domain SOLutions. • Time domain SOLutions 101/103/112 use S-N and ε-N curves defined with Standard

Parameters as stress or strain Range only. Frequency domain SOLs 108/111 can define the S-N or e-N curves using Standard Parameters as Range or Amplitude.

Main Index

Chapter 2: Building A Model 95 Material Library

Cohesive The Input Properties form displays the following for viscoelastic models. This material model is only used in SOL 400 runs and all data is placed on the MCOHE entry. This material is used with interface elements only (PCOHE/CIFQUAD/CIFQDX/CIFHEX/CIFPENT). There are three standard models available, which are discussed below. The strain measures of the interface elements are the relative displacements between the top and the bottom edges (2D) or faces (3D). In 2D, there are two strain components: one normal and one shear. In 3D, there are three components: one normal and two shear. The relative displacements are combined in an equivalent value and the constitutive behavior of the interface elements is defined in terms of an equivalent traction as a function of the equivalent relative displacement. The area below the tractiondisplacement curve is called the cohesive energy (which is also called the critical energy release rate). The names of the three standard cohesive material models refer to the shape of the traction-displacement curve. They have in common that the initial response is elastic or reversible and upon reaching a critical opening displacement, the response is irreversible, which is manifested by a reducing traction and increasing damage in the interface elements (delamination). The models have thefollowing characteristics: Exponential model: entirely defined by an exponential function; the necessary material properties are the cohesive energy (Gc) and the critical opening displacement (vc). Linear model: both the reversible and the irreversible part of the traction-displacement curve are linear; the necessary material properties are the cohesive energy (Gc), the critical opening displacement (vc) and the maximum opening displacement (vm), beyond which the traction is reduced to zero. Linear-exponential model: the reversible part of the traction-displacement curve is linear, where the irreversible part is described by an exponential function; the necessary material properties are the cohesive energy (Gc), the critical opening displacement (vc) and the exponential decay factor (q). Since the exponential model has only two basic parameters, it does not offer the possibility to shift the critical opening displacement without changing the maximum traction (assuming that the cohesive energy remains constant). The other models do offer this possibility, where the irreversible behavior of the linear-exponential model is based on a continuously differentiable curve. Sometimes cohesive materials are defined by the cohesive energy and the maximum traction (tc), instead of the critical or maximum opening displacement. See the MSC Nastran Quick Reference Manual for the relationships to convert such data. Note that for the linear model one still has to select the critical opening displacement Note that for the linear model one still hs to select the critical opening displacment and for the linearexponential model the decay factor. They can be used to influence the reversible response.

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Models

Description

Bilinear

Constitutive Models for Cohesive Material.

Exponential

User Sub. (UCOHESIVE)

The "User Sub.(UCOHESIVE)" model is applicable for MSC Nastran (SOL400) Preference. If selected, the MATUDS entry for MTYPE - MCOHE and UNAME - ucohes is written. The data is placed on MCOHE entry with MODEL set to -1. This material is shown for selection when setting up the UDS Map (See User Defined Services, 367). If UDS Map exists, the MATUDS entry is written to activate user subroutine ucohes in conjunction with MCOHE.

Stiffness Matrix

Description

Secant

Only Secant is currently valid for MSC Nastran.

Tangent

The contribution to the global system matrix can be based on either a modified tangent or secant matrix. The former will usually result faster convergence, but may cause a non-positive definite matrix if the irreversible part of the traction-displacement curve is reached.

Viscous Energy Dissipation

Description

No or Yes

Since upon the onset of delamination the FE analysis may become instable, one can activate some viscous damping. The idea of this damping model is that an extra viscous traction is added to the regular traction. This viscous traction is a function of the rate of the equivalent displacement, a reference value of the rate of the equivalent displacement, the maximum traction and the viscous energy factor:

Linear-Exponential

Main Index

Chapter 2: Building A Model 97 Material Library

Reference Rate

Description

None

If Viscous Energy Dissipation is "No", then this value is "None".

Auto User Defined

The reference value can be entered by the user, but can also be calculated by the program as the largest relative displacement rate in any interface element as long as the response is reversible.

Fully Damages Elements

Description

Keep

This is currently not applicable for MSC Nastran. If an interface element is fully damaged, so if all the integration points have reached the maximum damage, one can deactivate this element. In a contact analysis, this implies that the outer boundary of a contact body is newly determined. The user can decide to either leave deactivated interface elements on the post file or to exclude them from the post file.

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Main Index

Input Parameters

Description

Cohesive Energy

This can also refer a Temperature/Strain/Strain-Rate field.

Critical Opening Displacement

Enter a opening displacmenet values

Maximum Opening Displacement

Used for "Bilinear" model only

Shear-Normal Stress Ratio

The ratio of the maximum stress in shear and the maximum stress in tension

Compression Stiffening Factor

Stiffening factor in compression

Viscous Energy Dissipation

Factor for viscous energy dissipation. This is activated only if, Viscous Energy Dissipation option is set to "Yes".

Reference Rate

Reference rate of relative displacement. This is used if Viscous Energy Dissipation option is set to "Yes" and Reference Rate option is set to "User Defined"

Exponential Decay Factor

Used for Linear-Exponential model only

Thermal Conductance

This can also refer a Temperature/Strain/Strain-Rate field. Used for thermal/coupled analysis only.

Chapter 2: Building A Model 99 Material Library

Composite The Composite forms provide alternate ways of defining the linear elastic properties of materials. All the composite options, except for Laminated Composite, will always result in a homogeneous elastic material in MSC Nastran. When the Laminated Composite option is used to create a material and this material is then referenced in a “Revised or Standard Laminate Plate” element property region, a PCOMP entry is created. However, if this material is referenced by a different type of element property region, for example, “Revised or Standard Homogeneous Plate,” then the equivalent homogeneous material properties are used instead of the laminate lay-up data. Only materials created through the Laminated Composite option should be referenced by a “Revised or Standard Laminate Plate” element property region. Refer to Composite Materials Construction (p. 118) in the Patran Reference Manual. Laminated

This subordinate form appears when the Input Properties button is selected on the Materials form, Composite is the selected Object, and Laminate is the selected Method. Use this form to define the laminate lay-up data for a composite material. If the resulting material is referenced in a “Revised or Standard Laminate Plate” element property region, then an MSC Nastran PCOMP entry containing the lay-up data is written. If the resulting material is referenced by any other type of element property region, the equivalent homogeneous properties of the material are used The difference between the "Total" option and the "Total - %thicknesses" option is that the former requires that the user give actual thickness values of each ply and the latter requires each ply thickness

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to be given as a percentage of the total layup thickness. This is the prefered method when applying the composite material to solid (CHEXA) elements or 2D solid element (axisymmetric, plane strain).

.

Main Index

Chapter 2: Building A Model 101 Element Properties

2.7

Element Properties The Element Properties form appears when the Element Properties toggle, located on the Patran main form, is chosen.There are several option menus available when creating element properties. The selections made on the Element Properties menu will determine which element property form appears, and ultimately, which MSC Nastran element will be created. The following pages give an introduction to the Element Properties form, and details of all the element property definitions supported by the Patran MSC Nastran Preference.

Element Properties Form This form appears when Element Properties is selected on the main menu. There are four option menus on this form. Each will determine which MSC Nastran element type will be created and which property forms will appear. The individual property forms are documented later in this section. For a full description of this form, see Element Properties Forms (p. 69) in the Patran Reference Manual.

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Main Index

Chapter 2: Building A Model 103 Element Properties

Entry Object

Description Use this option menu to define the element’s dimension. The options are: 0D (point elements) 1D (bar elements) 2D (tri and quad elements) 3D (tet, wedge, and hex elements)

Type

This option menu depends on the selection made in the Dimension option menu. Use this menu to define the general type of element, such as: Mass versus Grounded Spring Shell versus 2D_Solid

Expand Property Select

This button is used to quickly edit an element property; for example change the shell thickness.

Options

These option menus may or may not be present, and their contents depend heavily on the selections made in Dimension and Type. See Table 1: for more help.

Input Properties...

This is used to specify element properties; for example shell thickness, or material orientation.

Select Application Region... This is used to specify the region (area) of geometry or elements that are to be included in the property definition. The following table outlines the option menus when Analysis Type is set to Structural.

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Table 1: Structural Element Property Options Dimension 0D

Type • Mass

Option 1 • Coupled page 108 • Grounded page 109 • Lumped page 110

• Grounded Spring page 111 • Grounded Damper page 112 • Grounded Bush

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• Grounded page 113

Option 2

Option 3

Chapter 2: Building A Model 105 Element Properties

Table 1: Structural Element Property Options Dimension 1D

Type • Beam

Option 1 • General Section

Option 2

Option 3

• Standard page 114 • P-Formulation page 120 • Linear/Cubic Closed Section page 122 • Linear-Shear page 123

• Curved w/General Section page 124 • Curved w/Pipe Section page 126 • Lumped Section page 128 • Tapered Section

• Standard page 130 • P-element page 132

• General Section

• Standard page 133 • Linear/Cubic Closed Section page 135 • Linear/Cubic Open Section page 136 • Linear-Shear page 137

• Rod

• General Section

• Standard page 138 • CONROD page 139

• Pipe Section page 140 • Spring page 141 • Damper

• Scalar page 142 • Viscous page 143

• Gap

• Adaptive page 144 • Non-Adaptive page 144

1D Mass page 146 PLOTEL page 147 Bush

• Scalar page 148 • 2D Linear/Non Linear page 150

Spot Weld Connector page 152 Fastener Connector page 153

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Table 1: Structural Element Property Options Dimension 2D

Type • Shell

Option 1 • Thin

Option 2 • Homogeneous

Option 3 • Standard page 156 • Revised page 159 • P-element page 161 • Linear Discrete Kirchhoff page 163

• Laminate

• Standard page 165 • Revised page 167

• Equivalent Section

• Standard page 169 • Revised page 171 • P-element page 173

• Thick

• Standard page 175 • Reduced Integration page 177

• Field Point Mesh page 179 • Bending Panel

• Standard page 180 • Revised page 182 • P-element page 184

• 2D-Solid

• Plane Strain

• Standard page 186 • Reduced page 188 • Revised page 189 • P-Formulation page 190 • Hyperelastic page 192 • Laminated Composite page 193 • Incompressible page 194 • Interface page 195

• Plane Stress

• Standard page 196 • Reduced page 198 • Interface page 199

Main Index

Chapter 2: Building A Model 107 Element Properties

Table 1: Structural Element Property Options Dimension 2D

Type • 2D-Solid

Option 1 • Axisymmetric

Option 2

Option 3

• Standard page 200 • Reduced page 202 • Twist page 203 • Hyperelastic page 204 • Laminated Composite page 205 • PLPLANE page 206 • Incompressible page 207 • Interface page 208

• Acoustic Infinite page 209 • Membrane

• Standard page 210 • Revised page 212 • P-Formulation page 213

• Shear Panel

3D

• Solid

• Homogeneous

• Standard page 217 • Reduced page 219 • P-Formulation page 220 • Hyperelastic page 222 • Solid Shell page 223 • Incompressible page 224

• Laminate page 225 • Gasket • Interface page 226 • Body Pair

• Geometric page 227 • Physical page 229

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0D Element Properties 0D - Coupled Point Mass (CONM1) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

0D

Mass

Coupled

Point/1

Use this form to create a CONM1 element. This defines a 6 x 6 symmetric mass matrix at a geometric point of the structural model. This is a list of Input Properties available for creating a CONM1 element that were not shown on the previous page. Use the menu scroll bar on the Input Properties form to view these properties. Prop Name

Main Index

Description

Mass Orientation CID/CG

Defines the orientation of the 1-2-3 axes of the mass matrix. The value is a reference to an existing coordinate frame. The 1-2-3 axes will be aligned with the X-Y-Z axes of the specified coordinate system. If a non rectangular coordinate system is specified, the system will be evaluated into a local rectangular system, which is then used to orient the mass matrix. This property is the CID field on the CONM1 entry. This property is optional.

Mass Component i,j

Defines the values of the mass matrix. These are the Mij fields on the CONM1 entry. These properties can either be real values or references to existing field definitions. Each of these properties are optional; however, at least one must be defined.

Chapter 2: Building A Model 109 Element Properties

0D - Grounded Scalar Mass (CMASS1) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

0D

Mass

Grounded

Point/1

Use this form to create a CMASS1 element and a PMASS property. This defines a scalar mass element of the structural model. Only one node is used in this method, and the other node is defined to be grounded. Prop Name

Main Index

Description

Mass

Defines the translation mass or rotational inertia value to be applied. This is the M field on the PMASS entry. This property can be either a real value or a reference to an existing field definition. This property is required.

Dof at Node 1

Defines which degree of freedom this value will be attached to. This property can be set to UX, UY, UZ, RX, RY, or RZ and defines the setting for the C1 field on the CMASS1 entry. This property is required.

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0D - Lumped Point Mass (CONM2) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

0D

Mass

Lumped

Point/1

Use this form to create a CONM2 element. This defines a concentrated mass at a geometric point of the structural model. Prop Name

Main Index

Description

Mass

Defines the translational mass value to be used. This is the M field on the CONM2 entry. This property can either be a real value or a reference to an existing field definition. This property is required.

Mass Orientation CID/GG

Defines the orientation of the 1-2-3 axes of the mass matrix. This is a reference to an existing coordinate frame. The 1-2-3 axes will be aligned with the X-Y-Z axes of the specified coordinate system. If a nonrectangular coordinate system is specified, the system will be evaluated into a local rectangular system, which is then used to orient the mass matrix. This is the CID field on the CONM2 entry. If the Value Type is set to Vector then the components of the vector define the center of gravity of the mass in the basic coordinate system and the field for CID is translated as -1. This property is optional.

Mass Offset

Defines an offset from the specified node to where the lumped mass actually is to exist in the structural mode. This vector is defined in the Mass Orientation coordinate system. Defines the X1, X2, and X3 fields on the CONM2 entry. This property is optional.

Inertia i,j

Inertia i,j defines the rotation inertia properties of this lumped mass. These properties are the Iij fields on the CONM2 record. These values can be either real values or references to existing field definitions. These values are optional.

Chapter 2: Building A Model 111 Element Properties

0D - Grounded Scalar Spring (CELAS1/CELAS1D) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Create Modify

0D

Grounded Spring

Option(s)

Topologies Point/1

Use this form to create a CELAS1 or CELAS1D (for SOL 700) element and a PELAS property. This defines a scalar spring element of the structural model. Only one node is used in this method. The other node is defined to be grounded. Prop Name

Main Index

Description

Spring Constant

Defines the coefficient to be used for this spring. This is the K field on the PELAS entry. This can either be a real value or a reference to an existing field definition. This property is required.

Damping Coefficient

Defines what damping is to be included. This is the GE field on the PELAS entry. This property can either be a real value or a reference to an existing field definition. This property is optional.

Stress Coefficient

Defines the relationship between the spring deflection and the stresses within the spring. This property is the S field on the PELAS entry and can either be a real value, or a reference to an existing field definition. This property is optional.

Dof at Node 1

Defines which degree of freedom this value is to be attached to. This can be set to UX, UY, UZ, RX, RY, or RZ. This property defines the setting of the C1 field on the CELAS1 entry. This property is required.

User Def CS Number

Number of a User Defined Coordinate system, used only for Explicit Nonlinear (SOL 700). This property is optional.

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0D - Grounded Scalar Damper (CDAMP1/CDAMP1D) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Create Modify

0D

Grounded Damper

Option(s)

Topologies Point/1

Use this form to create a CDAMP1 or CDAMP1D (for SOL 700) element and a PDAMP property. This defines a scalar damper element of the structural model. Only one node is used in this method. The other node is defined to be grounded. Prop Name

Main Index

Description

Damping Coefficient

Defines the force per unit velocity value to be used. This property is the B field on the PDAMP entry and can either be a real value or a reference to an existing field definition. This property is optional.

Dof at Node 1

Defines which degree of freedom this value is to be attached to. This property can be set to UX, UY, UZ, RY, or RZ and defines the setting for the C1 field on the CDAMP1 entry. This property is required.

User Def CS Number

Number of a User Defined Coordinate system, used only for Explicit Nonlinear (SOL 700). This property is optional.

Chapter 2: Building A Model 113 Element Properties

0D - Grounded Bush (CBUSH/PBUSH) This describes the Input Properties available from the Element Properties form and the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

1D

Bush

Grounded

Bar/2

This is a list of Input Properties available. Use the menu scroll bar on the Input Properties form to view all of these properties. This creates CBUSH/PBUSH entries. Prop Name

Main Index

Description

Bush Orientation System

CID specifies the Grounded Bush Orientation System. The element X,Y, and Z axes are aligned with the coordinate system principal axes. If the CID is for a cylindrical or spherical coordinate system, the grid point specified locates the system. If CID = 0, the basic coordinate system is used.

Spring Constant i Stiff. Freq Depend i

Defines the stiffness associated with a particular degree of freedom. This property is defined in terms of force per unit displacement and can be either a real value or a reference to an existing field definition for defining stiffness vs. frequency.

Stiff. Force/Disp i

Defines the nonlinear force/displacement curves for each degree of freedom of the spring-damper system.

Damping Coefficient i Damp. Freq Depend i

Defines the force per velocity damping value for each degree of freedom. This property can be either a real value or a reference to an existing field definition for defining damping vs. frequency

Structural Damping Struc. Damp Freq Depend

Defines the non-dimensional structural damping coefficient (GE1). This property can be either a real value, or a reference to an existing field definition for defining damping vs. frequency.

Stress Recovery Translation Stress Recovery Rotation

Stress recovery coefficients. The element stress are computed by multiplying the stress coefficients with the recovered element forces.

Strain Recovery Translation Strain Recovery Rotation

Strain Recovery Coefficients. The element strains are computed by multiplying the strain coefficients with the recovered element strains.

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1D Element Properties 1D - Beam - General Section (CBAR) - Standard Formulation This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section

Standard Formulation

Bar 2

Use this form to create CBAR elements with a PBAR or PBARL property. A CBARAO entry will be generated if any Station Distances are specified. This defines a simple beam element in the structural model. If used in a SOL 400 run, a PBARN1 entry may also be written with the LC option written to the BEHi field. Note:

.Patran will check the element associativity to other elements sharing this property set and will not export user defined pin unless the user includes an asterisk (*) in the string, in which case Patran will export the defined pin flags for all elements in the property set.

Most of the beam properties that appear on all beam/bar input property forms are listed here. Only those applicable to the element type being created will appear on the input properties form. Prop Name Section Name

Description Specifies a beam section previously created using the beam library Allows you to define a bar/beam section either by Dimensions (PBARL/PBEAML) or by Properties (PBAR/PBEAM). If Dimensions is choosen, the MSC Nastran’s built-in section library (Version 69 and later), PBARL/PBEAML, (for the standard Beam Library) or PBRSECT/PBMSECT (for an Arbitrary section) will be used to define the bar/beam. If Properties is chosen, the standard bar/beam properties, PBAR/PBEAM will be used to define the beam section. If the Dimensions Option is set to Dimensions, the Translation Parameters Version must be set to version 69 or later.

Material Name

Main Index

Defines the material to be used. A list of all materials currently in the database is displayed when data is entered. Either select from the list using the mouse, or type in the name. This property defines the value to be used in the MID field on the PBAR/PBEAM entry. This property is required.

Chapter 2: Building A Model 115 Element Properties

Prop Name Bar Orientation

Description Defines the local element coordinate system to be used for any cross-sectional properties. This orientation will define the local XY plane, where the x-axis is along the beam. This orientation defines the value for the X1, X2, X3, or G0 fields on the CBAR/CBEAM entry. This property is required. Specifies how the bar orientation is defined: Vector – Specified using a vector Node Id – Specified using an existing node in the beam XY plane When the value type is Vector, it is always input in either the Patran global or some other Patran user defined coordinate system (i.e. ).

Reference Coordinates

Specifies the MSC Nastran coordinate system in which the bar/beam orientation vector will be written to the CBAR/CBEAM entry: Analysis - Displacement Coordinate System at GA Coord 0 - Basic Coordinate System If Analysis is specified, a G will be written to the first position of the OFFT value on the CBAR/CBEAM entry. If Coord 0 is specified, a B will be written. Note: The reference coordinate system specified does not affect how the input is interpreted within Patran. Only how it is written to the CBAR/CBEAM entry.

Offset @ Node 1 Offset @ Node 2

Defines the offset from the nodes to the actual centroids of the beam cross section. These orientations are defined as vectors. These properties, after any necessary transformations, become the W1A, W2A, W3A, W1B, W2B, and W3B fields on the CBAR/CBEAM entry. These properties are optional. Vector – Specified using a vector This is the only method available. The Reference Coordinate System controls how the vector input is interpreted in Patran.

Main Index

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Patran Interface to MSC Nastran Preference Guide Element Properties

Prop Name Reference Coordinates

Description Specifies the MSC Nastran coordinate system in which the offset vectors will be written to the CBAR/CBEAM entry and how the vector input will be interpreted in Patran: Analysis - Displacement Coordinate Systems at GA and GB Element - Element Coordinate System If Analysis is specified, a G will be written to the second or third position of the OFFT value on the CBAR entry. Within Patran, the vector will be interpreted to be in either the Patran global or some other Patran user defined coordinate system (i.e. ). If Element is specified, an E will be written to the second or third position of the OFFT value on the CBAR entry. Within Patran, the vector will be interpreted to be in the Element coordinate system.

Pinned DOFs @ Node 1 Pinned DOFs @ Node 2

These degrees of freedom are in the element local coordinate system. Values that can be specified are UX, UY, UZ, RX, RY, RZ, or any combination. These properties are used to remove connections between the node and selected degrees of freedom at the two ends of the beam. This option is commonly used to create a pin connection by specifying RX, RY, and RZ to be released. Defines the setting of the PA and PB fields on the CBAR/CBEAM record. These properties are optional. Note that if pinned DOF releases are defined within a property set, but the end nodes of the beams are connected to beams of a different property set, then no pinned DOFs will be written for those beams (PA or PB will be left blank). To override this and force the pin flags to be written per the property set, use an "*" after the specification for the DOFs. (This may be problematic if the property sets defined different pin DOFs.) For example, if rotation about the 2nd DOF is to be freed, specify "RY*." These values must be typed into the data box. Although there is a pull down menu next to the data box showing the valid selections, you will have to type the values in if more than one DOF or the "*" is to be specified. Specifying the "*" by itself does nothing.

Area

Main Index

Defines the cross-sectional area of the element. This is the A field on the PBAR/PBEAM entry. This value can be either real values or a reference to an existing field definition. This property is required.

Chapter 2: Building A Model 117 Element Properties

Prop Name

Main Index

Description

Inertia i,j

Defines the various area moments of inertia of the cross section. These are the I1, I2, and I12 fields on the PBAR/PBEAM entry. These values can be either real values or references to existing field definitions. These values are optional.

Torsional Constant

Defines the torsional stiffness of the beam. This is the J field on the PBAR/PBEAM entry. This value can be either a real value or a reference to an existing field definition. This property is optional.

Shear Stiff, Y Shear Stiff, Z

Defines the shear stiffness values. These are the K1 and K2 fields on the PBAR/PBEAM entry. These values can be either real value or references to existing field definitions. This property is optional.

Shear Relief Y Shear Relief Z

Defines the shear relief coefficients due to taper. These are the S1 and S2 fields on the PBEAM entry. These values can either be real values or references to existing field definitions. These properties are optional.

Nonstructural Mass

Defines mass not included in the mass derived from the material of the element. This is defined in terms of mass per unit length of the beam. This is the NSM field on the PBAR/PBEAM entry. This value can be either a real value or reference to an existing field definition. This property is optional.

NSM Inertia @ Node 1 NSM Inertia @ Node 2

Specified the nonstructural mass moments of inertia per unit length about the nonstructural mass center of gravity at each end of the element. These properties are the NSI(A) and NSI(B) fields on the PBEAM entry. These values can be either real values or references to existing field definitions. These properties are optional.

Y of NSM @ Node 1 Z of NSM @ Node 1 Y of NSM @ Node 2 Z of NSM @ Node 2

Defines the offset from the centroid of the cross section to the location of the nonstructural mass. These values are measured in the beam cross-section coordinate system. These are the M1(A), M2(A), M1(B), and M2(B) fields on the PBEAM entry. These values can be either real values or references to existing field definitions. These properties are optional.

Y of Point C Z of Point C Y of Point D Z of Point D Y of Point E Z of Point E Y of Point F Z of Point F

Indicates the stress recovery. They define the Y and Z coordinates of the stress recovery points across the section of the beam, as defined in the local element coordinate system. These are the C1, C2, D1, D2, E1, E2, F1, and F2 fields on the PBAR entry. These values can be either real values or references to existing field definitions. These properties are optional.

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Patran Interface to MSC Nastran Preference Guide Element Properties

Prop Name

Main Index

Description

Y of NA @ Node 1 Z of NA @ Node 1 Y of NA @ Node 2 Z of NA @ Node 2

Defines the offset from the shear center of the cross section to the location of the neutral axis. These values are measured in the beam cross-section coordinate system. These are the N1(A), N2(A), N1(B), and N2(B) fields on the PBEAM entry. These values can be either real values or references to existing field definitions. These properties are optional.

[Contact Beam Radius]

This allows the equivalent radius for beam-to-beam contact to be different for each beam cross section. The MSC Nastran entry BCBMRAD is written to the .bdf file. The BCBMRAD entry format is different for SOL 400 and SOL 600. You must turn on beam-to-beam contact under the Analysis application (contact parameters / contact detection) for this parameter to be written.

Section Integration

Used only for Sol 400. Value is written to the SECT field of the PBARN1/PBEMN1 entry.

Nonlinear Formulation

This optional property word can take on any of the three values Automatic, Large Strain, or Small Strain and is only recognized for implicit nonlinear (SOL 400) analyses. Automatic is the default if not specified and determines if large or small strain is appropriate based on the existence of an elastoplastic material constitutive model and/or if the elements are contained in a contact body. If appropriate, the PBARN1/PBEMN1 entry is written for this property set. Large Strain forces the PBARN1/PBEMN1 entry to be written, regardless; and Small Strain forces it not to be written, regardless. In addition, if large strain is forced or detected, the usage of NLMOPTS, LRGSTRN,0 or 1 is written based on the setting on the Load Increment Parameters form when defining a Subcase. See Static Subcase Parameters for Implicit Nonlinear Solution Type, 436.

Chapter 2: Building A Model 119 Element Properties

Prop Name

Main Index

Description

Create Sections I C L ..., Beam Library

Activates the Beam Library forms. These forms will allow the user to define beam properties by choosing a standard cross section type and inputing dimensions.

Weld Nugget Diameter Top/Bot Sheet Thickness

These optional properties are used for defining spot weld parameters (weld diameter and connecting sheet thicknesses) in an MSC Nastran Embedded Fatigue analyses of spot welds for time domain solutions using statics (SOL 101), normal modes (SOL 103), or modal transient response (SOL 112). All parameters defined here are placed on the PFTG bulk data entry. For the sheet thickness, enter two values separated by spaces. If only one is provided both top and bottom thickness retain the same value for both. If not defined, the thicknesses are determined from the connecting sheet properties. If the diameter is left blank, a diameter is determined through a look up table based on the minimum thickness of the connecting sheets.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Beam - General Section (CBEAM) - P-Formulation This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section

P-Formulation

Bar 2/3/4

Use this form to create CBEAM elements with a PBEAM or PBEAML property along with the Pformulation entries ADAPT and PVAL. This form defines a simple beam element in the structural model for an adaptive, p-element analysis. Note:

.Patran will check the element associativity to other elements sharing this property set and will not export user defined pin unless the user includes an asterisk (*) in the string, in which case Patran will export the defined pin flags for all elements in the property set.

Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 114 for the generic properties needed for any beam/bar definition. Additional properties for P-formulation are listed here. Prop Name Starting P-orders and Maximum P-orders

Main Index

Description Polynomial orders for displacement representation within elements. Each contains a list of three integers referring to the directions defined by the P--order Coordinate System (default elemental). Starting P-orders apply to the first adaptive cycle. The adaptive analysis process will limit the polynomial orders to the values specified in Maximum P-orders. These are the Polyi fields on the PVAL entry.

P-order Coord. System

The three sets of three integer p-orders above refer to the axes of this coordinate system. By default, this system is elemental. This is the CID field on the PVAL entry.

Activate Error Estimate

Flag that controls whether or not this set of elements participates in the error analysis. This is the ERREST field on the ADAPT entry.

P-order Adaptivity

Controls the particular type of p-order adjustment from adaptive cycle to cycle. This is the TYPE field on the ADAPT entry.

Error Tolerance

The tolerance used to determine if the adaptive analysis is complete. By default this value is equal to 0.1. This is the ERRTOL field on the ADAPT entry.

Chapter 2: Building A Model 121 Element Properties

Prop Name

Main Index

Description

Stress Threshold Value

Elements with von Mises stress below this value will not participate in the error analysis. By default this value is equal to 0.0. This is the SIGTOL field on the ADAPT entry.

Strain Threshold Value

Elements with von Mises strain below this value will not participate in the error analysis.By default this value is equal to1.0E-8. This is the EPSTOL field on the ADAPT entry.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Beam - General Section (CBAR) - Linear/Cubic Closed Section This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section

Linear/Cubic Closed Section

Bar 2

Use this form to create CBAR elements with a PBAR or PBARL property and associated PBARN1 to define nonlinear, large displacement, large strain behavior for use in SOL 400. A PBARN1 entry is written with LCC option written to the BEHi field. A CBARAO entry will be generated if any Station Distances are specified. This defines a simple beam element in the structural model. Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 114 for the generic properties needed for any beam/bar definition. Properties specific to defining this beam behavior are listed here. Prop Name Section Integration

Main Index

Description Used only for Sol 400. Value is written to the SECT field of the PBARN1/PBEMN1 entry. Asmeared cross section or a numerically integrated cross section can be defined.

Chapter 2: Building A Model 123 Element Properties

1D - Beam - General Section (CBAR) - Linear-Shear This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section

Linear-Shear

Bar 2

Use this form to create CBAR elements with a PBAR or PBARL property and associated PBARN1 to define nonlinear, large displacement, large strain behavior for use in SOL 400. A PBARN1 entry is written with LS option written to the BEHi field. A CBARAO entry will be generated if any Station Distances are specified. This defines a simple beam element in the structural model. Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 114 for the generic properties needed for any beam/bar definition. Properties specific to defining this beam behavior are listed here. Prop Name Section Integration

Main Index

Description Used only for Sol 400. Value is written to the SECT field of the PBARN1/PBEMN1 entry. Asmeared cross section or a numerically integrated cross section can be defined.

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1D - Beam - Curved with General Section (CBEND) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

1D

Beam

Curved w/General Section

Bar 2

Use this form to create CBEND elements with a PBEND property. This form defines a curved beam element of the structural model. The CBEND element has several ways to define the radius of the bend and the orientation of that curvature.This element always uses the method of defining the center of curvature point (GEOM=1). An alternate property of the Curved Pipe element also exists. Properties specific to defining this beam behavior are listed here. Prop Name

Main Index

Description

Material Name

Defines the material to be used. A list of all materials currently in the database is displayed when data is entered. Either select from the list using the mouse, or type in the name. This property defines the setting of the MID field on the PBEND entry. This property is required.

Center of Curvature Vector

Defines the center of curvature of the pipe bend. It is done by either specifying a vector from the first node of the element or by referencing a node. The CBEND element in MSC Nastran has several ways to define the radius of the pipe bend and the orientation of that curvature. This defines the settings of the X1, X2, X3, and G0 fields of the CBEND entry. This property is required.

Radial Bar Offset Axial Bar Offset

Defines the offset from the nodes to the actual centroids of the beam cross section. These properties define the settings of the RC and ZC fields on the PBEND entry. These values can either be real values or references to existing field definitions. This property is optional.

Area

Defines the cross-sectional area of the element. This property is the A field on the PBEND entry. This value can be either a real value or a reference to an existing field definition. This property is optional.

Inertia 1,1 Inertia 2,2

Defines the various area moments of inertia of the cross section. These properties are the I1 and I2 fields on the PBEND entry. These values can either be real values or references to existing field definitions. These values are optional.

Torsional Constant

Defines the torsional stiffness of the beam. This is the J field on the PBEND entry. This value can be either a real value, or a reference to an existing field definition. This property is optional.

Chapter 2: Building A Model 125 Element Properties

Prop Name

Main Index

Description

Shear Stiff, R Shear Stiff, Z

Defines the shear stiffness values. These properties are the K1 and K2 fields on the PBEND entry. These values can be either real values or references to existing field definitions. This property is optional.

Nonstructural Mass

Defines mass not included in the mass derived from the material of the element. This property is defined in terms of mass per unit length of the beam and is the NSM field on the PBEND entry. This value can be either real value or a reference to an existing field definition. This property is optional.

Radial NA Offset

Defines the radial offset of the geometric centroid from the end nodes. Positive values move the centroid of the section towards the center of curvature of the pipe bend. This property is the DELTAN field on the PBEND entry. This value can be either a real value or a reference to an existing field definition. This property is optional.

R of Point C Z of Point C R of Point D Z of Point D R of Point E Z of Point E R of Point F Z of Point F

These properties are for stress recovery. They define the R and Z coordinates of the stress recovery points across the section of the beam, as defined in the local element coordinate system. These properties are the C1, C2, D1, D2, E1, E2, F1 and F2 fields on the PBEND entry. These values can be either real values or references to existing field definitions. These properties are optional.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Beam - Curved with Pipe Section (CBEND) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create

1D

Beam

Curved W/Pipe Section

Bar 2

Use this form to create CBEND elements with a PBEND property. This defines a curved pipe or elbow element of the structural model. The internal pressure is defined as part of the element definition because, for pipe elbows, the internal pressure affects the element stiffness. Properties specific to defining this beam behavior are listed here. Prop Name

Main Index

Description

Material Name

Defines the material to be used. A list of all materials currently in the database is displayed when data is entered. Either select from the list using the mouse, or type in the name. Defines the MID field on the PBEND entry. This property is required.

Center of Curvature Vector

Defines the center of curvature of the pipe bend. This can be done either by specifying a vector from the first node of the element or by referencing a node. The CBEND element in MSC Nastran has several ways to define the radius of the pipe bend and the orientation of that curvature. Defines the settings of the X1, X2, X3, and G0 fields on the CBEND entry. This element in Patran always uses the method of defining the center of curvature point (GEOM=1). This value is required.

Radial Bar Offset Axial Bar Offset

Defines the offset from the nodes to the actual centroids of the pipe cross section. These are the RC and ZC fields on the PBEND entry. These values can either be real values or references to existing field definitions. These properties are optional.

Mean Pipe Radius

Indicates the distance from the centroid of the pipe cross section to mid-wall location. This is the r field on the PBEND entry. This value can either be a real value or a reference to an existing field definition. This property is required.

Pipe Thickness

Indicates the wall thickness of the pipe. This is the t field on the PBEND entry. This value can be either a real value or a reference to an existing field definition. This property is required.

Internal Pipe Pressure

Indicates the static pressure inside the pipe elbow. This is the P field on the PBEND entry. This value can be either a real value or a reference to an existing field definition. This property is optional.

Chapter 2: Building A Model 127 Element Properties

Prop Name

Main Index

Description

Nonstructural Mass

Defines mass not included in the mass derived from the material of the element. This property is defined in terms of mass per unit length of the beam and is the NSM field on the PBEND entry. This value can either be a real value or a reference to an existing field definition. This property is optional.

Stress Intensification

Indicates the desired type of stress intensification to be used. This is a character string value. This property is the FSI field on the PBEND entry. Valid settings of this parameter are General, ASME, and Welding Council.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Beam - Lumped Section (CBEAM/PBCOMP) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create

1D

Beam

Lumped Section

Bar 2

Use this form to create CBEAM elements with a PBCOMP property. This defines a beam element of constant cross section, using a lumped area element formulation.The orientation vector can be defined as either a vector or a reference to an existing node in the XY plane. Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 114 for the generic properties needed for any beam/bar definition. Properties specific to defining this beam behavior are listed here. Prop Name

Main Index

Description

Material Name

Defines the material to be used. A list of all materials currently in the database is displayed when data is entered. Either select from the list using the mouse, or type in the name. This defines the setting of the MID field on the PBCOMP entry. This property is required.

Area

Defines the cross-sectional area of the element. This is the A field on the PBCOMP entry. This value can be either a real value or a reference to an existing field definition. This property is optional.

Nonstructural Mass

Defines mass not included in the mass derived from the material of the element. This is defined in terms of mass per unit length of the beam. This is the NSM field on the PBCOMP record. This value can be either a real value or a reference to an existing field definition. This property is optional.

Shear Stiff, Y Shear Stiff, Z

Defines the shear stiffness values. These are the K1 and K2 fields on the PBCOMP entry. This value can be either a real value or a reference to an existing field definition. This property is optional.

Y of NSM Z of NSM

Defines the offset from the centroid of the cross section to the location of the nonstructural mass. These values are measured in the beam cross-section coordinate system. These properties are the M1 and M2 fields on the PBCOMP entry. These values can be either real values or references to existing field definitions. These properties are optional.

Chapter 2: Building A Model 129 Element Properties

Prop Name

Main Index

Description

Symmetry Option

Specifies which type of symmetry is being used to define the lumped areas of the beam cross section. This is a character string parameter. The valid settings are No Symmetry, YZ Symmetry, Y Symmetry, Z Symmetry, or Y=Z Symmetry. This defines the setting of the SECTION field on the PBCOMP entry. This property is optional.

Ys of Lumped Areas Zs of Lumped Areas

Defines the locations of the various lumped areas. These are defined in the cross-sectional coordinate system. These properties define the Yi and Zi fields on the PBCOMP entry. These values are lists of real values. These properties are optional.

Area Factors

Defines the Fraction of the total area to be included in this lumped area. The sum of all area factors for a given section must equal 1.0. If the data provided does not meet this requirement, the values will all be scaled to the corrected value. These properties define the values for the Ci fields on the PBCOMP entry. These values are lists of real values. These properties are optional.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Beam - Tapered Section (CBEAM) - Standard Formulation This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

Tapered Section

Standard Formulation

Bar 2

Use this form to create CBEAM elements with a PBEAM or PBEAML property. This defines a beam element with varying cross sections. The difference between defining a tapered section and a constant section is the ability to define station locations along the beam and various values at those stations as a real list. Real lists are entered by separating values in the databoxes by spaces or commas. There should be the same number of values in each data box corresponding to the number of stations. If less values are entered than the number of stations, the missing values will take on the last value entered. A general section beam can also be used to define a tapered section beam. See 1D - Beam - General Section (CBEAM) - Standard Formulation, 133. Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 114 for the generic properties needed for any beam/bar definition. Properties specific to defining this beam behavior are listed here. Prop Name

Main Index

Description

Station Distances

Defines stations along each beam element where the section properties will be defined. The values specified here are fractions of the beam length. These values, therefore, are in the range of 0. to 1. These values define the settings of the X/XB fields on the PBEAM record. These values are real values. These properties are optional. Enter them as a list each value being separated by a space.

Cross-Sect. Areas

Defines the cross-sectional area of the element. This property defines the settings of the A fields on the PBEAM record. This value can be either a real value, or reference to an existing field definition or entered as a list. This property is required.

Inertias i,j

Defines the various area moments of inertia of the cross section. These defines the settings of the I1, I2, and I12 fields on the PBEAM entry. These values are real values entered as a list. These properties are optional.

Torsional Constants

Defines the torsional stiffness parameters. This property defines the J fields on the PBEAM entry. This is a list of real values, one for each station location. This property is optional.

Chapter 2: Building A Model 131 Element Properties

Prop Name

Main Index

Description

Ys of C Points Zs of C Points Ys of D points Zs of D Points Ys of E Points Zs of E Points Ys of F Points Zs of F Points

Defines the Y and Z locations in element coordinates, relative to the shear center for stress data recovery. These define the C1, C2, D1, D2, E1, E2, F1, and F2 fields on the PBEAM entry. These are lists of real values, one for each station location. These properties are optional.

Nonstructural Masses

Defines the mass not included in the mass derived from the material of the element. This is defined in terms of mass per unit length of the beam. This property is the NSM field on the PBEAM entry. This is a list of real values, one for each station location. This property is optional.

Shear Stiff, Y Shear Stiff, Z

Defines the shear stiffness values. These properties are the K1 and K2 fields on the PBEAM entry. These values can be either real values or references to existing field definitions. These properties are optional.

Shear Relief Y Shear Relief Z

Defines the shear relief coefficients due to taper. These are the S1 and S2 fields on the PBEAM entry. These values can either be real values or references to existing field definitions. These properties are optional.

Warp Coeff. @ Node 1 Warp Coeff. @ Node 2

Specifies the warping coefficient at each end of the element. These properties are the CW(A) and CW(B) fields on the PBEAM entry. These values can be either real values or references to existing field definitions. These properties are optional.

Y of NA @ Node 1 Z of NA @ Node 1 Y of NA @ Node 2 Z of NA @ Node 2

Defines the offset from the centroid of the cross section to the location of the neutral axis. These values are measured in the beam cross section coordinate system and are the N1(A), N2(A), N1(B), and N2(B) fields on the PBEAM entry. These values can be either real values or references to existing field definitions. These properties are optional.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Beam - Tapered Section (CBEAM) - P-Formulation This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

Tapered Section

P- Formulation

Bar 2

Use this form to create CBEAM elements with a PBEAM or PBEAML property along with the Pformulation entries ADAPT and PVAL. This defines a beam element with varying cross sections. The difference between defining a tapered section and a constant section is the ability to define station locations along the beam and various values at those stations as a real list. Real lists are entered by separating values in the databoxes by spaces or commas. There should be the same number of values in each data box corresponding to the number of stations. If less values are entered than the number of stations, the missing values will take on the last value entered. Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 114 for the generic properties needed for any beam/bar definition. Additional properties for P-formulation are listed described in 1D - Beam - General Section (CBEAM) P-Formulation, 120.

Property values that can accept real lists for definig the taper of the beam are described in 1D - Beam Tapered Section (CBEAM) - Standard Formulation, 130.

Main Index

Chapter 2: Building A Model 133 Element Properties

1D - Beam - General Section (CBEAM) - Standard Formulation This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section (CBEAM)

Standard Formulation

Bar 2

Use this form to create CBEAM elements with a PBEAM or PBEAML property. This defines a beam element with varying cross sections. This set of options provides a method of creating beam models with warping due to torsion. The capabilities of this beam properties formulation option are similar to those of the “Tapered Section” formulation, except that warping due to torsion is handled more conveniently. If SOL 400 is used and non-linear formulations set, a PBEMN1 entry is written with BEAM option written to the BEHi field and LC written to the INTi field. Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 114 for the generic properties needed for any beam/bar definition. Also see 1D - Beam Tapered Section (CBEAM) - Standard Formulation, 130 for a description of defining tapered beam properties. Properties specific to defining this beam behavior are listed here. Prop Name Warping Option

Description This specifies how contraints should be applied to the warping SPOINTs of unmatched ends within the application region (see continuity rules above). The choices available include “A free B free”, “A fixed B fixed”, “A free B fixed”, “A fixed B free”, or “None”. The choice of “None” is used to disable warping altogether for the current element property set, in which case no SPOINTs will be generated or constrained. Only unmatched ends within the application region will be eligible for constraining, and whether or not a constraint is applied will depend on the option selected, and whether the unmatched end is “End A” or “End B” of its beam element. If no selection is made for this element property, “A free B free” is selected by default.

Warping due to torsion is enabled by generating MSC Nastran SPOINTs to contain the warping degrees of freedom. These SPOINTs are not actually present in the Patran database, and there is no way to recover any results for these SPOINTs. They are created during analysis deck translation, and provide the means to communicate to MSC Nastran the continuity and constraint properties of the warping degrees of freedom in the model. These attributes of continuity and constraint are implied in the Patran database through the composition of the element properties application region and the set of options selected. These continuity and constraint attributes apply to both warping SPOINTs and end release flags. This connection of these attributes to the composition of the application region is new since Patran 2001r3, and represents a change in behavior from previous versions of Patran. The general rules of implied continuity are as follows.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1. Within the application region, two beam elements are taken to be continuous if a GRID ID at an end of one of the beam elements matches a GRID ID at one of the ends of the other beam element. If a third beam element in the same application region also contains the same GRID ID, it is assumed that none of the beam elements is continuous at this location. This condition is known as a “multiple junction”. Similarly, if none of the other beam elements in the application region contain a matching GRID ID, the corresponding end of the beam element is taken to be not continuous. This condition is known as an “unmatched end”. 2. If warping is enabled, then all instances of beam element continuity must have the matching GRID ID located at “End A” of one of the beam elements and at “End B” of the other. “End A” and “End B” positions are determined by the order of GRID IDs specified in the element connectivity array, and the positive direction of the x-axis of the element coordinate system points from “End A” to “End B”. If warping is not enabled, this restiction does not apply. If warping is enabled, any violation of this requirement will result in a failure to complete the translation of the finite element model. In this event, the user will have to reverse the direction of the improperly oriented beam elements and initiate the translation again. 3. When warping is enabled, all positions of beam element continuity within an application region will be represented by a single SPOINT at each of these positions, which will be generated at the time of analysis deck translation and will appear on the CBEAM entries for the appropriate end of both of the beam elements that are continuous at each location. If any end release codes have been prescribed for the application region, they will not be applied at locations of beam element continuity. This is new for Patran 2001r3. For earlier versions of Patran, end release codes would be applied to all elements of the application region, regardless of continuity. 4. When warping is enabled, individual SPOINTs are generated for all beam ends that are not continuous. This applies to both “multiple junctions” and “unmatched ends”. 5. The specified end release codes are applied to all discontinuous beam element ends in the application region, whether “multiple junction” or “unmatched end”, with the applied end release codes dependent on what has been prescribed for “End A” and “End B” for the application region. If no end release codes have been prescribed for the application region, none are generated. 6. When warping is enabled, and for unmatched ends only (not multiple junctions), constraints applied to the SPOINTs are specified by the “warping option” specified in the element properties form. For example, if “A free B fixed” has been selected and the unmatched end is “End A” of its beam element, it will not be constrained. If it is “End B” of its element, it will be constrained. The warping SPOINT for a beam element end involved in a multiple junction will not be constrained under any circumstances. If the user wishes to constrain warping for a beam element involved in a multiple junction, he will have to do so by splitting the application region in such a way that the beam element end becomes an “unmatched end” within its new application region. 7. Warping is considered to be enabled when a value has been specified for the warping coefficient at either end of the beam element. When the user selects the “Beam Library” option, values for the warping coefficient get computed autamatically, and thus warping is implicitly enabled. If the user wishes to disable warping while using the Beam Library option, he must choose “None” as his “Warping Option” on the “Input Properties ...” form.

Main Index

Chapter 2: Building A Model 135 Element Properties

1D - Beam - General Section (CBEAM) - Linear/Cubic Closed Section This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section (CBEAM)

Linear/Cubic Closed Section

Bar 2

Use this form to create CBEAM elements with a PBEAM or PBEAML property and associated PBEMN1 to define nonlinear, large displacement, large strain behavior for use in SOL 400. A PBEMN1 entry is written with BEAM option written to the BEHi field and LCC written to the INTi field. Please see the description of properties listed in 1D - Beam - General Section (CBEAM) - Standard Formulation, 133 for the generic properties needed for any beam/bar definition. Properties specific to defining this beam behavior are listed here. Prop Name Section Integration

Main Index

Description Used only for Sol 400. Value is written to the SECT field of the PBARN1/PBEMN1 entry. Asmeared cross section or a numerically integrated cross section can be defined.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Beam - General Section (CBEAM) - Linear/Cubic Open Section This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section

Standard Formulation

Bar 2

Use this form to create CBEAM elements with a PBEAM or PBEAML property and associated PBEMN1 to define nonlinear, large displacement, large strain behavior for use in SOL 400. A PBEMN1 entry is written with BEAM option written to the BEHi field and LCO written to the INTi field Please see the description of properties listed in 1D - Beam - General Section (CBEAM) - Standard Formulation, 133 for the generic properties needed for any beam/bar definition. Properties specific to defining this beam behavior are listed here. Prop Name Section Integration

Main Index

Description Used only for Sol 400. Value is written to the SECT field of the PBARN1/PBEMN1 entry. Asmeared cross section or a numerically integrated cross section can be defined.

Chapter 2: Building A Model 137 Element Properties

1D - Beam - General Section (CBEAM) - Linear-Shear This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section

Standard Formulation

Bar 2

Use this form to create CBEAM elements with a PBEAM or PBEAML property and associated PBEMN1 to define nonlinear, large displacement, large strain behavior for use in SOL 400. A PBEMN1 entry is written with BEAM option written to the BEHi field and LS written to the INTi field Please see the description of properties listed in 1D - Beam - General Section (CBEAM) - Standard Formulation, 133 for the generic properties needed for any beam/bar definition. Properties specific to defining this beam behavior are listed here. Prop Name Section Integration

Main Index

Description Used only for Sol 400. Value is written to the SECT field of the PBARN1/PBEMN1 entry. Asmeared cross section or a numerically integrated cross section can be defined.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Rod - General Section (CROD) - Standard Formulation This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Rod

General Section

Standard Formulation

Bar 2

Use this form to create a CROD element and a PROD property. This defines a tension-compressiontorsion element of the structural model. Prop Name

Description

Material Name

Defines the material to be used. A list of all materials currently in the database is displayed when data is entered. Either select from the list using the mouse or type in the name. This defines the setting of the MID field on the PROD entry. This property is required.

Area

Defines the cross-sectional area of the element. This is the A field on the PROD entry. This value can be either a real value or a reference to an existing field definition. This property is required.

Torsional Constant

Defines the torsional stiffness of the beam. This is the J field on the PROD entry. This value can be either a real value or a reference to an existing field definition. This property is optional.

Torsional Stress Coefficient Defines the coefficient to determine the torsional stress. This is the C field on the PROD entry. This property can be either a real value or a reference to an existing field definition. This property is optional.

Main Index

Nonstructural Mass

Defines mass not included in the mass derived from the material of the element. This property is defined in terms of mass per unit length of the beam. This is the NSM field on the PROD entry. This value can be either a real value or a reference to an existing field definition. This property is optional.

Contact Beam Radius

Defines the radius of the beam for beam to beam contact in SOL 600/400.

Chapter 2: Building A Model 139 Element Properties

1D - Rod - General Section - CONROD This describes the Input Properties available from theElement Properties form when the following options are chosen. Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Rod

General Section

CONROD

Bar 2

Use this form to create a CONROD element. This defines a tension-compression-torsion element of the structural model. Prop Name

Description

Material Name

Defines the material to be used. A list of all materials currently in the database is displayed when data is entered. Either select from the list using the mouse, or type in the name. This defines the setting of the MID field on the CONROD entry. This property is required.

Area

Defines the cross-sectional area of the element. This property is the A field on the CONROD entry. This value can be either a real value or a reference to an existing field definition. This property is required.

Torsional Constant

Defines the torsional stiffness of the beam. This property is the J field on the CONROD entry. This value can either be a real value or a reference to an existing field definition. This property is optional.

Torsional Stress Coefficient Defines the coefficient to determine the torsional stress. This property is the C field on the CONROD entry and can either be a real value or a reference to an existing field definition. This property is optional. Nonstructural Mass

Main Index

Defines mass not included in the mass derived from the material of the element. This property is defined in terms of mass per unit length of the beam and is the NSM field on the CONROD entry. This value can be either a real value or a reference to an existing field definition. This property is optional.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Rod - Pipe Section (CTUBE) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

1D

Rod

Pipe Section

Bar 2

Use this form to create a CTUBE element and a PTUBE property. This defines a tension-compressiontorsion element with a thin-walled tube cross section. Prop Name

Main Index

Description

Material Name

Defines the material to be used. A list of all materials currently in the database is displayed when data is entered. This property defines the setting of the MID field on the PTUBE entry. Either select from the list using the mouse, or type in the name. This property is required.

Outer Diameter @ Node 1 Outer Diameter @ Node 2

Defines the tube outer diameters at each end of the element. These are the OD and OD2 fields on the PTUBE entry. These values can either be real values or references to existing field definitions. The outer diameter at Node 1 property is required. The outer diameter at Node 2 Property is optional.

Pipe Thickness

Specifies the wall thickness of the pipe. This is the T field on the PTUBE entry. This value can either be a real value or a reference to an existing field definition. This property is required.

Nonstructural Mass

Defines mass not included in the mass derived from the material of the element. This property is defined in terms of mass per unit length of the beam and is the NSM field on the PTUBE entry. This value can be either a real value or reference to an existing field definition. This property is optional.

Chapter 2: Building A Model 141 Element Properties

1D - Spring (CELAS1) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Create Modify

1D

Spring

Option(s)

Topologies Bar/2

Use this form to create a CELAS1 or CELAS1D (for SOL 700) element and a PELAS property. This defines a scalar spring of the structural model. Prop Name

Main Index

Description

Spring Constant

Defines the coefficient to be used for this spring. This property is the K field on the PELAS entry and can be either a real value or a reference to an existing field definition. This property is required.

Damping Coefficient

Defines what damping is to be included. This property is the GE field on the PELAS entry and can be either a real value or a reference to an existing field definition. This property is optional.

Stress Coefficient

Defines the relationship between the spring deflection and the stresses within the spring. This property is the S field on the PELAS entry and can be either a real value or a reference to an existing field definition. This property is optional.

Dof at Node 1 Dof at Node 2

Defines which degree of freedom this value is to be attached to at each node. The degree of freedom can be set to UX, UY, UZ, RX, RY, or RZ. These properties define the settings of the C1 and C2 fields on the CELAS1 entry. These properties are required.

User Defined Coordinate System Number

Number of a User Defined Coordinate system, used only for Explicit Nonlinear (SOL 700). This property is optional.

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Damper - Scalar (CDAMP1) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

1D

Damper

Scalar

Bar/2

Use this form to create a CDAMP1 or CDAMP1D (for SOL 700) element and a PDAMP property. This defines a scalar damper element of the structural model. Prop Name

Description

Damping Coefficient

Defines the force per unit velocity value to be used. This is the B field on the PDAMP entry and can either be a real value or a reference to an existing field definition. This property is optional.

Dof at Node 1 Dof at Node 2

Defines which degree of freedom this value will be attached to at each node. This can be set to UX, UY, UZ, RX, RY, or RZ. These define the settings of the C1 and C2 field on the CDAMP1 entry. These properties are required.

User Defined Coordinate Number of a User Defined Coordinate system, used only for Explicit System Number Nonlinear (SOL 700). This property is optional.

Main Index

Chapter 2: Building A Model 143 Element Properties

1D - Damper - Viscous (CVISC) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

1D

Damper

Viscous

Bar 2

Use this form to create a CVISC element and a PVISC property. This defines a viscous damper element of the structural model. Prop Name

Main Index

Description

Extensional Viscous Coefficient

This is the C1 field on the PVISC entry. This property can either be a real value or a reference to an existing field definition. This property is optional.

Rotational Viscous Coefficient

This is the C2 field on the PVISC entry. This property can either be a real value or a reference to an existing field definition. This property is optional.

144

Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Gap - Adaptive / Non Adaptive (CGAP) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

1D

Gap

Adaptive

Bar 2

Nonadaptive

Use this form to create a CGAP element and a PGAP property. This defines a gap or frictional element of the structural model for non-linear analysis. Prop Name

Main Index

Description

Gap Orientation

Defines the local element coordinate system for this element that can be defined in one of three ways. If the two end nodes of the gap are not coincident, then the Gap Orientation can reference a vector or a node ID. This local x-axis would then run between the two end nodes and the orientation information would define the local xy plane. However, if the two end nodes are coincident, then the Gap Orientation refers to an existing coordinate system definition and will be used as the local element coordinate system. This Gap Orientation defines the settings of the X1, X2, X3, G0, and CID fields on the CGAP entry. This property is required.

Initial Opening

Defines the initial opening of the gap element. The nodal coordinates are only used to define the closure direction. This property is the U0 field on the PGAP entry and can be either a real value or a reference to an existing field definition. This property is optional.

Preload

Defines an initial preload across an initially closed gap. For example, this can be used for initial thread loading. If the gap is initially open, setting this value to the initial opening stiffness will improve the solution convergence. This is the F0 field on the PGAP entry and can either be a real value or a reference to an existing field definition. This property is optional.

Closed Stiffness Open Stiffness

Defines the artificial stiffness of the gap when the gap is open or closed. The closed stiffness should be chosen to closely match the stiffness of the surrounding elements. The open stiffness should be approximately 10 orders of magnitude less. These properties are the Ka and Kb fields on the PGAP entry and can either be real value or references to existing field definitions. The closed stiffness property is required. The opened stiffness property is optional.

Chapter 2: Building A Model 145 Element Properties

Prop Name Sliding Stiffness

Defines the artificial shear stiffness of the element when the element is closed. This is the Kt field on the PGAP entry. This property can be either a real value or a reference to an existing field definition. This property is optional.

Static Friction

Defines the static friction coefficient. This property is the MU1 field on the PGAP entry. This value is optional and can be a real scalar or a spatially varying real scalar field. Not applicable for Nonadaptive model.

Kinematic Friction

Defines the kinematic friction coefficient. This property is the MU2 field on the PGAP entry. This value is optional and can be a real scalar or a spatially varying real scalar field. Not applicable for Nonadaptive model.

Max Penetration

Defines the maximum allowable penetration. This property is the TMAX field on the PGAP entry. This value is optional and can be a real scalar or a spatially varying real scalar field.

Max Adjust Ratio

Defines the maximum allowable adjustment ratio. This property is the MAR field on the PGAP entry. This value is optional and can be a real scalar or a spatially varying real scalar field. Not applicable for Nonadaptive model.

Penet. Lower Bound

Defines the lower bound for the allowable penetration. This is the TRMIN field on the PGAP entry. This value is optional and can be a real scalar or a spatially varying real scalar field. Not applicable for Nonadaptive model.

Friction Coeff. y

Defines the coefficient of friction when sliding occurs along this element in the local y and z directions. These are the MU1 and MU2 fields on the PGAP entry and can be either real values or references to existing field definitions. These properties are optional.

Friction Coeff. Z

Main Index

Description

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Scalar Mass (CMASS1) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Create Modify

1D

1D Mass

Option(s)

Topologies Bar/2

Use this form to create CMASS1 elements and a PMASS property. This defines a scalar mass element of the structural model.

Prop Name

Main Index

Description

Mass

Defines the translation mass or rotational inertia value to be applied. This property is the M field on the PMASS entry and can either be a real value or a reference to an existing field definition. This property is required.

Dof at Node 1 Dof at Node 2

Defines which degree of freedom this value will be attached to at each node. These can be set to UX, UY, UZ, RX, RY, or RZ and defines the settings of the C1 and C2 field on the CMASS1 entry. These properties are required.

Chapter 2: Building A Model 147 Element Properties

1D - PLOTEL This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Create Modify

1D

PLOTEL

Option(s)

Topologies Bar/2

Use this form to create PLOTEL elements. No actual properties are needed to define this property set. These elements are written to the MSC Nastran input deck for MSC Nastran plotting purposes only and are not structural in nature and not used by the actual analysis.

Main Index

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Patran Interface to MSC Nastran Preference Guide Element Properties

1D - Bush (CBUSH) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

1D

Bush

Scalar

Bar/2

CBUSH/PBUSH/PBUSHT element property sets are created with this option for defining a scalar bush joint, which is a generalized spring-damper structural element. If frequency dependent or nonlinear force deflection properties are supplied, the PBUSHT entry will be written. Otherwise it will not be written. This is a list of Input Properties available. Use the menu scroll bar on the Input Properties form to view these properties. Prop Name Bush Orientation

Description Element orientation strategy keys off of CID specification. If CID is blank, the element x-axis lies along the line which joins the elements grid points (GA, GB Element Properties/Application Region). The X-Y plane is determined by specifying the Bush Orientation. If a vector input is given, these components define an orientation vector v from the first grid point (GA) of the element in the displacement coordinate system at that point (GA). If the Bush Orientation references a grid point ID (Value), this orientation point forms an orientation vector which extends from the first element grid point to the orientation point. If a CID ≥ 0 is specified for Bush Orientation System, the element X,Y, and Z axes are aligned with the coordinate system principal axes. If the CID is for a cylindrical or spherical coordinate system, the first elemental grid point (GA) is used to locate the system. If CID = 0, the elemental coordinate system is the Basic Coordinate System. If no orientation is specified in any form, the element x-axis is along the line which connects the element’s grid points. The material property inputs for this condition must be limited to simple axial and torsional stiffness and damping (k1,k4,B1,B4).

Main Index

Offset Location

Offset Location (0.0 ≤ s ≤ 1.0) specifies the spring-damper location along the line from GRIDGA to GRIDGB by setting the fraction of the distance from GRIDGA. s=0.50 centers the springdamper.

Offset Orientation System

Specifies the coordinate system used to locate the spring-damper offset when it is not on the line from GRIDGA to GRIDGB.

Chapter 2: Building A Model 149 Element Properties

Prop Name

Description

Offset Orientation Vector

Provides the location of the spring-damper in space relative to the offset coordinate system. If the offset orientation system is -1 or blank, the offset orientation vector is ignored.

Spring Constant i Stiffness Frequency Depend i

Defines the stiffness associated with a particular degree of freedom. These are the Ki fields of the PBUSH entry. This property is defined in terms of force per unit displacement and is defined as a real value A reference to an existing field definition for defining stiffness vs. frequency writes the TKIDi fields in the PBUSHT entry.

Stiffness Force/Displacement i Defines the nonlinear force vs deflection curves for each degree of freedom of the spring-damper system. These are the TKNIDi fields of the PBUSHT entry. Damping Coefficient i Defines the force per velocity damping value for each degree of Damping Frequency Depend i freedom. These are the Bi fields of the PBUSH entry. A reference to an existing field definition for defining damping vs. frequency writes the TBIDi fields in the PBUSHT entry.

Main Index

Structural Damping Structural Damping Frequency Depend i

Defines the non-dimensional structural damping coefficient (GEi fields of the PBUSH entry). A reference to an existing field definition for defining damping vs. frequency writes the TKGEIDi fields to the PBUSHT entry.

Stress Recovery Translation Stress Recovery Rotation Strain Recovery Translation Strain Recovery Rotation

Stress and Strain Recovery Coefficients. The element stress are computed by multiplying the stress coefficients with the recovered element forces. The element strains are computed by multiplying the strain coefficients with the recovered element strains. This defines the SA, ST, EA & ET fields on the PBUSH entry.

Force-Deflection Curve Rule

Force deflection curve rule - writes FDC field of PBUSHT. See the MSC Nastran Quick Start manual for details.

Fuse Behavior

Fuse behavior. Writes the FUSE field of PBUSHT

Fuse Direction

Fuse direction. Writes the DIR field of PBUSHT.

Fuse Failure Mode

Failure mode. Writes the OPTION field of PBUSHT.

Lower Failure Bound Upper Failure Bound

Lower and Upper failure bound. Writes the LOWER and UPPER fields of the PBUSHT entry.

FRATE-K Drop Scale Factor

Fuse stiffness retention factor. Writes the FSRS field of the PBUSHT entry.

Grid A Rotation

Large rotation flag. Writes the LRGR field of the PBUSHT entry.

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1D- Bush (CBUSH2D/PBUSH2D) This describes the Input Properties available from the Element Properties form and the following options are chosen. Action

Dimension

Type

Option(s)

Topologies

Create Modify

1D

Bush

2D Linear/Non Linear Bar/2

This creates CBUSH2D/PBUSH2D entries. Following is a list of Input Properties available. Use the menu scroll bar on the Input Properties form to view these properties.

Prop Name

Main Index

Description

Bush Orientation

String pull down indicating the plane must be supplied as the XY, YZ, or ZX plane of the given coordinate system.

Orientation System

Coordinate in which Orientation plane is defined. Select data box to allowed graphical selection of coordinate.

Stiffness K11

Nominal stiffness in T1 rectangular direction. Required!

Stiffness K22

Nominal stiffness in T2 rectangular direction. Required!

[Damping B11]

Nominal damping in T1 rectangular direction. Default = 0.0

[Damping B22]

Nominal damping in T2 rectangular direction. Default = 0.0

[Force M11]

Nominal acceleration-dependent force in T1 rectangular direction. Default = 0.0

[Force M22]

Nominal acceleration-dependent force in T2 rectangular direction. Default = 0.0

[Inner Journal Diameter BDIA]

Inner journal diameter. Real > 0.0

[Damper Length BLEN]

Damper length. Required if inner journal diameter given! Real > 0.0

[Damper Radial Clearance BCLR]

Damper radial clearance. Required if inner journal diameter given! Real > 0.0

[Solution Option SOLN]

Pulldown String - Solution Option: Long or Short (Default = Long)

[Lubricant viscosity VISCO]

Lubricant viscosity. Required if inner journal diameter given! Real > 0.0

[Lubricant Vapor Pressure PVAPCO]

Lubricant vapor pressure. Required if inner journal diameter given! Real.

[Number of Lubricant Ports NPORT]

Integer pull down: Number of lubricant ports. 1 or 2

Chapter 2: Building A Model 151 Element Properties

Prop Name

Main Index

Description

[Boundary Pressure for Port 1]

Boundary pressure for port 1. Required if NPORT = 1. Real >= 0.0

[Angular Positions for Port 1]

Angular position for port 1. (0.0 0.0, overlap between bodies. For values Beam Library (p. 506) in the Patran Reference Manual. Once one or more beam sections have been defined, these can be selected in the section data box on the element properties form.

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Chapter 2: Building A Model 233 3DBeam Modeling

Supplied Functions

I-Beam - Six dimensions -- lower flange thickness (t1), upper flange thickness (t2),lower flange width (w1), upper flange width (w2), overall height (H), and web thickness (t)-- allows for symmetric or unsymmetrical I-beam definition.

Angle - Open section, four dimensions -- overall height (H), overall width (W), horizontal flange thickness (t1), vertical flange thickness (t2).

Tee - Four dimensions -- overall height (H), overall width (W), horizontal flange thickness (t1), vertical flange thickness (t2).

Solid-Rod - Solid section, one dimension -- radius (R).

Box-Symmetric - Closed section, four dimensions -- overall height (H), overall width (W), top and bottom flange thicknesses (t1), side flange thicknesses (t2).

Tube - Closed section, two dimensions -- outer radius (R1), inner radius (R2).

Channel - Open section, four dimensions -- overall height (H), overall width (W), top and bottom flange thicknesses (t1), shear web thickness (t).

Bar - Solid section, two dimensions -- height (H) and width (W).

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Box-Unsymmetrical - Closed section, six dimensions -- overall height (H), overall width (W), top flange thickness (t1), bottom flange thickness (t2), right side flange thickness (t3), left side flange thickness (t4).

Hat - Four dimensions -- overall height (H), top of hat flange width (W), bottom of hat flange width for one side (W1), thickness (t).

H-Beam - Four dimensions -- overall height (H), width between inner edges of vertical flanges (W), horizontal shear web thickness (t), and thickness of one vertical flange (W1/2). Cross - Four dimensions -- overall height (H), vertical flange thickness (t), horizontal flange thickness (t2), length of free horizontal flange for one side (W/2).

Z-Beam - Four dimensions -- overall height (H2), height of vertical flange between as measured between horizontal flanges, length of free horizontal flange for one side (W), thickness (t1). Hexagonal - Solid section, three dimensions -- overall height (H), overall width (W), horizontal distance from side vertex to top or bottom surface vertex along the common edge (i.e., diagonal edge hypotenuse times the cosine of the exterior diagonal angle).

Cross Section Orientation The Bar Orientation data box on the Input Properties form is used to define how the y-axis of the beam cross section is oriented in space. By default the Value Type is Vector. This tells MSC ⁄Nastran that the cross section y-axis lies in the plane defined by the beam’s x-axis (the line connecting the two node points) and this vector. The Value Type pop up menu may be changed to Node ID. In this case the y-axis lies in the plane defined by the x-axis and the selected node. When the Value Type is Vector and the Bar Orientation data box is selected the following select box appears on the screen. These select tools provide different options for defining vectors. They are discussed in more detail in the Select Menu (p. 34) in the Patran Reference Manual.

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Chapter 2: Building A Model 235 3DBeam Modeling

Entry

Description These three tools define the orientation vector as the 1 (x), 2(y), or 3(z) axis of a selected coordinate system. This is a convenient way to specify the orientation when it is aligned with one of the three axes of a rectangular coordinate system. When the system is not rectangular (e.g. cylindrical) these tools may not provide the desired definition because the defined vector does not change direction at different points in space--these tools just provide an alternate way to define a global vector.

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Entry

Description This tool may be used to define a general vector with respect to an alternate coordinate system. When this icon is picked, the select menu changes to the one on the right.

These tools provide different ways to define vectors. In addition, the user is requested to select a coordinate system in which this vector is defined. The simplest list processor syntax that appears in the databox for a vector in an alternate coordinate system is coord cord_id (e.g. coord 3). In many cases it is easy to simply type a definition in this form into the Bar Orientation databox.

After the orientation has been defined, there are two ways to verify its correctness in Patran. The first option is in the Element Properties application. By selecting the Show Action, the Definition of X Y Plane property, and Display Method Vector Plot, the vectors defining the orientation will be shown on the model. A second option can be used when the Beam Library has been used to define the beam cross section. There is an option on the Display form Display>LBC/Element Property Attributes (p. 385) in the Patran Reference Manual called Beam Display. The menu allows different display options for displaying an outline of the defined cross section on the model in the correct location and orientation. Users should be aware of one difference between the Patran and MSC Nastran definitions for cross section orientation. In Patran the orientation is completely independent of the analysis coordinate system at the beam nodes. In MSC Nastran, the orientation vector is assumed to be defined in the same system as the analysis system at the first node of the beam. In Patran it is perfectly permissible to define the

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Chapter 2: Building A Model 237 3DBeam Modeling

orientation in a different coordinate system from that analysis system. When the NASTRAN input file is generated, the necessary transformation of this vector to the analysis system at node 1 will be performed. Entry

Description These three tools define the orientation vector as the 1 (x), 2(y), or 3(z) axis of a selected coordinate system. This is a convenient way to specify the orientation when it is aligned with one of the three axes of a rectangular coordinate system. When the system is not rectangular (e.g. cylindrical) these tools may not provide the desired definition because the defined vector does not change direction at different points in space-these tools just provide an alternate way to define a global vector.

This tool may be used to define a general vector with respect to an alternate coordinate system. When this icon is picked, the select menu changes to the one on the right.

These tools provide different ways to define vectors. In addition, the user is requested to select a coordinate system in which this vector is defined. The simplest list processor syntax that appears in the databox for a vector in an alternate coordinate system is coord cord_id (e.g. coord 3). In many cases it is easy to simply type a definition in this form into the Bar Orientation databox.

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Cross Section End Offsets Two data boxes are provided on the Element Properties, Input Properties form to optionally define an offset from either node 1 to the cross section centroid (Offset @ Node 1) or from node 2 to the cross section centroid (Offset @ Node 2). The same select menu tools are available for defining these vectors. One difference between the orientation definition and the offset definitions, however, is that for the offset the magnitude of the vector is important. Because of this, the select menu tools are usually not very convenient. Typically, offsets are defined by typing the definition (e.g or coord n>) into the appropriate data box. Two options are available for verifying the definitions of offsets; these options are very similar to those for orientations. The Element Properties, Show Action will allow the end offsets to be displayed as vectors on the model. This option is not especially useful because the vector plot shows only the direction of the offset, not the magnitude of the offset. It is usually much more useful to view the Beam Display menu on the Display form Display>LBC/Element Property Attributes (p. 385) in the Patran Reference Manual to select the display option with offsets. The viewport will then show the beam displayed in both the offset and non-offset positions.

Stiffened Cylinder Example Figure 2-1 shows a simple example of a circular cylinder stiffened with Z-stiffeners. The cross section

was defined by selecting the Beam Library icon on the Element Properties/Input Properties form. The Z cross section was selected on the Beam Library form, the cross section dimensions input, a section name input, and the Apply button pushed. On the Input Properties form, the Use Beam Section toggle is set to ON. The defined section name is selected in the [Section Name] data box. The string coord 1 is typed into the Bar Orientation data box to align the cross section orientation with the radial direction of the global, cylindrical system. Similarly, the strings coord 1 and coord 1

Main Index

Chapter 2: Building A Model 239 3DBeam Modeling

typed into the Offset @ Node 1 and Offset @ Node 2 data boxes define the end offsets to be radially inward.

T Z1

Y Z

Figure 2-1

Main Index

X

Stiffened Cylinder

R

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Patran Interface to MSC Nastran Preference Guide Loads and Boundary Conditions

2.9

Loads and Boundary Conditions The Loads and Boundary Conditions form will appear when the Loads/BCs toggle, located on the Patran main form, is chosen. When creating a load and boundary condition there are several option menus. The selections made on the Loads and Boundary Conditions menu will determine which load and boundary conditions form appears, and ultimately, which MSC Nastran loads and boundary conditions will be created. The following pages give an introduction to the Loads and Boundary Conditions form and details of all the loads and boundary conditions supported by the Patran MSC Nastran Analysts Preference.

Loads & Boundary Conditions Form This form appears when Loads/BCs is selected on the main menu. The Loads and Boundary Conditions form is used to provide options to create the various MSC Nastran loads and boundary conditions. For a definition of full functionality, see Loads and Boundary Conditions Application (p. 5) in the Patran Reference Manual. Options for defining slide line contact are also accessed from this main Loads and Boundary Conditions form. For more information see Defining Contact Regions, 276.

Main Index

Chapter 2: Building A Model 241 Loads and Boundary Conditions

Main Index

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Patran Interface to MSC Nastran Preference Guide Loads and Boundary Conditions

Entry

Description

Object

These three tools define the orientation vector as the 1 (x), 2(y), or 3(z) axis of a selected coordinate system. This is a convenient way to specify the orientation when it is aligned with one of the three axes of a rectangular coordinate system. When the system is not rectangular (e.g. cylindrical) these tools may not provide the desired definition because the defined vector does not change direction at different points in space-these tools just provide an alternate way to define a global vector.

Type

Defines what type of region is to be loaded. The available options depend on the selected Object. The general selections can be Nodal, Element Uniform, or Element Variable. Nodal is applied explicitly to nodes. Element Uniform defines a constant value to be applied over an entire element, element face, or element edge. Element Variable defines a value that varies across an entire element, element face, or element edge.

Current Load Case

Current Load Case type is set on the Load Case menu. When the Load Cases toggle located on the main menu is chosen, the Load Cases menu will appear. Under Load Case Type, select either Static or Time Dependent, then enter the name of the case, and click on the Apply button.

Input Data

Generates either a Static, 244 or Time Dependent, 247 Input Data form, depending on the current Load Case Type.

The following table outlines the options when Create is the selected Action. Object • Displacement / Velocty / Acceleration

Type • Nodal • Element Uniform • Element Variable

• Force

• Nodal

• Pressure

• Element Uniform • Element Variable

• Temperature

• Nodal • Element Uniform • Element Variable

Main Index

• Inertial Load

• Element Uniform

• Initial Displacement

• Nodal

• Initial Velocity

• Nodal

Chapter 2: Building A Model 243 Loads and Boundary Conditions

Object • Distributed Load

Type • Element Uniform • Element Variable

• CID Distributed Load

• Element Uniform • Element Variable

• Total Load

• Element Uniform

• Contact

• Element Uniform

• Crack (VCCT)

• Nodal

• Initial Plastic Strain

• Element Uniform

• Initial Stress

• Element Uniform

• Initial Temperature

• Nodal

• Planar Rigid Wall *

• Nodal

• Init. Rotation Field *

• Nodal

* For SOL 700 only.

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Static This subordinate form appears when the Input Data button is selected on the Loads and Boundary Conditions form and the Current Load Case Type is Static. The Current Load Case Type is set on the Load Case form. For more information see Loads & Boundary Conditions Form, 240. The information on the Input Data form will vary depending on the selected Object. Defined below is the standard information found on this form.

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Chapter 2: Building A Model 245 Loads and Boundary Conditions

Entry

Main Index

Description

Load/BC Set Scale Factor

Defines a general scaling factor for all values defined on this form. The default value is 1.0. Primarily used when field definitions are used to define the load values.

Input Data

Input Data in this section will vary. See Object Tables, 248 for detailed information.

Spatial Fields

When specifying real values in the Input Data entries, spatial fields can be referenced. All defined spatial fields currently in the database are listed. If the input focus is placed in the Input Data entry and a spatial field is selected by clicking in this list, a reference to that field will be entered in the Input Data entry.

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Patran Interface to MSC Nastran Preference Guide Loads and Boundary Conditions

Entry

Main Index

Description

FEM Dependent Data

This button will display a Discrete FEM Fields input form to allow field creation and modification within the loads/bcs application. Visible only when focus is set in a databox which can have a DFEM field reference.

Analysis Coordinate Frame

Defines the coordinate frame used to interpret the degree-of-freedom data defined on this form. This only appears on the form for Nodal type loads. This can be a reference to any existing coordinate frame definition.

Chapter 2: Building A Model 247 Loads and Boundary Conditions

Time Dependent This subordinate form appears when the Input Data button is selected on the Loads and Boundary Condition form and the Current Load Case Type is Time Dependent. The Current Load Case Type is set on the Load Case form. For more information see Loads & Boundary Conditions Form, 240 and Load Cases, 275. The information on the Input Data form will vary, depending on the selected Object. Defined below is the standard information found on this form.

Entry

Main Index

Description

Load/BC Set Scale Factor

Defines a general scaling factor for all values defined on this form.The default value is 1.0. Primarily used when field definitions are used to define the load values.

Spatial Dependence

Input Data in this section will vary. See Object Tables, 248 for detailed information.

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Patran Interface to MSC Nastran Preference Guide Loads and Boundary Conditions

Entry

Description

Spatial Fields

When specifying real values in the Input Data entries, spatial fields can be referenced. All defined spatial fields currently in the database are listed. If the input focus is placed in the Input Data entry and a spatial field is selected by clicking in this list, a reference to that field will be entered in the Input Data entry.

Time Dependent Fields

When specifying time dependent values in the Input Data entries, timedependent fields can be referenced. All defined time-dependent fields currently in the database are listed. If the input focus is placed in the Input Data entry and a time-dependent field is selected by clicking in this list, a reference to that field will be entered in the Input Data entry.

FEM Dependent Data...

This button will display a Discrete FEM Fields input form to allow field creation and modification within the loads/bcs application. Visible only when focus is set in a databox which can have a DFEM field reference.

Analysis Coordinate Frame

Defines the coordinate frame to be used to interpret the degree-offreedom data defined on this form. This only appears on the form for Nodal type loads. This can be a reference to any existing coordinate frame definition.

Object Tables These are areas on the static and transient input data forms where the load data values are defined. The data fields that appear depend on the selected load Object and Type. In some cases, the data fields also depend on the selected Target Element Type. The following Object Tables outline and define the various input data that pertains to a specific selected object: Displacement / Velocty / Acceleration Object

Type

Analysis Type

Option

Displacement Velocity Acceleration

Nodal

Structural

Standard

Creates MSC Nastran SPC1 and SPCD Bulk Data for Displacement entries. All non blank entries will cause an SPC1 entry to be created. If the specified value is not 0.0, an SCPD entry will also be created to define the non zero enforced displacement or rotation. Phase angle specifications will create DPHASE entries for all corresponding non blank translational or rotational data in frequency response analysis. Displacement, Velocity and Acceleration LBCs used in frequency response / dynamic analysis also define the RLOAD1 entries with DISP, VELOC, and ACCEL keywords, respectively. For frequency response analysis, the LBCs must reference a frequency range of interest defined as a non-spatial frequency field such that a TABLEDi entry is created. The load case needs to be defined as Time/Frequency dependent to do this. Values given via this option are total enforced values. For relative enforced values used in SOL 400, see the description for the Relative Displacement option below.

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Chapter 2: Building A Model 249 Loads and Boundary Conditions

Input Data

Description

Translations (T1,T2,T3)

Defines the total enforced translational values. These are in model length units.

Rotations (R1,R2,R3)

Defines the total enforced rotational values. These are in radians.

Translational Phase Angles (Tth1,Tth2,Tth3)

Defines the phase angle for out-of-phase loading in frequency response analysis for the translational values. These are in degrees.

Rotational Phase Angles (Rth1,Rth2,Rth3)

Defines the phase angle for out-of-phase loading in frequency response analysis for the rotational values. These are in degrees.

Object

Type

Analysis Type

Dimension

Displacement

Element Uniform

Structural

3D

Element Variable Applies a zero or nonzero total displacement boundary condition to the face of solid elements. The primary use of this boundary condition is to apply constraints to p-elements; but it may also be used for standard solid elements. If applied to a p-element solid, the appropriate FEFACE and GMBC entries are created. If applied to a standard solid element, the appropriate SPC1 and SPCD entries are created. In frequency response analysis, the phase angles are written as DPHASE entries. See comments above for nodal displacements. Input Data

Description

Translations (T1,T2,T3)

Defines the enforced translational displacement values. These values are in model-length units.

Translation Phases (Tth1,Tth2,Tth3)

Defines the phase angle for out-of-phase loading in frequency response analysis for the translational displacement values. These are in degrees.

Object

Type

Analysis Type

Option

Displacement

Nodal

Structural

Relative Displacement

Applies a zero or nonzero relative displacement boundary condition as opposed to a total magnitude. This is used in SOL 400 only with multiple steps and not applicable to other solution sequences. This LBC will be ignored if present in a referenced load case for solution sequences other than SOL 400. The appropriate SPC1 and SPCR entries are created. For example, if a DOF is specified on a SPCR with 0.0 for step 2, the relative displacement of this DOF for step 2 with respective to step 1 is 0.0. The total displacement of step 2 is 0.2 if the solution of step 1 for this DOF is 0.2.

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Input Data

Description

Relative Translations (T1,T2,T3) Defines the relative enforced translational displacement values in vector form, each value separated by a comma between the brackets . If no enforced translation is to be specified, the particular component should be left blank. Relative Rotations (R1,R2,R3)

Main Index

Defines the relative enforced rotational displacement values in vector form, each value separated by a comma between the brackets . If no enforced rotation is to be specified, the particular component should be left blank.

Chapter 2: Building A Model 251 Loads and Boundary Conditions

Force Object

Type

Analysis Type

Force

Nodal

Structural

Creates MSC Nastran FORCE and MOMENT Bulk Data entries. Creates the DPHASE entries in frequency response analysis when specifying phase angles for out-of-phase loading. RLOAD1 entries are created for dynamic analysis and reference the appropriate FORCE entries. For frequency response analysis, the force LBCs must reference a frequency range of interest defined as a non-spatial frequency field such that a TABLEDi entry is created. The load case needs to be defined as Time/Frequency dependent to do this. Input Data

Main Index

Description

Force (F1,F2,F3)

Defines the applied forces in the translation degrees of freedom. This defines the N vector and the F magnitude on the FORCE entry.

Moment (M1,M2,M3)

Defines the applied moments in the rotational degrees of freedom. This defines the N vector and the M magnitude on the MOMENT entry.

Force Phase Angles (Fth1,Fth2,Fth3)

Defines the phase angle for out-of-phase loading in frequency response analysis for the corresponding force components. These are in degrees.

Moment Phase Angles (Mth1,Mth2,Mth3)

Defines the phase angle for out-of-phase loading in frequency response analysis for the corresponding moment components. These are in degrees.

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Pressure Object

Type

Analysis Type

Dimension

Pressure

Element Uniform

Structural

2D

Creates MSC Nastran, PLOAD4, PLOADX1, or FORCE Bulk Data entries. Input Data

Description

Top Surf Pressure

Defines the top surface pressure load on shell elements using a PLOAD4 entry. The negative of this value defines the P1, P2, P3, and P4 values. These values are all equal for a given element, producing a uniform pressure field across that face.

Bot Surf Pressure

Defines the bottom surface pressure load on shell elements using a PLOAD4 entry. This value defines the P1 through P4 values.These values are all equal for a given element, producing a uniform pressure field across that face.

Edge Pressure

For Axisymmetric Solid elements (CTRIAX6), defines the P1 through P3 values on the PLOADX1 entry where THETA on that entry is defined as zero. For other 2D elements, this will be interpreted as a load per unit length (i.e. independent of thickness) and converted into equivalent nodal loads (FORCE entries). If a scalar field is referenced, it will be evaluated at the middle of the application region.

Object

Type

Analysis Type

Dimension

Pressure

Element Uniform

Structural

3D

Creates MSC Nastran PLOAD4 Bulk Data entries. Input Data Pressure

Description Defines the face pressure value on solid elements using a PLOAD4 entry. This defines the P1, P2, P3, and P4 values. If a scalar field is referenced, it will be evaluated once at the center of the applied region.

Object

Type

Analysis Type

Dimension

Pressure

Element Variable

Structural

2D

Creates MSC Nastran, PLOAD4, PLOADX1, or FORCE Bulk Data entries.

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Chapter 2: Building A Model 253 Loads and Boundary Conditions

Input Data

Description

Top Surf Pressure

Defines the top surface pressure load on shell elements using a PLOAD4 entry. The negative of this value defines the P1, P2, P3, and P4 values. If a scalar field is referenced, it will be evaluated separately for the P1 through P4 values.

Bot Surf Pressure

Defines the bottom surface pressure load on shell elements using a PLOAD4 entry. This value defines the P1 through P4 values. If a scalar field is referenced, it will be evaluated separately for the P1 through P4 values.

Edge Pressure

For Axisymmetric Solid elements (CTRIAX6), defines the P1 through P3 values on the PLOADX1 entry where THETA on that entry is defined as zero. For other 2D elements, this will be interpreted as a load per unit length (e.g., independent of thickness) and converted into equivalent nodal loads (FORCE entries). If a scalar field is referenced, it will be evaluated independently at each node.

Object

Type

Analysis Type

Dimension

Pressure

Element Variable

Structural

3D

Creates MSC Nastran PLOAD4 Bulk Data entries. Input Data Pressure

Main Index

Description Defines the face pressure value on solid elements using a PLOAD4 entry. This defines the P1, P2, P3, and P4 values. If a scalar field is referenced, it will be evaluated separately for each of the P1 through P4 values.

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Temperature Object

Type

Analysis Type

Temperature

Nodal

Structural

Creates MSC Nastran TEMP Bulk Data entries. Input Data

Description

Temperature

Defines the T fields on the TEMP entry.

Object

Type

Analysis Type

Dimension

Temperature

Element Uniform

Structural

1D

Writes the TEMPP1 entry. For 2D Target Elements, T1/T2 or TBAR/TPRIME are written to the TEMPP1 entry but not both. For Equivalent Section shell properties or shell properties that have Z1/Z2 defined, T1/T2 is written and TBAR/TPRIME left blank on the TEMPP1 entry. Nastran determines the correct TPRIME. For all other shell properties TBAR/TPRIME are written and T1/T2 left blank. TBAR/TPRIME are computed by Patran from T1/T2 using the thickness property value. This is for Element Variable Temperature LBCs. For Element Uniform Temperature LBC, only TBAR is written or necessary. All others fields are left blank. Creates MSC Nastran TEMPRB Bulk Data entries. Input Data Temperature

Description Defines a uniform temperature field using a TEMPRB entry. The temperature value is used for both the TA and TB fields. The T1a, T1b, T2a, and T2b fields are all defined as 0.0.

Object

Type

Analysis Type

Dimension

Temperature

Element Uniform

Structural

2D

Creates MSC Nastran TEMPP1 Bulk Data entries. Input Data Temperature

Main Index

Description Defines a uniform temperature field using a TEMPP1 entry. The temperature value is used for the T field. The gradient through the thickness is defined to be 0.0.

Chapter 2: Building A Model 255 Loads and Boundary Conditions

Object

Type

Analysis Type

Dimension

Temperature

Element Variable

Structural

1D

Creates MSC Nastran TEMPRB Bulk Data entries. Input Data

Description

Centroid Temp

Defines a variable temperature file using a TEMPRB entry. A field reference will be evaluated at either end of the element to define the TA and TB fields.

Axis-1 Gradient

Defines the temperature gradient in the 1 direction. A field reference will be evaluated at either end of the element to define the T1a and T1b fields.

Axis-2 Gradient

Defines the temperature gradient in the 2 direction. A field reference will be evaluated at either end of the element to define the T2a and T2b fields.

Object

Type

Analysis Type

Dimension

Temperature

Element Variable

Structural

2D

Creates MSC Nastran TEMPP1 Bulk Data entries. Input Data

Description

Top Surf Temp

Defines the temperature on the top surface of a shell element. The top and bottom values are used to compute the average and gradient values on the TEMPP1 entry.

Bot Surf Temp

Defines the temperature on the bottom surface of a shell element. The top and bottom values are used to compute the average and gradient values on the TEMPP1 entry.

Object

Type

Analysis Type

Dimension

Temperature

Element Uniform Element Variable

Structural

1D, 2D, 3D

This option applies only to the P-formulation elements. A TEMPF and DEQATN entry are created for the constant temperature case. A TEMPF and TABLE3D entry are created for the case when a spatial field is referenced. Writes the TEMPP1 entry. For 2D Target Elements, T1/T2 or TBAR/TPRIME are written to the TEMPP1 entry but not both. For Equivalent Section shell properties or shell properties that have Z1/Z2 defined, T1/T2 is written and TBAR/TPRIME left blank on the TEMPP1 entry. Nastran determines the correct TPRIME. For all other shell properties TBAR/TPRIME are written and T1/T2 left blank. TBAR/TPRIME are computed by Patran from T1/T2 using the thickness property value. This is for Element Variable Temperature LBCs. For Element Uniform Temperature LBC, only TBAR is written or necessary. All others fields are left blank.

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Input Data Temperature

Main Index

Description Defines the temperature or temperature distribution in the element.

Chapter 2: Building A Model 257 Loads and Boundary Conditions

Inertial Load Object

Type

Analysis Type

Inertial Load

Element Uniform

Structural

Creates MSC Nastran GRAV and RFORCE Bulk Data entries. Input Data

Description

Trans Accel (A1,A2,A3)

Defines the N vector and the G magnitude value on the GRAV entry.

Rot Velocity (w1,w2,w3)

Defines the R vector and the A magnitude value on the RFORCE entry.

Rot Accel (a1,a2,a3)

Defines the R vector and the RACC magnitude value on the RFORCE entry.

The acceleration and velocity vectors are defined with respect to the input analysis coordinate frame. The origin of the rotational vectors is the origin of the analysis coordinate frame. Note that rotational velocity and rotational acceleration cannot be defined together in the same set.In generating the GRAV and RFORCE entries, the interface produces one GRAV and/or RFORCE entry image for each Patran load set. Initial Displacement

Object

Type

Analysis Type

Initial Displacement

Nodal

Structural

Creates a set of MSC Nastran TIC Bulk Data entries. Input Data

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Description

Translations (T1,T2,T3)

Defines the U0 fields for translational degrees of freedom on the TIC entry. A unique TIC entry will be created for each non blank entry.

Rotations (R1,R2,R3)

Defines the U0 fields for rotational degrees of freedom on the TIC entry. A unique TIC entry will be created for each non blank entry.

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Initial Velocity Object

Type

Analysis Type

Initial Velocity

Nodal

Structural

Creates a set of MSC Nastran TIC Bulk Data entries. Input Data

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Description

Trans Veloc (v1,v2,v3)

Defines the V0 fields for translational degrees of freedom on the TIC entry. A unique TIC entry will be created for each non blank entry.

Rot Veloc (w1,w2,w3)

Defines the V0 fields for rotational degrees of freedom on the TIC entry. A unique TIC entry will be created for each non blank entry.

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Distributed Load Object

Type

Analysis Type

Dimension

Distributed Load

Element Uniform Element Variable

Structural

1D

Defines distributed force or moment loading along beam elements using MSC Nastran PLOAD1 entries. The coordinate system in which the load is applied is defined by the beam axis and the Bar Orientation element property. The Bar Orientation must be defined before this Distributed Load can be created. If the Bar Orientation is subsequently changed, the Distributed Load must be updated manually if necessary. For the element variable type, a field reference is evaluated at each end of the beam to define a linear load variation. Input Data

Description

Edge Distributed Load (f1,f2,f3)

Defines the FXE, FYE, and FZE fields on three PLOAD1 entries.

Edge Distributed Moment (m1,m2,m3)

Defines the MXE, MYE, and MZE fields on three PLOAD1 entries.

Object

Type

Analysis Type

Dimension

Distributed Load

Element Uniform Element Variable

Structural

2D

Defines a distributed force or moment load along the edges of 2D elements. The coordinate system for the load is defined by the surface or element edge and normal. The x direction is along the edge. Positive x is determined by the element corner node connectivity. See Patran Element Library (p. 507) in the Reference Manual - Part III. For example, if the element is a CQUAD4, with node connectivity of 1, 2, 3, 4. The positive x directions for each edge would be from nodes 1 to 2, 2 to 3, 3 to 4, and 4 to 1. The z direction is normal to the surface or element. Positive z is in the direction of the element normal. The y direction is normal to x and z. Positive y is determined by the cross product of the z and x axes and always points into the element. The MSC Nastran entries generated, depend on the element type. For the element variable type, a field reference is evaluated at all element nodes lying on the edge. Input Data

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Description

Edge Distributed Load (f1,f2,f3)

For axisymmetric solid elements (CTRIAX6), the PA, PB, and THETA fields on the PLOADX1 entry are defined. For other 2D elements, the input vector is interpreted as load per unit length and converted into equivalent nodal loads (FORCE entries).

Edge Distributed Moment (m1,m2,m3)

For 2D shell elements, the input vector is interpreted as moment per unit length and converted into equivalent nodal moments (MOMENT entries).

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CID Distributed Load This load is a generalized distributed load whereby directionality is specified by the user in the form a vector where each component of this vector represents the distributed load magnitude for the associated direction. The vector may be constant or a field. This load type is identical to the "Total Load" except the vector components are used as is (i.e., not divided by the area or length of the application region) and that element variable is implemented so that the load can vary across an element. Object

Type

Analysis Type

Dimension

CID Distributed Load

Element Uniform Element Variable

Structural

1D/2D/3D

Input Data

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Description

Load/BC Set Scale Factor

Scale factor by which all components of the distributed forces are multiplied.

Distributed Force (Surface and Edge) (F1,F2,F3)

Defines the applied translational distributed force vector with respect to the specified analysis coordinate frame. In general this provides the magnitudes (for each component) of the uniform load per unit length for 1D or edges of 2D elements or the per unit area on 2D or 3D surfaces.

Spatial Fields

When specifying real values in the Input Data entries, spatial fields can be referenced. All defined spatial fields currently in the database are listed. If the input focus is placed in the Input Data entry and a spatial field is selected by clicking in this list, a reference to that field will be entered in the Input Data entry.

FEM Dependent Data

This button will display a Discrete FEM Fields input form to allow field creation and modification within the loads/bcs application. Visible only when focus is set in a databox which can have a DFEM field reference.

Analysis Coordinate Frame

Coordinate Frame in which the three translational distributed forces are defined.

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Contact Object

Type

Analysis Type

Contact

Element Uniform

Structural

This form is used to define certain data for the MSC Nastran contact entries. Other data entries for contact are defined under the Analysis Application when setting up a job for nonlinear static or nonlinear transient dynamic analysis. A contact table is also supported; by default, all contact bodies initially have the potential to interact with all other contact bodies and themselves. This default behavior can be modified under the Contact Table form, located on the Solution Parameters subform in the Analysis Application when creating a Load Step. Note that contact bodies (BCBODY entry) are written to the MSC Nastran input deck in alphanumeric order, deformable bodies first followed by rigid bodies. The only way to control the order in which bodies are written to the input deck is to name them alphanumerically in the order you wish them to be written.. Preview Rigid Body Motion

After defining the Input Properties you can use the Preview Rigid Body Motion to check the movement of the rigid bodies in place. This is an effective tool for verifying the directions for LBCs. Slideline (SOL 400 and SOL 600)

Input

Description

Penetration Type

If the Penetration Type is One Sided, nodes in the Slave Region are not allowed to penetrate the segments of the Master Region. If Symmetric, in addition, nodes in the Master Region are not allowed to penetrate segments of the Slave Region.

Static Friction Coefficient (MU1)

Coefficient of static friction between the two surfaces.

Stiffness in Stick (FSTIF)

FSTIF is a penalty parameter in the contact formulation. The default value is usually adequate.

Penalty Stiffness Scaling Factor (SFAC)

SFAC is a penalty parameter in the contact formulation. The default value is usually adequate.

Slideline Width (W1)

Slideline Width is constant along the slideline and is used to determine the area for contact stress calculation. This is the Wi field on the BFRIC entry.

Vector Pointing from A vector must be defined which lies in the contact plane and points from the Master to Slave Surface Master region to the Slave region. This vector is used to define the coordinate system on the BCONP entry and the BLSEG entries for each region.

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Deformable Body (SOL 400, SOL 600, and SOL 700 ) .

Description Friction Coefficient (MU)

Coefficient of static friction for this contact body. For contact between two bodies with different friction coefficients, the average value is used.

Define (type of contact) Select 1) Analytic Contact, 2) Contact Area, 3) Exclusion Region, or 4) Glue Deactivation. The Contact Area and Exclusion Region are defined using MSC Nastran entry BCHANGE in the .bdf file, with NODE for Contact Area, and EXCLUDE for Exclusion Region. The Glue Deactivation is defined using MSC Nastran entry UNGLUE.

Main Index

Boundary Type

Select either 1) Analytic, or 2) Discrete. By default, a deformable contact body boundary is defined by the free faces of its elements; this is used by the Discrete option. However, instead of using the free faces of the elements (Discrete), it is possible to use spline surfaces (2D) to represent the outer faces (element faces) of the contact bodies; this is used by the Analytic option. The Analytic option can improve the accuracy of deformabledeformable contact analysis.

Auto Detect Discontinuities

Select this to cause the automatic detection of any discontinuity.

Feature Angle

If the angle between the normals of two touching (adjacent) segments of contact bodies is greater than the Feature Angle, there is a discontinuity there, and the discontinuity (at edge) is preserved.

Select Discontinuities...

See Select Deactivation Region, 263

Edge Contact...

See Edge Contact Subform, 263

Select Contact Area...

See Select Contact Area, 263

Select Exclusion Region...

See Select Exclusion Region, 263

Select Deactivation Region...

See Select Deactivation Region, 263

Chapter 2: Building A Model 263 Loads and Boundary Conditions

Select Discontinuities Subform .

Description Select (entity type)

Choose to either select Geometry or FEM to define any discontinuities.

Detect Discontinuities

Click on this button to determine if there are any discontinuities for the entities that define the Application Region.

Define Discontinuities

Select entities to define the discontinuities.

Edge Contact Subform .

Description Include Outside (Solid Element)

When detecting contact of solid elements (for example, CHEXA elements) use this to include contact of the outside of the elements. For details refer to the BCBODY entry (defines a flexible or rigid contact body in 2D or 3D) of the MSC Nastran QRG. The entry that is used for the BCBODY entry is COPTB (flag that indicates how body surfaces may contact).

Check Layers (Shell Element)

For contact bodies composed of shell elements, this option menu chooses the layers to be checked. Available options are: Top and Bottom, Top Only, Bottom Only. Check Layers and Ignore Thickness combination enters the appropriate flag in the 10th field of the 2nd data block.

Ignore Thickness

Turn this button ON to ignore shell thickness. Check Layers and Ignore Thickness combination enters the appropriate flag in the 10th field of the 2nd data block.

Include Edges (Edges)

Use this to specify how body surfaces may contact. There are three options, Beam/Bar, Free and Hard Shell, or Both. For details refer to the BCBODY entry (defines a flexible or rigid contact body in 2D or 3D) of the MSC Nastran QRG. The entry that is used for the BCBODY entry is COPTB (flag that indicates how body surfaces may contact).

Select Contact Area .

Description Select (entity type)

Choose to either select Geometry or FEM to define the contact area.

Define Contact Area

Select entities to define the contact area.

Select Exclusion Region .

Description Select (entity type)

Choose to either select Geometry or FEM to define the exclusion region.

Define Exclusion Region

Select entities to define the exclusion region.

Select Deactivation Region

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.

Description Select (entity type)

Choose to either select Geometry or FEM to define the glue deactivation region.

Define Deactivated Entities

Select entities to define the entities that are to be un-glued.

Rigid Body (SOL 600 and SOL 700 only)

The input data form differs for 1D and 2D rigid bodies. One dimensional rigid surfaces are defined as beam elements, or as curves (which may optionally be meshed with beam elements prior to translation) and used in 2D problems. Two dimensional rigid surfaces must be defined as Quad/4 or Tri/3 elements, or as surfaces (which may optionally be meshed with Quad/4 or Tri/3 elements prior to translation) and are used in 3D problems. The elements will be translated as 4-node patches if meshed or as NURB surfaces if not meshed.

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Main Index

Input

Description

Flip Contact Side

Upon defining each rigid body, Patran displays normal vectors or tic marks. These should point inward to the rigid body. In other words, the side opposite the side with the vectors is the side of contact. Generally, the vector points away from the body in which it wants to contact. If it does not point inward, then use the modify option to turn this toggle ON. The direction of the inward normal will be reversed.

Symmetry Plane

This specifies that the surface or body is a symmetry plane. It is OFF by default.

Null Initial Motion

This toggle is enabled only for Velocity and Position type of Motion Control. If it is ON, the initial velocity, position, and angular velocity/rotation are set to zero in the CONTACT option regardless of their settings here (for increment zero).

Motion Control

Motion of rigid bodies can be controlled in a number of different ways: velocity, position (displacement), or forces/moments.

Velocity (vector)

For velocity controlled rigid bodies, define the X and Y velocity components for 2D problems or X, Y, and Z for 3D problems.

Angular Velocity (rad/time)

For velocity controlled rigid bodies, if the rigid body rotates, give its angular velocity in radians per time (seconds usually) about the center of rotation (global Z axis for 2D problems) or axis of rotation (for 3D problems).

Friction Coefficient (MU)

Coefficient of static friction for this contact body. For contact between two bodies with different friction coefficients the average value is used.

Rotation Reference Point

This is a point or node that defines the center of rotation of the rigid body. If left blank the rotation reference point will default to the origin.

Axis of Rotation

For 2D rigid surfaces in a 3D problem, aside from the rotation reference point, if you wish to define rotation you must also specify the axis in the form of a vector.

First Control Node

This is for Force or SPCD controlled rigid motion. It is the node to which the force or SPCD is applied. A separate LBC must be defined for the force, but the application node must also be specified here. If both force and moment are specified, they must use different control nodes even if they are coincident. If only 1 control node is specified the rigid body will not be allowed to rotate.

Second Control Node

This is for Moment controlled rigid motion. It is the node to which the moment is applied. A separate LBC must be defined for the moment, but the application node must also be specified here. It also acts as the rotation reference point. If both force and moment are specified, they must use different control nodes even if they are coincident.

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Note:

While importing the Nastran Input File, Patran adds a suffix to the names of contact bodies with unique IDs like: nName-DEFORM.1, name-DEFORM.2, name-RIGID.3 name* - indicates the name of the contact body being imported.

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Body Pair

This option defines the parameters for the LBC called Contact -- Body Pair, that consists of two contact bodies as a pair. The Input Data form contains two tabs: Geometric Contact Parameters and Physical Contact Parameters.

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Icon

Title

Description

Geometric Contact Input form for defining geometric parameters and contact options of Parameters the body pair. For details of the parameters, see: 3D - Body PairGeometric, 227

The contact options on this form are divided into two columns one for Body1/Slave and the other for Body2/Master. Select appropriate contact options from the given Rigid/Shell Elements and Edge contact options. Physical Contact Parameters

Input form for defining physical parameters of contact body pair. For details of the parameters, see: 3D - Body Pair- Physical, 229 For physical contact parameters of Thermal Analysis, see: Body Pair (p. 105) in the Patran Interface to MSC Nastran Thermal.

For display purposes and graphical identification of master/slave relationship, an arrow is drawn from the slave body toward the master body for each created body pair or when LBC markers are redrawn/displayed, similar to that shown here:

Slave Body

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Master Body

Chapter 2: Building A Model 269 Loads and Boundary Conditions

Planar Rigid Wall (SOL 700 only)

Object

Type

Analysis Type

Planar Rigid Wall

Nodal

Explicit Nonlinear

Two different planar rigid wall options exist: 1. Kinematic rigid wall without friction 2. Penalty method based rigid wall with friction These are seen as options at the top of the Input Data form. The user must select which wall will be used. Both wall’s position and orientation are defined by selecting a coordinate system which has its origin on the plane and the local z axis as the outward normal from the contact surface. This defines a WALL Bulk Data entry. There are only parameters associated with the penalty based planar rigid wall. Input Data

Description

Static Friction Coefficient

Static coefficient of friction.

Kinetic Friction Coefficient

Kinetic coefficient of friction.

Exponential Decay Coefficient

Exponential decay coefficient EXP.

Initial Rotation Field (SOL 700 only)

Object

Type

Analysis Type

Init. Rotation Field

Nodal

Explicit Nonlinear

Defines a velocity field of grid points consisting of a rotation and a traslation specification. Creates a TIC3 Bulk Data entry. Input Data

Main Index

Description

Trans Veloc(v1,v2,v3)

Defines the initial translational velocity values. These are in model length units per unit time.

Rot Veloc (w1,w2,w3)

Defines the initial rotational velocity values. These are in degrees per unit time.

Rotation Center

Defines a point at the center of rotation.

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Total Load Defines a pressure on 1D, 2D, or 3D elements, element faces, surfaces, or curves; or a force on element edges by entering the total desired load. Patran will distribute the load among affected nodes/elements. Total Load will automatically calculate individual Pressure Loads, or Forces as applicable. Alternatively, you can define a variable load using fields. Object

Type

Analysis Type

Dimension

Total Load

Element Uniform

Structural

1D/2D/ 3D

Total Load = Scale Factor * SQRT (X^2 + Y^2 +Z^2) When the model is exported to a Nastran input file, Total Load will create one or more entries for PLOAD1 (1D application region), PLOAD4 (2D or 3D application region), or FORCE (element edge application region) in the Bulk Data. For Total Load applied to element edges, Forcepernode = (Load/Total Length) * (element length/2). Input

Description

Current Load Case

The current load case. You can select it from the list of existing load cases.

Existing Sets

Displays existing load sets.

New Set Name

Type here the name of new total load set.

Target Element Type

Select the target element type: 1D, 2D, or 3D from the drop down option box.

Input Data...

Brings up the Input Data form, where you can define Load/BC Set Scale Factor and the loads according to element types.

Select Application Region Brings up the Select Application Region form, where you can specify application region for FEM or Geometric Entities. Total load can also be defined for region or element property.

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Crack (VCCT) This input data creates the VCCT keyword option. Multiple VCCT options are generated for each crack defined. This is valid for MSC Nastran 2010 or higher. VCCT is the Virtual Crack Closure Technique used for evaluating the energy release rates in crack growth analysis. Input Data

Type

Analysis

Description

Crack (VCCT)

Nodal

Structural 2D/3D

Defines a crack tip (2D) or a crack front (3D) and its corresponding parameters for crack growth analysis.

Definition of a crack has special input data. For crack in 2D solid and shell elements, the crack tip is defined by a single node, thus you simply select a single node as the Appication Region. If you select more than one node, all nodes will be referenced in the VCCT definition but will not be valid and MSC Nastran is likely to exit with an error or ignore all but the first or last node. For cracks in 3D elements, a crack front needs to be define, which is simply a list of nodes defining the crack front. The supported elements are lower- and higher-order 2-D solids and 3-D shells, lower- and higher-order 3-D hexahedral solids, and lower order 3-D tetrahedral solids. For 3-D solids, it is important that a regular mesh around the crack front is used. Multiple cracks can be defined and results are obtained for each crack separately. Each crack consists of a crack tip node in 2-D for shells and a list of nodes along the crack front for 3-D solids. Shell elements can be used for defining a 2-D style line crack and also be connected to the face of another shell or 3-D solid to form a 3-D style surface crack. These different cases are automatically identified. For crack propagation, there are two modes of growth: fatigue and direct. For fatigue style, the user specifies a load sequence time period. During the load sequence, the largest energy release rate and the corresponding estimated crack growth direction is recorded. At the end of the load sequence, the crack is grown using the specified method. For direct growth, the crack grows as soon as the calculated energy release rate is larger than the user-specified Gc. Note that Gc can be made a function of the accumulated crack growth length to model a crack growth resistance behavior. Crack opening or propagation may be modeled using two techniques. In the first method, the body in which the crack is located is remeshed based upon adaptive global remeshing criteria. This option is currently not available in MSC Nastran. In the second method, the uncracked area is represented by elements with double nodes and ties, RBE2 or RROD or by elements that are glued together via contact definitions. The Input Data form is specific to the parameters needed for defining crack growth and are listed in this table. The field name of the values/parameters written to the VCCT option as documented in the MSC Nastran Quick Reference Guide is indicated in parenthesis.

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Chapter 2: Building A Model 273 Loads and Boundary Conditions

Crack (VCCT) Input Data Property Crack Propagation Type:

Bulk Data (field) (ITYPE)

Description Can be set to No Crack or Direct. No Crack - means no crack propagation is initially performed. Direct - cracks grow when the energy release rate is larger than the user specified crack growth resistance (fracture toughness).

Crack Growth:

(IGROW)

This is the method of growing the crack. Released Glued will release MPC definitions (tying) and works with glued contact, RBE2/RROD, and tying type 100. This requires that the crack growth direction be known and is somewhat dictated by the mesh.

Growth Increment:

(INCM)

With fixed size the crack growth increment is directly given.

Direction Method:

(METHOD)

This is used for specifying the method for calculating the crack growth direction. Hoop Stress - The individual energy release modes are used for calculating the crack growth direction. This method is also called maximum principal stress criterion. See Marc Volume A, chapter 5, section on Fracture Mechanics for details on how this is calculated.

Crack Growth Increment Size:

(CGI)

This sets the fixed crack growth increment. It specifies the length the crack advances during growth. When re-meshing based growth is specified the given crack growth increment is directly used when extending the crack. For the option of releasing tied interface the crack is grown one element edge at the time, and as many edges as needed to reach the specified growth increment are released.

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Property Crack Growth Resistance Resistance Mode II Resistance Mode III

Bulk Data (field) (GC, GC-II, & GCIII)

Description This sets the crack growth resistance (often denoted fracture toughness) for the current crack. This value is used together with the total energy release rate growth criterion and provides the default for the separate modes: Mode I, Mode II, Mode III For each of the crack modes one can specify a separate crack growth resistance. The default is to use the value specified above. These values can be a function of accumulated crack growth (a displacement based non-spatial field), time, or temperature.

Accum C.G/Time/Temp Function

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TABCGI, TABGC, TABGC-II and TABGCIII

It shows list of non-spatial time or temperature dependent fields to select for Crack Growth increment size and resistance. This will write TABLEM1 if selected.

Chapter 2: Building A Model 275 Load Cases

2.10

Load Cases Load cases in Patran are used to group a series of load sets into one load environment for the model. Load cases are selected when defining an analysis job. The usage within MSC Nastran is similar. The individual load sets are translated into MSC Nastran load sets, and the load cases are used to create the SUBCASE commands in the Case Control Section. For information on how to define multiple static and/or transient load cases, see Load Cases Application (Ch. 5) in the Patran Reference Manual.

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2.11

Defining Contact Regions The MSC Nastran preference supports 3D slideline contact functionality introduced in MSC.Nastran Version 68. This capability allows the user to model contact between 2D and 3D structural regions or rigid bodies. This functionality can be accessed by using in the Loads/BCs Application in Patran. After selecting the Contact Object on the main form, the first step is to define the regions that may come into contact.

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Chapter 2: Building A Model 277 Defining Contact Regions

Pushing the Application Region button brings up the following form.

Entry

Main Index

Description

Geometry Filter

One or more curves, surface edges, or solid edges are defined for the Master and Slave application regions. The application region can only contain geometric entities. To model contact between FEM entities without associated geometry, curves must first be created from the nodes using the tools available in the Geometry application.

Active Region

Toggles the select box between Master and Slave regions. The Master and Slave application regions can be defined in either order.

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Entry

Description

Select Curves

Select the curve or edge.

Add

Adds the entities in the Select Curves databox to either the Master Region or Slave Region depending on the setting of the Active Region option menu.

Contact The second step is to define a set of properties of these contacting surfaces. This is done by pushing the Input Data button on the main Application form to bring up the following subordinate form.

Entry

Main Index

Description

Penetration Types

If the Penetration Type is One Sided, nodes in the Slave Region are not allowed to penetrate the segments of the Master Region. If Two Sided, in addition, nodes in the Master Region are not allowed to penetrate segments of the Slave Region. This is the PTYPE field on the BCONP entry.

Friction Coefficient (MU1)

Coefficient of static friction between the two surfaces. This is the MU1 field on the BFRIC entry.

Chapter 2: Building A Model 279 Defining Contact Regions

Entry

Main Index

Description

Stiffness in Stick (FSTIF)

FSTIF on the BFRIC entry and SFAC on the BCONP entry are penalty parameters in the contact formulation. The default values are usually adequate.

Slideline Width (W1)

Slideline Width is constant along the slideline and is used to determine the area for contact stress calculation. This is the Wi field on the BFRIC entry.

A Vector Pointing from Master to Slave Surface

A vector must be defined which lies in the contact plane and points from the Master region to the Slave region. This vector is used to define the coordinate system on the BCONP entry and the BLSEG entries for each region.

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2.12

Rotor Dynamics The MSC Nastran Preference supports steady state and transient rotor dynamics, introduced in MSC.Nastran 2004. This capability allows you to model structures with rotating parts, allowing for gyroscopic effects to be included. Rotor Dynamics are modelled using Rotor and Unbalance entities, created within the Rotor Dynamics... selection under the Tools menu:

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Rotor Dynamics Form The Rotor Dynamics form is accessed from the Rotor Dynamics... selection under the Tools menu. This form is used to create, modify, delete, or show Rotors, which define spin properties, including the axis of

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rotation, spin direction, damping factor, and speed.

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Entry Action

Description Create Modify Delete Show

Analysis

Steady State Transient

Object

Rotor Unbalance (Transient only)

Rotor Node List

A set of co-linear nodes that make up the rotor line model (spin axis). These are the grids in the MSC Nastran ROTORG Bulk Data entry.

Spin Direction Node 1 & Spin Direction Node 2

Two nodes defining the spin direction. These are the GRIDA and GRIDB fields in the MSC Nastran RSPINR and RSPINT Bulk Data entries. These nodes must be included in the “Rotor Node List” above.

Damping

Rotor structural damping factor (default 0.0). This is the GR field of the MSC Nastran RSPINR and RSPINT Bulk Data entries.

Spin Profile...

Spin Profile (Steady State) Spin History (Transient)

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Spin Profile Form For Steady State analyses, the Spin Profile form is used to define the relative spin rates.

Entry

Main Index

Description

Speeed Unit

The unit for the speed entries. RPM for revolutions per minute, or Cycles/Time for frequency. This value defines the SPDUNIT field of the MSC Nastran RSPINR Bulk Data entry, and are translated to either ‘RPM’ or ‘FREQ’.

Speed Values

List of relative spin rates. Entries must be in ascending or descending order. At least one entry required (no default). These values make up the SPEEDi fields of the MSC Nastran RSPINR Bulk Data entry.

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Spin History Form For Transient analyses, the Spin History form is used to define the spin rates.

Entry

Main Index

Description

Speed Unit

The unit for the speed entries. RPM for revolutions per minute, or Cycles/Time for frequency. This value defines the SPDUNIT field of the MSC Nastran RSPINT Bulk Data entry, and are translated to either ‘RPM’ or ‘FREQ’.

Speed Amplitude

A constant multiplier to be applied to the Time Dependent Field.

Time Dependent Field

A time dependent field that defines the spin rate as a function of time. This field, with the Speed Amplitude applied to it, will be translated into an MSC Nastran TABLED1 Bulk Data entry that is referenced by the RSPINT entry.

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Unbalance Form The Rotor Dynamics Unbalance form is used to create, modify, delete, or show Unbalances, which define unbalance loads for transient analyses in terms of cylindrical system with the rotor axis as the Z axis.

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Entry Action

Description Create Modify Delete Show

Main Index

Existing Transient Rotors

The unbalance is applied to a node, which must be included in a transient rotor. When a transient rotor is selected, the “Node” listbox is populated with nodes from that rotor’s axis. The unbalance node may then be selected from that list, assuring that it belongs to an existing transient rotor.

Node

This node defines the GRID field of the MSC Nastran UNBALNC Bulk Data entry.

Unbalance Properties...

Displays the Unbalance Properties form to define the remaining parameters for the MSC Nastran UNBALNC Bulk Data entry.

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Unbalance Properties Form The Unbalance Properties Form is used to define the remaining parameters for the Unbalance.

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Chapter 2: Building A Model 289 Rotor Dynamics

Entry

Description

Mass

Define the MASS, ROFFSET, and ZOFFSET fields of the MSC Nastran UNBALNC Bulk Data entry.

Radial Offest & Z Offset

For each of these values, either a constant real value may be specified, or a time dependent field my be selected from the list below. Time dependent fields are translated to TABLED1 entries, and referenced by integer ID values in the appropriate UNBALNC fields. Defaults are 1.0 for Radial Offset and 0.0 for Z Offset. There is no default for Mass.

Theta

Angular position, in degrees, of the mass in the unbalance coordinate system (default 0.0). This defines the THETA field of the MSC Nastran UNBALNC Bulk Data entry.

Time On & Time Off

The start and termination times for applying the unbalance load. The default start time is 0.0, while the default termination time is 999999.0. These values define the Ton and Toff fields of the MSC Nastran UNBALNC Bulk Data entry.

Correction

Correction flag to specify whether 1) the mass will be used to modify the total mass in the transient response calculations, 2) the effect of the rotor spin rate change will be included in the transient response calculation, or 3) both. Possible values are None, Mass, Speed, or Both (default None). This value defines the CFLAG field of the MSC Nastran UNBALNC Bulk Data entry.

Orientation Vector

Defines the coordinate system orientation relative to the ACID of the unbalance node (no default). This vector defines the X1, X2, and X3 fields of the MSC Nastran UNBALNC Bulk Data entry.

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Chapter 3: Running an Analysis Patran Interface to MSC Nastran Preference Guide

3

Main Index

Running an Analysis



Review of the Analysis Form



Translation Parameters



Solution Types



Direct Text Input



Solution Parameters



Select Superelements



Subcases



Subcase Parameters



Output Requests



Select Superelements

409



Select Explicit MPCs...

508



Non-Structural Mass Properties



Select NSM Properties...



Subcase Select



Restart Parameters



Optimize



Toptomize



Interactive Analysis

292

298

305 310 312 409

411 414

478

515 531

537 539 550

514

509

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Patran Interface to MSC Nastran Preference Guide Review of the Analysis Form

3.1

Review of the Analysis Form The Analysis form appears when the Analysis toggle, located on the Patran mainform, is chosen. To run an analysis, or to create a NASTRAN input file, select Analyze as the Action on the Analysis form. Other forms brought up by the Analysis form are used to define translation parameters, solution type, solution parameters, output requests, and the load cases. These forms are described on the following pages. For further information see The Analysis Form (p. 8) in the Patran Reference Manual.

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Chapter 3: Running an Analysis 293 Review of the Analysis Form

Analysis Form This form appears when the Analysis toggle is chosen on the main menu. When preparing for an analysis run, select Analyze as the Action.

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Entry

Main Index

Description

Action

Actions can be set to: Analyze or Optimize or Toptomize Access Results Read Input File Delete Monitor (if Patran Analysis Manager is installed). Abort (if Patran Analysis Manager is installed).

Code & Type

Indicates the selected Analysis Code and Analysis Type, as defined in the Preferences>Analysis (p. 427) in the Patran Reference Manual.

Available Jobs

List of already existing jobs. If one of these jobs is selected, the name will appear in the Job Name list box and all parameters for this job will be retrieved from the database. An existing job can be submitted again by simply selecting it and pushing Apply. It is often convenient to select an existing job, modify a few parameters and push Apply to submit the new job.

Job Name

Name of job. This name will be used as the base file name for all resulting MSC Nastran files and message files.

Job Description (Title), SUBTITLE, & LABEL

This text is used to generate the TITLE entry in the MSC Nastran executive control section.

Translation Parameters...

Displays the Translation Parameters form to specify parameters not directly related to the solution. These are primarily used by the Application Preferences during the forward translation.

Solution Type...

Displays the Solution Types form to select the desired type of analysis to run.

Direct Text Input...

Opens the Direct Text Input form which allows you to directly enter data for the BULK DATA, Case Control, Executive Control and File Management sections of the NASTRAN input file.

Select Superelements

Opens the Select Superelements form which allows you to select the superelements active for the specified job.

Subcases...

Displays the Subcases form to select a list of load cases to be included in this analysis run. The list of selected load cases is order dependent.

Subcase Select...

Displays the Subcase Select form to select a sequence of subcases associated with an analysis job.

Analysis Manager...

Gives access to the Analysis Manager for submitting, monitoring, aborting and generally managing a Nastran job. This button will not appear if the Analysis Manager is not installed or licensed.

Chapter 3: Running an Analysis 295 Review of the Analysis Form

The following table outlines the selections for the Analyze action. Object Entire Model

Method Full Run Check Run Analysis Deck Model Only Load SimXpert

Selected Group

Full Run Check Run Analysis Deck Model Only Load SimXpert

Existing Deck

Full Run Load SimXpert

Restart

Full Run Check Run Analysis Deck

Interactive

Full Run

The Object indicates which part of the model is to be analyzed. There are four choices: Entire Model, Current Group, Existing Deck, and Restart. • Entire Model is the selected Object if the whole model is to be analyzed. • Selected Group is for specifying the group that contains the model that is to be analyzed. Select

the button Select Group..., under Existing Groups select the desired group, then select Cancel. The name of the selected group will appear in the Analysis form under Group:. For more information see The Group Menu (p. 248) in the Patran Reference Manual. • Existing Deck is selected if you wish to simply submit an existing input file to MSC Nastran.

The jobname appearing in the Job Name listbox is appended with the suffix “.bdf” to form the input filename. This file must reside in the current directory. You may also use Existing Deck to directly edit the MSC Nastran Bulk Data file.

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• Restart is selected if you wish to restart an analysis. Currently, restarts are only supported for

the Linear Static (101), Nonlinear Static (106), and Normal Modes (103) solution types. The Restart Parameters, 531 form allows you to specify where to resume the analysis. • Interactive analysis utilizes the Patran Preference for MSC Nastran capability for performing

visual interactive modal frequency response analysis. The process begins by creating a modal analysis solution using MSC Nastran. The interactive modal frequency response analysis is then performed using Patran Analysis: Analyze / Interactive / Full Run. The chain that is followed is 1) using Select Nastran. MASTER... select a .DBALL file, 2) using Create Loading... specify the loading (for example, Acoustic, Force), 3) using Output Requests... specify the desired output, and 4) using View Results... view the results. The Method indicates how far the translation is to be taken.The methods are listed below: • Full Run is the selected type if an Analysis Deck translation is done, and the resulting input file

is submitted to MSC Nastran for complete analysis. • Check Run is the selected type if an Analysis Deck translation is done, and the resulting input

file is submitted to MSC Nastran for a check run only. • Analysis Deck is the selected type if the Model Deck translation is done, plus all load case,

analysis type and analysis parameter data are translated. A complete input file, ready for MSC Nastran should be generated. • Model Only is the selected type if a Bulk Data file is created that contains only the model data

including node, element, coordinate frame, element property, material property, and loads and boundary condition data. The translation stops at that point. • Load SimXpert will launch SimXpert and automatically transfer the finite element model. The

environment variable MSC_SX_HOME must be set to a valid local installation directory of SimXpert for this capability to be available.

Overview of Analysis Job Definition and Submittal To submit a single load case, linear static analysis job to MSC Nastran it is necessary only to click the Apply button on the main Analysis form. Appropriate defaults and selections will be made automatically. Other solution types or multiple load cases will require access to one or more lower-level forms. Several different analysis examples are considered below. To perform a multiple load case, linear static analysis, it is necessary only to open the Subcase Select form. Subcases with the same names as the user-defined load case names and with appropriate defaults can be selected for inclusion in the job. If a change to one or more parameters for a subcase is desired (e.g., to change an output request), the Subcases... form must be accessed. Then it is simple to select a subcase and bring up the appropriate form (e.g., Output Requests) to make changes. For other analysis types (e.g., Normal Modes), the first step is to bring up the Solution Type form and make the appropriate selection. A lower-level Solution Parameters form can be accessed from the Solution Type form to change parameters that affect the overall analysis. Just as for the linear static case, subcases are automatically created for each defined load case. These can be selected on the Subcase Select form or modified on the Subcases form.

Main Index

Chapter 3: Running an Analysis 297 Review of the Analysis Form

In the Patran MSC Nastran Interface, a subcase can be thought of as a Patran load case with some additional parameters (e.g., Output Requests) associated with it. This association is further strengthened since the default subcases are created for each load case and have the same name as their associated load case. In the rest of this document, the terms load case and subcase will generally be used interchangeably. When a specific form is referenced, Load case and Subcase will be capitalized.

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3.2

Translation Parameters Translation parameters define output file formats, numerical tolerances, processing options, numbering offsets, and external include files.

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Chapter 3: Running an Analysis 299 Translation Parameters

Tolerances

• Division - prevents divide by zero errors. • Numerical - determines if two real values are equal. • Writing determines if a value is approximately zero when generating a

Bulk Data entry field. Bulk Data Format

• Sorted Bulk Data - Sorts Bulk Data entries alphabetically. • "Card Format - Determines whether real numbers are written to a standard

(8 character) NASTRAN field or to a double (16 character) NASTRAN field. If Either is set, the precision necessary will determine whether an 8 or 16 character field is used. The following preference can be included in the settings.pcl file to set the default: pref_env_set_string("NastranCardFormat", value), where value is either "Small," "Large," or "Either." See The settings.pcl File (p. 53) in the Patran Installation and Operations Guide for more details. • Write Stored Precision - When ON it writes all data as double precision if

the data double precision information. • Precision Control Options - Specifies where to round off a grid point

coordinate, material, property, or other entity value before its written out to the bdf file. For example if this value is specified as 2 the number 1.3398 will be written out as 1.34. This option has been implemented for entities: Grids, Coordinate Frames, MPCs, LBCs, Materials and Properties. Node Coordinates

Defines which coordinate frame is used when generating the grid coordinates.

Coordinate Frame Coordinates

Defines which coordinate frame is used when generating the grid coordinates. This can be set to reference frame, analysis frame, or global. This should not affect the analysis. It only changes the method used in the grid creation. This determines which coordinate frame is referenced in the CP field of the GRID entry.

MSC Nastran Version

Specifies the version of MSC Nastran. The version specified here is used for two purposes: to create the full name of the ALTER file to be used, and to determine which Solution Sequence to use. Use only whole numbers and letters; for example, 66a, 67 and 68; 67.5 is the same as 67. This version number can be overridden by setting the environment variable “NASTRAN_VERSION”.

Number of Tasks

Represents the number of processors to be used to run an analysis. It is assumed that the environment is configured for distributed parallel processing.

Write Properties on Element Entries

Specifies that properties will be written to the element entries for all elements where it is allowed in MSC Nastran.

Write Continuation Markers

This option is OFF by default. This option can be turned ON to write continuation markers for Bulk Data entries.

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Write Global Ply IDs

When ON, attempts to keep the Global Ply IDs consistent between MSC Nastran and Patran.

Convert CBARs to CBEAMs

Converts all CBARs to CBEAMS

Write PARTSuperelement

This is ON by default and if ON and superelements are selected (see Select Superelements, 409 then BEGIN BULK SUPER = id sections are written in to the input file for each selected superelement. If OFF and superelements are selected, then SESET entries are written instead to define the superelements.

Geometry Check

Checks the element shapes to make sure they are valid. You can set different warning levels from None to Fatal depending on how crucial the element shapes are to your model.

Use Iterative Solver

Activates the iterative solver for analysis. The analysis manger does not support this option and must be disabled when using this option.

Ext. Superelement Spec...

Subform used for defining superelement specifications.

Numbering Options...

Subform used to indicate offsets for all IDS to be automatically assigned during translation.

Bulk Data Include File...

Prompts you for the filename of the include file.

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Chapter 3: Running an Analysis 301 Translation Parameters

External Superelement Specifications With this form you can define the options for the External Superelements Bulk Data entry. Please see the MSC Nastran Quick Reference Guide for more information about External Superelements.

Entry Method

Description The available methods are: NONE – No EXTSEOUT entry created. DMIGPCH – Requires an EXTID MATRIXDB DMIGDB DMIGOP2

ASM Bulk & EXT Bulk

ASM BULK and EXT BULK require the EXTID method.

Numbering Options This form is activated by the Numbering Options button on the Translation Parameters form. It allows the user to indicate offsets for all IDS to be automatically assigned during translation. For example, if the

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Patran Interface to MSC Nastran Preference Guide Translation Parameters

user types 100 into the Element Properties Offset box, the numbering of element properties in the resulting NASTRAN input file will begin at 101.

Entry Begin Contin. Marker:

Main Index

Description The Begin. Contin. Marker box allows the user to specify the continuation of the mnemonic format used on multiple line, Bulk Data entries.

Chapter 3: Running an Analysis 303 Translation Parameters

Entry IDs Encoded in Names:

Description IDs Encoded in Names allows the user to activate recognition of IDs encoded into the name of any named entity, such as a material. Number Only will recognize and use an ID if, and only if, the name of the entity is an actual number like “105.” This option is ON by default. Beginning Number will recognize an ID if the number begins the name, such as “52_shell_property.” This option is OFF by default. Trailing Number will recognize an ID if it trails the name, such as “shell_property_52.” This option is OFF by default. Encoded Syntax will recognize an ID if it directly follows the first occurrence of the specified syntax. For example, with this option activated and the specified syntax set to “.”, the ID assigned to a material given the name “Steel_1027.32” would be 32.

Note that both the Patran Neutral file reader and the Patran MSC Nastran input file reader preserve the IDs of named entities with a “.” syntax, so that a NASTRAN PSHELL record of ID 12 will be assigned the name “PSHELL.12.” This last option allows great continuity between input model data and output model data. This option is ON by default and the default Syntax Marker is “.”.

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Select File

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Chapter 3: Running an Analysis 305 Solution Types

3.3

Solution Types The Solution Type form defines the type of analysis and Solution Parameters. Your choice for the Solution Type will in turn affect additional forms you complete for Solution Parameters, 312, Subcase Parameters, 414, and Output Requests, 478. See Table 3-1. To set the Solution Type: Click on the Analysis Application button. On the Analysis Application form, click Solution Type... and select the Solution Type from the list of available Solution Types.

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Patran Interface to MSC Nastran Preference Guide Solution Types

Solution Type

Main Index

Description

• Linear Static

Selects Solution Sequence (SOL) 101, 114, 1, or 47 depending on the selected Solution Parameters. You may select one or more subcases in SOLs 1 and 101.

• Nonlinear Static

Selects Solution Sequence 66 or 106, depending on the version of MSC Nastran. Version 66 and below yields SOL 66, and Version 67 and above yields SOL 106. You may select one or more subcases.

• Normal Modes

Selects Solution Sequence 103, 115, 3, or 48 depending on the Solution Parameters. You may select only one subcase.

• Buckling

Selects Solution Sequence 105, 77, or 5 depending on the selected Solution Parameters. Only one subcase may be selected that defines the static preload. The buckling subcase is automatically generated. The output requests for this Solution Type are applied to the static preload subcase. The default output requests for the buckling subcase are displacements and constraint forces.

• Complex Eigenvalue

Selects Solution Sequence 107, 110, 28, or 29 depending on the selected Solution Parameters. You may select only one subcase.

• Frequency Response

Selects Solution Sequence 108, 111, 118, 26, or 30 depending on the selected Solution Parameters. You may specify only one subcase for Solution Sequences 118, 26, or 30. For Solution Sequences 108 or 111, multiple subcases may be selected.

• Transient Response

Selects Solution Sequence 109, 112, 27, or 31 depending on the selected Solution Parameters. You may specify only one subcase for Solution Sequences 27 or 31. For Solutions Sequences 109 or 112, multiple subcases may be selected.

• Nonlinear Transient

Selects Solution Sequence 99 or 129, depending on the MSC Nastran Version. Version 66 and below yields SOL 99; Version 67 and above yields SOL 129. You may select only one subcase.

• Implicit Nonlinear

Selects Solution Sequence 400 or 600 (depending on “SOL400RUN* toggle).

• DDAM Solution

Selects Solution Sequence 187, Dynamic Design Analysis Method (DDAM).

• Explicit Nonlinear

Selects Solution Sequence 700.

Chapter 3: Running an Analysis 307 Solution Types

Solution Type

Description

Select ASET/QSET...

• Select existing Degree of Freedom Lists for use in making an ASET or

a QSET in the input file. • The ASET toggle creates a user selected unreferenced SPOINTS in the

ASET of input file. • The QSET toggle creates a user selected number of unreferenced

SPOINTS in the QSET of the input file. Solution Parameters...

Main Index

Brings up a solution-type-dependent subordinate form that allows you to specify parameters which apply to the complete solution.

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Patran Interface to MSC Nastran Preference Guide Solution Types

Solution Type Linear Static

Nonlinear Static Normal Modes

Buckling

Complex Eigenvalue

Frequency Response

Transient Response

Nonlinear Transient Implicit Nonlinear

Formulation

MSC Nastran Version

Solution Parameter Settings

Off

--

--

1

Off

On

--

--

47

On

Off

--

--

101

On

On

--

--

114

--

--

--

66 or Below

66

--

--

--

67 or Above

106

Off

Off

--

--

3

Off

On

--

--

48

On

Off

--

--

103

On

On

--

--

115

Off

Off

--

--

5

On

On

--

--

77

On

Off

--

--

105

Off

--

Direct

--

28

Off

--

Modal

--

29

On

--

Direct

--

107

On

--

Modal

--

110

Off

--

Direct

--

26

Off

--

Modal

--

30

On

Off

Direct

--

108

On

--

Modal

--

111

On

On

Direct

--

118

Off

--

Direct

--

27

Off

--

Modal

--

31

On

--

Direct

--

109

On

--

Modal

--

112

--

--

--

66 or Below

99

--

--

--

67 or Above

129

Database Run

Cyclic Symmetry

Off

400 600

Main Index

Chapter 3: Running an Analysis 309 Solution Types

MSC Nastran Version

Solution Parameter Settings

DDAM Solution

2004

187

Explicit Nonlinear

2005

700

Solution Type

Main Index

Database Run

Cyclic Symmetry

Formulation

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Patran Interface to MSC Nastran Preference Guide Direct Text Input

3.4

Direct Text Input This form is used to directly enter entries in the File Management, Executive Control, Case Control, and BULK DATA sections of the NASTRAN input file. The input file reader also creates these entries for any unsupported entries in the input file. If the data is entered by the user the Write to Input Deck toggle default is ON. If the data comes from the input file reader the default for the Input Deck toggle is OFF. These entries may be reviewed and edited by the user. If they should be written to any input files subsequently created by the interface, the appropriate Write to Input Deck toggle should be set to ON. Text entered into the Case Control section is written to the input file before the first subcase. The Direct Text Input option on the Subcases form should be used to directly enter text within a subcase definition. MSC Nastran Input File Import When an MSC Nastran input deck is imported, data in the MSC Nastran input deck that is not recognized by Patran, including comments are placed in the reject file. These rejected cards are also placed into the Direct Text Input (DTI) text boxes. If you turn ON the ability to write DTI into the various portions of the MSC Nastran input deck, the rejected cards will be placed back into the input deck when it is written out again. Note that decks with large amounts of rejected cards and comments may place an unacceptable amount of data in these text boxes. If this is the case, you can limit the amount of data by setting the environment variable:

Main Index

Chapter 3: Running an Analysis 311 Direct Text Input

Entry

Main Index

Description

Bulk Data Section

Switches to determine which data section the MSC Nastran input would be sent.

OK

Saves the current setting and data for the four sections and closes the form.

Clear

Clears the current form.

Reset

Resets the form back to the data values it had at the last OK.

Cancel

Resets all four forms back to its previous value and closes the form.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

3.5

Solution Parameters Linear Static This subordinate form appears when the Dynamic Reduction button is selected on the Normal Modes, Complex Eigenvalue, Frequency Response, or Transient Response Solution Parameters forms. Use this form to create the DYNRED Bulk Data entry. Note that access to this form is only available when the Nastran version is less than 2005. Dynamic reduction parameters are not necessary for later versions of Nastran.

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Chapter 3: Running an Analysis 313 Solution Parameters

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Database Run

Indicates whether a Structured Solution Sequence (SOL 101 or 114) is to be used or a Rigid Format (SOL 1 or 47). If selected, a Structured Solution Sequence is selected.

Cyclic Symmetry

Indicates that this model is a sector of a cyclically repeating part (SOL 114 or 47).

Automatic Constraints

Indicates that an AUTOSPC entry is requested, so that MSC Nastran will constrain model singularities.

Inertia Relief

Indicates that the inertia relief flags are to be set by including the PARAM, INREL,1 command. This flag can only be chosen if Database Run is selected and Cyclic Symmetry is disabled. If inertia relief is selected, a node-ID for weight generation must be selected. A PARAM, GRDPNT and a SUPORT command will be written to the input file using the same node-ID selected for weight generation. The SUPORT entry will specify all 6 degrees of freedom.

Alternate Reduction

Indicates that an alternate method of performing the static condensation is desired. The PARAM, ALTRED,YES command is included if selected and if Database Run is also selected

SOL 600 Run

Indicates a SOL 600 run.

Contact Parameters

Same as the contact parameters available for the Implicit Nonlinear solution type. Only used with linear contact capability. See Contact Parameters Subform, 350.

Shell Normal

Indicates that MSC Nastran will define grid point normals for a Faceted Shell Surface based on the Tolerance Angle. This data appears on a PARAM, SNORM entry.

Tolerance Angle Mass Calculation

Defines how the mass matrix is to be treated within MSC Nastran. This controls the setting of the COUPMASS parameter. This parameter can be set to either Coupled or Lumped. If set to Coupled, COUPMASS will be set to +1, otherwise, it will be set to -1.

Data Deck Echo

Indicates how the data file entry images are to be printed in the MSC Nastran print file. This controls the setting used for the ECHO Case Control command. This parameter can have one of three settings: Sorted, Unsorted, or None.

Plate Rz Stiffness Factor

Defines the in plane stiffness factor to be applied to shell elements. This defines the K6ROT parameter. This is an alternate method to suppress the grid point singularities and is intended primarily for geometric nonlinear analysis.

Maximum Printed Lines

Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.

Maximum Run Time

Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

Node ID for Wt. Gener.

Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

Main Index

Chapter 3: Running an Analysis 315 Solution Parameters

Default Initial Temperature

Defines the Default Initial Temperature: TEMPD value for subcase entry TEMP(INITIAL)

Default Load Temperature Defines the Default Load Temperature: Sets the TEMPD value for the subcase entry TEMP(LOAD) subcase entry. Rigid Element Type:

The Rigid element type optionmenu presents three different types of rigid elements, corresponding to the three possible values for the Nastran RIGID= case control. They are:

• LINEAR: Selects linear rigid elements, which are the rigid elements that

have been available in MSC Nastran since its inception. • LAGR: Selects the new Lagrange rigid elements with the Lagrange

multiplier method. • LGELIM: Selects the new Lagrange rigid elements with the Lagrange

elimination method. See the Nastran quick reference guide for more details. Fatigue Parameters

Parameters on this form are used to run an MSC Nastran Embedded Fatigue analysis. See Fatigue Parameters Subform, 370.

Results Output Format

On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.

The table outlines the Database Run and Cyclic Symmetry selections, and the SOL types that will be used. Database Run

Cyclic Symmetry

SOL

On

Off

101

On

On

114

Off

Off

1

Off

On

47

Nonlinear Static This subordinate form appears when the Solution Parameters button is selected on the Solution Type form, when Nonlinear Static is selected. If the MSC Nastran version specified is Version 66 or lower, then Solution Sequence (SOL) 66 will be employed. However, if the MSC Nastran version specified is version 67 or higher, then Solution Sequence 106 will be employed except as described below. For more

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information about specification of the MSC Nastran version number, see the Translation Parameters, 298 form.

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Chapter 3: Running an Analysis 317 Solution Parameters

Entry

Main Index

Description

Automatic Constraints

Indicates that an AUTOSPC entry is requested. MSC Nastran will automatically constrain model singularities.

Large Displacements

Indicates that displacements, which can cause a difference in the formulation of the stiffness matrix, may be encountered. Therefore, the stiffness matrix may need to be periodically recomputed based on the displaced shape.

Follower Forces

Indicates, as the part deflects, that the applied forces will remain aligned with the deformed part rather than maintaining their global orientation. This can only be selected if Large Displacements is also selected.

Solution Sequence

The default solution sequence for Nonlinear Static is 106, but can be changed to any one of the following if desired: 400, 600, 700. Only features of 106 are used in any case. For specific features particular to 600 or 700, please use the Implicit Nonlinear type or set the Analysis Type to Explicit Nonlinear, respectively.

Mass Calculation

Defines how the mass matrix is to be treated within MSC Nastran. This controls the setting of the COUPMASS parameter. This parameter can be set to either Coupled or Lumped. If set to Coupled, COUPMASS will be set to +1, otherwise, it will be set to -1.

Data Deck Echo

Indicates how the data file entry images are to be printed in the MSC Nastran print file. This controls the setting used for the ECHO Case Control command. This parameter can have one of three settings: Sorted, Unsorted, or None.

Plate Rz Stiffness Factor

Defines the in plane stiffness factor to be applied to shell elements. This defines the K6ROT parameter. This is an alternate method to suppress the grid point singularities and is intended primarily for geometric nonlinear analysis.

Maximum Printed Lines

Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.

Maximum Run Time

Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

Node ID for Wt. Gener.

Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

Results Output Format

On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.

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The following table outlines the selections for Large Displacements and Follower Forces, and the altered LGDISP parameter setting for each.

Main Index

Large Displacements

Follower Forces

LGDISP

Off

On

-1

On

On

1

On

Off

2

Chapter 3: Running an Analysis 319 Solution Parameters

Normal Modes This subordinate form appears when Solution Parameters is selected on the Solution Type form when Normal Modes is selected. Use this form to generate a SOL 103, 115, 3, or 48 input file, depending on the Database Run and Cyclic Symmetry parameters below.

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Entry

Description See Real Eigenvalue Extraction, 322. Not shown unless Cyclic Symmetry is on. If the version is Version Š 68 and the solution sequence is SOL 103, then these controls are selectable on the Normal Modes Subcase Parameters, 421 form.

The following table outlines the selections for Database Run and Cyclic Symmetry, and the altered SOL type for each. Indicates whether a Structured Solution Sequence (SOLs 103 or 115) is to be used, or a Rigid Format (SOL 3 or 48). If Database Run is selected, a Structured Solution Sequence will be selected. Database Run

Cyclic Symmetry

SOL

On

Off

103

On

On

115

Off

Off

3

Off

On

48

This is a list of data input, available for defining the Normal Modes Solution Parameters, that were not shown on the previous page. Parameter Name Cyclic Symmetry

Indicates that this model is a sector of a cyclically repeating part (SOL 115 or 48).

Automatic Constraints

Indicates that an AUTOSPC entry is requested, so that MSC Nastran will constrain model singularities.

SOL 600 Run

Select this to perform a SOL 600 analysis.

Residual Vector

The Residual Vector Computation toggle writes RESVEC=YES or RESVEC=NO to the Case Control. This calculates residual vectors due to applied loads. The default is to calculate residual vectors.

Computation Shell Normal Tolerance Angle

Main Index

Description

Indicates that MSC Nastran will define grid point normals for a Faceted Shell Surface based on the Tolerance Angle. This data appears on a PARAM, SNORM entry.

Mass Calculation

Defines how the mass matrix is to be treated within MSC Nastran. This controls the setting of the COUPMASS parameter. This parameter can be set to either Coupled or Lumped. If set to Coupled, COUPMASS will be set to +1, otherwise, it will be set to -1.

Data Deck Echo

Indicates how the data file entry images are to be printed in the MSC Nastran print file. This controls the setting used for the ECHO Case Control command. This parameter can have one of three settings: Sorted, Unsorted, or None.

Chapter 3: Running an Analysis 321 Solution Parameters

Parameter Name Plate Rz Stiffness Factor

Defines the in plane stiffness factor to be applied to shell elements. This defines the K6ROT parameter. This is an alternate method to suppress the grid point singularities and is intended primarily for geometric nonlinear analysis.

Maximum Printed Lines

Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.

Maximum Run Time

Limits the amount of CPU time expressed in CPU minutes that can be used by this run (used to prevent runaway jobs). This defines the setting of the TIME Executive Control statement.

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

Node ID for Wt. Gener.

Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

Default Initial Temperature

Specify the initial temperature.

Rigid Element Type

There are three ways to define a rigid element. They are 1) Linear, 2) Lagrangian, or 3) Lgelim.

Max p-Adaptive Cycles

Specify the maximum number of p-Adaptive cycles.

• Dynamic Reduction

Brings up the Dynamic Reduction Parameters form for defining the dynamic reduction controls.

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

Node ID for Wt. Gener.

Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

Default Initial Temperature

Specify the initial temperature.

Rigid Element Type

There are three ways to define a rigid element. They are 1) Linear, 2) Lagrangian, or 3) Lgelim.

Max p-Adaptive Cycles

Specify the maximum number of p-Adaptive cycles.

• Dynamic Reduction

Main Index

Description

Brings up the Dynamic Reduction Parameters form for defining the dynamic reduction controls.

Fatigue Parameters

Parameters on this form are used to run an MSC Nastran Embedded Fatigue analysis. See Fatigue Parameters Subform, 370.

Results Output Format

On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Real Eigenvalue Extraction

This subordinate form appears when the Eigenvalue Extraction button is selected on the Normal Modes, Frequency Response, or Transient Response Solution Parameters forms. It also appears when the Real Eigenvalue Extraction button is selected on the Complex Eigenvalue Solution Parameter form. Use this form to create either EIGR or EIGRL Bulk Data entries.

Main Index

Chapter 3: Running an Analysis 323 Solution Parameters

Parameter Name

Main Index

Description

Extraction Method

Defines the method to use to extract the real eigenvalues. This parameter can be set to any one of the following: Lanczos, Automatic Givens, Automatic Householder, Modified Givens, Modified Householder, Givens, Householder, Enhanced Inverse Power, or Inverse Power. If this selection is set to Lanczos, an EIGRL Bulk Data entry should be created. Otherwise, this defines the setting of the METHOD field on the EIGR Bulk Data entry.

Frequency Range of Interest

Defines the lower and upper limits to the range of frequencies to be examined. These are the F1 and F2 fields on the EIGR Bulk Data entry or the V1 and V2 fields on the EIGRL Bulk Data entry.

Estimated Number of Roots=

Indicates an estimate of the number of eigenvalues to be located. This parameter can only be specified if Extraction Method is set to Enhanced Inverse Power or Inverse Power. This is the NE field on the EIGR Bulk Data entry.

Number of Desired Roots

Indicates the limit to how many eigenvalues to be computed. This is the ND field on the EIGR or EIGRL Bulk Data entries.

Diagnostic Output Level

Defines the level of desired output. This can take any integer value between 0 and 3. This parameter can only be specified if Extraction Method is set to Lanczos. This is the MSGLVL field on the EIGRL Bulk Data entry.

Normalization Method

Indicates what type of eigenvalue normalization is to be done. This parameter can take one of three settings: Mass, Maximum, or Point. This parameter cannot be specified if Extraction Method is set to Lanczos. Defines the setting of the NORM field on the EIGR Bulk Data entry.

Normalization Point

Defines the point to be used in the normalization. This can only be selected if Normalization Method is set to Point. This parameter cannot be specified if Extraction Method is set to Lanczos. This is the G field on the EIGR Bulk Data entry.

Normalization Component

Defines the degree-of-freedom component at the Normalization Point to be used. This can only be selected if Normalization Method is set to Point. This parameter cannot be specified if Extraction Method is set to Lanczos. This is the C field on the EIGR Bulk Data entry.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Dynamic Reduction Parameters

This subordinate form appears when the Dynamic Reduction button is selected on the Normal Modes, Complex Eigenvalue, Frequency Response, or Transient Response Solution Parameters forms. Use this form to create the DYNRED Bulk Data entry.

Parameter Name

Main Index

Description

Perform Dynamic Reduction

A flag that indicates whether or not any dynamic reduction is desired.

Highest Frequency of Interest=

Indicates the maximum frequency to be considered when performing dynamic reduction. This parameter can only be selected if Perform Dynamic Reduction is set to ON. This is the FMAX field.

Method

Indicates which method is to be used in selecting coordinates. This parameter can be set to either Automatic or Manual. This parameter can only be selected if Perform Dynamic Reduction is set to ON. This determines if the program will automatically select the number of generalized coordinates.

Chapter 3: Running an Analysis 325 Solution Parameters

Parameter Name

Main Index

Description

Number of Generalized Coordinates=

Defines the number of generalized coordinates to be included in the dynamic reduction. This parameter can only be selected if Perform Dynamic Reduction is set to ON, and Method of Coordinate Selection is set to Manual. This is the NQDES field.

Number of Needed Scalar Points=

Indicates the number of scalar points that must be retained in this dynamic reduction. This parameter can only be selected if Perform Dynamic Reduction is set to ON and Method of Coordinate Selection is set to Manual. The Application Preference will automatically create this many SPOINTs, and place them in the a-set and the q-set.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Buckling This subordinate form appears when Solution Parameters is selected on the Solution Type form when Buckling is selected. Use this form to generate a SOL 105, 77, or 5 input file, depending on the setting of the Database Run and Cyclic Symmetry parameters.

Main Index

Chapter 3: Running an Analysis 327 Solution Parameters

The following table outlines the selections for Database Run and Cyclic Symmetry, and the altered SOL type for each. Database Run

Cyclic Symmetry

SOL

On

Off

105

On

On

77

Off

Off

5

This is a list of data input available for defining the Buckling Solution Parameters that were not shown on the previous page. Parameter Name

Main Index

Description

Database Run

Indicates whether a Structured Solution Sequence (SOL 105) is to be used or a Rigid Format or unstructured Solution Sequence (SOL 5 or 77). If Database Run is selected, a Structured Solution Sequence will be selected.

Cyclic Symmetry

Indicates that this model is a sector of a cyclically repeating part.

Automatic Constraints

Indicates that an AUTOSPC entry is requested, so that MSC Nastran will automatically constrain model singularities.

Eigenvalue Extraction

See Real Eigenvalue Extraction, 322.

Mass Calculation

Defines how the mass matrix is to be treated within MSC Nastran. This controls the setting of the COUPMASS parameter. This parameter can be set to either Coupled or Lumped. If set to Coupled, COUPMASS will be set to +1, otherwise, it will be set to -1.

Data Deck Echo

Indicates how the data file entry images are to be printed in the MSC Nastran print file. This controls the setting used for the ECHO Case Control command. This parameter can have one of three settings: Sorted, Unsorted, or None.

Plate Rz Stiffness Factor

Defines the in plane stiffness factor to be applied to shell elements. This defines the K6ROT parameter. This is an alternate method to suppress the grid point singularities and is intended primarily for geometric nonlinear analysis.

Maximum Printed Lines

Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.

Maximum Run Time

Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Parameter Name Node ID for Wt. Gener.

Description Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

• Eigenvalue Extraction Brings up the Buckling Eigenvalue Extraction form for defining the

eigenvalue extraction controls. Results Output Format

Main Index

On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.

Chapter 3: Running an Analysis 329 Solution Parameters

Buckling Eigenvalue Extraction

This subordinate form appears when the Eigenvalue Extraction button is selected on the Buckling Solution Parameters form. Use this form to create either EIGB or EIGRL Bulk Data entries, depending on the selected extraction method.

Main Index

330

Patran Interface to MSC Nastran Preference Guide Solution Parameters

This is a list of data input, available for defining the Buckling Eigenvalue Extraction. Parameter Name

Main Index

Description

Extraction Method

Defines the method to use to extract the buckling eigenvalues. This parameter can be set to any one of the following: Lanczos, Enhanced Inverse Power, or Inverse Power. If Lanczos is selected, an EIGRL entry will be created. If Inverse Power or Enhanced Inverse Power are selected, and EIGB entry will be created with the METHOD field set to either INV or SINV specified, respectively.

Eigenvalue Range of Interest

Defines the lower and upper limits to the range of eigenvalues to be examined. These are the L1 and L2 fields on the EIGB entry or the V1 and V2 fields on the EIGRL entry.

Estimated Number of Roots=

Indicates an estimate of the number of eigenvalues to be located. This parameter can only be specified if Extraction Method is set to Inverse Power. This is the NEP field on the EIGB entry.

Number of Desired Roots=

Indicates the limit to how many eigenvalues to be computed. This value can only be selected if Extraction Methods set to Lanczos. This is the NP field on the EIGRL entry.

Number of Desired Positive Roots

Indicates the limit to how many positive eigenvalues to be computed. This value can only be selected if Extraction Method is set to Inverse Power or Enhanced Inverse Power. This is the NDP field on the EIGB entry.

Number of Desired Negative Roots

Indicates the limit to how many negative eigenvalues to be computed. This value cannot be selected if Extraction Method is set to Inverse Power or Enhanced Inverse Power. This is the NDN field on the EIGB entry.

Diagnostic Output Level

Defines the level of desired output. This can take any integer value in the range of 0 through 3. This parameter can only be specified if Extraction Method is set to Lanczos. This is the MSGLVL field on the EIGRL Bulk Data entry.

Normalization Method

Indicates what type of eigenvalue normalization is to be done. This parameter can take one of two settings: Maximum or Point. This parameter cannot be specified if Extraction Method is set to Lanczos. This is the NORM field on the EIGB entry.

Chapter 3: Running an Analysis 331 Solution Parameters

Parameter Name

Main Index

Description

Normalization Point

Defines the point to be used in the normalization. This can only be selected if Normalization Method is set to Point. This parameter cannot be specified if Extraction Method is set to Lanczos. This is the G field on the EIGB entry.

Normalization Component

Defines the degree-of-freedom component at the Normalization Point to be used. This, too, can only be selected if Normalization Method is set to Point. This parameter cannot be specified if Extraction Method is set to Lanczos. This is the C field on the EIGB entry.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Complex Eigenvalue This subordinate form appears when Solution Parameters is selected on the Solution Type form when Complex Eigenvalue is selected. When you specify the Database Run and Formulation parameters (from the Solution Type form), Patran generates a SOL 107, 110, 28, or 29 input file.

Main Index

Chapter 3: Running an Analysis 333 Solution Parameters

The following table outlines the selections for Database Run and Formulation, and the altered SOL type for each. If you select Database Run, a Structured Solution Sequence (SOLs 107 or 110) will be selected. If you deselect Database Run a Rigid Format Solution Sequence (SOLs 28 or 29) will be selected. Database Run

Formulation

SOL

On

Direct

107

On

Modal

110

Off

Direct

28

Off

Modal

29

This is a list of data input available for defining the Complex Eigenvalue Solution Parameters. Parameter Name Automatic Constraints

Indicates that an AUTOSPC entry is requested, so that MSC Nastran will constrain model singularities.

Residual Vector

The Residual Vector Computation toggle writes RESVEC=YES or RESVEC=NO to the Case Control. This calculates residual vectors due to applied loads. The default is to calculate residual vectors.

Computation Shell Normal Tolerance Angle

Main Index

Description

Indicates that MSC Nastran will define grid point normals for a Faceted Shell Surface based on the Tolerance Angle. This data appears on a PARAM, SNORM entry.

Mass Calculation

Defines how the mass matrix is to be treated within MSC Nastran. This controls the setting of the COUPMASS parameter. This parameter can be set to either Coupled or Lumped. If set to Coupled, COUPMASS will be set to +1, otherwise, it will be set to -1.

Data Deck Echo

Indicates how the data file entry images are to be printed in the MSC Nastran print file. This controls the setting used for the ECHO Case Control command. This parameter can have one of three settings: Sorted, Unsorted, or None.

Plate Rz Stiffness Factor

Defines the in plane stiffness factor to be applied to shell elements. This defines the K6ROT parameter. This is an alternate method to suppress the grid point singularities and is intended primarily for geometric nonlinear analysis.

Maximum Printed Lines

Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.

Maximum Run Time

Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

334

Patran Interface to MSC Nastran Preference Guide Solution Parameters

Parameter Name

Description

Node ID for Wt. Gener.

Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

Default Initial Temperature

Specify the initial temperature.

Default Load Temperature

Specify load temperature.

Rigid Element Type

There is one rigid element type, Linear.

Struct. Damping Coeff.

Defines a global damping coefficient to applied. This defines the G parameter (e.g., PARAM, G, value).

• Complex Eigenvalue Brings up the Complex Eigenvalue Extraction form for defining the

complex eigenvalue extraction controls. • Real Eigenvalue

Brings up the Real Eigenvalue Extraction form for defining the real eigenvalue extraction controls.

• Dynamic Reduction

Brings up the Dynamic Reduction Parameters form for defining the dynamic reduction controls.

Results Output Format

Main Index

On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.

Chapter 3: Running an Analysis 335 Solution Parameters

Complex Eigenvalue Extraction

This subordinate form appears when the Complex Eigenvalue button is selected on the Complex Eigenvalue Solution Parameters form. Use this form to create an EIGC Bulk Data entry.

Main Index

336

Patran Interface to MSC Nastran Preference Guide Solution Parameters

This is a list of data input available for defining the Complex Eigenvalue Extraction. Parameter Name

Description

Extraction Method

Defines the method to use to extract the complex eigenvalues. This parameter can be set to any one of the following: Complex Lanczos, Upper Hessenberg, Inverse Power, or Determinate. This defines the setting of the METHOD field.

Alpha of Point A =

Defines the real component of the beginning of lines in the complex plane. These values cannot be selected if Extraction Method is set to Upper Hessenberg. This is a list of real values. They are the ALPHAAJ fields.

Omega of Point A =

Defines the imaginary component of the beginning of lines in the complex plane. These values cannot be selected if Extraction Method is set to Upper Hessenberg. This is a list of real values. They are the OMEGAAJ fields.

Alpha of Point B =

Defines the real component of the end of lines in the complex plane. These values cannot be selected if Extraction Method is set to Complex Lanczos or Upper Hessenberg. This is a list of real values. They are the ALPHABJ fields.

Omega of Point B =

Defines the imaginary component of the end of lines in the complex plane. These values cannot be selected if Extraction Method is set to Complex Lanczos or Upper Hessenberg. This is a list of real values. They are the OMEGABJ fields.

Width of Region =

Defines the width of the region in the complex plane. This value cannot be selected if Extraction Method is set to Complex Lanczos or Upper Hessenberg. This is a list of real values. They are the LJ fields.

Estimated Number of Roots =

Indicates an estimate of the number of eigenvalues to be located within the specified region. This value cannot be selected if Extraction Method is set to Complex Lanczos or Upper Hessenberg. This is a list of integer values. They are the NEJ fields.

Number of Desired Roots = Indicates the limit to how many eigenvalues to be computed within the specified region. This value cannot be selected if Extraction Method is set to Complex Lanczos or Upper Hessenberg. This is a list of integer values. They are the NDJ fields. Normalization Method

Main Index

Indicates what type of eigenvalue normalization is to be done. This parameter can take one of two settings: Maximum or Point. This is the NORM field on the EIGC entry.

Chapter 3: Running an Analysis 337 Solution Parameters

Parameter Name

Main Index

Description

Normalization Point

Defines the point to be used in the normalization. This is the G field on the EIGC Bulk Data entry.

Normalization Component

Defines the degree-of-freedom component at the Normalization Point to be used. This can only be selected if Extraction Method is set to Inverse Power or Determinate. This is the C field on the EIGC Bulk Data entry.

338

Patran Interface to MSC Nastran Preference Guide Solution Parameters

Frequency Response This subordinate form appears when Solution Parameters is selected on the Solution Type form when Frequency Response is selected. Patran generates a SOL 108, 111, 118, 26, or 30 input file when you specify the Database Run, Cyclic Symmetry, and Formulation parameters (from the Solution Type form).

The following table outlines the selections for Database Run, Formulation, and Cyclic Symmetry parameters, and the altered SOL type for each. If Database Run is selected, a Structured Solution Sequence (SOLs 108, 111, 118)

Main Index

Chapter 3: Running an Analysis 339 Solution Parameters

will be selected. If Database Run is deselected, a Rigid Format (SOLs 26 or 30) will be selected.

Database Run

Formulation

Cyclic Symmetry

SOL

On

Direct

Off

108

On

Direct

On

118

On

Modal

--

111

Off

Direct

--

26

Off

Modal

--

30

This is a list of data input, available for defining the Frequency Response Solution Parameters. Parameter Name Cyclic Symmetry

Indicates that this model is a sector of a cyclically repeating part, and the appropriate flags will be set. This can only be set if Database Run is selected and Formulation is set to Direct (SOL 118).

Automatic Constraints

Indicates that an AUTOSPC entry is requested, so that MSC Nastran will constrain model singularities.

Residual Vector

The Residual Vector Computation toggle writes RESVEC=YES or RESVEC=NO to the Case Control. This calculates residual vectors due to applied loads. The default is to calculate residual vectors.

Computation Shell Normal Tolerance Angle

Main Index

Description

Indicates that MSC Nastran will define grid point normals for a Faceted Shell Surface based on the Tolerance Angle. This data appears on a PARAM, SNORM entry.

Mass Calculation

Defines how the mass matrix is to be treated within MSC Nastran. This controls the setting of the COUPMASS parameter. This parameter can be set to either Coupled or Lumped. If set to Coupled, COUPMASS will be set to +1, otherwise, it will be set to -1.

Data Deck Echo

Indicates how the data file entry images are to be printed in the MSC Nastran print file. This controls the setting used for the ECHO Case Control command. This parameter can have one of three settings: Sorted, Unsorted, or None.

Plate Rz Stiffness Factor

Defines the in plane stiffness factor to be applied to shell elements. This defines the K6ROT parameter. This is an alternate method to suppress the grid point singularities and is intended primarily for geometric nonlinear analysis.

Maximum Printed Lines

Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.

Maximum Run Time

Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Parameter Name

Description

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

Node ID for Wt. Gener.

Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

Default Initial Temperature

Specify the initial temperature.

Default Load Temperature

Specify load temperature.

Rigid Element Type

There is one rigid element type, Linear.

Struct. Damping Coeff.

Defines a global damping coefficient to applied. This defines the G parameter (e.g., PARAM, G, value).

• Eigenvalue Extraction Calls up the Real Eigenvalue Extraction form that is used to define the

eigenvalue extraction controls. These parameters can only be specified if Formulation is set to Modal. • Dynamic Reduction

Main Index

Calls up another form that is used to define the dynamic reduction controls. These parameters can only be specified if Formulation is set to Modal.

Fatigue Parameters

Parameters on this form are used to run an MSC Nastran Embedded Fatigue analysis. See Fatigue Parameters Subform, 370.

Results Output Format

On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.

Chapter 3: Running an Analysis 341 Solution Parameters

Transient Response This subordinate form appears when Solution Parameters is selected on the Solution Type form when Transient Response is selected. Patran generates a SOL 109, 112, 27, or 31 input file, when you specify Database Run and Formulation parameters (from the Solution Type form).

Main Index

342

Patran Interface to MSC Nastran Preference Guide Solution Parameters

The following table outlines the selections for Database Run and Formulation, and the altered SOL type for each. If Database Run is selected, a Structured Solution Sequence (SOLs 109, 112) will be selected. If Database Run is deselected, a Rigid Format (SOLs 27 or 31) will be selected. Database Run

Formulation

SOL

On

Direct

109

On

Modal

112

Off

Direct

27

Off

Modal

31

This is a list of data input available for defining the Transient Solution Parameters. Parameter Name Automatic Constraints

Indicates that an AUTOSPC entry is requested, so that MSC Nastran will constrain model singularities.

Residual Vector Computation

The Residual Vector Computation toggle writes RESVEC=YES or RESVEC=NO to the Case Control. This calculates residual vectors due to applied loads. The default is to calculate residual vectors.

SOL 600 Run

Select this to perform a SOL 600 analysis.

SOL 700 Run

Select this to perform a SOL 700 analysis. To do this is necessary to use the Direct method.

Shell Normal

Indicates that MSC Nastran will define grid point normals for a Faceted Shell Surface based on the Tolerance Angle. This data appears on a PARAM, SNORM entry.

Tolerance Angle

Main Index

Description

Mass Calculation

Defines how the mass matrix will be treated within MSC Nastran. This controls the setting of the COUPMASS parameter. This parameter can be set to either Coupled or Lumped. If set to Coupled, COUPMASS will be set to +1, otherwise, it will be set to -1.

Data Deck Echo

Indicates how the data file entry images are to be printed in the MSC Nastran print file. This controls the setting used for the ECHO Case Control command. This parameter can have one of three settings: Sorted, Unsorted, or None.

Plate Rz Stiffness Factor

Defines the in plane stiffness factor to be applied to shell elements. This defines the K6ROT parameter. This is an alternate method to suppress the grid point singularities and is intended primarily for geometric nonlinear analysis.

Maximum Printed Lines

Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.

Chapter 3: Running an Analysis 343 Solution Parameters

Parameter Name

Description

Maximum Run Time

Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

Node ID for Wt. Gener.

Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

Default Initial Temperature Specify the initial temperature. Default Load Temperature

Specify load temperature.

Rigid Element Type

There is one rigid element type, Linear.

Struct. Damping Coeff.

Defines a global damping coefficient to applied. This defines the G parameter (e.g., PARAM, G, value.)

W3, Damping Factor

Defines W3 and W4 parameters. These parameters alter the damping characteristics of the model.

W4, Damping Factor1 • Eigenvalue

Extraction • Dynamic Reduction

Main Index

Calls up the Real Eigenvalue Extraction form that is used to define the eigenvalue extraction controls. These parameters can only be specified if Formulation is set to Modal. Calls up the Dynamic Reduction Parameters form that is used to define the dynamic reduction controls. These parameters can only be specified if Formulation is set to Modal.

Fatigue Parameters

Parameters on this form are used to run an MSC Nastran Embedded Fatigue analysis. See Fatigue Parameters Subform, 370.

Results Output Format

On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Nonlinear Transient This subordinate form appears when Solution Parameters is selected on the Solution Type form when Nonlinear Transient is selected. Use this form to generate either a SOL 99 or a SOL 129 input file, depending on the version of MSC Nastran indicated on the translation parameter form except as indicated below. Version 66 and below yields SOL 99 and Version 67 and above yields SOL 129.

Main Index

Chapter 3: Running an Analysis 345 Solution Parameters

This is a list of data input available for defining the Nonlinear Transient Solution Parameters. Parameter Name Automatic Constraints

Indicates that an AUTOSPC entry is requested, so that MSC Nastran will constrain model singularities.

Solution Sequence

The default solution sequence for Nonlinear Transient is 129, but can be changed to any one of the following if desired: 400, 600, 700. Only features of 129 are used in any case. For specific features particular to 600 or 700, please use the Implicit Nonlinear type or set the Analysis Type to Explicit Nonlinear, respectively.

Mass Calculation

Defines how the mass matrix is to be treated within MSC Nastran. This controls the setting of the COUPMASS parameter. This parameter can be set to either Coupled or Lumped. If set to Coupled, COUPMASS will be set to +1, otherwise, it will be set to -1.

Data Deck Echo

Indicates how the data file entry images are to be printed in theMSC Nastran print file. This controls the setting used for the ECHO Case Control command. This parameter can have one of three settings: Sorted, Unsorted, or None.

Plate Rz Stiffness Factor

Defines the in plane stiffness factor to be applied to shell elements. This defines the K6ROT parameter. This is an alternate method to suppress the grid point singularities and is intended primarily for geometric nonlinear analysis.

Maximum Printed Lines

Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.

Maximum Run Time

Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

Node ID for Wt. Gener.

Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

Struct. Damping Coeff.

Defines a global damping coefficient to applied. This defines the G parameter (e.g., PARAM, G, value.)

W3, Damping Factor

Define W3 and W4 parameters. These parameters alter the damping characteristics of the model.

W4, Damping Factor Results Output Format

Main Index

Description

On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Implicit Nonlinear This subordinate form appears when the Solution Parameters button is selected on the Solution Type form when Implicit Nonlinear is selected. Use this form to generate a SOL 400 or 600 input file.

Parameter Name

Main Index

Description

Solver / Options...

See Solver Options Subform (SOL 600), 348.

Contact Parameters...

See Contact Parameters Subform, 350.

Direct Text Input...

This subform is used to directly enter entries in the File Management, Executive Control, Case Control, and Bulk Data sections of the MSC Nastran input file. See Direct Text Input, 310.

Restart Parameters...

See Restart Parameters Subform, 361.

Advanced Job Control...

See Advanced Job Control Subform (SOL 600), 363.

Domain Decomposition...

See Domain Decomposition, 364.

Chapter 3: Running an Analysis 347 Solution Parameters

Parameter Name

Main Index

Description

Assumed Strain

For SOL 600, if ON, (default is ON), places the MARCASUM parameter into the input file. This forces all elements that can deal with assumed strain to use this formulation. This improves the bending behavior of Marc elements 3, 7, and 11. For SOL 400, the NLMOPTS entry is written with the ASSUM option. Again, this is a global setting and forces all elements that can use this formulation to adopt it.

Constant Dilatation

If ON, (default is OFF), places the MARCDILT parameter into the input file. This will force all elements that can deal with constant dilatation (for nearly incompressible analysis) to use this formulation. This affects Marc element types 7, 10, 11, 19, and 20 only and recommended for elastic-plastic and creep analysis. (SOL 600 only)

Plane Stress

Replaces plane strain elements with plane stress elements. (SOL 600 only)

Reduced Integration

Specifies that a lower number of element integration points be used to integrate exactly. (SOL 600 only)

Creep

For SOL 400, writes the NLMOPTS entry with the CREEP option defaults for creep analysis.

Shell Shear Correction

For SOL 400 (only), forces all shell elements using nonlinear formulations to use the shear correction. This writes the NLMOPTS entry with the TSHEAR option.

SOL 400 Run

Use this to select a SOL 400 simulation, instead of a SOL 600 simulation.The default solution sequence for Implicit Nonlinear is 600. By toggling the “SOL 400 Run” ON, Patran will write a SOL 400 input file. Not all features of SOL 600 are accessible using SOL 400, so use with caution and check your input file and results carefully.

Default Initial or Load Temperature

For SOL 400 allows for specification of a general initial temperature and a general loading temperature. TEMPD entries are written for both with Case Control TEMPERATURE(INITIAL) and TEMPERATURE(LOAD) entries calling out the corresponding TEMPD entries in the bulk data.

User Defined Services...

It allows defining the user defined services for SOL 400 analysis. To enable this functionary the SOL 400 check box must be selected and Nastran version must be 2013 or higher. See User Defined Services, 367.

Results Output Format...

On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.

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Solver Options Subform (SOL 600) Specifies the solver to be used in numerically inverting the system matrix of linear equilibrium equations.

Parameter Name

Main Index

Description

Inconsistent MPCs

There are three choices for dealing with problem MPCs, 1) Reorder (reorder the DOFs that are used to define the problem MPCs), 2) Continue (continue the analysis with no changes to the MPCs DOFs), or 3) Stop (stop the analysis).

Solver Type

Can be set to Direct Profile, Iterative Sparse, Direct Sparse, Hardware Sparse, Multifrontal Sparse (default) or External Sparse. For MSC Nastran 2010 or higher, Pardizo Direct Sparse and MUMPS Parallel Direct solvers are also supported.

Non-Symmetric

Specifies non-symmetric solution for Solver Types: Direct Profile, Multifrontal Sparse,or Pardizo Direct Sparse.

Bandwidth Optimization

Turns on the optimize option for the Direct Profile or Multifrontal Sparse solvers and uses the Sloan algorithm. Other solvers have their own optimizer and use it by default.

Non-Positive Definite

Turn this menu to ON to specify non-positive definite option. Valid for all solver types. Non Positive Definite is ON by default fo SOL 600. It is recommended to leave this menu set to Nastran Default. You may deselect this option by setting to OFF.

Chapter 3: Running an Analysis 349 Solution Parameters

Parameter Name

Main Index

Description

Memory

Defines the amount of work space in words. This can be left blank and the translator will automatically determine this based on model size.

Out-of-Core Threshold

For Hardware and Multifrontal Sparse solvers only. Default is 100. Represents the number of real*4 words in millions of words. Only for SGI computers running the IRIX operating system.

Number of Processes

Multiple treads can be specified for Pardiso(11) and Multifrontal (8) sparse solvers. The subsequent MSC Nastran job is submitted with the MRTHREAD parameter set accordingly. Multiple processors can be specified for MUMPS(12) solver. The subsequent MSC Nastran job is submitted with the MUMPSOLV parameter set accordingly. For DDM, by default the number of processes is set to the number of domains automatically. It can be manually changed if necessary.

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Contact Parameters Subform Defines options for detecting and handling contact.

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Chapter 3: Running an Analysis 351 Solution Parameters

Parameter Name

Main Index

Description

Contact Method

Node-to-Segment is the default contact method for Nastran. In Nastran 2010 Segment-to-Segment method was introduced. If set to Segmentto-Segment, the Friction and Augmentation forms are unique to this method. Various unsupported items under Contact Detection and Contact Separation are disabled.

Deformable-Deformable Method

In Double-Sided method, for each contact body pair, nodes of both bodies will be checked for contact. In Single-Sided method, for each contact body pair, only nodes of the lower-numbered body will be checked for contact. Results are dependent upon the order in which contact bodies are defined.

Optimize Constraint Equations

Use this to decrease the bandwidth of the model.

Contact Detection...

See Contact Detection Subform, 352.

Separation...

See Separation Subform, 354.

Friction Parameters...

See Friction Parameters Subform, 355.

Augmentation Parameters...

See Augmention Parameters, 358..

Enable Initial Contact

Click on checkbox to activate the capability for control of initial contact. The initial contact is for creating an MSC Nastran entry BCTABLE with ID = 0 to be used for increment 0. For SOL 600, this causes rigid contact bodies to be moved so they just touch adjacent flexible contact bodies. For SOL 101 and 400, a BCTABLE is used with ID = 0, which causes rigid contact bodies to be moved, as for SOL 600, and/or adjusting the coordinates of all active nodes on the surface of all deformable BCBODYs to remove any prestressed condition.

Initial Contact...

See Initial Contact Subform, 360.

Use Contact Table

Toggle button to enable or disable the use of Contact Table. This option gets activated only when the Enable Initial Contact check box is selected.

Penetration Check

This controls contact penetration checking, sometimes referred to as the increment splitting option. Available options are: At End of Increment, Per Iteration (default), Suppressed (Fixed), Suppressed (Adaptive). At End of Increment means penetration is checked at the end of a load increment. Per Iteration means that penetration is checked at the end of every iteration within an increment. If penetration is detected, increments are split. Suppress is to suppress this feature for Fixed and Adaptive load stepping types.

Reduce Printout of Surface Definition

This controls reduction of printout of surface definition.

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Contact Detection Subform

On the Contact Control Parameters subform, select Contact Detection... This form controls general contact parameters (BCPARA) for contact detection.

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Chapter 3: Running an Analysis 353 Solution Parameters

Parameter Name

Description

Distance Tolerance (ERROR)

Distance below which a node is considered touching a body (error). Leave the box blank to have Marc calculate the tolerance as the smaller of 1/20 element edge length or 1/4 shell thickness.

Bias on Tolerance (BIAS)

Contact tolerance BIAS factor. The value should be within the range of zero to one. Models with shell elements seem to be sensitive to this parameter. You may need to experiment with this value if you have shell element models that will not converge. The SOL 600 default is 0.9.

Suppress Bounding Box Check (ICHECK)

Turn ON this button if you want to suppress bounding box checking. This might eliminate penetration, but slows down the solution.

Check Layers

For contact bodies composed of shell elements (ISHELL), this option menu chooses the layers to be checked. Available options are: Top and Bottom, Top Only, Bottom Only. Check Layers and Ignore Thickness combination enters the appropriate flag in the 10th field of the 2nd data block.

Ignore Thickness

Turn this button ON to ignore shell thickness. Check Layers and Ignore Thickness combination enters the appropriate flag in the 10th field of the 2nd data block.

Activate Quadratic Contact Use this to detect the contact of the edges of quadratic elements (LINQUAD) (midside nodes). Activate 3D Beam-Beam Contact (BEAMB)

Turn this button ON to activate 3D beam-beam contact. Activate 3D Beam-Beam Contact enters a one(1) in the 13th field of the 2nd data block. This creates the MSC Nastran Bulk Data entry BCPARA, and uses the entry BEAMP.

Permanent Gluing (NLGLUE)

Turn this toggle ON to activate Permanent Gluing. This creates the MSC Nastran Bulk Data entry: BCPARA 0 NLGLUE 0. If this toggle is OFF, Patran writes out the MSC Nastran Bulk Data entry: BCPARA 0, NLGLUE 1.

Note that for Segment-to-Segment contact, not all parameters are available. Those not available are disabled.

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Separation Subform

On the Contact Control Parameters subform, select Separation... This form controls general contact parameters for contact separation.

Parameter Name

Main Index

Description

Maximum Separations

Maximum number of separations allowed in each increment. Maximum Separations is entered in the 6th field of the 2nd data block. Default is 9999.

Retain Value on NCYCLE

Turn ON this button if you do not want to reset NCYCLE to zero when separation occurs. This speeds up the solution, but might result in instabilities. You can not set this and Suppress Bounding Box simultaneously. Retain Value of NCYCLE enters a three(3) in field 8 of the 2nd data block.

Increment

Specifies whether chattering is allowed or not. Increment and Chattering enters the appropriate flag in the 9th field of the 2nd data block.

Chattering

Specifies the separation criterion (forces or stresses) and the critical value at which the separation will take place. Increment and Chattering enters the appropriate flag in the 9th field of the 2nd data block.

Chapter 3: Running an Analysis 355 Solution Parameters

Parameter Name

Description

Separation Criterion

Specifies in which increment (current or next) the separation is allowed to occur. Separation Criterion enters a one(1) in the 12th field of the 2nd data block if separation is based on stresses.

Force Value Stress Value

Force/Stress Value is placed in the 5th field of the 3rd data block.

Note that for Segment-to-Segment contact, not all parameters are available. Those not available are disabled. Friction Parameters Subform

On the Contact Control Parameters subform, select Friction Parameters...

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Note that different forms appear depending on whether Node-to-Segment or Segment-to-Segment contact is selected on the Contact Parameters form.

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Chapter 3: Running an Analysis 357 Solution Parameters

Parameter Name Friction Type

Description Available options for friction Type are: None (default), Shear (for metal forming), Coulomb (for normal contact), Shear for Rolling, Coulomb for Rolling, Stick-Slip, Bilinear Shear, and Bilinear Coulomb. The MSC Nastran entry BCPARA is written to the .bdf file, with FTYPE used. Type and Method: places 0, 1, 2, 3, 4, or 5 in the 4th field of the 2nd data block depending on fiction type, and places a 0 or 1 in the 5th field of the 2rd data block for friction based on nodal forces or nodal stresses, respectively for Coulomb fiction. Stick-Slip is a Coulomb type friction. Segment to Segment contact only supports Coulomb and Shear Bilinear (Displacement) methods currently.

Method

For Coulomb type of friction models (options 2, 4, and 5 above), there are 2 methods for computing friction: Nodal Stress, Nodal Force (default). Type and Method: places 0, 1, 2, 3, 4, or 5 in the 4th field of the 2nd data block depending on fiction type, and places a 0 or 1 in the 5th field of the 2rd data block for friction based on nodal forces or nodal stresses, respectively for Coulomb fiction. Segment to Segment contact only supports Coulomb and Shear Bilinear (Displacement) methods currently.

Main Index

Relative Sliding Velocity

Critical value for sliding velocity below which surfaces will be simulated as sticking. Relative Sliding Velocity is placed in the 1st field of the 3rd data block for all friction models except Stick-Slip.

Transition Region

Slip-to-Stick transition region. Transition Region is placed in the 1st field of the 3rd data block for Stick-Slip model.

Multiplier to Friction Coefficient

Friction coefficient multiplier. Multiplier to Friction Coefficient and Friction Force Tolerance are placed in the 7th and 8th field of the 3rd data block respectively for the Stick-Slip friction model.

Friction Force Tolerance

Friction Force Tolerance. Multiplier to Friction Coefficient and Friction Force Tolerance are placed in the 7th and 8th field of the 3rd data block respectively for the Stick-Slip friction model.

Non-Symmetric Matrix

For Segment-to-Segment contact this value is written to the BCPARA option. Note that you must select a solver that supports non-symmetric matrices for this to work, such as Pardiso or MUMPS. This is done on the Solvers/Options, 465 form.

Heat Generation Conversion Factor

A factor related to how much heat is generated by the friction process. Not available in Nastran currently.

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Augmention Parameters

The user also has a choice of the augmentation procedure used to impose the contact constraint when using the Segment-to-Segment (STS) contact method. The default of no augmentation is generally recommended. This leads to a cost effective solution, but may show a minimal amount of penetration inherent in the penalty method. If the penetration is not acceptable, the augmentation procedure can be activated, which can be based on a constant or bilinear penetration field per contact segment. The augmentation procedure based on a bilinear field is not recommended for lower-order elements. Note that the augmentation procedure only affects contact between deformable bodies. If there is contact between a deformable and a rigid body, the augmentation procedure is always applied. When the STS procedure is used, separation is based upon absolute stress based separation.

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Chapter 3: Running an Analysis 359 Solution Parameters

Parameter Name Augmentation (Normal) Penalty Factor Penetration Distance

Description If Segment-to-Segment contact method is specified on the Contact Parameters form, the Augmentation parameters are set here. The Normal Augmentation method may be set to None, Automatic, Constant or Bilinear. Automatic is a combination of Constant and Bilinear where augmentation is based on constant penetration for linear elements and on a bilinear penetration for quadratic elements. If no penalty factor or penetration distances are specified, Nastran will automatically determine them. The appropriate BCPARA entries are written.

Augmentation (Tangential) Not supported by Nastran at this time. Penalty Factor Slip Distance

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Initial Contact Subform

On the Contact Control Parameters subform, select Initial Contact...

This form works exactly as the Contact Table form for a standard Subcase, except that a unique BCTABLE with ID 0 (zero) is written. If not specified, then the BCTABLE specified in the first subcase is also written as BCTABLE with ID zero. See Contact Table, 456 for the operation of the Contact Table form.

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Chapter 3: Running an Analysis 361 Solution Parameters

Restart Parameters Subform Includes a Restart option in the MSC Nastran input file. Restarts are only supported for SOL 600 in the current release.

Parameter Name

Main Index

Description

Restart Type

You can Write restart data, Read restart data and Read and Write restart data. The default is None for no restart data.

Create Continuous Results File

If when restarting a job, you wish the results form the previous run to be copied into the new POST file, then turn this ON. This will place the RESTART or RESTART LAST options before the POST option in the input file. Otherwise they are placed after the POST option which flags Marc not to copy the results to the new POST file. If you turn this ON, you must have a restarname.t16 and/or restartname.t19 file in your local directory or the Marc analysis will fail.

Last Converged Increment

Writes a RESTART LAST instead of a RESTART option. ON by default.

Reauto

OFF by default. This places a REAUTO option in the input file. Any additional data needed for the REAUTO option are extracted from the first Load Step information for the restart job. Only if the Restart Type is set to Read or Read and Write is the REAUTO written or the toggle visible to the user.

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Parameter Name

Main Index

Description

Restart from Increment

Defines the increment to be read from the file specified in the Select Restart File form. This is entered in the 3rd data field on the 2nd card of the RESTART option. It is only requested when Restart Type is set to Read or Read and Write. The last increment on the restart file is used for the RESTART LAST option when Last Converged Increment is ON.

Increments Between Writing Data

Defines the number of increments between writing data to the restart file. This is entered in the 2nd data field on the 2nd card of the RESTART option. It is only requested when Restart Type is set to Write or Read and Write. When Last Converted Increment is ON, this is the 4th field of the 2nd data block of the RESTART LAST option.

Select Restart File...

This brings up a file browser to select the restart file when the Restart Type is set to Read or Read and Write. This file is specified on the command line for invoking the Marc solver using the -r option.

Chapter 3: Running an Analysis 363 Solution Parameters

Advanced Job Control Subform (SOL 600) Sets alternate versions of the solver and alternate formats for the results file, for SOL 600 jobs.

Parameter Name Marc Version

Specifies the version of MSC.Marc to run the analysis.

Marc Results File Format

Specifies the file format for the output from the analysis.

Marc Results File Type

Defines the binary output and/or text format of output from the analysis. Binary is recommended since .t16 files are linarily compatible across platforms and take up less space.

Marc scratch files w/ Nastran’s

Main Index

Description

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Parameter Name

Description

Use Environment Variables Use to enable the use of environment variables. Suppress Non-SOLMARC Errors

Suppress errors that are not SOL 600 errors.

Submit Marc Job

Submit SOL 600 jobs to Marc.

Use Marc License

Use this to search for, then use Marc licenses.

Copy Marc Files

Make copies of Marc files; for example copy .t16 file.

Filter Marc Text Delete Marc Files

Delete Marc files after the corresponding Patran files are created.

Gradually Release Constraints Analysis Control Defaults

Creates the Nastran Bulk Data entry PARAM, MARCDEF. Its three values are Nastran Development (recommended by Nastran development; Marc SHELL_SECT parameter is set to 11), MarcMentat (current Marc standard), Marc Development (recommended by both Marc and Nastran development).

Marc Submit Command

Locates the submit command to run the MSC.Marc analysis (optional). For Specify Full Command its list box will be un-ghosted.

Domain Decomposition Domain Decomposition is used to partition the model into seperate parts (domains) for parallel processing. The Method used to do this is named Domain Decomposition Method (DDM). This form designates that domain decomposition be done manually, semi-automatically, or automatically, for either SOL 400 or SOL 600 jobs.

Main Index

Chapter 3: Running an Analysis 365 Solution Parameters

Main Index

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Parameter Name

Main Index

Description

Decomposition Method

Set this to Automatic if you wish MSC Nastran to automatically create the domains during analysis run time. Set to Semi-Automatic if you wish to have Patran automatically break the model into domains which can be visualized before submittal. Set to Manual to have full control over the domains. This requires the creation of the groups before they can be selected here in this form and associated to a domain.

Number of Domains

This determines how many domains are to be created. When you change this number and press the Enter or Return key, the spread sheet updates with this number of rows. The default is 1. This corresponds to the number of CPUs desired to run the job. For the Automatic method, this is the only input that is required and the spreadsheet is not visible.

Model or Current Group

This is for choosing a part of the model to decompose for parallel processing: Model -- decompose all of the model, Current Group -decompose just the current group. This choice must be consistent with what part of the model is specified for analysis (Analysis: Analyze / Entire Model or Selected Group). This is only active if Decomposition Method is set to Automatic or Semi-Automatic.

Metis Method

There are three Methods that can be used to partition the Model or Current Group into Domains. They are, 1) Nodal Position, 2) Element Topology, or 3) Best (a procedure that accounts for the best of the nodal, element, or vector type algorithms). This method can only be used if Decomposition Method is set to Automatic.

Domain Island Removal

Using this option causes some parts of disjoint domains (domain islands) to be combined with adjacent domains. This can only be used if Decomposition Method is set to Automatic.

Coarse Graph

Using this option sometimes produces domain islands (disjoint domains). This option (the default) is recommended to reduce the time to decompose the initial global domain. Use this only if there is a definite need for a better decomposition. This can only be used if Decomposition Method is set to Automatic.

Single POST File

If more than one CPU processor is used to solve the problem, the seperate/multiple results files can be compiled into a single file for postprocessing using Single POST File.

Create

Click Create to create Domain Information spreadsheet rows. After doing this the number of rows will equal the value of Number of Domains in the form. If Decomposition Method is set to Manual, the previously created group names will be selectable in Select a Group window at the bottom.

Chapter 3: Running an Analysis 367 Solution Parameters

Parameter Name

Description

Visualize

This is used to display groups. Select a group name for the heading Domain Information under Group. Click Visualize to display just that group. This can be done for some or all of the groups.

Reset Graphics

Click Reset Graphics to reset the viewport graphics.

Validate

This is for validating (checking) that the domains are not disjoint. For two adjacent domains, the nodes at the interface of the domains must be in both domains.

Domain Information

The window with the definition of each Domain. For a given Domain there is a corresponding unique Group name.

User Defined Services This form defines the options for Patran pre-processing (GUI) support for the MSC Nastran User Defined Services (UDS) specific to the SOL 400 analysis.

Figure 3-1

Main Index

UDS Form Simple

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

.

Figure 3-2

UDS Form Advanced

Parameter Name UDS Type

Provides you with an option to select between the Simple or Advanced UDS forms.

Nastran UDS Environment Variables

This frame contains the following UDS environment variables.

MSC_SDK_PATH

MSC_SDK_PATH and User Source File fields appear on the simple form and show the current settings of the variables, whether they are defined or not. If the variables are defined then the textboxes show the (the actual settings of the variables). If variables are not defined then the textboxes show UNDEFINED.

User Source File

Main Index

Description

Chapter 3: Running an Analysis 369 Solution Parameters

Parameter Name SCA_RESOURCE_DIR SCA_LIBRARY_PATH

Main Index

Description SCA_RESOURCE_DIR and SCA_LIBRARY_PATH fields appear on the Advanced form and show the current settings of the variables, whether they are defined or not. If the variables are defined then the textboxes show the (the actual settings of the variables) and a "View…" button. If variables are not defined then the textboxes show UNDEFINED and a "Browse…" button.

Number of UDS Map

Displays the number of UDS in the current job.

Update Rows

Clicking Update Rows adds the number of rows defined in the Number of UDS Map text box in the UDS Map spreadsheet section.

UDS Map

This spreadsheet contains the mapping of the Patran entity to the UDS service name that will be used. The number of rows of this spreadsheet is set by the value in the Number of UDS data box.

Service Name

Nastran UDS service name.

Service Identifier

Unique service identifier made of 8 characters.

Object

Patran UDS entity name (Material UDS Property, Element UDS property, Contact Body and Runtime Info).

Optional Input

Optional input data (integer, real, characters) required for a user subroutine. Clicking on the cell will open a spreadsheet where you can enter the data.

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Fatigue Parameters Subform Defines options for defining an MSC Nastran Embedded Fatigue analysis. All the parameters defined on this subform are written to the FTGPARM bulk data entry.

In order to run a successful MSC Nastran Embedded Fatigue analysis, an S-N or ε-N constitutive model (or both) must be defined for the elements of interest (shells and solid elements only - see Stress-Life (SN) and Strain Life (eN), Spot Weld (Top and Bottom Sheet), Seam Weld (Stiff and Flexible), 92). An output request for fatigue life must be made (see Output Requests, 478). An S-N or ε-N analysis must be turned on when setting up the analysis for Linear Static, Normal Modes, or Transient Response as defined on this form. And a cyclic loading sequence must be defined (see Subcase Select, 515) above the subcase level. Optionally, various fatigue parameters can be defined as element properties such as surface finish (see 2D Element Properties, 156) for shell and solid elements only. Only a brief explanation is given here of each parameters. For more detail on how to set up and perform an MSC Nastran Embedded Fatigue analysis using Patran, please see the MSC Nastran Fatigue Analysis User’s Guidefor time domain SOLutions 101/103/112. See the MSC Nastran Embedded Vibration Fatigue User’s Guide for frequency domain solutions SOLs 108 and 111. For details on the FTGPARM entry, please see the FTGPARM (p. mcdxii) in the MSC Nastran Quick Reference Guide.

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Chapter 3: Running an Analysis 371 Solution Parameters

Brief descriptions of each option on this fatigue parameter form are given here for time domain SOLutions 101/103/112. See the next table for frequency domain SOLutions 108 and 111. Parameter Name General Parameters

Description Generic parameters are global to most any fatigue analysis whether it be S-N or ε-N:

Stress Units: • The Stress Units must be specified for proper conversion during the fatigue analysis. A DTI,UNITS bulk data entry is written defining the units of stress. Stress Combination: • Stresses or strains are resolved to the specified scalar values via the Stress Combination. The stress/strain tensor (time history) data is transformed to this scalar stress/strain parameter before cycle counting. It is NOT recommended to use unsigned values (Max Principal, von Mises, or Max Shear) unless you are confident in your analysis skills as this can lead to incorrect or misleading stress ranges being calculated. For Critical Plane, the in-plane principal stresses are determined at 10 degree intervals. Note that using Critical Plane increases the analysis time by 18 times. The worst angle is reported in the analysis. Results Location: • Fatigue results can be requested at the nodes (Nodal Averaged), element nodes (Element Nodal) or the element centroids (Element Center). Stresses are averaged at the nodes for the default Nodal Averaged method using Nastran’s grid point stress generator; otherwise elemental stresses at the nodes or element centroid are used in the fatigue calculation. Element Nodal results in fatigue lives at each node of each element. Thus postprocessing averages fatigue lives at the nodes. Using Nodal Averaged does not average fatigue lives at the nodes as there is only one results per node. See Nodal Averaging mode of this form below. Recovery: • Stress and strains are recovered from the analysis based on Nastran’s recovery method, which can be set here. See the STRESS or STRAIN case control description of these values. Default is at the Corners for Nodal Averaged and Element Nodal, or at the Center for Element Center. Layer: • For shell elements, fatigue lives are reported in Nastran’s output file (f06 file) for the Top, Bottom, or Worst case (default) layer. This is an printed output request only. Fatigue lives at both top and bottom are calculated during the analysis and available for Patran to post process, thus allowing you to plot worst case layer or specifically top or bottom.

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Parameter Name

Description

Interpolation: • Interpolation limits can be set when using multiple digitized (tabular) S-N curves. Use Max Curve uses the maximum defined S-N data if the look-up stress goes beyond that defined by the digitized curves. Or you can request that it Extrapolate. Level of Message: • Messaging level written to a log file. Use this for debugging purposes only. Setting this value greater than three (3) can results in performance degradation. Results are output to the jobname.dtout and jobname.config files. Number of Threads: • The number of processing treads can be specified for parallel processing large models to speed up calculations on machines with multiple CPUs. Set to zero (0) for automatic usage of available CPUs. Certainty of Survival: • A certainty of survival can be defined to take into consideration the statistical scatter of the stress or strain-life material data. Overall Scale Factor: • An overall scale factor can be applied to the resultant cyclic stresses or strains. Top Stress %: • A filter can be applied to report results for only a top percentage of the highest stressed entities. See also the next entry. Top Damage %: • A filter can also be applied to report results for only a top percentage of the highest damaged entities. When used in conjunction with the top percentage stressed elements, this is called a 3-pass analysis where the 1st pass reduces the number of entities based on the top stressed elements, the 2nd pass uses compressed time histories to quickly determine and filter only the highest damaged elements, and then the 3rd pass uses the fully populated time histories on only the remaining entities to get the actual damage.

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SN Parameters

This toggle must be ON in order for a general Stress-Life (S-N) fatigue analysis to be performed. Mean stress corrections can be set to Goodman, Gerber, or no mean stress correction. The stresses used in the fatigue analysis for each subcase can be output to the MSC Nastran F06 file (Print) and/or data block (Print or Plot) for postprocessing.

eN Parameters

This toggle must be ON in order for an Strain-Life (ε-N) fatigue analysis to be performed. Mean stress corrections can be set to SmithTopper-Watson, Morrow, or no mean stress correction. Stress or strain can be specified as the supplied finite element (FE) results (SN must use stresses) and a plasticity correction method. The stresses or strains used in the fatigue analysis for each subcase can be output to the MSC Nastran F06 file (Print) and/or data block (Print or Plot) for postprocessing.

Chapter 3: Running an Analysis 373 Solution Parameters

Parameter Name

Description

Factor of Safety

A factor of safety analysis can be requested where a target life is specified and the analysis returns a scale factor that if applied to the cyclic stresses or strains, would result in the target life being achieved.

Time History Compression

To speed up analyses of jobs consisting or extremely long, complex cyclic loading, time history compression routines can be applied to remove less damaging and inconsequential cycles from the cyclic loading.

Static Damage Check

Turn this on if you wish to check for static failure. By default the program will simply warn you if static failure occurs by checking against the ultimate tensile strength (UTS). Optionally you can stop the analysis immediately. If this is ON, the DAMAGE keyword and parameters are written to the FTGPARM entry. Any entity experiencing static failure is automatically assigned the damage value set in the Static Failure Damage data box. The Maximum Damage databox sets an upper limit on the amount of damage that can be predicted for any given cycle. Setting this to >1.0 shows how much unacceptable damage has accumulated. The Damage Floor data box sets a lower limit. If a cycle has less than this predicted damage, the damage is set to zero.

Biaxial/Multiaxial Assessment

Turn this ON to run a multiaxial assessment. The method can be set to None, Simple, Standard, or Auto. Simple does a simple biaxiality analysis only. Standard calculates the non-proportionality and Auto may recalculate the fatigue damage based on the results of the assessment. This functionality is available for standard S-N, e-N and Seam Weld analysis only and has limitations if a factor of safety (FOS) analysis has also been requested (only Simple is valid in this case). If Auto is selected, the stress/strain combination method is ignored and the program determines whether to use critical plane or absolute maximum principal stress. Auto is also not compatible with fatigue analysis os seam welds. For Auto, the Zero Stress defines the stress range below which no damage is assumed; the Gate is the stress below which the biaxiality ratio is set to zero to prevent small stresses from adversely affecting the biaxiality calculations. It is recommended that the other limits be left at their defaults. If your model contains solid elements and you wish to do a biaxial/multiaxial assessment, you need to turn ON the Surface Resolved Stresses/Strains toggle. This causes MSC Nastran to

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Parameter Name Surface Resolved Stresses/Strains

Description If your model contains solid elements and you wish to do a biaxial/multiaxial assessment, you need to turn this toggle ON. This causes MSC Nastran to internally generate very thin shell elements on the free surfaces of the solid elements. The stresses/strains in these elements are then used in the fatigue analysis and biaxial/multiaxial assessment. No fatigue analysis is done using the stresses from the actual solid elements in this case. If the toggle is OFF, then fatigue analysis of solid elements proceeds as normal, but biaxial/multiaxial assessment is only done on shell elements, if there are any. The solid elements do not participate in the assessment since a 2D stress state is required. With the toggle ON, you can specify a starting element ID for the internally generated element if desired. By default the next highest element ID in the model is used (set the value to “#”).

Spot Weld Fatigue Analysis Turn this ON to do fatigue analysis of spot welds. It is assumed that proper elements have been defined as the spot welds (either stiff bars, actual spot weld connectors, or single HEX elements attached to the top and bottom sheet by RBE3 elements. If an S-N analysis is turned on, then a standard fatigue analysis is also performed. Elements defined as spot weld elements take precedence over a standard fatigue analysis in the case where the same elements are defined for both. Fatigue results are calculated at the top, middle, and bottom of the spot weld at various Calculation Angles (18 by default) around the circumference of the weld. If Calculate Torsion is turned ON, then an additional fatigue calculation is done for torsional stresses (note that this is not generally recommended as it really requires different material properties - so separate analyses are likely necessary). Three (3) sheet spot welds are also possible and the middle sheet result is ignored unless the Process Middle Sheet toggle is turned ON. Only one type of Mean Stress Correction is possible using the FKM (Simple) method where M1=M2=M3=M4=-MSS defined in the material constitutive model.

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Chapter 3: Running an Analysis 375 Solution Parameters

Parameter Name

Description

Seam Weld Fatigue Analysis

Turn this ON to do fatigue analysis of seam welds. It is assumed that proper elements location identification (grouping) has been done to define the toe, root, and/or throat elements of the seam welds. If an SN analysis is turned on, then a standard fatigue analysis is also performed. Elements defined as seam weld elements take precedence over a standard fatigue analysis in case the same elements are defined for both. You must identify the Stress Combination parameter to be used and only one Mean Stress Correction method is available (FKM) where M1-M4 are defined on the material constitutive model. A Thickness Correction can be applied also and the thicknesses are automatically extracted from the shell properties by Nastran to apply the correction.

Nodal Averaging

If you have set the Results Location on the General Parameters mode of this form to Nodal Averaging, then you can control how Nastran computes the grid point stresses. By default the Method is Topological, the Output System is Basic (Patran global system), and Radius is used as the Positive Fiber Direction. Use Geometric if you have large discontinuities in your model. The settings on this form for grid point stress/strain extraction are identical to that for the GPSTRESS case control output request from Nastran and you are referred to that documentation.

Brief descriptions of each option on this fatigue parameter form are given here for frequency domain SOLutions 108/111. See the previous table for time domain SOLutions 101/103/111. Parameter Name General Parameters

Description Generic parameters are global to most any fatigue analysis whether it be S-N or ε-N:

Stress Units: • The Stress Units must be specified for proper conversion during the fatigue analysis. A DTI,UNITS bulk data entry is written defining the units of stress. These are the same as the time domain settings. Stress Combination: • Stresses or strains are resolved to the specified scalar values via the Stress Combination. The stress/strain tensor (time history) data is transformed to this scalar stress/strain parameter before cycle counting. Absolute Maximum Principal is the default. Fast Max. Principal speeds up the analysis significantly but is not as accurate. Signed vonMises is typically the most common and generally accepted stress parameter for frequency domain fatigue analysis. Individual component stresses are also available.

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Parameter Name

Description

Results Location: • Fatigue results can be requested at the nodes (Nodal Averaged), element nodes (Element Nodal) or the element centroids (Element Center). The stress transfer functions are averaged at the nodes for the default Nodal Averaged method. When using this method, please ensure the stress contribution from each element at the nodes is in a consistent coordinate system. Using Element Nodal results in fatigue lives at each node of each element. Thus postprocessing averages fatigue lives at the nodes. Using Nodal Averaged does not average fatigue lives at the nodes as there is only one results per node. Recovery: • Stress and strains are recovered from the analysis based on Nastran’s recovery method, which can be set here. See the STRESS or STRAIN case control description of these values. Default is at the Corners for Nodal Averaged and Element Nodal, or at the Center for Element Center. Layer: • For shell elements, fatigue lives are reported in Nastran’s output file (f06 file) for the Top, Bottom, or Worst case (default) layer. This is an printed output request only. Fatigue lives at both top and bottom are calculated during the analysis and available for Patran to post process, thus allowing you to plot worst case layer or specifically top or bottom. Level of Message: • Messaging level written to external files. Setting this to anything other than Standard (default) can results in performance degradation and large output. If set to +Response PSDs, input and output PSDs are written for every requested entity. If set to +Rainflow Damage, both PSD and PDF rainflow data is written for every requested entity. A limited set of entities should be used when setting this option. The files written are CSV type files that can be opened directly in MS Excel and plotted or use a special Patran utility found under the Tools | Results | NEF Random Vibration... pull down menu. Top RMS % Filter: • A filter can be applied to report results for only a top percentage of the highest stressed entities based on RMS stress level. This is set as a percentage meaning that only the set percentage of entities with the highest RMS are retained. Stress/Strain Life (S-N/eN)

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This mode of the form allows for various settings of the fatigue analysis.

Chapter 3: Running an Analysis 377 Solution Parameters

Parameter Name

Description

Run Fatigue Analysis This toggle must be ON in order for a general Stress-Life (S-N) or Strain-Life (ε-N) fatigue analysis to be performed. If this toggle is OFF, no fatigue damage is calculated. If this toggle is turned OFF, the Random Analysis Only toggle is turned ON and vice-versa. Please note that a fatigue analysis or the random only analysis is only successful if fatigue material properties exist, fatigue output has been requested, and a proper fatigue loading sequence has been defined. Random Analysis Only Turn this toggle ON if wish for the analysis to proceed with only the random vibration portion and skip the subsequent fatigue analysis to be performed. If this toggle is ON, no fatigue damage is calculated. If this toggle is turned OFF, the Run Fatigue Analysis toggle is turned ON and vice-versa. Please note that a fatigue analysis or the random only analysis is only successful if fatigue material properties exist, fatigue output has been requested, and a proper fatigue loading sequence has been defined. Option An S-N or an ε-N analysis is performed based on the material properties. Thus the default Automatic should suffice for most situations. If however you have both S-N and ε-N material constitutive models defined and you wish to force the S-N or the ε-N analysis, set this to one or the other. Mean Stress Correction Mean stress corrections can be set to one of the options on this pull down menu. Note that you must have some stress offset defined in order for this to be effective. Plasticity Correction Used if performing a strain-life (ε-N) analysis. Only Neuber method of notch correction is currently available. Output Fully Populated Turn this toggle ON if you wish MSC Nastran to output a CSV type Material Curves file containing the fully derived material curves used in the analysis. These are x-y type files and can be plotted using Patran’s standard XY Plot application or read directly into MS Excel for viewing and plotting. Analysis Settings

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These settings are specific to frequency domain vibration fatigue analysis. Generally these setting defaults are fine. For pure sine wave (deterministic loading) set the Rainflow Method to Sines. For random or harmonic loading, Dirlik is the preferred method. You are referred to MSC Nastran’s documentation for explanations of these settings.

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DDAM DDAM is an acronym for Dynamic Design Analysis Method, or DDAM is a methodology for analyzing ship-mounted equipment that the US Navy uses in the event of a near-miss underwater. Most FEA products follow the DDAM methodology, as does any hand calculation. MSC has made several improvements to its products that make DDAM easier to use. To accommodate the special spectrum and summing conventions MSC made several modifications to MSC Nastran. A DMAP alter in MSC Nastran puts out data important for a DDAM analysis. A standalone Fortran program reads the MSC Nastran data, calculates the spectral data, formats DDAM run information, and sends data back to MSC Nastran for further postprocessing. MSC’s DDAM has the following capabilities. • Calculates all three shock directions simultaneously. • Automatically calculates the appropriate spectra from input of the coefficients. • Performs the NRL sum. • Contains modal selection following 3010 Rev 1 convention. • Provides manual mode selection if needed. • Provides mode-by-mode output if desired. • Uses all available MSC Nastran elements. • Provides NRL summed output in MSC Nastran OP2 format for use with most postprocessors. • Offers an alternate coefficient input method is available that avoids using the Fortran program,

but the classified coefficients must be entered directly in the data file. • Has unlimited model size. • Uses MSC’s Lanczos Eigenvalue solver for fast solutions.

DDAM has the following limitations. • All base input points must be rigidly connected to a single grid flagged on a SUPORT entry. • There is no easy method to handle closely spaced modes as defined by 3010. • MSC Nastran printed output (.f06 file) is not labeled well, and must be used carefully in order to

avoid mistakes. This is especially true of the mode-by-mode output. • A DDAM data file will not read into Patran/MSC.FEA completely. • .XDB output not available for NRL summed quantities • MSC Nastran requires additional input switch to be toggled in Patran in order to plot NRL

summed von Mises and combined beam stresses. • MSC Nastran does not calculate beam and bar shear stresses. They are not included in the von

Mises and combined stresses reported by MSC Nastran DDAM.

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Chapter 3: Running an Analysis 379 Solution Parameters

DDAM in Patran DDAM in MSC Nastran is a process that involves three main parts, and a number of smaller parts. The entire procedure is accessed from a simple interface in Patran that integrates the process. • Part 1, Modal Analysis - A modal analysis is run in MSC Nastran. This supplies the frequencies,

mode shapes and modal participation for the model. • Part 2, Spectrum Generation – Using the output from Part 1, you can use a Fortran program to

calculate the shock spectrum. This is based on the DDS-072 or NRL 1396 documents, or you can manually enter your own spectrum. • Part 3, Spectrum Application and Data Recovery – The calculated spectrum from Part 2 is

applied to the mode shapes calculated in Part 1, and the results are calculated on a mode-bymode basis. The results from this are then summed using an NRL sum to produce results, one set for each shock direction. The Patran interface presents you with a selection of options to calculate the spectrum and sum the results. The options are stored, and when the MSC Nastran modal analysis completes, the Fortran program automatically starts, using the stored options to drive it. MSC Nastran automatically resumes after the completion of the Fortran program and finishes the analysis. During is process, a number of files will be created that are inputs and outputs from this process, all named jobname.xxx using the jobname chosen in Patran. The most important files are: jobname.ddd – the DDAM potions file that drives the Fortran program jobname.f11 – the modal information needed to calculate the spectrum jobname.f13 – the calculated spectra information for input back into MSC Nastran jobname.ver – modal verification file jobname.opw – Nastran OP2 file with the mode shapes jobname.opx – Nastran op2 file with the NRL summed results for x-shock jobname.opy – Nastran op2 file with the NRL summed results for y-shock jobname.opz – Nastran op2 file with the NRL summed results for z-shock Once the run is complete, you can look over both the results and the modal verification file. If the results are not as expected or desired, there are a number of more advanced capabilities of this DDAM procedure for more control over the process. These include some that are on the Patran forms (changes in 80% criterion, minimum G value) and ones that can be accessed using the Patran Direct Text capability (modeby-mode output, specific mode selection). DDAM Model Preparation

In order to run DDAM, all of the fixed base points (excitation inputs) in the model must be rigidly connected to a single point. The MSC Nastran RBE2 element is used for this, connecting the independent node (the SUPORT point) to all of the other fixed base/excitation points (dependent grids) in all 6 degrees of freedom. This point is flagged for the SUPORT entry in the DDAM setup. It is not necessary that this

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point is separated (spatially) from the other input points, you can select one of the base points to be the SUPORT point, as long as all the excitation points are then connected to it. It is not advisable to have any other translational constraints in the model, as they will remove modal mass from the model and the 80% criterion will not necessarily be correct, and the model will have base points that will not be excited. You may have rotational constraints to hold shafting and to remove plate and bar singularities, as the rotational components are not used in the DDAM excitation. No loads or other boundary conditions are needed for the analysis. As per 3010, you need to add operating loads to the shock loads at the conclusion of the analysis. Set up the model like any other modal analysis, with the exception of the SUPORT point. Mass and material density are required to obtain correct mode shapes. The modal analysis parameters are set up on the Subcase Options form, where you can select the number of desired modes, the lower frequency bound, and an upper frequency bound. The analysis uses a Lanczos extraction routine with mass normalization, and uses the default Lanczos debugging information level. You will not have control over these parameters in DDAM.

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Chapter 3: Running an Analysis 381 Solution Parameters

DDAM Solution Parameters

This subordinate form appears when the Solution Parameters button is selected on the Solution Type form when DDAM is selected. Use this form to generate a SOL 187 input file.

Parameter Name

Main Index

Description

Automatic Constraints

Indicates that an AUTOSPC entry is requested. MSC Nastran will automatically constrain model singularities.

Shell Normal Tol. Angle

Indicates that MSC Nastran will define grid point normals for a Faceted Shell Surface based on the Tolerance Angle. This data appears on a PARAM, SNORM entry.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Parameter Name

Description

Mass Calculation • Lumped • Coupled

Defines how the mass matrix is to be treated within MSC Nastran. This controls the setting of the COUPMASS parameter. This parameter can be set to either Coupled or Lumped. If set to Coupled, COUPMASS will be set to +1, otherwise, it will be set to -1.

Data Deck Echo • None • Sorted • Unsorted

Indicates how the data file entry images are to be printed in the MSC Nastran print file. This controls the setting used for the ECHO Case Control command. This parameter can have one of three settings: Sorted, Unsorted, or None.

Plate Rz Stiffness factor

Defines the in plane stiffness factor to be applied to shell elements. This defines the K6ROT parameter. This is an alternate method to suppress the grid point singularities and is intended primarily for geometric nonlinear analysis.

Maximum Printed Lines

Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.

Maximum Run Time

Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

Node id for Wt. Gener

Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

Default Initial Temperature Defines the Default Initial Temperature: TEMPD value for subcase entry TEMP(INITIAL)

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Default Load Temperature

Defines the Default Load Temperature: Sets the TEMPD value for the subcase entry TEMP(LOAD) subcase entry.

SUPPORT Node

Selects the point you have chosen for your base input. Note that this is a required choice with no default, and that you can only pick one node. If multiple nodes are entered in the data box, only the first one is used.

Results Output Format

On the Results Output Format form you choose which output formats you want to use with your solution type. For more details, please see Results Output Format, 405.

Chapter 3: Running an Analysis 383 Solution Parameters

Explicit Nonlinear This subordinate form appears when the Solution Parameters button is selected on the Solution Type form when Explicit Nonlinear is selected under Preferences: Analysis... . Use this form to generate a SOL 700 input file.

Parameter Name

Main Index

Description

Large Displacements

Use this to cause the large displacement formulation to be used.

Follower Forces

Use this to cause the forces to move (translate and rotate) with the model.

Prestress Option

Use this to cause the pre-stresses to be calculated.

Maximum Printed Lines

Limits the size of the MSC Nastran print file that will be generated. This defines the setting of the MAXLINES Case Control command.

Maximum Run Time

Limits the amount of CPU time expressed in CPU minutes that can be used by this run. This is used to prevent runaway jobs. This defines the setting of the TIME Executive Control statement.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Parameter Name

Description

Wt-Mass Conversion

Defines the conversion factor between weight and mass measures. This defines the setting of the WTMASS parameter.

Node ID for Wt. Gener.

Indicates the node ID that is to be used for the Grid Point Weight Generator. This is the GRDPNT parameter.

SOL 700 Default Settings Either Dytran or Ls-Dyna default settings can be used. • Sol700

Parameters...

• Resultts Output

Format...

Displays the Sol700 Parameters and Extra Data form that is used for specifing parameter values for such things as execution control, dynamic relaxation (entry DAMPGBL), general parameters, contact, and Eulerian parameters. See Sol700 Parameters Subform, 384 Use this to specify the types of files that are to be written for the SOL 700 analysis. For example, XDB (jobname.xdb) and Print (jobname.f06).See Results Output Format, 405

Sol700 Parameters Subform This subordinate form appears when Sol700 Parameters button is selected on the Solution Parameters form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as: • SOL700,101 - Linear Static • SOL700,106 - NonLinear Static • SOL700,109 - Direct Transient Response • SOL700,129 - NonLinear Transient

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Chapter 3: Running an Analysis 385 Solution Parameters

.

The supported parameters are shown in the following table: Parameter Name

Main Index

Description

Execution Control Parameters...

DYSTATIC, DYBLDTIM, DYINISTEP, DYTSTEPERODE, DYMINSTEP, DYMAXSTEP, DYSTEPFCTL, DYTERMNENDMAS, DYTSTEPDT2MS

Dynamic Relaxation...

This is for specifying the entries for the DAMPGBL Bulk Data entry. This is for defining parameter values for static analysis using dynamic relaxation for SOL 700 only.

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Parameter Name

Description

General Parameters...

DYLDKND, DYCOWPRD, DYCOWPRP, DYBULKL, DYHRGIHQ, DYRGQH, DYENERGYHGEN, DYSHELLFORM, DYSHTHICK, DYSHNIP

Contact Parameters...

DYCONSLSFAC, DYCONRWPNAL, DYCONPENOPT, DYCONTHKCHG, DYCONENMASS, DYCONECDT, DYCONIGNORE, DYCONSKIPTWG

Binary Output Database File Parameters...

DYBEAMIP, DYMAXINT, DYNEIPS, DYNINTSL, DYNEIPH, DYSTRFLG, DYSIGFLG, DYEPSFLG, DYRLTFLG, DYENGFLG, DYCMPFLG, DYIEVERP, DYDCOMP, DYSHGE, DYSTSSZ, DYN3THDT

Time History Output This is for specifying the type of output file (Binary, ASCII, Both), and the Request... Output Time Interval. Hourglass Setting...

See Hourglass Setting Subform, 386

Merge Rigid Mat...

See Merge Rigid Material Subform, 388

Dynamic Relaxation for Restart...

See Dynamic Relaxation for Restart Subform, 390

Damping Per Property...

See Damping Per Property Subform, 392

Rigid Body Switch and Merge...

See Rigid Body Switch and Merge Subform, 393

Eulerian Parameters...

See Eulerian Parameters Subform, 399

SPH Control Parameters...

See SPH Control Parameters Subform, 402

Hourglass Setting Subform This subordinate form appears when Hourglass Setting button is selected on the Sol700 Parameters and Extra Data form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as: • SOL700,101 - Linear Static • SOL700,106 - NonLinear Static • SOL700,109 - Direct Transient Response • SOL700,129 - NonLinear Transient

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Chapter 3: Running an Analysis 387 Solution Parameters

.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

The supported parameters are shown in the following table: Parameter Name

Description

Existing Hourglass Setting

List of previously created hourglass settings.

Hourglass Name

Specify the name.

Property Type

Specify either a Shell (2D) or Solid (3D) element type.

Control Type

Choose one of several types of controlling the hourglass effects. The choices are: 1) Standard LSDyna Viscous (Property Type = Shell or Solid), 2) Flanagan-Belytschko Viscous (Property Type = Shell or Solid), 3) Flan-Bely. Visc. + Vol. Integ. (exact volume integration for solid elements) (Property Type = Solid), 4) Flanagan-Belytschko Stiffness (Property Type = Shell or Solid), 5) Flan-Bely. Stiff. + Vol. Integ. (exact volume integration for solid elements) (Property Type = Solid), 6) Flanagan-Bindeman Stiffness (Property Type = Solid), 7) Fully Integrated Shell (Property Type = Shell). These entries are defined on the HGSUPPR Bulk Data entry in the MSC Nastran Quick Reference Guide.

Hourglass Coefficient

This entry is defined on the HGSUPPR Bulk Data entry in the MSC Nastran Quick Reference Guide.

Warping Hourglass Coeff.

This entry is defined on the HGSUPPR Bulk Data entry in the MSC Nastran Quick Reference Guide.

Bending Hourglass Coeff.

This entry is defined on the HGSUPPR Bulk Data entry in the MSC Nastran Quick Reference Guide.

Linear Bulk Visc. Coeff.

This entry is defined on the HGSUPPR Bulk Data entry in the MSC Nastran Quick Reference Guide.

Quadr. Bulk Visc. Coeff.

This entry is defined on the HGSUPPR Bulk Data entry in the MSC Nastran Quick Reference Guide.

Select Property Set

Select a previously created element property. For example, Properties > Create > 2D > Shell > Options: Explicit PSHELL1 > Input Properties... > Shell Formulations > HUGHES.

Add

Click Add after input all necessary data into the Hourglass Setting form to create an Existing Hourglass Setting.

Modify

Click Modify after input all changed data into the Hourglass Setting form to update an Existing Hourglass Setting. You must first select the particular Existing Hourglass Setting.

Merge Rigid Material Subform This subordinate form appears when Merge Rigid Mat button is selected on the Sol700 Parameters and Extra Data form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as:

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Chapter 3: Running an Analysis 389 Solution Parameters

• SOL700,101 - Linear Static • SOL700,106 - NonLinear Static • SOL700,109 - Direct Transient Response • SOL700,129 - NonLinear Transient

.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

The supported parameters are shown in the following table: Parameter Name

Description

Existing Merged Materials

List of previously merged MATRIG materials. MATRIG is an MSC Nastran Bulk Data entry for defining rigid body properties.

Merged Material Name

Specify the name of merged material to be created.

Select Material to be Merged into

Specify the name of an MATRIG material to merge other MATRIG materials into.

Select Materials to be Merged

Specify the names of MATRIG materials that are to be merged into the merged material whos name is specified under Merged Material Name.

Add

Click Add after input all necessary data into the Rigid Materials form to create an Existing Merged Materials.

Modify

Click Modify after input all changed data into the Rigid Materials form to update an Existing Merged Materials. You must first select the particular Existing Merged Materials.

Dynamic Relaxation for Restart Subform This subordinate form appears when Dynamic Relaxation for Restart button is selected on the Sol700 Parameters and Extra Data form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as: • SOL700,101 - Linear Static • SOL700,106 - NonLinear Static • SOL700,109 - Direct Transient Response • SOL700,129 - NonLinear Transient

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Chapter 3: Running an Analysis 391 Solution Parameters

The supported parameters are shown in the following table: Parameter Name

Main Index

Description

Relaxation

Use this to not use (None Active) or use (Activated Relaxation) relaxation in performing the simulation.

[Termination Time]

The time to stop the simulation. This is optional ([ ]).

Convergence Tolerance

Specify convergence tolerance.

Number of Iterations

Specify the maximum number of iterations.

Papadrakakis Auto Control

Click the checkbox to specify that convergence control is to be automatic using the Papadrakakis method.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Parameter Name

Description

Papadrakakis Convergence Tolerance

To use this it is necessary to not select Papadrakakis Auto Control.

Relaxation Factor

Specify the value of the Relaxation Factor.

Time step scale Factor

Specify the value of the Time step scale Factor.

Damping Per Property Subform This subordinate form appears when Damping Per Property button is selected on the Sol700 Parameters and Extra Data form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as: • SOL700,101 - Linear Static • SOL700,106 - NonLinear Static • SOL700,109 - Direct Transient Response • SOL700,129 - NonLinear Transient.

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Chapter 3: Running an Analysis 393 Solution Parameters

The supported parameters are shown in the following table: Parameter Name

Description

Damping Type

Select either Property (use property) or Stiffness (use Rayleigh damping).

System Damping Constant Table

Select a time dependent field under Time Dependent Field. This field will be multiplied by the Scalar Factor for Load Curve entry. The (X,Y,Z) Trans. Damping Forces and (X,Y,Z) Rot. Damping Moments entries (all of these form a 6 component load vector) are multiplied by the scaled time dependent field.

Time Dependent Field

Select a Field, with it being entered into the System Damping Constant Table list box. For example, select the field named damping_vs_time under Time Dependent Field. For System Damping Constant Table f:damping_vs_time appears.

Scale Factor for Load Curve

Specify the scale factor that will multiply the Time Dependent Field specified under System Damping Constant Table.

X Trans. Damping Forces

Scale factor for X translation damping forces, in the global coordinate system directions.

Y Trans. Damping Forces

Scale factor for Y translation damping forces, in the global coordinate system directions.

Z Trans. Damping Forces

Scale factor for Z translation damping forces, in the global coordinate system directions.

X Rot. Damping Moments

Scale factor for X rotation damping moments, in the global coordinate system directions.

Y Rot. Damping Moments

Scale factor for Y rotation damping moments, in the global coordinate system directions.

Z Rot. Damping Moments

Scale factor for Z rotation damping moments, in the global coordinate system directions.

Rayleigh Damping Coeff.

Specify the scalar coefficient (β) that the global stiffness matrix is multiplied by to obtain the Rayleigh damping matrix.

Rigid Body Switch and Merge Subform This subordinate form appears when Rigid Body Switch and Merge button is selected on the Sol700 Parameters and Extra Data form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as: • SOL700,101 - Linear Static • SOL700,106 - NonLinear Static • SOL700,109 - Direct Transient Response • SOL700,129 - NonLinear Transient

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.

The supported parameters are shown in the following table: Parameter Name

Main Index

Description

Option

Only option is At Start (D2R0000).

Existing Merged Properties

List of deformable body and rigid body properties that have already been merged.

Merged Body Name

Specify the name of the Existing Merged Properties entry to be created.

Deformable Property

Select an entry under Deformable Property

Master Rigid Property

Select an entry under Master Rigid Property

Add

Click Add to create an entry under Existing Merged Properties.

Chapter 3: Running an Analysis 395 Solution Parameters

Parameter Name

Description

Modify

Click Modify to save the changed selections under Deformable Property and Master Rigid Property to update an Existing Merged Properties. You must first select the particular Existing Merged Properties.

Define Set of Parts to be Switched

See Define Set of Parts to be Switched Subform, 396

Define Inertial See Define Inertial Properties of Rigid Body Subform, 398 Properties of Rigid Body

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Define Set of Parts to be Switched Subform This subordinate form appears when Define Set of Parts to be Switched button is selected on the Rigid or Deformable Parts Switching form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as: • SOL700,101 - Linear Static • SOL700,106 - NonLinear Static • SOL700,109 - Direct Transient Response • SOL700,129 - NonLinear Transient.

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Chapter 3: Running an Analysis 397 Solution Parameters

The supported parameters are shown in the following table: Parameter Name

Description

Option

Only option is At Stage (D2RAUTO).

Existing Merged Properties

List of deformable body and rigid body properties that have already been merged.

Merged Body Name

Specify the name of the Existing Merged Properties entry to be created.

Deformable Property

Select an entry under Deformable Property.

Master Rigid Property

Select an entry under Master Rigid Property. For example, a 2D Shell Element Property created using an Isotropic (SOL 700) Rigid MATRIG material.

Add

Click Add to create an entry under Existing Merged Properties.

Modify

Click Modify to save the changed selections under Deformable Property and Master Rigid Property to update an Existing Merged Properties. You must first select the particular Existing Merged Properties.

Starting Switch Time Specify the time to switch the deformable and rigid properties. Ending Switch Time

Specify the time to terminate the switching of the deformable and rigid properties.

Delay Period

Specify the time delay (τ) for switching.

Rigid Wall/Contact Surf Number

Specify the surface numbers for rigid walls/surfaces that are to contact.

Related Switch Set Max. Permited Time Specify the maximum time step. Step Size

Main Index

Number of Deformable Parts to Rigid

Specify the number of deformable parts that will be switched to rigid parts.

Number of Rigid Parts to Deformable

Specify the number of rigid parts that will be switched to deformable parts.

Activation Code Switch

Select one of the five flags, 1) EQ.0, 2) EQ.1, 3) EQ.2, 4) EQ.3, or 5) EQ.4.

Pair of Related Switches

Select one of the three flags, 1) EQ.0, 2) EQ.1, 3) EQ.-1.

Nodal Rigid Body Activation Flag

Select one of the three flags, 1) EQ.0, 2) EQ.1, 3) EQ.2.

Nodal Constraint Activation Flag

Select one of the three flags, 1) EQ.0, 2) EQ.1, 3) EQ.2.

Rigid Wall Activation Flag

Select one of the three flags, 1) EQ.0, 2) EQ.1, 3) EQ.2.

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Define Inertial Properties of Rigid Body Subform This subordinate form appears when Define Inertial Properties of Rigid Body button is selected on the Rigid or Deformable Parts Switching form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as: • SOL700,101 - Linear Static • SOL700,106 - NonLinear Static • SOL700,109 - Direct Transient Response • SOL700,129 - NonLinear Transient.

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Chapter 3: Running an Analysis 399 Solution Parameters

The supported parameters are shown in the following table: Parameter Name

Description

Option

Only option is New Rigid Props. (D2RINNER).

Master Rigid Property

Select a Master Rigid Property. For example, a 2D Shell Element Property created using an Isotropic (SOL 700) Rigid MATRIG material.

X Coord of Center of X coordinate of center of mass. Mass Y Coord of Center of Y coordinate of center of mass. Mass Z Coord of Center of Z coordinate of center of mass. Mass Translational Mass

Scalar mass value for translation, not rotation.

XX Comp. of Inertia Tensor (IXX)

XX (1,1) component of inertia tensor matrix.

XY Comp. of Inertia Tensor (IXY)

XY (1,2) component of inertia tensor matrix.

XZComp. of Inertia Tensor (IXZ)

XZ (1,3) component of inertia tensor matrix.

YY Comp. of Inertia Tensor (IYY)

YY (2,2) component of inertia tensor matrix.

YZ Comp. of Inertia Tensor (IYZ)

YZ (2,3) component of inertia tensor matrix.

ZZ Comp. of Inertia Tensor (IZZ)

ZZ (3,3) component of inertia tensor matrix.

Eulerian Parameters Subform This subordinate form appears when Eulerian Parameters button is selected on the Sol700 Parameters and Extra Data form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as: • SOL700,101 - Linear Static • SOL700,106 - NonLinear Static • SOL700,109 - Direct Transient Response • SOL700,129 - NonLinear Transient

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.

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Chapter 3: Running an Analysis 401 Solution Parameters

The supported parameters are shown in the following table: Parameter Name

Description

Euler Boundary Treatment

There are three choices, 1) Default, 2) Extrapolate (extrapolate structural mesh pressure to Euler elements at solid/fluid boundary), or 3) Element (solid/fluid boundary Euler element pressure equals the structural element pressure at the solid/fluid boundary).

Multi-Mat. Trans. Scheme

There are three choices, 1) Default (Impulse), 2) Average (face (surface) velocity is averaged simply), or 3) Impulse (face (surface) velocity is impulse weighted).

Material Failure Option

There are three choices, 1) Default (No Fail), 2) Fail (activates transport of fail fraction and thereby keeps track of material that has failed), or 3) No Fail (failed Euler material can support shear stress again as soon as new material enters the Euler element).

Multi-Material Array Size

The multi-material Eulerian elements use an overflow array to store their material data. This array can hold “Multi-Material Array Size” times the number of Eulerian elements. If more the 10% of the Eulerian elements have more than one material, the value of “Multi-Material Array Size” must be increased.

Initial Condition Accuracy

A parameter value used to specify the accuracy of the initial conditions in Eulerian elements, when using the geometric shape definition. The parameter value is specified in the input file using PARAM, MICRO, value.

Mimimum Velocity

A parameter value used to specify the minimum velocity. If a calculated velocity is less than this, it is set to zero (0). It is mainly used to eliminate harmless small values. The parameter value is specified in the input file using PARAM, VELCUT, value.

Maximum Velocity

Specify the maximum velocity for Eulerian and Lagrangian meshes. Although it is not usually necessary to limit the velocity in Eulerian meshes, there are occasions in regions of near-vacuous flow where using this can be an advantage. The same thing applies to Lagrangian meshes, where there is contact. The parameter value is specified in the input file using PARAM, VELMAX, value, YES/NO. Default is 1.0e10, YES. See the next row for information on what YES/NO means.

Small Mass Removal Because very high velocities occur mostly in Eulerian elements with very small mass, the mass in these elements may need to be removed for the analysis to be stable. The above parameter (PARAM, VELMAX) is used to specify whether or not to eliminate small masses. YES = eliminate the mass for Eulerian elements for which the velocity is > the value of VELMAX. NO = do not eliminate the mass for Eulerian elements for which the velocity is > the value of VELMAX. Default = YES. Universal Gas Constant

Main Index

Specify the value of the universal gas constant. The parameter value is specified in the input file using PARAM, UGASC, value.

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Parameter Name

Description

Single Material Elements

Specify the minimum density of single material Eulerian elements. For arbitrary Lagrange-Euler (ALE) coupling, Eulerian single material elements with strength cannot be used.

Single Mats. with Strength

Specify the minimum density of single material Eulerian elements with strength. For arbitrary Lagrange-Euler (ALE) coupling, Eulerian single material elements with strength cannot be used.

Multi-Material Elements

Specify the minimum density of multi-material Eulerian elements.

Roe Solver Scheme

Specify whether or not to use the Roe solver. The Roe solver accounts for momentum exchange between Lagrange (structure) and Eulerian material.

Spatial Accuracy

There are two schemes that can be used. They are, 1) 1st Order (left and right state variables are taken as the values the state variables have at the left- and the right-element center), or 2) 2nd Order (left- and right-state variable values at a face by including the left-left and the right-right element).

Time Integration Scheme

There are two schemes that can be used. They are, 1) 1st Order, or 2) 2nd Order (three-stage time integration scheme).

SPH Control Parameters Subform This subordinate form appears when SPH Control Parameters (SPH refers to smooth “particle hydrodynamics”) button is selected on the Sol700 Parameters and Extra Data form of either Explicit Nonlinear or other structural Solution Type where Sol700 is available such as: • SOL700,101 - Linear Static • SOL700,106 - NonLinear Static • SOL700,109 - Direct Transient Response • SOL700,129 - NonLinear Transient

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Chapter 3: Running an Analysis 403 Solution Parameters

.

The supported parameters are shown in the following table: Parameter Name

Main Index

Description

Number of Cycles

Specify the number of cycles between particle sorting.

Death Time

Specify the time when SPH calculations are to be stopped.

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Parameter Name

Description

Initial Number of Neighbors

Specify the initial number of neighbors per particle. This parameter is for specifying how much memory is to be allocated for arrays during initialization. If the value is positive, the memory will be dynamically allocated. If the value is negative, the memory allocation will be static (constant). During the calculation only the closest SPH elements will be considered as neighbors. Using this option can avoid memory allocation problems.

Particle Approx. Theory

There are six theories to choose from, 1) Renormalization (approximation), 2) Symmetric (formulation), 3) Sym. Renormalization (symmetric renormalization approximation), 4) Tensor (tensor formulation), 5) Fluid Particle (fluid particle approximation), 6) Fluid Particle Renorm (fluid particle with renormalization approximation).

Start Time

Specify the time to begin particle approximation.

Maximum Velocity

Maximum velocity for the SPH particles. Particles whos velocity > this value are deactivated.

Computation of Approx.

Select one of the following for two different SPH parts, 1) Particle Approximation (approximation is calculated), or 2) No Particle Approximation (approximation is not calculated; two different SPH materials cannot interact with each other, and penetration is allowed).

Intergration Type

Select 1) 0 ( d ( h ( t ) ) = 1--- h ( t )div ( v ) ), or 2) 1 dt

d

( d ( h ( t ) ) = 1--- h ( t ) ( div ( v ) ) 1 ⁄ 3 ), for time integrating to obtain the dt

d

smoothing length.

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Smoothing Length Comput.

Select 1) Bucket (sort based on algorithm; very fast), or 2) Global (computation for all the model particles ). This is done during initialization.

Box Type

Select either 1) Fixed (the box remains fixed in space), or 2) Moving (the user specifies two corners of the box and a the time dependent Field to describe the motion of the two corners). As long as a given SPH particle is in a box, the SPH calculation for the particle is performed for the box. If the particle leaves the box it was inside, it is deactivated.

Select Box

Select the name of a box under Select Box. A box must have been previously created under Loads/BCs: Create / Box Definition / Nodal.

Tail Vector

Specify a vector, , that defines the minimum coordinates of the box (coordinates of the corner of the box at the minimum location).

Head Vector

Specify a vector, , that defines the maximum coordinates of the box (coordinates of the corner of the box at the maximum location).

Chapter 3: Running an Analysis 405 Solution Parameters

Parameter Name

Description

Motion Vs Time Data

Specify the time dependent Field that defines the motion of the two corners of the box.

Vel./Disp. Flag

Specify whether the time dependent Field is a Velocity or Displacement field.

Coord. System

Specify the coordinate system that the Tail and Head Vectors are defined in.

Results Output Format With the results output format form you can choose which output formats you want to use with each solution sequence. The appropriate defaults are set for each solution type. These defaults can be changed or set in the settings.pcl file.

A new variable has been added to the settings.pcl file for results output format defaults per SOL Parameter Name

Main Index

Description

• OP2

Specifies output of data to a MSC Nastran OUTPUT2 file (*.op2). This places a PARAM,POST,-1 in the input file if MSC Nastran version is 2012 or less. For MSC Nastran 2013 or higher, a PARAM,POST,1 is written. The PARAM, POST integer value can be overridden by setting the environment variable PARAM_POST_OP2 to any integer number or using the settings.pcl file setting: pref_env_set_integer( “PARAM_POST_OP2”,). Note that this only works with the OP2 toggle ON.

• XDB

Specifies output of data to a MSC.Access database (*.xdb). This will place a PARAM,POST,0 in the input file.

• Print

Specifies output of data to a MSC Nastran print file (*.f06).

• Punch

Specifies output of data to a MSC Nastran punch file (*.pch).

• MASTER Only

When ON, only a .master file is written.

• MASTER/DBALL

When ON, both a .master file and a .dball file are written.

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Parameter Name • HDF5

(Compressed) (No Rot.DOFs)

• XDB Buffer Size

Description When ON, requests an HDF5 results database file be written. This is done by including a MDLPRM,HDF5,0 (or 1 if Compressed is ON) to the input deck. If no rotational degree-of-freedom results are to be written to the HDF5 file, turn the No Rot.DOFs toggle ON. Otherwise both translational and rotational DOF results are written to the HDF5 database. This sets the MDLPRM,H5NORDOF,1 entry. For the XDB results file, defines the buffer size used for accessing results.

OUTPUT2 Requests Specifies type of OUTPUT2 commands. • P3 Built In - signals the use of MSC Nastran internal OUTPUT2

commands geared toward Patran. These commands are also appropriate for PATRAN 2. The “P3 Built In” option is appropriate only for Database Runs, see Solution Parameters, 312. If Database Run has been deselected, this option will be set internally to “Alter File”. • Alter File - specifies the use of an external alter file found on the Patran

file path and following the “msc_v#_sol#.alt” naming convention. See Files, 650 for more details. • CADA-X Alter - specifies the use of an LMS CADA-X specific alter file

that is identical to the “Alter File” but with an additional “.lms” extension, for example, “msc_v67_sol103.alt.lms”. • P2 Built In - specifies use of MSC Nastran internal OUTPUT2 commands

geared toward PATRAN 2. OUTPUT2 Format

Specifies format of the MSC Nastran OUTPUT2 (*.op2) files. Use “Text” format when the resulting OUTPUT2 file must be transported between heterogeneous computer platforms.

sequence: NASTRAN_nnn_DATA_OUTPUT OP2+PUNCH Where nnn is the solution sequence 101, 400 etc... and OP2+XDB+PRINT+PUNCH+MASTER +DBALL are the options. This variable is only read from the settings.pcl file when opening a new database, creating a new job or changing the solution sequence of an existing job. Otherwise the results output settings are retrieved from the database for an existing job. Note that these variables must be added to the settings.pcl file by the user and if they do not exist, a standard default is used. Also note that OP2 and XDB are mutually exclusive and both cannot be specified at the same time. The same is true for MASTER Only and MASTER/DBALL. The settings.pcl file may have one of these variables for each SOL sequence defined in Patran (>100).

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Chapter 3: Running an Analysis 407 Solution Parameters

ADAMS Preparation This form is used when you want to prepare a database for an Adams job.

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Patran Interface to MSC Nastran Preference Guide Solution Parameters

Parameter Name ADAMS Output

Description • MNF Only • Full Run + MNF

Units

• Mass - Your options are: Kilogram, Pound-Mass, Slug, Gram, Ounce-

Mass, Kilo-Pound-Mass, Megagram • Force - Newton, Pounds-Force, Ounce-Force, Dyne, Kilo-Newton, Kilo-

Pound-Force • Length - Millimeter, Centimeter, Meter, Kilometer, Inch, Foot, Mile • Time - Millisecond, Second, Minute, Hour

Craig-Bampton Modes Bounds

• Lower Bound • Upper Bound

Num. Shapes to Adams ADAMS Debug Print Strip Face Create .out(OP2 file) for MSC Fatigue Mass Options

• Partial • Constant File • Full • None

Output Requests Transfer Groups to ADAMS

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Chapter 3: Running an Analysis 409 Select Superelements

3.6

Select Superelements The superelements created in the FEM menu are displayed in the form below. The superelements for a subcase are selected by highlighting the name in the listbox. Default button unselects all the superelements. If Write PART Superelements toggle is ON in the Translation Parameters, 298 form, then BEGIN BULK SUPER=id sections are written to the input file to define the superelements, otherwise if this is OFF, SESET entries are used. In addition to selecting the superelement, you can specify the superelement tree definition. This tell the analysis which superelement are upstream of others and thus, not directly connected to the residual structure or superelement zero (SE0). To define an upstream SE relative to its downstream SE, use the form shown below to fill out the spreadsheet. Put focus in the Downstream databox, select a superelement from the list, then select the upstream from the list and press Add. This adds a row to the spreadsheet. Repeat this for every upstream element you need to define. Clicking on a row in the spreadsheet and clicking Remove will remove the defintion. Downstream SEs can only appear in the speadsheet once. This writes the SETREE entry.

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SE5

SE6 SE4

SE3

SE1

SE0

Main Index

SE2 In this example, SE1, SE2, & SE3 are upstream of the residual. This is not necessary to define in the SE tree. However SE4 is upstream of SE3 and SE5 & SE6 are upstream of SE4. These should be defined in the tree.

Chapter 3: Running an Analysis 411 Subcases

3.7

Subcases This form appears when the Subcases... button is selected on the Analysis form. The subcase is the MSC Nastran mechanism for associating loads and boundary conditions, output requests, and various other parameters to be used during part of a complete run. The Patran MSC Nastran interface automatically associates default parameters and output requests with each Patran load case to create a subcase with the same name as the load case. You can access the Subcase Parameters... and Output Requests... forms to view or modify these defaults.

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Parameter Name

Description

Action

Options are Create, Delete, and Global Data.

Available Subcases

Displays all the available subcases associated with the current Solution Sequence.

Subcase Name

The subcase name that is being created or modified is displayed in this databox. It can be typed in or picked from the Available Subcases listbox.

Available Load Cases

Displays all the available loadcases in the current database. Only one loadcase can be selected per subcase. For Normal Modes and Complex Eigenvalue solution types, free-free runs can be generated by using an empty load case.

Deleting Subcases To delete subcases, select Subcases from the Analysis form, and set the Action to Delete.

Parameter Name

Main Index

Description

Select Subcases

Select the subcase(s) to delete.

Apply

Apply to delete the selected subcases.

Chapter 3: Running an Analysis 413 Subcases

Editing Subcases To edit global data for subcases, select Subcases from the Analysis form, and set the Action to Global Data. The following form appears.

Parameter Name

Main Index

Description

Select Subcases

Select Subcase(s) to edit associated data.

Output Requests...

Use Output Requests... to edit the output requests associated with the selected subcases. The Edit Output Request form appears. See Edit Output Requests Form, 491.

Apply & Cancel

Apply changes the output requests for all selected subcases. Cancel closes the form without changes.

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3.8

Subcase Parameters The subcase parameters represent the settings in MSC Nastran Case Control that take effect within a subcase and do not affect the analysis in other subcases. Currently, the following solution sequences have subcase parameters associated with them. Solution Sequences

Other Conditions

Linear Static Subcase Parameters, 414

SOL 101

Nonlinear Static Subcase Parameters, 416

Model has p-elements and utilizes Version 68

Selects the subcase to participate in the error analysis calculations in an adaptive analysis. By default the subcase participates in the error analysis.

None

Selects nonlinear static iteration parameters.

None

Selects nonlinear transient iteration parameters.

Version 68

Selects real eigenvalue extraction parameters.

SOL 106, 66 Nonlinear Transient Subcase Parameters, 419

Description

SOL 129, 99 Normal Modes Subcase Parameters, 421

SOL 103 Implicit Nonlinear Subcase Parameters, 435 DDAM Subcase Parameters, 468 Explicit Nonlinear Subcase Parameters, 470

Linear Static Subcase Parameters This form is available for solution sequence 101 for MSC.Nastran Version 68 and for models that contain p-elements. The form allows the inclusion of subcases in the error analysis. This toggle sets the ADACT Case Control command.

Parameter Name

Main Index

Description

Perform Error Analysis

This toggle allows for inclusion of subcases in the error analysis and sets the ADACT Case Control command.

Default Load Temperature

Creates a TEMPD entry for the specified Subcase and is called out using TEMP case control. This defines temperatures on all grids(modes) that do not have specific temperature LBCs defined.

Enable Rotor Dynamics

Used to turn rotor dynamics on for the linear static Subcase. If enabled, the Rotor Speed Form becomes accessible to specify rotor speed, as shown below.

Chapter 3: Running an Analysis 415 Subcase Parameters

Parameter Name

Description

Use Contact Table

Toggle button to enable or disable the use of Contact Table.

Load Increment Params…

For SOL 101 jobs involving contact, the fixed number of increments can be specified on this form. Only fixed load incrementation is allows for static SOL 101 jobs with contact. Please see Load Increment Parameters, Load Increment Parameters, 443 for more information. The number of increments is written to the NLSTEP entry for jobs with contact.

Iteration Parameters For SOL 101 jobs involving contact, certain iteration parameters can be specified or changed to help with convergence. In general, the default values should be used. Please see Iteration Parameters, Iteration Parameters, 451 for more information. Parameters set on this form are written to the NLSTEP entry.

Main Index

Contact Table

This subordinate form allows for the ability to specify which contact bodies are allowed to come into contact which other bodies or themselves (self contact), including glued contact. See Contact Table, 456 for more information.

Solver/Options

This subordinate form allows for the ability to specify the Nastran solver to be used for the Subcase being set up. See Solvers/options Contact Table, 456 for more information.

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Nonlinear Static Subcase Parameters This subordinate form appears when the Subcase Parameters button is selected on the Subcases form when the solution type is Nonlinear Static. This form allows the definition of the parameters that control the interation criteria for a Nonlinear Static analysis. All of the data is part of the NLPARM Bulk Data entry. If Arc-Length Method is selected, additional data for the NLPCI Bulk Data entry is generated.

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Chapter 3: Running an Analysis 417 Subcase Parameters

This is a list of data input available for defining the Static Nonlinear Iterations.

Parameter Name

Description

Number of Load Increments Defines the number of increments to be used to apply the full load. This is the NINC field. Matrix Update Method

Defines what method to use to control the stiffness. Matrix updates as the load is incrementally applied. This parameter can have one of three settings: Automatic, Semi-Automatic, or Controlled Iter. This defines the setting of the KMETHOD field.

Number of Iterations per Update

Defines the number of iterations to be used after each matrix update. This is the KSTEP field.

llowable Iterations per Increment

Defines the number of iterations to be used after each matrix update. This is the KSTEP field.

Displacement Error

Indicates whether a displacement convergence criteria should be used. If Displacement Error is selected, the Displacement Tolerance field becomes active. This value defines the tolerance on displacements. The displacement tolerance must be met between iterations to define convergence. If Displacement Error is selected, a U is entered in the CONV field. The Displacement Tolerance is the EPSU field.

Displacement Tolerance

Load Error Load Tolerance

Work Error Work Tolerance

Indicates whether a load convergence criteria should be used. If Load Error is selected, the Load Tolerance field becomes active. This value defines the tolerance on load equilibrium. The load equilibrium tolerance must be met between iterations to define convergence. If Load Error is selected, a P is entered in the CONV field. Load Tolerance is the EPSP field. Indicates whether a work convergence criteria should be used. If Work Error is selected, the Work Tolerance field becomes active. This value defines the tolerance on work error. The work tolerance must be met between iterations to define convergence. If Work Error is selected, a W is entered in the CONV field. Work Tolerance is the EPSW field.

Arc-Length Method...

Opens a subordinate form to activate the Arc-Length Method which is turned OFF by default. The Arc-Length Method is used to explore post-buckling paths.

Normal Modes

Activates a normal mode analysis of the prestressed system at the end of the subcase.

Buckling

Activates a buckling analysis at the end of the subcase.

Default Load Temperatures

Creates TEMPD entry for specified Subcase and is called out using TEMP case control. This defines temperatures on all grids(modes) that do not have specific temperature LBCs defined

Solvers/Options...

See Solvers/Options, 465 for more information.

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Patran Interface to MSC Nastran Preference Guide Subcase Parameters

Arc-Length Method Parameters This subordinate form appears when the Arc-Length Method button is selected on the Subcase Parameters form. This form allows the definition of parameters that control the Arc-Length Method. All of the data is part of the NLPCI Bulk Data entry.

Parameter Name Constraint type

Description Defines the type of Arc-Length Method: CRIS = Crisfield method (default) RIKS = Riks method MRIKS = modified Riks method

Min. Adjust. ratio (MINALR)

Minimum allowable arc-length adjustment ratio between increments for the adaptive arc-length method 0.0≤MINALR≤1.0.

Max. Adjust. ratio (MAXALR)

Maximum allowable arc-length adjustment ratio between increments for the adaptive arc-length method MAXALR≥1.0.

Scale Factor (W)

Scale factor w for arc-length criteria:

w=0, displacement control w>0, combined load and displacements control w»1, load control

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Chapter 3: Running an Analysis 419 Subcase Parameters

Parameter Name

Description

Convergence Iterations

Desired number of iterations for convergence to be used for the adaptive arc-length adjustments. This is the DESITER field

Max. Controlled Incremenr Steps

Maximum number of controlled increment steps allowed within the subcase. This is the MXINC field.

Nonlinear Transient Subcase Parameters This subordinate form appears when the Subcase Parameters button is selected on the Subcases form when the solution type is Nonlinear Transient. All of the data is part of the TSTEPNL Bulk Data entry.

This is a list of data input available for defining the Transient Nonlinear Iterations. Parameter Name

Main Index

Description

Ending Time

Defines the Ending Time for the subcase.

Number of Time Steps

Defines the Number of Time Steps for the subcase.

Matrix Update Method

Defines what method to use to control the stiffness. The Mass matrix updates as the load is incrementally applied. This parameter can have one of three settings: Adaptive, Automatic, or Time Step. This is the METHOD field.

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Parameter Name

Main Index

Description

Number of Time Steps per Update

Defines the number of time steps to be used in each matrix update. This can only be set if Matrix Update Method is set to Time Step. This is the NDT field.

Number of Bisections per Update

Defines the maximum number of time step bisections to be used in each matrix update. This can only be set if Matrix Update Method is set to Adaptive. This is the MAXBIS field.

Allowable Iterations per Time Steps

Defines the limit for the number of iterations that can be done in any given increment. This is the MAXITER field.

Chapter 3: Running an Analysis 421 Subcase Parameters

Normal Modes Subcase Parameters The Normal Modes subcase parameters form is available only for Solution 106 for MSC.Nastran Version 70.7. Use this form to create either EIGR or EIGRL Bulk Data entries.

Main Index

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Patran Interface to MSC Nastran Preference Guide Subcase Parameters

This is a list of data input available for defining the Real Eigenvalue Extraction. Parameter Name

Main Index

Description

Extraction Method

Defines the method to use to extract the real eigenvalues. This parameter can be set to any one of the following: Lanczos, Automatic Givens, Automatic Householder, Modified Givens, Modified Householder, Givens, Householder, Enhanced Inverse Power, or Inverse Power. If this is set to Lanczos, this indicates that an EIGRL Bulk Data entry should be created. Otherwise, this defines the setting of the METHOD field on the EIGR Bulk Data entry.

Frequency Range of Interest

Defines the lower and upper limits to the range of frequencies to be examined. These are the F1 and F2 fields on the EIGR Bulk Data entry or the V1 and V2 fields on the EIGRL Bulk Data entry.

Number of Desired Roots

Indicates the limit to how many eigenvalues to be computed. This is the ND field on the EIGR or EIGRL Bulk Data entries.

Diagnostic Output Level

Defines the level of desired output. This can take any integer value between 0 and 3. This parameter can only be specified if Extraction Method is set to Lanczos. This is the MSGLVL field on the EIGRL Bulk Data entry.

Normalization Method

Indicates what type of eigenvalue normalization is to be done. This parameter can take one of three settings: Mass, Maximum, or Point. This parameter cannot be specified if Extraction Method is set to Lanczos. Defines the setting of the NORM field on the EIGR Bulk Data entry.

Normalization Point

Defines the point to be used in the normalization. This can only be selected if Normalization Method is set to Point. This parameter cannot be specified if Extraction Method is set to Lanczos. This is the G field on the EIGR Bulk Data entry.

Normalization Component

Defines the degree-of-freedom component at the Normalization Point to be used. This can only be selected if Normalization Method is set to Point. This parameter cannot be specified if Extraction Method is set to Lanczos. This is the C field on the EIGR Bulk Data entry.

Number of Modes in Error Analysis

Indicates how many modes will participate in the error analysis when the model contains p-elements. This data sets the ADACT Case Control command.

Chapter 3: Running an Analysis 423 Subcase Parameters

Parameter Name

Description

Default Load Temperatures

Creates TEMPD entry for specified Subcase and is called out using TEMP case control. This defines temperatures on all grids(modes) that do not have specific temperature LBCs defined

Use Contact Table

Toggle button to enable or disable the use of Contact Table. See Contact Table, 456 for more information.

Complex Eigenvalue Subcase Parameters This subordinate form appears when you select Subcase Parameters button on the Subcases form and the solution type is Complex Eigenvalue.

Parameter Name

Main Index

Description

Enable Rotor Dynamics

Used to turn rotor dynamics on for the complex eigenvalue subcase. Rotor dynamics is disabled by default.

Specify Spinning Properties

If enabled, the “Specify Spin Properties” button will be enabled, and can be selected to display the Spinning Properties Form.

Use Contact Table

Toggle button to enable or disable the use of Contact Table.

Contact Table

See Contact Table, 456 for more information.

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Patran Interface to MSC Nastran Preference Guide Subcase Parameters

Parameter Name Options

Description Synchronous (default) or Asynchronous Defines the SYNCFLG field of the MSC Nastran RGYRO Bulk Data entry.

Main Index

Reference Rotor

The reference rotor for the subcase. This drives the RGYRO Case Control and Bulk Data (REFROTR field) in the MSC Nastran Bulk Data file.

Speed Unit

Relative speeds to the reference rotor. These values define the SPDUNIT, SPDHIGH, and SPDLOW fields of the MSC Nastran RGYRO Bulk Data entry. The SPEED value is left lank.

Speed High / Speed Low

For Asynchronous analyses, a single Speed databox is presented, defining SPEED field, while SPDHIGH and SPDLOW are left blank.

Chapter 3: Running an Analysis 425 Subcase Parameters

Transient Response Subcase Parameters This subordinate form appears when you select Subcase Parameters button on the Subcases form and the solution type is Transient Response. Use this form to specify the time step interval and duration for a transient response analysis. All of the data is part of the TSTEP Bulk Data entry. Direct Transient and Modal Transient Solutions

This is the subcase parameters form for the Direct Transient and Modal Transient solution.

Parameter Name

Main Index

Description

DEFINE TIME STEPS

Use this button to define your TSTEP entry.

Modal Damping

Modal Damping is only shown if you select Modal Damping formulation from the Solution Type form.

DEFINE MODAL DAMPING...

Use this button to define your TABDMP1 entry. You must enter at least one value of frequency and damping on the spreadsheet for damping to occur.

Use Contact Table

Toggle button to enable or disable the use of Contact Table.

Contact Table

See Contact Table, 456 for more information.

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Patran Interface to MSC Nastran Preference Guide Subcase Parameters

Define Time Step

Use this form to define the time steps in a linear table. Values of Delta-T (Time Increment) must be positive. See MSC Nastran Quick Reference Guide TSTEP for more information.

Parameter Name No. of Time Steps / Delta-T

Description No. of Time Steps and Delta-T determine the solution points in time. The skip factor defines which of the solution points you wish to perform results processing on. A skip factor of 1 indicates every time step, 2 indicates every other solution step, etc. Total solution time accumulates in order of entry. For the example shown, MSC Nastran will calculate output at 100 time steps ranging between 1. and 100.

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Skip Factor

The "Skip Factor" column is optional. If the column is empty, MSC Nastran assumes the Skip Factor is 1.

Add Row

"Add Row" adds a row after the selected row. To insert a row at the beginning of the table, select click on the row label and select "Add Row".

Chapter 3: Running an Analysis 427 Subcase Parameters

Define Damping

Use this form to define Damping in a linear table. Values of frequency must be positive. Discontinuities (same value of frequency, different value of damping) are allowed at all locations except the first and last entries in the table. See MSC Nastran Quick Reference Guide TABDMP1 for more information. Modal Damping does not allow a discontinuity to exist as either the first or last entries in the modal damping data. This will cause an error in MSC Nastran. It is strongly recommended that you do not create such scenario. If the first and second frequencies (two lowest frequencies) are the same value, a warning will be issued, even if the damping value for those frequencies are the same. If the last and second to last frequencies (two highest frequencies) are the same value, a warning will be issued, even if the damping value for those frequencies are the same.

Parameter Name Add Row

Main Index

Description "Add Row" adds a row after the selected row. To insert a row at the beginning of the table, click on the row label and select "Add Row".

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Frequency Response Subcase Parameters This subordinate form appears when you select the Subcase Parameters button on the Subcases form and the solution type is Frequency Response. Use this form to specify the frequencies for a frequency response analysis. All of the data is part of a FREQi Bulk Data entry. Frequency Solution

This is the Frequency Subcase Parameter Form.

Parameter Name

Main Index

Description

Define Frequencies

Use this button to define FREQ,FREQ1,FREQ2, FREQ3, FREQ4 entries.

Enable Rotor Dynamics / Specify Spinning Properties

Used to turn rotor dynamics on for the complex eigenvalue subcase. If enabled, the “Specify Spin Properties” button will be enabled, and can be selected to display the Spinning Properties Form, below.Rotor dynamics is disabled by default.

Chapter 3: Running an Analysis 429 Subcase Parameters

Parameter Name

Description

Use Contact Table

Toggle button to enable or disable the use of Contact Table.

Contact Table

See Contact Table, 474 for more information.

Solver / Options

See Solvers/Options, 465 for more information.

Use this form to create FREQi entries.

Parameter Name Add Row

Description "Add Row" adds a row after the selected row. To insert a row at the beginning of the table, click on the row label and select "Add Row".

The driving column on this form is the Increment type.

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Direct Frequency

When the Increment type is...

Patran...

Discrete

Creates a FREQ entry where Start Freq is the frequency value. Multiple Discrete rows will be written to the same FREQ entry. End Freq. and No. Incr. columns are not used.

Linear

Creates a FREQ1 entry. The Start Freq. will be the first frequency and the End Freq. and No. Increments will have a linear progression in between.

Logarithmic

Creates a FREQ2. Same as Linear, except it will have a logarithmic progression.

Modal Frequency

When the Increment type is...

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Patran...

Discrete

Creates a FREQ entry where Start Freq is the frequency value. Multiple Discrete rows will be written to the same FREQ entry. End Freq, No. Incr. and Cluster/Spread columns are not used.

Linear

Creates a FREQ1 entry. The Start Freq. will be the first frequency and the End Freq. and No. Increments will have a linear progression in between. The Cluster/Spread column is not used.

Logarithmic

Creates a FREQ2. Same as Linear, except it will have a logarithmic progression.

Lin. Cluster

Creates a FREQ3 with type set to LINEAR. This results in a linear distribution of solution frequencies between each successive pair of natural modes in the specified frequency interval. The Cluster value, which has a default of 1.0 is used to bias the linear distribution of solution frequencies. A smaller cluster value has a closer spacing towards the center, CLUSTER greater than 1.0 has a closer spacing at the ends of the frequency range.

Log. Cluster

Same as Lin. Cluster except that a logarithmic interpolation is used between the start and end frequencies.

Chapter 3: Running an Analysis 431 Subcase Parameters

When the Increment type is...

Patran...

Lin. Spread

Creates a FREQ4 entry. The default value of spread is 0.1. The spread is a fractional amount specified for each mode. With a spread of 0.3 and No. Incr. of 21, there will be 21 evenly spaced frequencies between 0.7*FN and 1.3*FN, where FN a natural frequency, for all natural frequencies between the specified “Start Freq” and “End Freq” values.

Fractional Spread

Creates a FREQ5 entry. Enter the Start Frequency and End Frequency. These are the lower and upper bound for the excitation (solution) frequency domain, respectively. It is desired to obtain a set of excitation frequencies around and at each natural frequency, obtained previously from the corresponding modal analysis for this simulation. This is done by providing a list of fractions; for example {fr_1, fr_2, ..., fr_n}. The list is “multiplied” by each natural frequency to provide a list of excitation frequencies for each natural frequency; for example fn_j * {fr_1, fr_2, ..., fr_n}, where fn_j is the jth natural frequency. The fractions cannot be inserted on a single row of the Define Frequencies form, but multiple rows must be created, with just one fraction per row.

Define Damping

Use this form to define the damping in a linear table. Values of frequency must be positive. Discontinuities (same value of frequency, different value of damping) are allowed at all locations except the first and last entries in the table. See MSC Nastran Quick Reference Guide TABDMP1 for more information. Modal Damping does not allow a discontinuity to exist as either the first or last entry in the modal damping data. This will cause an error in MSC Nastran. It is strongly recommended that you do not create such scenario. If the first and second frequencies (two lowest frequencies) are the same value, a warning will be issued, even if the damping values for those frequencies are the same. If the last and second to last frequencies

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(two highest frequencies) are the same value, a warning will be issued, even if the damping values for those frequencies are the same.

Parameter Name

Main Index

Description

Add Row

"Add Row" adds a row after the selected row. To insert a row at the beginning of the table, click on the row label and select "Add Row".

Create a Field

To create a Field for the damping data, click in the Create a Field checkbox.

Load Dara From Field

To bring in damping data from an existing Field, click on the Load Data From Field button, then select the Field.

Chapter 3: Running an Analysis 433 Subcase Parameters

Spinning Properties, Frequency Response

Presented when Rotor Dynamics is ON and the Specify Spinning Properties button is selected.

Parameter Name Option

Description Synchronous (default) or Asynchronous Defines the SYNCFLG field of the MSC Nastran RGYRO Bulk Data entry.

Reference Rotor

Main Index

The reference rotor for the subcase. This drives the RGYRO Case Dontrol and Bulk Data (REFROTR field) in the MSC Nastran Bulk Data file.

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Parameter Name

Description

Speed Unit

Relative speeds to the reference rotor. These values define the SPDUNIT, SPDHIGH, and SPDLOW fields of the MSC Nastran RGYRO Bulk Data entry. The SPEED value is left lank.

Speed High / Speed Low

For Asynchronous analyses, a single Speed databox is presented, defining SPEED field, while SPDHIGH and SPDLOW are left blank. For Synchronous analyses with Frequency Dependent Looping OFF, no speed databoxes are presented, and SPDHIGH, SPDLOW, SPEED are all left blank. Rather, a “param, gyroavg,-1” entry is generated. Frequency Dependent Looping is ON by default.

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Chapter 3: Running an Analysis 435 Subcase Parameters

Implicit Nonlinear Subcase Parameters The type of nonlinear analysis can be changed in each SOL 600 or SOL 400 subcase. To specify this change, the Subcases form includes an Analysis Type pull-down menu with options for static, normal modes, buckling, transient dynamic, creep, and body approach analyses. For SOL 400 there is an additional Analysis Type, complex eigenvalue. In turn, specifying the subcase parameters is dependent on the Analysis Type selected for the subcase. The following sections define the subcase parameters for each analysis type.

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Static Subcase Parameters for Implicit Nonlinear Solution Type This subform defines the parameters for a SOL 400 or 600 static analysis subcase.

Parameter Name Linearity

Description Prescribes the nonlinear effects for the subcase.

Nonlinear Solution Parameters • Nonlinear Geometric

Effects

Main Index

Defines the type of geometric or material nonlinearity to be included in the subcase.

• Follower Forces

Specifies whether forces will follow displacements.

Use Contact Table

Toggle button to enable or disable the use of Contact Table.

Chapter 3: Running an Analysis 437 Subcase Parameters

Parameter Name

Description

Load Increment Parameters

Defines whether the load increments will be fixed or adapted in each iteration and the method by which adaptive load increments will be determined.

Iteration Parameters

Sets forth the iterative procedures that are employed to solve the equilibrium problem at each load increment.

Contact Table

Activates, deactivates, and controls the behavior of contact bodies in the analysis.

Active/Deactive Elements

Defines groups of elements to be active or deactive for the subcase.

Break Squeal Parameters

For defining parameter values for modeling break squeal for the subcase. (SOL 400 only).

Implicit Nonlinear Normal Modes Subcase Parameters This subform defines the parameters for a normal modes analysis subcase (SOL 400 and 600 only). See Normal Modes Subcase Parameters, 421 for more information. Implicit Nonlinear Buckling Subcase Parameters For buckling nonlinear analysis the subcase parameters control the eigenvalue extraction techniques and the range of frequencies to be targeted for extraction. This subform defines the parameters for a buckling analysis subcase (SOL 400 and 600 only). See Normal Modes Subcase Parameters, 421 for more information.

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Implicit Nonlinear Transient Dynamic Subcase Parameters This subform defines the parameters for a transient dynamic analysis subcase for SOL 600 and SOL 400.

Parameter Name Linearity

Description Prescribes the nonlinear effects for the subcase.

Nonlinear Solution Parameters • Nonlinear Geometric

Effects

Main Index

Defines the type of geometric or material nonlinearity to be included in the subcase.

• Follower Forces

Specifies whether forces will follow displacements.

Use Contact Table

Toggle button to enable or disable the use of Contact Table.

Chapter 3: Running an Analysis 439 Subcase Parameters

Parameter Name

Main Index

Description

Load Increment Parameters

Defines whether the load increments will be fixed or adapted in each iteration and the method by which adaptive load increments will be determined.

Iteration Parameters

Sets forth the iterative procedures that are employed to solve the equilibrium problem at each load increment.

Contact Table

Activates, deactivates, and controls the behavior of contact bodies in the analysis.

Active/Deactive Elements

Defines groups of elements to be active or deactive for the subcase (SOL 600 only).

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Implicit Nonlinear Creep Subcase Parameters This subform defines the parameters for a SOL 600 and SOL 400 Creep analysis subcase.

Parameter Name

Description

Creep Solution Parameters • Procedure

Defines either Explicit creep formulation or Implicit creep formulation.

• Nonlinear Geometric

Defines the type of geometric or material nonlinearity to be included in the subcase.

Effects

Main Index

• Follower Forces

Specifies whether forces will follow displacements.

Increment Type

Defines a fixed or adaptive increment method.

Chapter 3: Running an Analysis 441 Subcase Parameters

Parameter Name • Adaptive Increment

Description For adaptive methods, sets boundaries for incrementation.

Parameters... Use Contact Table

Toggle button to enable or disable the use of Contact Table.

Load Increment Parameters

Defines whether the load increments will be fixed or adapted in each iteration and the method by which adaptive load increments will be determined.

Iteration Parameters

Sets forth the iterative procedures that are employed to solve the equilibrium problem at each load increment.

Contact Table

Activates, deactivates, and controls the behavior of contact bodies in the analysis.

Active/Deactive Elements

Defines groups of elements to be active or deactive for the subcase (SOL 600 only).

Break Squeal Parameters Implicit Nonlinear Body Approach Subcase Parameters This subform defines the parameters for a SOL 600 body approach analysis subcase

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Parameter Name

Description

Body Approach Parameters • Total Time

Places a time step option in the Load Step.

• Synchronized

If ON, specifies that when the first rigid body comes into contact, the rest stop moving.

Contact Table

Activates, deactivates, and controls the behavior of contact bodies in the analysis. See Contact Table, 456

Implicit Nonlinear Complex Eigenvalue Subcase Parameters This subform defines the parameters for a SOL 400 (only) complex eigenvalue analysis subcase

Parameter Name

Main Index

Description

Formulation

Select either Direct or Modal.

Enable Rotor Dynamics

Click in checkbox to activate rotor dynamics.

Specify Spinning Properties...

Click to access the form for specifying the rotor speed. See Spinning Properties, Frequency Response, 433

Chapter 3: Running an Analysis 443 Subcase Parameters

Parameter Name

Description

Use Contact Table

Toggle button to enable or disable the use of Contact Table.

Contact Table...

Activates, deactivates, and controls the behavior of contact bodies in the analysis. See Contact Table, 456

Load Increment Parameters Load and time step incrementation parameters for Statics and Transient Dynamics appear on this subordinate form. For other analysis types, this information appears directly on the Solution Parameters form.

The Load Increment Parameters form differs depending on your designation of a Fixed or Adaptive Increment Type and whether an arclength method is to be used if you select an Adaptive Incrementation scheme.

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Adaptive Load Incrementation without Arclength

Static

Transient Dynamic

For SOL 400 in versions of MSC Nastran less than 2010, these parameters in this form are written to the NLADAPT and NLPARM entries. For MSC Nastran 2010 or later, these parameters are written to the NLSTEP entry. For SOL 600, the NLAUTO entry is written for all versions of MSC Nastran. Increment Type

Adaptive

Arclength Method

None

Trial Time Step Size

Defines the initial time step size. Default is 1% of Total Time if left blank.

Time Step Scale Factor

Indicates load will be allowed to be scaled up by 20% each increment if possible. Default is 1.2.

Minimum Time Step

Indicates the smallest time step that can be used. Default is Trial Time Step / 1000 if left blank.

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Chapter 3: Running an Analysis 445 Subcase Parameters

Maximum Time Step

Indicates the largest time step that can be used. Default is Total Time / 2 if left blank.

Maximum # of Steps

Defines the maximum number of time steps. It can be left blank which will default to the Initial Step Size divided by the Total Time.

Total Time

This is the total time of the analysis for a particular step. It defaults to one (1) if left blank for static load cases. For time dependent load cases, the total time is the length of time between distinct time points if left blank. Otherwise the actual value is used (not recommended because it can’t be variable).

# of Steps of Output

Indicates that this many increments evenly spaced in time will be place in the output file. Default is 0 if left blank. Which means all converged increments will be output (SOL 600 only).

Quasi-static Inertial Damping

ON by default.

Criteria

Multiple adaptive load stepping criteria is available. By default, none of this is necessary. These criteria are described below in Adaptive Load Incrementation Criteria, 447.

Time Integration Scheme

For Transient Dynamics, indicates the time integration scheme to use in dynamic analysis.

Minimum Iteration per Increment

Enter these values for a SOL 400 run. For SOL 600 these values are defined on the Iteration Parameters, 451 form.

Maximum Iteration per Increment

Enter these values for a SOL 400 run. For SOL 600 these values are defined on the Iteration Parameters, 451 form.

Matrix Update Method

This is the method for controlling stiffness updates. This is the KMETHOD field on the NLPARM entry for SOL 400 runs.

Load Increment Parameters for SOL 600 and SOL 400, Creep analysis. The MSC Nastran entries used for this are NLADAPT, NLPARM, and TSTEPNL.

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Creep

Increment Type

There are three choices, 1) Fixed, 2) Adaptive, and 3) Adaptive Creep.

Suggested Time Increment

The approximate time step.

Total Time

The total time for the creep analysis.

Max # of Increment Allowed

This is for NSMAX.

Creep Tests

This is for RAC.

Relative Strain Tolerance

This is for TCSTRN.

Relative Stress Tolerance

This is for TCSTRS.

Low Stress Cut-off Tolerance

This is for TCOFF.

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Chapter 3: Running an Analysis 447 Subcase Parameters

Adaptive Load Incrementation Criteria

Parameters on this form are written to the MSC Nastran NLAUTO entry for SOL 600, when defining automatic adaptive load incrementation and to the TABSCTL entry for SOL 400, which are referenced from the NLSTEP entry. Adaptive Criteria

Description

Treat Criteria as:

If Limits, sets 3rd field to zero (0) in 3rd data block (default). If Targets, sets field to one (1). This is for LIMITAR.

Use Automatic Criteria Continue if not Satisfied

Uses automatic physical criteria if top toggle is ON. Bottom toggle defines what happens if the criteria is not met. Both OFF by default. This is for IPHYS.

Ratio Between Steps:

Defines the [Smallest] and [Largest] ratios acceptable between load increments. For Smallest, default = 0.1, For Largest, default=10.0. This is for RSMALL and RBIG.

[Number of Cutbacks]

Blank by default. default value is 10 if left blank or zero. This is for NCUT.

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Adaptive Criteria Increment Criteria

Description Selects the type of criteria to be used.The labels “XXX Range” and “XXX Increment Allowed” will change based on the Increment Criteria selected. This is for CRITERIA.

Loading Table Instances

Determines how loading tables (Use Tables must be ON in the Job Parameters form) are treated. By default loads are increased or decreased such that they always Reach Peaks-Valleys Only. If you wish you can Reach All Points in Tables or Ignore all Points in Tables.

Write Instances to Post File

Writes Loading Table Instances to the Post file if toggle is ON. Note that if toggle is ON, then only those instances are written to the POST file and not all the increments of the analysis. This is for IDMPFLG.

Nodal Temp. Check

There are three choices, 1) Omit Check, 2) Below Finish Temperature (to complete time period when all node temperatures are < FTEMP), and 3) Above Finish Temperature (to complete time period when all node temperatures are > FTEMP). This is for IFINISH.

Finish Temperature

The terminal temperature. This is for FTEMP.

Use Criterion

For a criteria to be used, this toggle must be turned ON.

“Criterion” Range

The first and last fields are zero and 1e20 respectively and cannot change. The second and third must be the same as well as the 4th/5th and 6th/7th which define the ranges. The “Criterion” title changes according to the Increment Criterion chosen.

“Criterion” Increment Allowed

The “Criterion” title changes according to the Increment Criteria chosen.

Select a Group (Optional)

You can optionally select a group of elements to which this criterion is to be applied. No group is selected by default.

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Chapter 3: Running an Analysis 449 Subcase Parameters

Adaptive Load Incrementation with Arclength (SOL 600 only) Static

Adaptive Increment Parameter

Description

Arclength Method

Selects the arclength root procedure: Crisfield, Riks/Ramm, Modified Riks/Ramm, or Crisfield-Modified Riks/Ramm. The default is Modified Riks/Ram. If None is selected the form updates as shown (p. 443). For Transient Dynamics, this is the only option available for adaptive load incrementation.

Automatic Cutback

This feature is ON by default. If an increment does not converge, a restart from the last increment cuts the increment size in half.

Number of Cutbacks

This is associated with Automatic Cutback. This parameter determines how many times a cutback is allowed.

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Adaptive Increment Parameter

Description

Initial Fraction of Load Applied to 1st Increment

This is the fraction of the total load that should be applied in the first iteration of the first increment.

Max. Fraction of Load Applied in Any Increment

This is the maximum fraction of the load that can be applied in any increment.

Max/Min Ratio Arc Length / Initial Arc Length

Used to define the minimal arclength. The default is 0.01.

Max. # of Increments

Defines the maximum number of increments. Program will end if this value is exceeded.

Total Time

This is the total time of the analysis for a particular step. It defaults to one (1) if left blank for static load cases. For time dependent load cases, the total time is the length of time between distinct time points if left blank. Otherwise the actual value is used (not recommended because it can’t be variable). Fixed Load Incrementation

Static

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Transient Dynamic

Chapter 3: Running an Analysis 451 Subcase Parameters

Fixed Increment Parameter

Description

Automatic Cutback

Applies to Nonlinear Statics only. It is ON by default. If an increment does not converge, it allows for a restart from the last increment cuts the increment size in half.

Number of Cutbacks

This is associated with Automatic Cutback. This parameter determines how many times a cutback is allowed.

Number of Increments or Number of Steps

For Statics and Creep this is the number of increments specified in the NLAUTO option. Or for Transient Dynamics defines the number of steps to use throughout the analysis for Fixed time step type. Default is 10.

Total Time

For Statics, this enters the NLAUTO option which is the total time as defined in this widget. For Transient Dynamics this is the total time. For Creep, the total time is either placed in the 2nd data block of a CREEP INCREMENT option or the total time is divided by the Number of Increments, if this value is present, and the incremental time is written to the 2nd data block of the CREEP option.

Gamma / Beta

For Transient Dynamics only. Default is 0.5.

Time Integration Scheme

For Transient Dynamics, the Houbolt and Central Difference cannot be selected. Indicates the time integration scheme to use in dynamic analysis.Single Step Houbolt is the default.

Minimum Iteration per Increment

Enter these values for a SOL 400 run. For SOL 600 these values are defined on the Iteration Parameters, 451 form.

Maximum Iteration per Increment

Enter these values for a SOL 400 run. For SOL 600 these values are defined on the Iteration Parameters, 451 form.

Matrix Update Method

This is the method for controlling stiffness updates. This is the KMETHOD field on the NLPARM entry for SOL 400 runs.

Iteration Parameters This subordinate form appears when the Subcase Parameters... / Iteration Parameters... button is selected for Analysis Type: Static, Transient Dynamics, Creep, ... Subcases form. Unless otherwise specified all

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parameter references apply to the NLSTRAT (SOL600) entry for the form on the left, and NLPARM (SOL 400) entry for the form on the right .

SOL 600 Iteration Parameter

Description

Proceed if not Converged

Forces the analysis to proceed even if the increment did not converge.

Initial Stress Stiffness

There are five choices, 1) Full, 2) None, 3) Tensile, 4) Deviatoric, and 5) Begin Increment.

Non-positive Definite

This forces the non-positive definite flag (IKNONPOS param) ON in the NLSTRAT option. A new NLSTRAT option is written for each step if a change in this flag has been detected from Subcase to Subcase.

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Chapter 3: Running an Analysis 453 Subcase Parameters

SOL 600 Iteration Parameter

Description

Iteration Method

Indicates the iteration method (IKMETH param) to be used. This is can be set to Full Newton-Raphson, Modified Newton-Raphson, NewtonRaphson with Strain Correction, or Secant Method. Full Newton-Raphson is default.

Max # of Iterations per Increment

Defines the maximum number of iterations (MAXREC param) allowed for convergence in any increment. This number is negative if Proceed if not Converged is ON from the Solution Parameter form.

Minimum # of Iterations

This specifies the minimum number of iterations per Increment (MINREC param) option. It can be an integer number zero or greater. If this is set greater than zero, every increment will perform at least this many iterations.

per Increment Desired # of Iterations per Increment

Defines the number of desired iterations in an increment (ATRECYC param) which is placed on the NLSTRAT option. If the actual number of iterations is less than this value, this will be used to figure out how much to increase the load step for the next increment. In a similar manner if the actual number of iterations is greater than this number (but less than the Max # of Iterations per Increment, this will be used to decrease the load step in the next increment. Obviously if Adaptive incrementation is not specified, this data will not be used.

Matrix Update Method

There are six choices for updating the stiffness matrix, 1) Automatic (MSC Nastran automatically selects the most efficient strategy based on convergence rates), 2) Controlled Iters.(MSC Nastran updates the matrix at every KSTEP interations and at convergence if KSTEP First - Blanks the upper triangular section of the table matrix such that

no input can be accepted. Only the contact bodies from the lower portion are written. Contact detection is done opposite of First->Second. • Double-Sided -Writes both upper and lower portions of the table matrix. This

overrules the Single Sided contact parameter set on the Contact Parameters subform. Touch All

Places a T to indicate touching status for all deformable-deformable or rigiddeformable bodies.

Glue All

Places a G to indicate glued status for all deformable-deformable or rigid-deformable bodies.

Deactivate All

Blanks the spreadsheet cells.

Import/Export

Import or Export a file with contact matrix definition data. The format must be CSV.

Select Existing

Select an existing Contact Table from a set of tables.

Contact Matrix

A matrix defining what and how contact bodies contact.

Body Type

Lists the body type for each body; either Deformable or Rigid.

Release

This cell can be toggled for each body to Y or N (Yes or No). If Y, this indicates that the particular contact body is to be removed from this Subcase. The forces associated with this body can be removed immediately in the first increment or gradually over the time of the entire Subcase with the Force Removal switch described below.

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Input

Description

The Contact Matrix entries

The rows correspond to Touching Body. The columns correspond to Touched Body. An entry of the matrix, for example (Row i,Column j), will have the entry of T, G, or “blank”. T = touching, G = glue, “blank” = no contact. To change a matrix cell entry, select the cell (click once) to select it, then click on the cell once to change to the next selection. For example, T -> G.

Touching Body Touched Body

These are informational or convenience list boxes to allow you to see which bodies an active cell references and to see what settings are active for Distance Tolerance and other related parameters below. You must click on the touched/touching bodies to see what values, if any, have been set for the pair combination.

Distance Tolerance

Set the Distance Tolerance for this pair of contact bodies. You must press the Enter or Return key to accept the data in this data box. A nonspatial field can be referenced that will write this data in TABLE format, if this parameter varies with time, temperature, or some other independent variable. This overrides any other settings for Distance Tolerance.

Bias Factor

Bias the domain defined by the distance tolerance.

Analysis Properties

Select Structural.

Separation Threshold

Specify a threshold (force or stress) such that if the contact load (force or stress) is < this threshold value, the contacting body remains in contact with the contacted body.

Separation Force

Set the Separation Force for this pair of contact bodies. You must press the Enter or Return key to accept the data in this data box. A nonspatial field can be referenced that will write this data in TABLE format, if this parameter varies with time, temperature, or some other independent variable. This overrides any other settings for Separation Force.

Friction Coefficient

Set the Friction Coefficient for this pair of contact bodies. You must press the Enter or Return key to accept the data in this data box. A nonspatial field can be referenced that will write this data in TABLE format, if this parameter varies with time, temperature, or some other independent variable. This overrides any other settings for Friction Coefficient.

Interference Closure

Set the Interference Closure for this pair of contact bodies. You must press the Enter or Return key to accept the data in this data box. A nonspatial field can be referenced that will write this data in TABLE format, if this parameter varies with time, temperature, or some other independent variable. This overrides any other settings for Interference Closure.

Friction Stress Limit

This is a bound on the maximum friction stress. This is the friction stress limit for the bilinear model, σ t limit . If the shear stress reaches the limit value, the applied friction force is reduced so that the maximum shear stress is given by min ( μσ n, σ limit ). t

Slide Off Distance

Main Index

Specify the distance a node must slide off a surface, at an edge, before the node travels on the surface, at the edge, that is at an angle to the surface that is being slid off of.

Chapter 3: Running an Analysis 459 Subcase Parameters

Input

Description

Heat Transfer Coefficient

Set the Heat Transfer Coefficient for this pair of contact bodies. You must press the Enter or Return key to accept the data in this data box. A nonspatial field can be referenced that will write this data in TABLE format, if this parameter varies with time, temperature, or some other independent variable. This overrides any other settings for Heat Transfer Coefficient. This is only used in Coupled analysis (Heat transfer and Coupled analysis not supported in MSC.Nastran 2004.

Force Removal

Select 1) Immediate, or 2) Gradual. This is activated when a body is set to Release. For example, 1-seal can be set to Release by clicking once on the corresponding Release cell, then clicking once again to change from N to Y. The MSC Nastran entry BCMOVE is written to the .bdf file. On the Contact Table form, there is a column for body Release that writes a BCMOVE entry. The new Body Pair enhancement does not address this in the current design and the BCMOVE entry does not get written in .bdf file while using Contact Body Pairs.

Contact Detection

Select 1) Automatic, 2) Double Sided, 3) 1st->2nd, or 4) 2nd->1st.

Retain Gaps/Overlaps

This is only applicable for the Glued option. Any initial gap or overlap between the node and the contacted body will not be removed (otherwise the node is projected onto the body which is the default). For deformable-deformable contact only.

Stress-free Initial Contact

This is only applicable for initial contact in increment zero, where coordinates of nodes in contact can be adapted such that they cause stress-free initial contact. This is important if, due to inaccuracies during mesh generation, there is a small gap/overlap between a node and the contacted element edge/face. For deformable-deformable contact only.

Delayed Slide Off

By default, at sharp corners, a node will slide off a contacted segment as soon as it passes the corner by a distance greater than the contact error tolerance. This extends this tangential tolerance. For deformable-deformable contact only.

Allow Separation Advanced Parameters...

See Advanced Parameters Subform, 459

Contact Boundary...

See Contact Boundary Subform, 462

Advanced Parameters Subform Un-gluing (breaking) a glued contact can be done by specifying the Breaking Glue Parameter values in the following form. Also augmentation parameters for Segment-to-Segment contact can be specified per contact pair as well. Note that you MUST press the OK button to save the settings on this form for a given

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contact pair. You must open and repeat this operation for each pair you for which you wish to defined these properties.

Breaking Glue - This toggle and its parameters can only be used when there is glued contact (there is G in the Contact Table matrix cells) and is only valid for Nastran 2010 or higher. Input

Description

Max Normal Stress

The maximum normal stress that will cause the glued contact to become un-glued.

Max Tangential Stress

The maximum tangential stress that will cause the glued contact to become un-glued.

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Chapter 3: Running an Analysis 461 Subcase Parameters

Input

Description

First Exponent

The exponent of the tangential stress term (BGM) in the following equation:  sigman --------------------  BGSN 

Second Exponent

BGN

sigmat BGM +  ------------------ > 1.0  BGST 

The exponent of the normal stress term (BGN) in the following equation:  sigman --------------------  BGSN 

BGN

sigmat BGM +  ------------------ > 1.0  BGST 

Segment-to-Segment Contact - This toggle and its parameters are used when segment-to-segment contact is specified. These parameters are only valid for Nastran 2010 or higher and currently only the normal values are supported. They are written to the BCTABLE entry under the “SEGS” line in the PENALT and AUGDIST field. Segment-to-segment contact must be turned on the Contact Options form, otherwise these parameters are ignored. (See Contact Parameters Subform, 350.) Input

Description

Normal Penalty Factor The augmented lagrange penalty factor used by the segment-to-segment contact algorithm. Penetration Distance

The penetration distance beyond which the augmentation will be applied as used by the segment-to-segment contact algorithm.

Tangential Penalty Factor

Not supported by Nastran yet.

Slip Distnace

Not supported by Nastran yet.

Anisotropic Friction - Not supported by Nastran yet. Wear Scale Factor - Not supported by Nastran yet.

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Contact Boundary Subform :

All of the flags on this form are written to the BCTABLE entry under the “FBSH” line in the COPTS1 and COPTM1 fields. Input

Description

Include Outside (Solid Element)

When detecting contact of solid elements (for example, CHEXA elements) use this to include contact of the outside of the elements.For details refer to the BCTABLE entry (defines contact table) of the MSC Nastran QRG. The entries that are used for the BCTABLE entry are COPTM and COPTS. These flags indicate how master and slave surfaces may contact.

Include Outside of Rigid Surface

When detecting contact of rigid surfaces use this to include contact of the outside of the rigid surfaces. For details refer to the BCTABLE entry (defines contact table) of the MSC Nastran QRG. The entries that are used for the BCTABLE entry are COPTM and COPTS. These flags indicate how master and slave surfaces may contact.

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Chapter 3: Running an Analysis 463 Subcase Parameters

Input

Description

Check Layers

For contact bodies composed of shell elements, this option menu chooses the layers to be checked. Available options are: Top and Bottom, Top Only, Bottom Only. Check Layers and Ignore Thickness combination enters the appropriate flag in the 10th field of the 2nd data block.

Ignore Thickness

Turn this button ON to ignore shell thickness. Check Layers and Ignore Thickness combination enters the appropriate flag in the 10th field of the 2nd data block.

Include Edges

Use this to detect contact of edges. There are three options, Beam/Bar, Free and Hard Shell, or Both. For details refer to the BCTABLE entry (defines contact table) of the MSC Nastran QRG. The entries that are used for the BCTABLE entry are COPTM and COPTS. These flags indicate how master and slave surfaces may contact.

Active/Deactive Elements Defines groups of elements to be active or deactive for the subcase.

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Active/Deactive Group

Description

Group of Element to Deactivate

Lists all groups. Elements in the selected group will be deactivated.

Group of Elements to Activate

Lists all groups. Elements in the selected group will be activated.

Break Squeal Parameters Defines parameter values for modeling break squeal. (SOL 400 only).

Active/Deactive Group

Description

Enable Break Squeal

The form is activated when this checkbox is selected.

Load Factor

Defines the load factor for which the break squeal analysis is to be performed.

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Chapter 3: Running an Analysis 465 Subcase Parameters

Active/Deactive Group

Description

Average Stiffness

Approximate average stiffness per unit area between the break pads and disk. This parameter is used as a penalty contact stiffness for break squeal. It needs to be a large value, but not so large that numerical instabilities result. If this parameter is large enough, increasing it by a few orders of magnitude will not appreciably affect the squeal modes.

Break Squeal Only

This is used to specify whether or not the nonlinear analysis will be continued after the break squeal event. If this is selected, the nonlinear iterations will cease immediately after the event, otherwise the nonlinear iterations will be continued.

Axis of Rotation Vector

This is a vector of direction cosines, , where this is for the axis of rotation, and the directions are in the basic coordinate system.

Point on Axis of Rotation

These are the coordinates of a point on the axis of rotation, [X,Y,Z]. The coordinates are in the basic coordinate system.

Solvers/Options In general, this form is used to select the Nastran solver and other possible options. An SMETHOD case control entry is written specifying the solver type to use and possibly an ITER bulk data entry for additional options. Only certain solutions allow the use of the SMETHOD case control as controlled by

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the user interface. If a solution does not support a solver option, that option is not presented in the form or menus.

Solver Type

Description

Nastran Default

No SMETHOD or ITER entries are written. Nastran uses whatever solver is the default for the solution being used.

Iterative ElementBased (CASI)

An SMETHOD case control with the entry ELEMENT is used which invokes the iterative CASI (element-based) solver using all defaults. This is only available for SOL 101 and 400 and is generally used with large solid models. Certain restrictions apply and you should consult the Nastran Quick Reference Guide regarding the usage of this solver.

Iterative Matrix-Based

An SMETHOD case control with the entry MATRIX is used to invoke the matrix-based iterative solver using all defaults.

Iterative (Customized)

An SMETHOD case control referencing the ID of an ITER bulk data entry is written to the input deck. The ITER entry invokes the solver options. Those options are described in the table below.

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Chapter 3: Running an Analysis 467 Subcase Parameters

Iterative Option

Description

Preconditioner

Five preconditioners are available: Jacobi, Cholesky, Jacobi/Cholesky, and CASI. The CASI is the element-based iterative solver. See the table above. All other preconditioners are the matrix-based iterative solver. Various options are allowed for each as controlled by the user interface. See the entries below. To use a default preconditioner based on the solution type, set this to Analysis Default. Consult the Nastran Quick Reference Guide for more details as to which defaults are used for each solution type.

Maximum Number of Iterations

Leave this blank to accept the default. Otherwise specify the maximum number of iterations allowed.

Diagonal Scaling

The Jacobi and Cholesky preconditioners allow diagonal scaling.

Reduced

Turn this toggle on to invoke the reduced incomplete Cholesky preconditioner as opposed to just the incomplete Cholesky. This can be combined with or without diagonal scaling.

Block

Turn this toggle on to invoke the block incomplete Cholesky preconditioner. You must specify real or complex also.

Real / Complex

This is only used for the block incomplete Cholesky preconditioner.

p-version

For p-element analysis, you can turn this toggle on to invoke the Jacobi, Cholesky or combined Cholesky/Jacobi preconditioner. This cannot be combined with any other options.

Padding

Specify the padding value for reduced incomplete Cholesky with any of its options. Leave this blank to specify the defaults. Each option has its own default, therefore it is recommended that you leave this blank.

Extraction

Specify the extraction level for reduced or block incomplete Cholesky preconditioner. The default is zero.

Geometric Progression Turn this toggle on if you wish to use geometric progression convergence criterion. Epsilon

This is a user-given convergence parameter. Default is 1e-6. If present, the solver will use additional external convergence criterion. See the Nastran Quick Reference Guide for more details. Blank this field out if only the internal convergence criterion is required.

Print Messages for each Iteration

Off by default. Turn ON if you want more diagnostics for each iteration. Otherwise only minimal messaging is given.

Terminate Early (Resource Estimate Only)

Turn this toggle ON if you want the run to terminate with only a resource estimation.

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DDAM Subcase Parameters This subform defines the parameters for a SOL 187 DDAM analysis subcase

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Chapter 3: Running an Analysis 469 Subcase Parameters

Spectrum Source

Select File for a user-defined spectrum, or Coef for a DDAM style coefficient equation. If you select File, a button appears to the right to let you select the file where the spectrum is defined. If you select Coef, two other buttons appear:

Coef Source

Select File for a user-written coefficient file, or Default to use the coefficients built into the Fortran program. Note that the built-in coefficients we deliver in the program are NOT the DDS-072 coefficients. If you use this option for a real DDAM analysis, the Fortran file must be edited and recompiled. If you select File, a button appears to the right to let you choose the file where the coefficient data is stored.

F(x) Type

Choices are NRL 1396 and DDS 072. This option toggles between the old NRL 1396 style equations, and the current DDS-072 style equations used for DDAM.

Coefficient Options • Ship Type

Select Surface or Submerged

• Mount Location

Choice of Deck, Hull, or Shell.

• Elastic/Plastic

Select Elastic or Plastic. Choosing Plastic uses the Elastic/Plastic coefficients; Elastic uses the elastic coefficients.

Weight Cutoff

Default uses the default value compiled into the PCL code, which is 80%. If you choose Enter Value the text box becomes available and you can enter a percentage manually. The number entered is the percentage, not the fraction, so 100% of the modal mass is entered as 100.

Minimum G Level

If you select N/A, no minimum G value is used. If you enter a value, all modal accelerations below the minimum are set to the minimum.

Fore/Aft Axis

It is necessary to have the model oriented orthogonal to a global cartesian axis system, although not necessarily in one particular orientation. This toggle identifies which global axis is to be interpreted as Fore/Aft.

Vertical Axis

This identifies the axis that is in the vertical direction.

Modal Analysis • Number of Desired Roots • Lower • Upper

Main Index

These are the limits that control the eigenvalue analysis and are the values from the Nastran EIGRL entry. ND is the number of desired roots, V1 is the lower frequency limit, V2 is the upper frequency limit. For the effects of using one of more of these, see the EIGRL section of the MSC Nastran Quick Reference Guide.

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Explicit Nonlinear Subcase Parameters This subordinate form appears when the Subcase Parameters button is selected on the Subcases form when the solution type is Explicit Nonlinear. All of the data is part of the TSTEPNL Bulk Data entry

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Chapter 3: Running an Analysis 471 Subcase Parameters

Work Tolerance

Defines BCTABLE. Similar to SOL 600 - Implicit Nonlinear

Contact Table...

Activates, deactivates, and controls the behavior of contact bodies in the analysis.

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Chapter 3: Running an Analysis 473 Subcase Parameters

Frequency Range of Interest

Selects the highest and lowest natural frequency values to be extracted

Degree of Freedom to Determine the Selects which Degrees of Freedom are used to determine the peaks Peaks Output Interval

Selects the output interval of accelerations, velocities, or displacements of the eigenvalues

Type of Response

The “Type of Response” menu specifies whether Acceleration, Velocity, or Displacement response will be used to select the modes.

Degrees of Freedom

Selects which Degrees of Freedom to be in the eigenvectors (3 for translations only, 6 for translations and rotations

Method of Normalization

The “Method of Normalization” menu specifies the method used to normalize the eigenvectors

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Contact Table A contact table is used to control the behavior of contact bodies and to activate or deactivate, or in some cases, remove contact bodies from the analysis. This form defines the BCTABLE entry.

Additional Data...

Main Index

Additional Contact Data for Explicit Nonlinear.

Chapter 3: Running an Analysis 475 Subcase Parameters

Additional Contact Data This subordinate form defines additional contact data for Explicit Nonlinear.

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Adaptive Mesh Post-Processing Support has been added for adaptive mesh post-processing for airbag analysis. Below is an adapted mesh model as read in from the DBALL file and stored using offset ID’s in separate groups. The user can then select one or more time increments from the Quick Plot Results menu for postprocessing. The Quick Plot algorithm pulls up the mesh associated with the increment(s) selected for post-processing. Using this method a user can do a pseudo-animation to show the progression of the analysis. The model is loaded by a cylindrical rigid pin with a 200 lb load at the center.

Additional Information The following is also now supported for SOL 700 jobs: • Additional Properties • PBEAM71 • BPEAMD • PBELTD • PELAS1 • PLPLANE • PLSOLID • PSHELL1 • PSHELLD • PSPRMA

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Chapter 3: Running an Analysis 477 Subcase Parameters

• GUI for time domain NVH • Many additional materials

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3.9

Output Requests This allows the definition of what data is desired from the analysis code in the form of results. For most solution sequences, the form consists of two formats: Basic and Advanced. The Basic form retains the simplicity of being able to specify the output requests over the entire model and uses the default settings of MSC Nastran Case Control commands. There is a special set defined in Patran called ALL FEM. This set represents all nodes and elements associated with Object defined on the Analysis Form, 293. This default set is used for all output requests in the Basic Output Requests, 479 form. The Advanced version of this form allows the user to vary these default options. Since output requests have to be appropriate to the type of analysis, the form changes depending on the solution sequence. The Advanced Output Requests, 481 also adds the capability of being able to associate a given output request to a subset of the model using Patran groups. This capability can be used effectively in significantly reducing the results that are created for a model, optimizing the sizes and translation times of output files. The creation of Patran groups are documented in Group>Create (p. 249) in the Patran Reference Manual. The results types that will be brought into Patran due to any of these requests, are documented in Supported OUTPUT2 Result and Model Quantities, 574. In that chapter, tables are presented that correlate

the MSC Nastran results block, and the Patran primary and secondary results labels with the various output requests. Note:

Many of the output requests that can be defined on the Output Request forms currently apply only to the printed values in the MSC Nastran output file; these result quantities cannot be imported and postprocessed in Patran. For guidance on specific quantities, review Supported OUTPUT2 Result and Model Quantities, 574.

MSC Nastran Implicit Nonlinear (SOL 600) produces stress and strain results that differ from those results available with other solution sequences. A detailed discussion of the stress and strain measures for SOL 600 is given in Stress and Strain Measures for Nonlinear Analysis (Ch. 2) in the MSC.Nastran Implicit Nonlinear (SOL 600) User’s Guide.

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Chapter 3: Running an Analysis 479 Output Requests

Basic Output Requests This form is used to select output requests with their default options. The set is always All FEM, which means results for all nodes or elements in the model. A default set of output requests is always preselected.

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Parameter Name Solution Sequence

The available output requests depend on the active Solution Sequence as indicated by this value.

Form Type

This option menu is used to switch between the advanced and basic versions of this form.

Select Result Type

This listbox displays the appropriate result types that may be selected for the solution sequence indicated at the top of the form. The output requests are selected one at a time by clicking.

Output Requests

This listbox displays the selected output requests for the subcase shown at the top of the form.

Delete

The Delete button deletes the output request highlighted in the Output Requests listbox.

TITLE, SUBTITLE and LABEL

The TITLE, SUBTITLE and LABEL are written to the MSC Nastran output file.

Note:

Main Index

Description

The OK button accepts the output requests and closes the form. The Defaults button deletes all output requests and replaces them with defaults. The Cancel button closes the form without saving the output requests.

Chapter 3: Running an Analysis 481 Output Requests

Advanced Output Requests This form provides great flexibility in creating output requests. Output requests may be associated with different groups (SET options in MSC Nastran) as well as different superelements1. The output requests available depend on the chosen Solution Types, 305, Solution Parameters, 312, and Translation Parameters, 298 . The Advanced Output Requests form is sensitive to the Result Type selected. The Form Type, Delete, OK, Defaults, and Cancel buttons operate exactly like on the Basic Output Requests, 479 form. A description of the output requests and their associated options are listed in Table 3-1 and Table 3-2.

1At the present time, superelement specifications are allowed only in the structured linear static solution

type (Solution Sequence 101).

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Parameter Name

Description

Select Result Type

Use this listbox to select the result type to be created.

Output Requests

Use this list box to select output requests that are to be modified or deleted.

Select Group(s)/SET

This listbox is used to select the group to which the output requests relate.

Tensor / Element Points / Plane Strain Curv

These are the options that are appropriate to the highlighted result type. They also indicate the options that were selected for a highlighted output request. See Table 3-1.

Composite Plate Opt

This databox appears for SOL 101 and 103 when the model contains pelements. Other options will be presented, such as Percent of Step Output and Intermediate Output Options depending on conditions listed in Table 3-2.

State Variables

To fully support submittal of Nastran with UDS for SOL 400, the specification of state variables is necessary. Use this section to specify the state variables.

Table 3-1

Output Request Descriptions

Output Request

Case Control Command or Bulk Data Entry

Description

Accelerations

ACCELERATION

Requests nodal accelerations.

Acoustic Intensity

INTENSITY

Requests acoustic intensity for external acoustics analysis (frequency response).

Acoustic Power

ACPOWER

Requests acoustic power radiated from surface for external acoustics analysis (frequency response).

Acoustic Field Point Mesh

ACFPMRESULT

Requests acoustic field point mesh results for external acoustics analysis (frequency response). You are given a list of all acoustic field point meshes defined and groups with nodes. Each one selected is translated into its own BEGIN AFPM section in the bulk data.

Acoustic Velocities

VELOCITY

Requests nodal velocities. This is for acoustic velocities at the node points of Field Point Mesh.

Applied Loads

OLOAD

Requests equivalent nodal applied loads.

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Chapter 3: Running an Analysis 483 Output Requests

Table 3-1

Output Request Descriptions (continued)

Output Request

Case Control Command or Bulk Data Entry

Description

Constraint Forces

SPCFORCES

Requests forces of single- point constraints.

Contact Results

BOUTPUT

Requests contact regions for output.

Displacements

DISPLACEMENT

Requests nodal displacements.

Eigenvectors

VECTOR

Requests nodal eigenvectors.

Element Forces

FORCE

Requests elemental forces.

Element Strain Energies

ESE

Requests elemental strain energies and energy densities. No options are allowed with this output request.

Element Strains

STRAIN

Requests elemental strains.

Element Stress Discontinuity

ELSDCON

Requests mesh stress discontinuities based on element stresses.

Element Stresses

STRESS

Requests elemental stresses.

Fatigue Life*

FATIGUE

Requests fatigue damage and life output

Grid Point Force Balance

GPFORCE

Requests grid point force balance at nodes. Sorting and format options are not allowed with this request.

Grid Point Stress Discontinuities

GPSDCON

Requests mesh stress discontinuities based on grid point stresses.

Grid Point Stresses

GPSTRESS

Requests stresses at grid points.

MultiPoint Constraint Forces

MPCFORCES

Requests forces of multipoint constraints (for versions 68 or higher).

Nonlinear Applied Loads

NLLOAD

Requests equivalent nonlinear applied loads. Sorting and format options are not allowed with this request.

Nonlinear Stress

NLSTRESS

Requests the form and type of nonlinear element stress output.

Velocities VELOCITY Requests nodal velocities. * In order to run a successful MSC Nastran Embedded Fatigue analysis, an S-N or ε-N constitutive model (or both) must be defined for the elements of interest (see Stress-Life (SN) and Strain Life (eN), Spot Weld (Top and Bottom Sheet), Seam Weld (Stiff and Flexible), 92). An output request for fatigue life must be made as described here. An fatigue analysis must be turned ON when setting up the analysis (see Solution Parameters, 312 for Linear Static, Normal Modes, Transient Response, or Frequency Response). And cyclic loading must be defined (see Subcase Select, 515). For more detail on how to set up and perform a fatigue, please see the MSC Nastran Fatigue Analysis User’s Guidefor time domain SOLutions 101/103/112 or MSC Nastran Embedded Vibration Fatigue User’s Guide for frequency domain solutions SOLs 108 and 111. For details on the FATIGUE case control, please see the FATIGUE (Case) (p. 333) in the MSC Nastran Quick Reference Guide.

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Table 3-2

Options Sorting

Output Request Form Options

Label By Node/

Case Control or Bulk Data Options

Groups

Multiple Select Allowed

SORT1

Elements

No

Output is presented as tabular listing of nodes/elements for each load, frequency, eigenvalue, or time.

By Frequency/ SORT2

Elements

No

Output is presented as tabular listing of frequency or time for each node or element.

Element

Time Format

Tensor

Element Points

Main Index

Descriptions

Rectangular

REAL

Elements

No

Requests real and imaginary format for complex output.

Polar

PHASE

Elements

No

Requests magnitude and phase format for complex output.

Von Mises

VONMISES

Elements

No

Requests von Mises stresses or strains.

Maximum Shear

MAXS

Elements

No

Requests Maximum shear or Octahedral stresses or strains.

Cubic

CUBIC

Elements

No

Requests QUAD4 stresses or strains at the corner grid points as well as the center using the strain gage approach with cubic bending correction.

Corner

CORNER

Elements

No

Requests QUAD4 stresses or strains at the corner grid points as well as the center.

Center

CENTER

Elements

No

Requests QUAD4 stresses or strains at the center only.

Strain Gage

SGAGE

Elements

No

Requests QUAD4 stresses or strains at the corner grid points as well as the center using the strain gage approach.

Bilinear

BILIN

Elements

No

Requests QUAD4 stresses or strains at the corner grid points as well as the center using bilinear extrapolation.

Chapter 3: Running an Analysis 485 Output Requests

Table 3-2

Options Composite Plate Options

Composite Plate Options

Plate Strain Options

Main Index

Output Request Form Options (continued)

Label

Case Control or Bulk Data Options

Groups

Multiple Select Allowed

Descriptions

Element Stresses

NOCOMPS= -1, LSTRN = 0 in Bulk Data

Elements: Surfaces

No

Composite element ply stresses and failure indices are suppressed. Element stresses for the equivalent homogeneous element are output.

Ply Stresses

NOCOMPS=1,LS Elements: TRN = 0 in Bulk Surfaces Data

No

Composite element ply stresses and failure indices are output. Model should contain PCOMP entry defining composites.

Ply Strains

NOCOMPS=1,LS Elements: TRN = 1 in Bulk Surfaces Data

No

Composite element ply strains and failure indices are output. Model should contain PCOMP entry defining composites.

Ply Element Stresses

NOCOMPS=0,LS Elements: TRN=0 in Bulk Surfaces Data

No

Composite element ply stresses and failure indices as well as Element stresses for the equivalent homogeneous element are output. Model should contain PCOMP entry defining composites.

Element and Ply Strains

NOCOMPS=0,LS Elements: Surfaces TRN=1 in Bulk Data

No

Composite element ply strains and failure indices as well as Element stresses for the equivalent homogeneous element are output. Model should contain PCOMP entry defining composites.

Plane Curv.

STRCUR

Elements: Surfaces

No

This option is available for Element Strains output requests only. Strains and curvatures are output at the reference plane for plate elements.

Fiber

FIBER

Elements: Surfaces

No

This option is available for Element Strains output requests only. Strains at locations Z1 and Z2 (specified under element properties) are output at the reference plane for plate elements.

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Table 3-2

Options Sorting

Output Request Form Options (continued)

Label

Case Control or Bulk Data Options

Groups

Multiple Select Allowed

Descriptions

By Node /Element

SORT1

Nodes Elements

No

Output is presented as tabular listing of nodes/elements for each load, frequency, eigenvalue, or time.

By Frequency/ Time

SORT2

Nodes Elements

No

Output is presented as tabular listing of frequency or time for each node or element.

By Event

SORT2

Elements

No

For fatigue analysis only - lists results or each load event for each element in output file (F06), otherwise (SORT1) the list is for all elements of each event.

Rectangular

REAL

Nodes

No

Requests real and imaginary format for complex output.

Polar

PHASE

Nodes

No

Requests magnitude and phase format for complex output.

Output Coordinate

Coord

COORD CID

Elements:

Yes

Selects the output coordinate frame for grid point stress output. Coord 0 is the basic coordinate frame.

Volume Output

Both

Blank

Elements: Volumes

Yes

Requests direct stress, principal stresses, direction cosines, mean pressure stress and von Mises equivalent stresses to be output.

Principal

PRINCIPAL

Elements: Volumes

Yes

Requests principal stresses, direction cosines, mean pressure stress and von Mises equivalent stresses to be output.

Direct

DIRECT

Elements: Volumes

Yes

Requests direct stress, mean pressure stress and von Mises equivalent stresses to be output.

Format

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Surfaces, Volumes

Chapter 3: Running an Analysis 487 Output Requests

Table 3-2

Output Request Form Options (continued)

Options

Label

Case Control or Bulk Data Options

Groups

Multiple Select Allowed

Descriptions

Fiber

All

FIBER, ALL

Elements: Surfaces

Yes

Specifies that grid point stresses will be output at all fibre locations, that is at Z1, Z2 and the reference plane. Z1 and Z2 distances are specified as element properties (default Z1=-thickness/2, Z2= +thickness/2).

Fiber

Mid

FIBER, MID

Elements: Surfaces

Yes

Specifies that grid point stresses will be output at the reference plane.

Z1

FIBER, Z1

Elements: Surfaces

Yes

Specifies that grid point stresses will be output at distance Z1 from the reference plane (default Z1=thickness/2).

Z2

FIBER, Z2

Elements: Surfaces

Yes

Specifies that grid point stresses will be output at distance Z2 from the reference plane (default Z2=+thickness/2).

X1

NORMAL X1

Elements: Surfaces,

Yes

Specifies the x-axis of the output coordinate frame to be the reference direction for the positive fiber and shear stress output.

X2

NORMAL X2

Elements: Surfaces

Yes

Specifies the y-axis of the output coordinate frame to be the reference direction for the positive fiber and shear stress output.

X3

NORMAL X3

Elements: Surfaces

Yes

Specifies the z-axis of the output coordinate frame to be the reference direction for the positive fiber and shear stress output.

Normal

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Table 3-2

Output Request Form Options (continued)

Options Method

Label

Case Control or Bulk Data Options

Groups

Multiple Select Allowed

Descriptions

Topological

TOPOLOGI-CAL Elements: Surfaces

Yes

Specifies the topological method for calculating average grid point stresses. This is the default.

Geometric

GEOMETRIC

Elements: Surfaces

Yes

Specifies the geometric interpolation method for calculating average grid point stresses. This method should be used when there are large differences in slope between adjacent elements.

X-axis of Basic Coord

X1

AXIS, X1

Elements: Surfaces

Yes

Specifies that the x-axis of the output coordinate frame should be used as the x-output axis and the local x-axis when geometric interpolation method is used.

X-axis of Basic Coord

X2

AXIS, X2

Elements: Surfaces

Yes

Specifies that the y-axis of the output coordinate frame should be used as the x-output axis and the local x-axis when geometric interpolation method is used.

X3

AXIS, X3

Elements: Surfaces

Yes

Specifies that the z-axis of the output coordinate frame should be used as the x-output axis and the local x-axis when geometric interpolation method is used.

Break

BREAK

Elements: Surfaces

Yes

Treats multiple element intersections as stress discontinuities in the geometric interpolation method.

No Break

NOBREAK

Elements: Surfaces

Yes

Does not treat multiple element intersections as stress discontinuities in the geometric interpolation method.

0.0

TOL=0.0

Elements: Surfaces

Yes

Defines the tolerance to be used for interelement slope differences. Slopes beyond this tolerance will signify discontinuous stresses.

Branch

Tolerance

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Chapter 3: Running an Analysis 489 Output Requests

Table 3-2

Output Request Form Options (continued)

Options

Label

Case Control or Bulk Data Options

Groups

Multiple Select Allowed

Descriptions

Percent of Step Output

100

NOi Field of TSTEP and TSTEPNL entry

All

Once per subcase

An integer ‘n’ that specifies the percentage of intermediate outputs to be presented for transient and nonlinear transient analyses.

Adaptive Cycle Output Interval

0

BY = n on OUTPUT Bulk Data entry

p-elements Once per subcase

An integer ‘n’ that requests intermediate outputs for each nth adaptive cycle. For n=0, only the last adaptive cycle results are output. This is available for SOLs 101 and 103 for versions 68 and higher.

Intermediate Yes Output Options

INTOUT field of NLPARM Bulk Data entry

All

Once per subcase

Intermediate outputs are requested for every computed load increment. Applicable for nonlinear static solution type only.

No

INTOUT field of NLPARM Bulk Data entry

All

Once per subcase

Intermediate outputs are requested for the last load of the subcase. Applicable for nonlinear static solution type only.

All

INTOUT field of NLPARM Bulk Data entry

All

Once per subcase

Intermediate outputs are requested for every computed and userspecified load increment. Applicable for nonlinear static solution type only.

N/A

Specifies PLOT option instead of PRINT on the Case Control Output request entry.

All

Yes

Print to the .f06 file is suppressed for the result type when this is selected.

Suppress Print for Result Type

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Table 3-2

Options Output Device Options

Output Request Form Options (continued)

Label

Case Control or Bulk Data Options

Groups

Multiple Select Allowed

Print

Specifies PRINT on a Case Control request entry, e.g. DISPL.

All

Yes

The printer will be the output medium for the .f06 file.

Punch

Specifies PUNCH All on a Case Control request entry, e.g. DISPL.

Yes

The punch file will be the output medium.

Both

Specifies both PRINT and PUNCH.

Yes

The printer and punch file will be the output medium.

All

State Variables

Type of include data Select Property Set(s) Select Elements to Exclude Additional Output FIle Formats

Descriptions

To fully support submittal of Nastran with UDS for SOL 400, the specification of state variables is necessary. Use this section to specify the state variables. Number of State Variables

Text box to enter the number of state variables.

State Variable Name

Text box to enter the name of the selected state variable.

Data

Spreadsheet displaying the state variables and their names.

These four are used for FATIGUE output requests only. Property Sets: The first list box allows you to select property sets that have stress-life or strain-life material constitutive models associated with them for inclusion in a fatigue analysis. These will be written to a standard Nastran SET4 entry. Groups: The first list box allows you to groups containing elements for inclusion in a fatigue analysis. These will be written to a standard Nastran SET1 entry. The second list box allows you to select individual elements to exclude from a fatigue analysis as defined in a Patran group. These are written to a SET1 entry. Both the SET4 and SET1 are then referenced on a FTGDEF bulk data entry that is called out by the FATIGUE case control output request. Additional output file types besides the standard MSC Nastran MASTER/DBALL files can be requested such as CSV file, a Patran results file (FEF) or an MSC Fatigue FER file. This is done directly on the FATIGUE case control.

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Chapter 3: Running an Analysis 491 Output Requests

Edit Output Requests Form Use this form to edit the outputs request associated with selected subcases. To access this form, select the Output Requests button on the Subcases form with the Action set to Global Data.

Select Group(s)/SET

Inactive (greyed out) until a subcase label (column 1) is selected. When this button is selected, the top half of the form will become inactive, and the default output request function (named user_change_default_out_req) will be called. This will load user defined defaults or the system defined defaults if user ones do not exist.

Options

Selecting the Default button when a single cell is selected resets the selected output request to its default setting.

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Row Labels

The row labels for the spreadsheet are the selected subcases from the parent form. The Output Requests for each subcase are stored in cells of the spreadsheet.

Clear Cell(s)

Clears the selected cells. You can select individual cells, multiple cells in a column, entire columns, or entire rows.

Cancel

Closes the form and saves the selected changes. To apply the new output requests, you must select Apply on the parent Subcases/Global Data form.

Parameter Name

Description

Select Group(s)/SET

Inactive (greyed out) until a subcase label (column 1) is selected. When this button is selected, the top half of the form will become inactive, and the default output request function (named user_change_default_out_req) will be called. This will load user defined defaults or the system defined defaults if user ones do not exist.

Options

Selecting the Default button when a single cell is selected resets the selected output request to its default setting.

Row Labels

The row labels for the spreadsheet are the selected subcases from the parent form. The Output Requests for each subcase are stored in cells of the spreadsheet.

Clear Cell(s)

Clears the selected cells. You can select individual cells, multiple cells in a column, entire columns, or entire rows.

Cancel

Closes the form and saves the selected changes. To apply the new output requests, you must select Apply on the parent Subcases/Global Data form.

Notes: • The Edit Output Requests form opens with focus in the first result type of the first subcase. • The top half of the Edit Output Requests form is similar to the Advanced Output Request form. • The spreadsheet column labels are the result types for the current solution type. • Putting focus in a cell causes the top half of the form to reflect the current setting, just like the

current advanced output request form. This means that the databox RESULT TYPE: gets updated with the result type of the currently selected cell. The OUTPUT REQUESTS: databox is also updated to show the actual content of the cell. • If a cell is initially empty, selecting it will cause the top half of the form to display the

appropriate default setting for the selected result type (i.e., column).

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Chapter 3: Running an Analysis 493 Output Requests

• Selecting a column header will allow you to change all subcase output requests of a particular

type. The top half of the Edit Output Requests form will set to the default request of the particular result type. • When you select a set of contiguous column cells, the top half of the form will configure to the

upper most selected cell. • You cannot select multiple columns.

Default Output Request Information In order to make use of this feature you need to create a PCL file that contains the function user_change_default_out_req which overwrites the existing default file in Patran. This new PCL file needs to be compiled and then the resulting library (.plb) needs to be loaded into Patran. This can be done using the p3midilog.pcl or the p3epilog.pcl file. The user_change_default_out_req function makes use of the mscn_user_add_out_req and the mscn_user_del_out_req functions to add and delete default Output Request types. These two functions are defined as follows:

mscn_user_add_out_req

(or_num, or_value)

Description: This function adds either a specified version or a default version of an Output Request type to the list of default Output Requests. Input: INTEGER or_num The OR number of the output request type to add (See Table 3-3). STRING or_value The value of the selected output request type. Blank implies the default value.

mscn_user_del_out_req

(or_num)

Description: This function deletes the specified Output Request type from the list of default Output Requests. Input: INTEGER or_num The OR number of the Output Request type to delete (See Table 3-3). Code Sample

FUNTION user_change_default_out_req(sol_seq) INTEGER sol_seq IF (sol_seq == 101 || sol_seq == 106) THEN /* This will add this version of the Output Request type to the list of default */

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/* Output Requests for solution 101 and 106. */ mscn_user_add_out_req (4,”MPCFORCES(SORT2,REAL)=ALL FEM”) /* This will add the default version of these Output Request types from the list */ /* of default Output Requests for solution 101 and 106. */ mscn_user_add_out_req (10,“ ”) mscn_user_add_out_req (6,“ ”) /* This will delete these Output Request types from the list of default */ /* Output Requests for solution 101 and 106. */ mscn_user_del_out_req (1) mscn_user_del_out_req (2) mscn_user_del_out_req (3) END IF END FUNCTION The following is a table that shows the current predefined default Output Requests (those marked with an X) and the allowed options (those marked with an O) for the various solution sequences. Table 3-3 SOL Seq.

Result ID Number Result ID (or Number)

1

2

3

4

5

6

101

x

x

x

o

o

o

103

o

o

x

o

o

105

x

o

x

o

o

o

106

x

x

x

o

o

107

o

o

x

o

o

108

x

o

x

o

o

o

109

x

o

x

o

o

o

110

o

o

x

o

o

111

x

o

x

o

o

o

112

x

o

x

o

o

o

114

x

x

x

o

o

o

115

o

o

x

o

o

129

x

o

x

153

o

o

o

159

o

o

o

o

7

8

9

10 11 12 13 14 15 16 17 18 19 20 21

o

o

o

o

o

o

o

o o

o o

o

o o

o

o

o

o

o

o

o

o

o

o

o

o

o

o

o

o

o

o

o

o

o

x

x

o

o

o

o

o

o

o

o

o

o

x

x

o

o

o

x

x

o

o

o o

o

o o

o

o x

x x

600

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o o

o

400 700

x

x

o

o o

25

x

o

o

o

o

o o

o

24

x

o o

o

23

x

o o

o

22

x

o

x

o

o

o

o

o

o

o

x

Chapter 3: Running an Analysis 495 Output Requests

1 = Displacement, 2 = stress, 3 = spcforces, 4 = mpcforces, 5 = forces, 6 = oload, 7 = nlload, 8 = ese, 9 = strain, 10 = gpstress, 11 = velocity, 12 = acceleration, 13 = gpforce, 14 = gpsdcon, 15 = elsdcon, 16 = vector, 17 = thermal, 18 = flux, 19 = ht_oload, 20 = ht_spcforces, 21 =enthalpy, 22 = hdot, 23=nlstress, 24=bccontact, 25=fatigue

OR #

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Default Value 1

DISPLACEMENT(SORT1,REAL)=All FEM

2

STRESS(SORT1,REAL,VONMISES,BILIN)=All FEM;PARAM,NOCOMPS,-1

3

SPCFORCES(SORT1,REAL)=All FEM

4

MPCFORCES(SORT1,REAL)=All FEM

5

FORCE(SORT1,REAL,BILIN)=All FEM

6

OLOAD(SORT1,REAL)=All FEM

7

NLLOAD=All FEM

8

ESE=All FEM

9

STRAIN(SORT1,REAL,VONMISES,STRCUR,BILIN)=All FEM

10

GPSTRESS=All FEM; VOLUME # SET,PRINCIPAL,SYSTEM Coord 0; SURFACE # SET #,FIBRE ALL,SYSTEM Coord 0, AXIS X1,NORMAL R, TOPOLOGICAL,BRANCH BREAK

11

VELOCITY(SORT1,REAL)=All FEM

12

ACCELERATION(SORT1,REAL)=All FEM

13

GPFORCE=All FEM

14

GPSDCON=All FEM; VOLUME # SET #,PRINCIPAL,SYSTEM Coord 0; SURFACE # SET #,FIBRE ALL,SYSTEM Coord 0, AXIS X1,NORMAL R, TOPOLOGICAL 0.,BRANCH BREAK

15

ELSDCON=All FEM; VOLUME # SET #,PRINCIPAL,SYSTEM Coord 0; SURFACE # SET #,FIBRE ALL,SYSTEM Coord 0, AXIS X1,NORMAL R, TOPOLOGICAL 0.,BRANCH BREAK

16

VECTOR(SORT1,REAL)=All FEM

17

THERMAL=(SORT1,PRINT)=All FEM

18

FLUX(SORT1,PRINT)=All FEM

19

OLOAD(SORT1,PRINT)=All FEM

20

SPCFORCES(SORT1,PRINT)=All FEM

21

ENTHALPY(SORT1,PRINT)=All FEM

22

HDOT(SORT1,PRINT)=All FEM

23

NLSTRESS

24

BCCONTACT

25

FATIGUE

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Note:

In SOL 109, 112 & 159 will have SORT2 as the default in some versions of Patran.

Subcases Direct Text Input This form is used to directly enter entries into the Case Control section for the defined subcase.

Parameter Name

Description

FMS Write To Input Deck

Directly entered entries may potentially conflict with those created by the interface. Writing these entries to the file can be controlled with this toggle.

OK

Saves the current setting and data for the four sections and closes the form.

Clear

Clears the current form.

Reset

Resets the form back to the data values it had at the last OK.

Cancel

Resets all four forms back to its previous value and closes the form.

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Chapter 3: Running an Analysis 497 Output Requests

SOL 600 Output Requests This subform defines the output data for a SOL 600 analysis subcase

Parameter Name

Description

Echo Marc Input File

Produces an echo of the input file.

Results in Marc Print File

Writes results to a print file.

Results (POST) File Options • Increments between Writing Results

Defines the number of increments between writing results to the MSC Nastran results file after the first increment of the analysis. The default is one (1) for every increment. Note: You can select a fixed number of increments of output on the subcase parameters-load increments parameters form.

• Select Nodal Results...

Brings up a subform for selecting nodal results

• Select Element Results...

Brings up a subform for selecting elemental results.

Output requests for all subcases.

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Select Nodal Results

This subform controls which nodal result quantities are returned from the analysis.

Parameter Name

Description

Available Result Types

Lists all of the available result types for the analysis. The numbers in parentheses are the MSC.Marc POST code numbers, that will be specified on the MARCOUT entry

Selected Result Types

Shows the set of result types that have been selected to be returned in the analysis.

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Chapter 3: Running an Analysis 499 Output Requests

The following table shows the post codes that may be selected for a SOL 600 structural nonlinear analysis. Nodal Result

Default(?)

DISPLACEMENT

1

YES

ROTATION

2

no

EXTERNAL FORCE

3

no

EXTERNAL MOMENT

4

no

REACTION FORCE

5

YES

REACTION MOMENT

6

no

PORE PRESSURE

23

no

VELOCITY

28

no

ROTATIONAL VELOCITY

29

no

ACCELERATION

30

no

ROTATIONAL ACCELERATION

31

no

MODAL MASS

32

no

ROTATION MODAL MASS

33

no

CONTACT NORMAL STRESS

34

no

CONTACT NORMAL FORCE

35

no

FRICTION STRESS

36

no

FRICTION FORCE

37

no

CONTACT STATUS

38

no

CONTACT TOUCHED BODY

39

no

HERRMANN VARIABLE

40

no

POST CODE, No. -11

-11 thru -16

no

POST CODE, No. -22

-21 thru -23

no

POST CODE, No. -31

-31

no

POST CODE, No. -41

-41

no

POST CODE, No. -51

-51

no

Note:

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Postcode

The POST CODE (Analysis (p. 427) in the Patran Reference Manual.

Analysis Type

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Available Jobs

List of already existing jobs.

Job Name

Name assigned to current translation job. This job name will be used as the base file name for the message file.

Entity Selection...

Activates a subordinate Entity Selection form which allows the user to specify the specific entry types to be read. Also defines ID offset values to be used during import.

Select Input File...

Activates a subordinate File Select form which allows the user to specify the NASTRAN input file to be translated.

Chapter 5: Read Input File 623 Review of Read Input File Form

Entity Selection Form This subordinate form appears when the Entity Selection button is selected on the Analysis form and Read Input File is the selected Action. It allows the user to specify which MSC Nastran entity types to import.

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Patran Interface to MSC Nastran Preference Guide Review of Read Input File Form

Parameter Name

Description

Entity Packets

Highlighted entity types will be imported.

Define Offset...

Activates the form to define ID offsets.

Create Prop. & Matl. Groups

Select this button to create groups based on property sets and materials.

Retrieve Names From Comments

Selecting this toggle will tell Patran to attempt to retrieve the names of properties and materials from the comments in the input file. This only applies to material and element properties names.

The following table shows the relation between the entity types listed above and the actual MSC Nastran entry types effected. If an entity type is filtered out, it is treated as if those entries did not exist in the original input file. Entity Type

MSC Nastran Cards

Nodes

GRID, GRDSET, SPOINT

Elements

BAROR, BEAMOR, CBAR, CBEAM, CBEND, CDAMP1, CDAMP2, CDAMP3, CDAMP4, CELAS1, CELAS2, CELAS3, CELAS4, CGAP, CHEXA, CMASS1, CMASS2, CMASS3, CMASS4, CONM1, CONM2, CONROD, CPENTA, CQUAD4, CQUAD8, CQUADR, CROD, CSHEAR, CTETRA, CTRIA3, CTRIA6, CTRIAR, CTRIAX6, CTUBE, CVISC, PLOTEL

Material Properties

MAT1, MAT2, MAT3, MAT8, MAT9

Element Properties

PBAR, PBCOMP, PBEAM, PBEND, PCOMP, PDAMP, PELAS, PGAP, PMASS, PROD, PSHEAR, PSHELL, PSOLID, PTUBE, PVISC

Coordinate Frames

CORD1C, CORD1R, CORD1S, CORD2C, CORD2R, CORD2S

Load Sets

FORCE, GRAV,MOMENT, PLOAD1, PLOAD2, PLOAD4, PLOADX1, RFORCE, TEMP, TEMPP1, TEMPRB, SPC, SPC1, SPCD

Subcases

LOAD, SPCADD, Case Control Section

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Chapter 5: Read Input File 625 Review of Read Input File Form

Entity Type

MSC Nastran Cards

MPC Data

MPC, RBAR, RBE1, RBE2, RBE3, RROD, RSPLINE, RTRPLT

Comment Lines

All items starting with a "$" are added to the imported Job as Direct Text Input. Also unrecognized entries are also imported. Turning this selection OFF will not import any entries begining with a "$", however unrecognized entries will still be imported. To disable import of both the comment lines and the unrecognized entries, use the Define Offsets Form and set the Comment Lines Offset/Maximum to a negative number. Be default only 1000 comment lines and 1000 unrecognized entiries will be imported. The system environment variable PATRAN_DTI_LINE_LIMIT, or a settings.pcl entry pref_env_set_integer("patran_dti_line_limit", ) can be set, or the value can be changed on the Define Offsets Form. Setting it to zero (0) or AUTO will cause all comments and unrecognized items to be imported. Use caution when doing this as many input decks have thousands of comment lines and this could cause unnecessary bloating of the database and poor performance access to Direct Text Input form.

It should be noted that since the GRID entry is controlled with the Nodes filter, the grid.ps load set with the permanent single point constraint data will also be controlled by the Nodes filter.

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Patran Interface to MSC Nastran Preference Guide Review of Read Input File Form

Define Offsets Form This subordinate form appears when the Define Offsets button is selected on the Entity Selection form. It allows the user to specify the ID offsets used when reading a MSC Nastran input file.

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Chapter 5: Read Input File 627 Review of Read Input File Form

Parameter Name

Description

Automatic Offset

If selected, the value in the Maximum column will be used as the offset for the selected rows.

Minimum and Maximum IDs

Minimum and Maximum IDs currently found in the Patran database.

New ID

ID offset value to be used during import. The new ID value will be the ID found in the NASTRAN input file plus this offset value.

All offset data boxes can be selected at once by selecting this column header.

All references made in the input file will also be offset. If a node references a particular CID as its analysis frame, then the reference will be offset as well. If the coordinate frame is defined in the same input file, the proper references should be maintained. The preference will be properly maintained. If the coordinate frame existed in the file prior to the import, then it needs to be the offset CID. If a coordinate frame with that CID is not found in the database, an error message will be issued. To determine which offset effects a particular MSC Nastran entry type, refer to the table in the previous section. For Patran entities identified by integer IDs (nodes, elements, coordinate frames, and MPCs), the offset value is simply added to the MSC Nastran ID to generate the Patran ID. For Patran entities identified by text names (materials, element properties, load sets, and load cases), the offset value is first added to the MSC ⁄ Nastran ID. The new integer value is then used to generate the Patran name per the naming conventions described in later sections.

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Patran Interface to MSC Nastran Preference Guide Review of Read Input File Form

Selection of Input File This subordinate form appears when the Select Input File button is selected on the Analysis form and Read Input File is the selected Action. It allows the user to specify which MSC Nastran input file to translate.

Summary Data Form This form appears after the import of the NASTRAN input file has completed. It displays the number of entities imported correctly, imported with warnings, or not imported due to errors. These figures reflect the number of Patran entities created. In some cases, there is not a one-to-one relation between the original MSC Nastran entities and the generated Patran entities. For example, when material orientations on several CQUAD4s are defined using references to varying MCIDs while still referencing the same PID, Patran needs to create a unique property set for each different MCID reference. When the OK button is selected, the newly imported data will be committed to the Patran database, and can not be undone. If there is any question as to whether or not this import was desired, review the

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Chapter 5: Read Input File 629 Review of Read Input File Form

graphics data prior to selecting OK on this form. If the import was not correct, select the undo button on the main menu bar before selecting OK on this form.

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Patran Interface to MSC Nastran Preference Guide Review of Read Input File Form

Reject Card Form During import of the NASTRAN input file, some entries types might not be understood by Patran. Those entries are brought into Patran in the direct text input data boxes. Selecting the Reject Cards button on the Summary Data form will bring up this Reject Card Form. You can review these entries here.

Only entry types not supported by Patran are sent to the reject entry blocks. (This includes comments.) Cards which are otherwise recognized, but can not be imported due to syntax or invalid data errors are not sent to the reject blocks. The rejected entries will have no characters in front of the command name. Commands preceded by the character $> are used by the MSC/AMS product to allow processing of comment lines. Note:

Main Index

Rejected cards are placed in the Direct Text Input (DTI) text boxes. If you turn ON the ability to write DTI into the various portions of the MSC Nastran input deck, the rejected cards will be placed back into the input deck when it is written out again.

Chapter 5: Read Input File 631 Data Translated from the NASTRAN Input File

5.2

Data Translated from the NASTRAN Input File The following sections describe which specific MSC Nastran entry types can currently be read into Patran. The MSC Nastran entries described in this document are the only entries read when importing a NASTRAN input file into Patran. All non-supported entries will be sent to the appropriate Direct Text Input data box for this job. When errors occur during the import of a supported entry type, the entry being processed may or may not be imported, depending on the severity of the problem encountered. An error message will be presented regardless of whether or not the offending entry is actually imported. Any references from supported entries to entries that were not imported (either due to not being a supported entry type or due to serious import errors) will still be attempted. If this reference is required in Patran for the entry currently being processed, it too will fail to import. For example, if there is a serious error on a GRID entry which causes it to not imported, then all elements attached to that GRID will also fail to import. Partial Decks This Patran function can read incomplete MSC Nastran files (except where explicitly noted). However, if the BEGIN BULK command is missing, the program can get confused when trying to determine if a particular entry belongs to the case control or bulk data. If you experience any difficulties importing a file that does not have a BEGIN BULK command, add one to the top of the file. This should avoid any such confusion. Unrecognized Data Data in the MSC Nastran input deck that is not recognized by Patran, including comments are placed in the reject file. These rejected cards are also placed into the Direct Text Input (DTI) text boxes. If you turn ON the ability to write DTI into the various portions of the MSC Nastran input deck, the rejected cards will be placed back into the input deck when it is written out again. Note that decks with large amounts of rejected cards and comments may place an unacceptable amount of data in these text boxes. If this is the case, you can limit the amount of data by setting the environment variable:

Coordinate Systems The following coordinate system definitions can be read into Patran. Command CORD1C CORD1R CORD1S

Main Index

Comments References to the GRIDs on these entries are lost. The locations of the referenced GRIDs are extracted, and those locations are used to create the Patran definition.

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Patran Interface to MSC Nastran Preference Guide Data Translated from the NASTRAN Input File

Command CORD2C CORD2R CORD2S

Comments References to RIDs are lost. The specified locations are converted to global cartesian for use in the Patran definitions. The original B and C points are not retained. Their values are recomputed when a new NASTRAN input file is created. The definition will be equivalent, but not identical.

Referential Integrity Coordinate systems and GRIDs which are referenced as part of a CORD definition must be in the same input file. If these are not found in the input file, the definition will be rejected. References to coordinate frames other than for new coordinate frame definitions can be resolved with coordinate frames previously found in the Patran database. Chaining Due to limitations in the Patran definitions of coordinate systems, chained definitions (definitions based on other coordinate systems or grids) are modified during import. The resulting definitions are equivalent in global space, but are based on global cartesian coordinates rather than GRID references or coordinate locations in other systems. This change is carried through when a new NASTRAN input file is created. All coordinate systems will be created using CORD2 type definitions, and they will all reference global cartesian coordinates. These definitions will be different from, but equivalent to, the original definitions.

Grids and SPOINTs The MSC Nastran GRID entry is read fully, except the SEID field. The CD and CP references are both maintained. The PS data is used to create a constraint set. The details of the created load set are defined in the load set import section. GRDSET data is merged into the GRID data during import. The data will be retained, but will appear directly on the GRID entry when a new NASTRAN input file is generated. SPOINTs SPOINTs are treated as GRIDs at the global origin. They are assumed to have their GRID CD and CP fields set to the basic system, and their PS field is set to permanently constrain degrees-of-freedom 2 through 6. Referential Integrity Coordinate frames referenced in the CP field must exist in the same input file. Coordinate frames referenced on the CD field can exist in either the same input file, or the Patran database prior to the import.

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Chapter 5: Read Input File 633 Data Translated from the NASTRAN Input File

Elements and Element Properties The following MSC Nastran elements and element properties can be read into Patran. Element CBAR

Property PBAR

Property Set Name pbar.

Comments Orientation and offset vectors are re-defined in global cartesian during import. (See BAROR comments below.)

PBARL

pbarl.

CBARAO

New property sets are created for each occurrence of a CBAR entry referenced by a CBARAO entry

CBEAM

Orientation and offset vectors are re-defined in global cartesian during import. (See BEAMOR comments below.) PBEAM

pbeam.

PBEAML

pbeaml.

PBCOMP

pbcomp.

The MSC Nastran documentation describes how the section data is used to create a complete set of lumped areas. The data imported into Patran is fully expanded, and therefore, is different from the data in the original input file. This definition is, however, fully equivalent to the original. The SO field is not currently supported. A YES is provided automatically when a new NASTRAN input file is created. Only the lumped areas definition is understood, If a uniform cross section is defined here, it will be converted to a lumped area definition, but no lumped areas will be defined.

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Patran Interface to MSC Nastran Preference Guide Data Translated from the NASTRAN Input File

Element

Property

Property Set Name

CBEND

Comments Patran only understands the GEOM = 1 orientation data. If other definitions are found, a vector will be computed to convert the definition to the GEOM = 1 format. If a GRID was referenced for GEOM other than 1, that reference will be lost. For the same reasons, the THETAB and RB data will also be lost since that data is not used for GEOM = 1 definitions. Orientation and offset vectors are re-defined in global cartesian during import.

PBEND

CBUSH

PBUSH

pbend_g.

If standard cross section properties are found on the PBEND entry

pbend_p.

If the alternate format of the PBEND is used to define a pipe cross section.

pbush. pbush_g.

CDAMP1

PBUSHT

pbusht_1D.

PDAMP

pdamp.

For dampers connecting 2 GRIDs.

pdamp_g.

For grounded dampers attached to a single GRID.

cdamp2

For dampers connecting 2 GRIDs.

cdamp2_g

For grounded dampers attached to a single GRID.

CDAMP2 CDAMP3

PDAMP

Treated identical to the CDAMP1 and CDAMP2 elements with the degree-of-freedom fields set to 1 (UX).

CDAMP4 CELAS1

PELAS

CELAS2 CELAS3

pelas.

For springs connecting 2 GRIDs.

pelas_g.

For grounded springs attached to a single GRID.

celas2

For springs connecting 2 GRIDs.

celas2_g

For grounded springs attached to a single GRID.

PELAS

Treated identical to the CELAS1 and CELAS2 elements with the degree-of-freedom fields set to 1 (UX).

CELAS4 CGAP

Orientation and offset vectors are re-defined in global cartesian during import. PGAP

CHBDYG

pgap.

For non-adaptive definitions on the PGAP entry.

pgap_a.

For adaptive definitions on the PGAP entry.

PHBDY

Note: The BDYOR command that may contain default values for CHBDY elements is not currently supported.

CHBDYP CHEXA

Main Index

The grounded form of the PBUSH

PSOLID

psolid.

Chapter 5: Read Input File 635 Data Translated from the NASTRAN Input File

Element CMASS1

Property PMASS

CMASS2 CMASS3

Property Set Name

Comments

pmass.

For masses connecting 2 GRIDs.

pmass_g.

For masses attached to a single GRID.

cmass2

For masses connecting 2 GRIDs.

cmass2_g

For masses attached to a single GRID.

PMASS

Treated identical to the CMASS1 and CMASS2 elements with the degree-of-freedom fields set to 1 (UX).

CMASS4 CONM1

conm1

CONM2

conm2

CONROD

conrod

CPENTA

PSOLID

psolid.

CQUAD4

PSHELL

pshell.

(See PSHELL comments below.)

PCOMP

pcomp.

A new material named pcomp. will be created and referenced. The SB and FT fields are currently not read.

CQUAD8

PSHELL

pshell.

(See PSHELL comments below.)

PCOMP

pcomp.

A new material named pcomp. will be created and referenced. The SB and FT fields are currently not read.

CQUADR

PSHELL

pshellr.

(See PSHELL comments below.)

PCOMP

pcompr.

A new material named pcomp. will be created and referenced. The SB and FT fields are currently not read.

CROD

PROD

prod.

CSHEAR

PSHEAR

pshear.

CTETRA

PSOLID

psolid.

CTRIA3

PSHELL

pshell.

(See PSHELL comments below.)

PCOMP

pcomp.

A new material named pcomp. will be created and referenced. The SB and FT fields are currently not read.

Main Index

636

Patran Interface to MSC Nastran Preference Guide Data Translated from the NASTRAN Input File

Element CTRIA6

Property

Property Set Name

Comments

PSHELL

pshell.

(See PSHELL comments below.)

PCOMP

pcomp.

A new material named pcomp. will be created and referenced. The SB and FT fields are currently not read.

CTRIAR

PSHELL

pshellr.

(See PSHELL comments below.)

PCOMP

pcompr.

A new material named pcomp. will be created and referenced. The SB and FT fields are currently not read.

CTRIAX6

ctriax6

CTUBE

PTUBE

ptube.

CVISC

PVISC

pvisc.

PLOTEL

Tapered tubes are converted to an equivalent constant section definition. Creates the connectivity only. These elements are not assigned to any property set region. PLOTEL entries will not be written when a new input file is created.

MBOLTU S

Defines a bolt in the form of an Overclosure MPC.

Higher order elements (CQUAD8, CTRIA6, CTRIAX6, CHEXA, CPENTA, CTETRA) will generate linear elements in Patran if none of the mid-edge nodes are specified. PSHELL Properties PSHELL properties can be imported as any one of five Patran property types. The MID1, MID2, MID3, 12I/T3, and TS/T property fields are used to determine which one to choose. If MID2 is -1 and MID3 is 0, then a Plane Strain property set is used. If MID2 and MID3 are both 0, then a Membrane property set is chosen. If MID1 and MID3 are 0, then a Bending property set is used. If MID1, MID2, and MID3 are all the same, and the MSC Nastran defaults are used for 12I/T3 and TS/T, then a Homogeneous property set is used. If all else fails, then an Equivalent Section property set is chosen. BAROR and BEAMOR Definitions The BAROR and BEAMOR data is merged onto the CBAR and CBEAM entries using the proper MSC Nastran conventions. The data is treated as if it had originally been defined on the CBAR and CBEAM entries. When a new NASTRAN input file is created, the data will remain with the CBAR and CBEAM entries. No BAROR or BEAMOR entries are generated.

Main Index

Chapter 5: Read Input File 637 Data Translated from the NASTRAN Input File

Fields If a field is required to store varying data, the field will have the same name as the property set, with the name of the specific property word appended to it. For example, if property set “pshell.101” has a varying thickness, the field will be named “pshell.101.Thickness”. Referential Integrity Nodes and coordinate frames referenced on elements or element properties must exist, but they do not need to be in the input file. They could also have been defined in the Patran database prior to the import. If a material is referenced, but can not be found, a new material with no properties will be created. A message will be issued indicating the creation of this material. If an element property set is referenced, but can not be found, a new property set with no properties will be created. A message will be issued indicating the creation of this property set. Set Name Extensions In some cases, the data found on the element can not be defined in Patran in a single property set. In those cases, multiple property sets will be created to define the distinct definitions. The table below defines extensions to the Property Set Names shown in the previous table. If the values on the specified field changes, a new property set with the indicated extension will be created. If all elements which reference a single PID can be stored in a single property set, then no extension will be added to the Property Set Name. Element CBAR

Field

Extension

PA

.pa

PB

.pb

SA

.sa

SB

.sb

PA

.pa

PB

.pb

CDAMP1, CDAMP2,

C1

.ca

CELAS1, CELAS2,

C2

.cb

CDAMP3, CDAMP4,

C1

.ca1

CELAS3, CELAS4,

C2

.cb1

CBEAM

Comments

CMASS1, CMASS2

CMASS3, CMASS4

Main Index

These are automatically treated as component 1 (X translation).

638

Patran Interface to MSC Nastran Preference Guide Data Translated from the NASTRAN Input File

Element

Field

Extension

CGAP, CONM1, CONM2

CID

.c

CONROD, CTRIAX6

MID

.m

CQUAD4, CQUAD8,

MCID

.c

Comments

CQUADR, CTRIA3, CTRIA6, CTRIAR

Materials The following MSC Nastran material definitions can be read into Patran. Material Type

Material Name

Comments

CREEP MAT1

mat1.

The MCSID field is not currently supported. If the G field is blank in the input file, the MSC Nastran default value will be filled in during import.

MATT1 MAT2

mat2.

The MCSID field is not currently supported.

MATT2 MAT3

mat3.

MATT3 MAT4 MATT4 MAT5 MATT5 MAT8

mat8.

MAT9

mat9.

MATT9 MATFTG

Main Index

Imported as fatigue Stress-Life (S-N) and/or Strain-Life (ε-N) constitutive models

Chapter 5: Read Input File 639 Data Translated from the NASTRAN Input File

MPCs The following MSC Nastran MPC and rigid element definitions can be read into Patran. Card Type MPC

MPC Type Explicit

Comments Unique MPC IDs will be assigned to these entities. Since Patran uses a slightly different basis MPC equation, the equation coefficients (Ai) will probably be scaled by a constant multiplier during import. The resulting equation will be equivalent, but not necessarily identical to the original definition in the NASTRAN input file.

RBAR

RBAR

RBE1

RBE1

RBE2

RBE2 Fixed

RBE3

RBE3

RROD

RROD

RSPLINE

RSPLINE

RSSCON

RSSCON

RTRPLT

RTRPLT MPCs in Patran are treated as elements and are not associated to load cases. As a result, all SUBCASE related data is lost. The MPCs are simply imported into the model and are no longer associated to a specific load case. MPCs can reference SPOINTs instead of GRIDs. If this is detected, the corresponding component field will be set to 1 (UX) to be consistent with the import of SPOINTs. The MPCADD command is not read since the MPCs are simply imported and no associated to a load case. The SID references on the MPC entry are also lost for the same reason. New MPC IDs are assigned to these elements during import.

Load Sets The following MSC Nastran Loads and Boundary Condition definitions can be read into Patran. Card Type

LBC Set Name

FORCE

force.

GRAV

grav.

MOMENT

moment.

Main Index

Comments

640

Patran Interface to MSC Nastran Preference Guide Data Translated from the NASTRAN Input File

Card Type

LBC Set Name

PLOAD1

pload1.

PLOAD2

pload2.

PLOAD4

pload4.

PLOADX1

ploadx1.

CONV

conv.

Comments Only PLOAD1s applied to the entire length of an element can be read. If a load is applied only to a portion of an element, the load will be ignored, and a message will be presented indicating the problem. Only pressure loads normal to the surface can be imported. If a surface traction is detected, it will be ignored, and a message will be presented indicating the problem.

PCONV CONVM

convm.

PCONVM QBDYi

qbdyi.

QVECT

qvect.

QVOL

qvol.

RADBC

radbc.

RADCAV

radcav.

Note: ELEAMB field is not supported by Patran. The ambient element is added to the application region.

rforce.

If the G point is not at the origin of the referenced CID, a new CID will be created and referenced.

RADM RADMT RFORCE

The METHOD field is not read. It is automatically set to 1 when writing a new file. SLOAD

sload.

TEMP

temp.

TEMPP1

tempp1.

Only the average temperature and effective linear gradient data fields are used. The specified temperatures at the Z1 and Z2 locations are ignored.

TEMPRB

temprb.

Only the average temperature and effective linear gradient data fields are used. The specified temperatures at the stress recovery locations are ignored.

grid#

grid.ps

SPC

spc.

SPCADD

Main Index

Chapter 5: Read Input File 641 Data Translated from the NASTRAN Input File

Card Type

LBC Set Name

SPC1

spc1.

SPCD

spcd.

Comments The required SPC or SPC1 entries for the same Degree-of-Freedom are removed from the load case when a SPCD is found. They will automatically be re-generated when a new input file is created.

VIEW VIEW3D Fields If a field is required to store varying data, the field will have the same name as the load set, with the name of the specific data word appended to it. For example, if load set “force.101” has a varying force magnitude, the field will be named “force.101.Force”. Load cases are created in Patran from the SUBCASE definitions in the NASTRAN input file. Load sets not referenced by a SUBCASE definition are created as load sets in Patran, but are not associated to a load case. Load sets defined above the first SUBCASE command, plus any permanent single point constraint sets from the GRID entries, are associated to all load cases created during this import. If there is no case control data, then load sets will be created, but they will not be assigned to any load cases. The SPCADD and LOAD entries are used in creating load cases in Patran, but the SID of these entries is lost. The SIDs on the individual SPCx, FORCE, MOMENT, GRAV, PLOADx, RFORCE, and TEMPx entries are used in creating the names of the load sets. The name for the created load cases is derived from the subtitle of the SUBCASE. This is done for consistency with the forward PAT3NAS translation. A job is created during the import. The name of the created job is the basename of the file being read. MSC Nastran allows load sets to be referenced in multiple places with different scale factors. This is not possible in Patran. Therefore, in some cases, multiple copies of the same load set need to be created with the only difference being the scale factor. The name of these load sets are modified to include the subcase ID to create unique names.

TABLES The following table types are supported during import of a NASTRAN input file. Note that some forms of the table commands are converted to an equivalent version supported by Patran. Card Type

Field Name

Comments

TABLED1

Field.

Imported as a frequency dependent non-spatial field. If from a timedomain fatigue analysis, imported as a time dependent non-spatial field.

TABLED2

Field.

Converted to an equivalent TABLED1 when read into Patran by NIFIMP.

Main Index

642

Patran Interface to MSC Nastran Preference Guide Data Translated from the NASTRAN Input File

Card Type

Field Name

Comments

TABLED3

Field.

Converted to an equivalent TABLED1 when read into Patran by NIFIMP.

TABLEM1

Field.

Imported as temperature dependent material properties or if from a fatigue analysis, as life dependent material properties.

TABLEM2

Field.

Converted to an equivalent TABLEM1 when read into Patran by NIFIMP.

TABLEM3

Field.

Converted to an equivalent TABLEM1 when read into Patran by NIFIMP.

TABRND1

Field.

Imported as a frequency dependent non-spatial field. If imported from a frequency domain random vibration fatigue analysis with defined RANDPS entries, some fields may be imported as complex fields.

Field.r.i TABLFTG

Field.

Imported as a time dependent non-spatial field with y-only values. x-values are 1, 2, 3, etc.

SOL 600 entries

Note:A

Additional entries specific to SOL 600 can be read into Patran. For more details see MSC Nastran Implicit Nonlinear (SOL 400/600), 15.

Fatigue Related Entries The following fatigue analysis related definitions can be read into Patran. Command

Main Index

Comments

FATIGUE FTGDEF

FATIGUE case control sets the Output Request form under Subcases form and FTGDEF defines the entities on which the fatigue analysis is performed.

DTI, UNITS FTGPARM

Defines most of the fatigue parameters set on the Fatigue Parameters form, which is found under the Solution Parameters form for Solution type, Static, Normal Modes, Frequency Response, and Modal Transient Analysis.

MATFTG TABLEM1

Defines the fatigue material properties set at constitutive models Stress-Life and/or Strain -Life.

FTGSEQ FTGEVNT FTGLOAD TABLFTG UNDAME RANDPS TABRND1

Defines the fatigue loading sequence consisting of load events and individual loads that make up each event. The table cards are imported as non-spatial fields, time dependent or frequency dependent depending on the type of fatigue analysis, time domain or frequency domain.

Chapter 5: Read Input File 643 Conflict Resolution

5.3

Conflict Resolution If an entity can not be imported into Patran because another entity already exists with that ID or name, then the conflict resolution logic is used. There are 2 different approaches taken, depending on whether the entity is identified by an ID or by a name.

Conflict Resolution for Entities Identified by IDs If a new definition conflicts with a definition already in the Patran database, you will be asked if you want the ID of the new definition offset. If you select YES, a new ID will be chosen. If you select YES FOR ALL, a new ID will be chosen for this definition, as well as for any others found to be in conflict. In this case, then all references to the ID in the original Patran database will still reference the old ID, but references to the ID from within the input file will be altered to reference the new ID. If you do not want the CID to be offset, then you will be asked if you want the new definition to overwrite the existing definition. If this is done, then all references to this ID from both the original Patran database and the input file will be referencing the same ID. The definition for that ID will be either the old or the new definition, depending on how this second question is answered.

Conflict Resolution for Entities Identified by Names The user is not asked what to do in cases where the conflicting entities are identified by names. The name for the new entity will be modified by appending an extension to the name. The new name will be “.r”. The value of n is chosen to make the new name unique. No merging of data or application regions is done. The old definition is left unchanged.

Main Index

644

Patran Interface to MSC Nastran Preference Guide Conflict Resolution

Main Index

Chapter 6: Delete Patran Interface to MSC Nastran Preference Guide

6

Main Index

Delete



Review of Delete Form

646



Deleting an MSC Nastran Job

647

646

Patran Interface to MSC Nastran Preference Guide Review of Delete Form

6.1

Review of Delete Form The Analysis form will appear when the Analysis toggle, located on the Patran main form, is chosen and the selected Action is Delete.The Delete option under Action allows the user to delete jobs that have been created for the MSC Nastran preference. .

.

Main Index

Chapter 6: Delete 647 Deleting an MSC Nastran Job

6.2

Deleting an MSC Nastran Job This format of the Analysis form appears when the Action is set to Delete. The user may delete job definitions that were created for the MSC Nastran preference with this form.

Parameter Name Analysis Code

Description Indicates the selected Analysis Code and Analysis Type, as defined in the Preferences>Analysis (p. 427) in the Patran Reference Manual.

Analysis Type

Main Index

Existing Jobs

List of already existing jobs. Select the jobs that are to be deleted.

Apply

Deletes the jobs selected in the Existing Jobs listbox.

648

Patran Interface to MSC Nastran Preference Guide Deleting an MSC Nastran Job

Main Index

Chapter 7: Files Patran Interface to MSC Nastran Preference Guide

7

Files



Main Index

Files

650

650

Patran Interface to MSC Nastran Preference Guide Files

7.1

Files The Patran MSC Nastran interface uses or creates several files.The following table outlines each file and its uses. In the file name definition, jobname will be replaced with the jobname assigned by the user. File Name

Description

*.db

This is the Patran database. During an analyze pass, model data is read from this database and, during a Read Results pass, model and/or results data is written into it. This file typically resides in the current directory.

jobname.jbr

These are small files used to pass certain information between Patran and the independent translation programs during translation. There should never be a need to directly alter these files. These files typically reside in the current directory.

jobname.bdf

This is the NASTRAN input file created by the interface. This file typically resides in the current directory.

msc_v#_sol#.alt

These are a series of MSC Nastran alters that are read during forward translation. These alters instruct MSC Nastran to write information to the OUTPUT2 file that the results translation will be looking for. The forward translator searches the Patran file path for these files, but they typically reside in the /alters directory. If these files do not meet specific needs, edit them accordingly. However, the naming conversion of msc_v# _sol#.alt must be preserved. Either place the edited file back into the /alters directory or in any directory on the Patran file path, which takes precedence over the /alters directory. If these files are not used, remove them from the Patran file path, rename them, or delete them altogether.

jobname.op2

This is the MSC Nastran OUTPUT2 file, which is read by the Read Results pass. This file typically resides in the current directory and contains both model and results data. It is created by placing a PARAM,POST,-1 in the input file.

jobname.xdb

This is the MSC Nastran XDB file or MSC.Access database, which is attached by the Read Results pass. This file typically resides in the current directory and contains results data. It is created by placing a PARAM, POST,0 in the input file.

jobname.marc.t16

SOL 600 file recommended for use in postprocessing SOL 600 analyses.

jobname.flat

This file may be generated during a Read Results pass. If the results translation cannot write data directly into the specified Patran database it will create this jobname flat file. This file typically resides in the current directory.

jobname.marc.xxx

File generated by a SOL 600 analysis. See the “MSC Nastran Implicit Nonlinear (SOL 600) User’s Guide” for a complete list.

Main Index

Chapter 7: Files 651 Files

File Name

Description

jobname.msg.xx

These message files contain any diagnostic output from the translation, either forward or reverse. This file typically resides in the current directory.

MscNastranExecute

This is a Linux script file, which is called on to submit MSC Nastran after translation is complete. This file might need customizing with site specific data, such as, host machine name and MSC Nastran executable commands. This file contains many comments and should be easy to edit. Patran searches its file path to find this file, but it typically resides in the bin/exe directory. Either use the general copy in /bin/exe, or place a local copy in a directory on the file path, which takes precedence over the /bin/exe directory.

Main Index

652

Patran Interface to MSC Nastran Preference Guide Files

Main Index

Chapter 8: Errors/Warnings Patran Interface to MSC Nastran Preference Guide

8

Errors/Warnings



Main Index

Errors/Warnings

654

654

Patran Interface to MSC Nastran Preference Guide Errors/Warnings

8.1

Errors/Warnings There are many error or warning messages that may be generated by the Patran MSC Nastran Interface. The following table outlines some of these. Message

Description

Unable to open a new message file " ". Translation messages will be written to standard output.

If the translation tries to open a message file and cannot, it will write messages to Standard Output. On most systems, the translator automatically writes messages to standard output and never tries to create a separate message file.

Unable to open the specified OUTPUT2 file "

The OUTPUT2 file was not found. Check the OUTPUT2 file specification in the translation control file.

".

The specified OUTPUT2 file " " is not in standard binary format and cannot be translated.

The OUTPUT2 file is not in standard binary format. Check the OUTPUT2 file specification in the translation control file.

Group " " does not exist in the database. Model data will not be translated.

The name of a nonexistent group was specified in the translator control file. No model data will be translated from the OUTPUT2 file.

Needed file specification missing! The full name of the job file must be specified as the first commandline argument to this program.

The translation control file must be specified as the first online argument to the translator.

Unable to open the specified database " ". Writing the OUTPUT2 information to the PCL command file " ".

If the translator cannot communicate directly to the specified database. It will write the results and/or model data to a PCL session file.

Unable to open either the specified database " PCL command file, " ". Unable to open the NASTRAN input file " Unable to open the specified database, "

", or a The naspat3 translator is unable to open any output file. Check file specification and directory protection. ".

".

The translator was unable to open a file to where the input file information will be written. The forward Patran MSC Nastran translator was unable to open the specified Patran database.

Alter file of the name " " could not be found. No The OUTPUT2 DMAP alter file, for this type of analysis, OUPUT2 alter will be written to the NASTRAN input could not be found. Correct the search path to include the file. necessary directory if you want the alter files to be written to the input file. No property regions are defined in the database. No elements or element properties can be translated.

Main Index

Elements referenced by an element property region in the Patran database will not get translated by the forward Patran MSC Nastran translator. If no element regions are defined, no elements will be translated.

Ap. A: Preference Configuration and Implementation Patran Interface to MSC Nastran Preference Guide

A

Main Index

Preference Configuration and Implementation 

Software Components in Patran MSC Nastran

656



Patran MSC Nastran Preference Components

657



Configuring the Patran MSC Nastran Execute File

660

656

Patran Interface to MSC Nastran Preference Guide Software Components in Patran MSC Nastran

1.1

Software Components in Patran MSC Nastran The Patran MSC Nastran product includes the following items: • A PCL function contained in p3patran.plb that will add MSC Nastran specific definitions to

any Patran database (not already containing such definitions) at any time. • A PCL library called mscnastran.plb and contained in the

directory. This library is used by the analysis forms to produce forms for analysis code specific translation parameter, solution parameter, etc. • A script file called MscNastranExecute, contained in the /bin/exe

directory. This script controls the operation of the interface and the submission of MSC Nastran analyses. This script can be run independent of Patran but typically run from within Patran, transparent to the user. • Several MSC Nastran alter files are included. These files are used when creating the NASTRAN

input file. They ask MSC Nastran to produce the results file required by the NASPAT3 results translator. These files can be found in the /alter directory. They must follow the naming convention msc_v_sol.alt. For example, msc_v67_sol3.alt. If these files do not meet the user’s needs, they should be modified. Alter files specific to LMS CADA-X are also included. These files are identical to the standard alter files except for an additional “.lms” extension, e.g., msc_v67_sol3.alt.lms. These files are usually needed only when the user requires support for older solution sequences. • This Patran MSC Nastran Interface Manual is included as part of the product. An on-line version

is also provided to allow the direct access to this information from within Patran.

Main Index

Ap. A: Preference Configuration and Implementation 657 Patran MSC Nastran Preference Components

1.2

Patran MSC Nastran Preference Components The diagrams shown below indicate how the functions, scripts, programs, and files that constitute the Patran MSC Nastran interface affect the Patran environment. Site customization, in some cases, is indicated. Figure A-1 shows the process of running an analysis. The mscnastran.plb library defines the Translation Parameter, Solution Type, Solution Parameter, and Output Request forms called by the Analysis form. When the Apply button is pushed on the Analyze form, the interface process is initiated. The interface reads data from the database and creates the NASTRAN input file. Status messages from the interface are recorded in the Patran session file. A series of MSC Nastran alter files is provided. They may be used during the creation of the input file depending upon the selected solution type and solution parameters. These alter files are mostly used in support of older solution sequences. If the interface successfully produces a NASTRAN input file, and the user requests it, the MscNastranExecute script will then start MSC Nastran.

Patran

p3patran.plb

Analysis mscnastran.plb

Analyze

MscNastranExecute Patran Database Alter Library

jobname.bdf

Figure A-1

MSC Nastran

Forward Translation

Figure A-2 shows the process of reading information from an MSC Nastran OUTPUT2 file. When the

Apply button is selected on the Read Output2 form, a .jbr file is created and the results translation is started. The results interface process reads the data from the MSC Nastran OUTPUT2 file

Main Index

658

Patran Interface to MSC Nastran Preference Guide Patran MSC Nastran Preference Components

and stores the results in the Patran database. Status messages from the interface are recorded in the Patran session file.

p3patran.plb Patran Analysis

mscnastran.plb

Read Output2

jobname.jbr Patran database

MSC Nastran

Figure A-2

jobname.OP2

OUTPUT2 File Translation

Figure A-3 shows the process of translating information from a NASTRAN input file into a Patran database. The behavior of the main Analysis/Read Input File form and the subordinate file select form is

Main Index

Ap. A: Preference Configuration and Implementation 659 Patran MSC Nastran Preference Components

dictated by the mscnastran.plb PCL library. The Apply button on the main form activates the input file reader program, which reads the specified NASTRAN input file.

Patran p3patran.plb Analysis

Read Input File

mscnastran.plb

MSC Nastran Input

Patran database

File Reader

NASTRAN Input File

input_file_name.error.* Figure A-3

Main Index

NASTRAN Input File Translation

660

Patran Interface to MSC Nastran Preference Guide Configuring the Patran MSC Nastran Execute File

1.3

Configuring the Patran MSC Nastran Execute File During the installation of the Patran MSC Nastran analysis preference, the mscsetup utility creates a default site_setup file in the installation directory. This file sets environment variables relating to Patran. To custom configure this site_setup file consult Environment Variables (p. 42) in the Patran Installation and Operations Guide.

Main Index

MSC.Fatigue Quick Start Guide

Index Patran Interface to MSC Nastran Preference Guide

Numerics I n d e x

P atr an Int erf ac e to M

1D- Grounded Bush/Bush (CBUSH2D/ PBUSH2D), 150 3D - Body Pair- Geometric, 227 3D - Body Pair- Physical, 229 3rd Order Invariant, 77

A

ACFPMRESULT, 482 ACPOWER, 482 ADAPT, 120, 132, 161, 173, 184, 190, 213, 220 Adaptive Meshing, 476 adaptive meshing, 573 alternate reduction, 314 ALTERS, 656 Alters, 298 ALTRED, 314 analysis coordinate frames, 29 analysis form, 293 analysis job definition, 296 analysis job submittal, 296 analysis preferences, 6 analyze, 292 Arruda-Boyce model, 79 augmentation, 358

B

BCBDPRP, 15 BCBMRAD, 118 BCBODY, 15 BCBODY1, 15 BCBOX, 15 BCHANGE, 15 BCMATL, 15 BCMOVE, 15 BCNURB2, 15 BCNURBS, 15 BCONECT, 15 BCONPRG, 15

Main Index

BCONPRP, 15 BCONTACT, 15 BCPARA, 15 BCPATCH, 15 BCPROP, 15 BCRGSRF, 15 BCRIGID, 15 BCTABL1, 15 BCTABLE, 15 BCTRIM, 15 BEADVAR, 544, 548 BEGIN AFPM, 179, 482 BEGIN BULK SUPER, 300, 409 Body Pair, 107 BSURF, 15 buckling, 326 bulk data, 9 bulk data file, 620

C

CACINF3, 209 CACINF4, 209 case control, 8 CBAR, 114, 122, 123 CBARAO, 114, 122, 123 CBEAM, 120, 128, 130, 132, 133, 135, 136, 137 CBEND, 124, 126 CBUSH, 113, 148 CDAMP1, 112, 142 CDAMP1D, 142 CELAS1, 111 CELAS1D, 141 CFAST, 153 CGAP, 144 CGI, 273 CHEXA, 217, 219, 220, 222, 223, 225 CID Distributed Load, 243 CIFCDX, 95

662 Patran Interface to MSC Nastran Preference Guide

CIFHEX, 95, 226 CIFPENT, 95, 226 CIFQDX, 208 CIFQUAD, 95, 195, 199 CMASS1, 109, 146 complex Eigenvalue, 332 CONM1, 108 CONM2, 110 contact, 243 penetration, 351 contact bodies deformable surfaces defining in MSC.Patran, 262, 263 rigid surface defining in MSC.Patran, 264 slideline defining in MSC.Patran, 261 coordinate frames, 28, 582 analysis, 29 reference, 29 coordinates, 299 COUPMASS, 320 CPENTA, 217, 220, 222 CQUAD, 192 CQUAD4, 156, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, 180, 184, 186, 188, 190, 193, 196, 198, 210, 212, 213 CQUAD8, 156, 165, 169, 180, 186, 188, 192, 193, 198, 210 CQUADR, 182, 189 CQUADX, 200, 202, 203, 204, 205, 206 crack (VCCT), 243, 271 CREEP, 88 Creep, 65 CROD, 138, 139 CSHEAR, 215 CTETRA, 217, 219, 220, 222, 224 CTRIA3, 156, 161, 163, 165, 169, 173, 179, 180, 184, 186, 190, 192, 194, 210, 213 CTRIA6, 156, 165, 169, 180, 186, 192, 196, 210 CTRIAR, 159, 167, 171, 182, 189, 212 CTRIAX, 200, 204, 206, 207 CTRIAX6, 200 CTUBE, 140 CVISC, 143 CWELD, 152

Main Index

CYAX, 50 cyclic symmetry, 36, 50, 314, 326, 338 CYJOIN, 50 CYSYM, 50

D

DCONSTR, 542 degrees-of-freedom, 38 DEQATN, 541 DESGLB, 542 DESOBJ, 541 DESSUB, 542 DISPLACEMENT, 483 displacements, 248 distributed load, 243 DOPTPRM, 537, 539, 543, 544 DPHASE, 248, 251 DRESP1, 541 DRESP2, 541 DRSPAN, 541 DTI,UNITS, 371, 375 dynamic reduction, 324 DYNRED, 324

E

EIGB, 329 EIGC, 335 Eigenvalue extraction, 320, 327 buckling, 329 complex, 335 real, 322 EIGR, 322 EIGRL, 329 element properties, 101

INDEX 663

elements, 582 2d solid, 186, 189 acoustic field point mesh, 179 axisymmetric solid, 200, 206 coupled point mass, 108 curved general section, 124 curved pipe, 126 gap, 144 general beam, 133 general section beam, 114 general section rod, 138, 139 grounded scalar damper, 112 grounded scalar mass, 109 grounded scalar spring, 111 infinite exterior acoustic, 209 linear cubic closed section beam, 122 linear shear beam, 123 lumped area beam, 128 lumped point mass, 110 p-formulation, 20, 220 P-Formulation bending panel, 184 P-Formulation Equivalent Section plate, 173 P-Formulation general section beam, 120 P-Formulation homogeneous plate, 161 P-Formulation Membrane, 213 P-Formulation Plane Strain Solid, 190 pipe section, 140 plane stress solid, 196 plotel, 147 revised bending panel, 182 revised equivalent section plate, 171 revised homogeneous plate, 159 revised laminate plate, 167 revised membrane, 212 revised plane strain solid, 189 scalar damping, 142 scalar mass, 146 scalar spring, 141 shear panel, 215 solid, 217 standard bending panel, 180 standard equivalent section plate, 169 standard homogeneous plate, 156 standard laminate plate, 165

Main Index

standard membrane, 210 standard plane strain solid, 186 tapered beam, 130 viscous damper, 143 ELSDCON, 483 Environment Variables ACommand20xx, 565 DRA_NAST_NOVEDRCHK, 565 MSP_NASTRAN_CMD20xx, 565 errors, 654 ESE, 483 executive control, 8

F

failure criteria, 84 FATIGUE, 483, 490 FEEDGE, 21 FEFACE, 23 files, 650 finite elements, 29, 30 FMS, 8 Foam model, 77 follower forces, 317 FORCE, 251, 252, 483 force, 242, 251 frequency response, 338 FTGDEF, 490 FTGEVNT, 519 FTGLOAD, 519 FTGPARM, 370 FTGSEQ, 519

G

GC, 274 Gent model, 79, 96, 97, 98 GEOM1, 582 GEOM2, 582 Geometric, 107 GMBC, 23 GMNURB, 15 GPFORCE, 483 GRAV, 257 GRDPNT, 321

664 Patran Interface to MSC Nastran Preference Guide

H

H5NORDOF, 406 HDF5, 406 Hypoelastic, 65

I

IGROW, 273 INCM, 273 inertia relief, 314 inertial load, 257 initial conditions, 242, 257 initial load, 242 initial velocity, 242 input file, 620 INREL, 314 INTENSITY, 482 IPSTRAIN, 15 ISTRESS, 15 iteration parameters, 451 iterations static nonlinear, 416 ITYPE, 273

J

Jamus-Green-Simpson model, 76, 77

K

keywords POST, 361 REAUTO, 361, 535 VCCT, 271

L

large displacements, 317 LGDISP, 318 linear surf-vol, 34 linear transient, 341 load cases, 275 loads and boundary conditions, 240

M

MARCIN, 15 MARCOUT, 15 Mass properties, non-structural (MSC.Nastran),

Main Index

509 MAT1, 73, 84 MAT10, 209 MAT2, 84 MAT3, 73 MAT8, 73, 84 MATEP, 16, 17, 81 materials, 58 2D anisotropic, 68, 72, 74 2D orthotropic, 66, 72 3D anisotropic, 68, 72, 74 3D orthotropic, 67, 72 Cohesive, 68 composite, 68, 99 Fluid, 68 isotropic, 62, 69, 73, 75 MATF, 16, 17, 85 MATFTG, 92 MATG, 16 MATHE, 16, 17, 76 MATORT, 16, 17, 73 MATS1, 75, 76, 81 MATTEP, 16, 17 MATTF, 85 MATTG, 16 MATTHE, 16, 17 MATTi, 73 MATTORT, 16 MATTVE, 16, 91 MATVE, 16, 91 MATVP, 16, 88 MCOHE, 95 MDLPRM, 406 METHOD, 273 model data, 567 MODTRAK, 541 MOMENT, 251 Mooney-Rivlin model, 76, 77 MPC, 34, 38, 51 MSC.Nastran enhancements Non-structural mass properties, 509 MSC.Nastran version, 299, 300, 568, 569, 571, 572 MSTACK, 225 multi-point constraints, 32

INDEX 665

N

Neo-Hookean, 77 NLAUTO, 16 NLDAMP, 16 NLLOAD, 483 NLPARM, 416 NLSTRAT, 16 nodes, 29, 299, 582 nonlinear elastic, 75 nonlinear statics, 315 nonlinear transient, 344 Non-Structural mass properties (MSC.Nastran), 509 normal nodes, 319 NSM and NSML forms (MSC.Nastran), 509 NTHICK, 16 numbering options, 301

O

OEF1, 574, 575 OESNL1, 575 Ogden model, 77 OLOAD, 482 ONRGY1, 577 OPG1, 577 OPHIG, 578 OPNL1, 578 optimize, 537 optimization parameters, 537, 539 subcase create, 538, 540 subcase select optimize, 538, 540 topography optimization, 539 topology optimization, 539 topometry optimization, 539 OSTR1, 574, 575 OUGV1, 577 output requests, 478 OUTPUT2, 298 OUTRCV, 25

P

PACINF, 209 PARAM, SNORM, 314, 320, 333, 339, 342, 381 PARAMARC, 16 PBAR, 114, 122, 123

Main Index

PBARL, 114, 122, 123 PBARN1, 114, 122, 123 PBCOMP, 128 PBEAM, 120, 130, 132, 133, 135, 136, 137 PBEAML, 120, 130, 132, 133, 135, 136, 137 PBEMN1, 135, 136, 137 PBEND, 124, 126 PBUSH, 113, 148 PBUSHT, 147, 148 PCOHE, 95, 195, 199, 208, 226 PCOMP, 84, 99, 165, 167, 225 PCOMPG, 165, 167 PCOMPLS, 225 PDAMP, 112, 142 PELAS, 111, 141 penetration, 351 PFAST, 153 PFTG, 158 PGAP, 144 Physical, 107 PLCOMP, 193, 205 PLOAD4, 252 PLOADX1, 252 PLPLANE, 188, 192, 194, 196, 198, 200, 202, 203, 204, 206, 207 PLSOLID, 222 PMASS, 109, 146 POINT, 21 Postprocessing, 476 preferences, 6 pressure, 242, 252 PROD, 138 properties, 101 PSHEAR, 215 PSHEARN, 215 PSHELL, 156, 159, 161, 169, 171, 180, 182, 186, 189, 190, 210, 212, 213 PSHLN1, 163, 175, 177, 210 PSHLN2, 188, 194, 196, 198, 200, 202, 203, 206, 207 PSLDN1, 217, 219, 223, 224 PSOLID, 217, 219, 220, 223, 224 PTUBE, 140 PVAL, 120, 132, 161, 173, 184, 190, 213, 220 PVISC, 143

666 Patran Interface to MSC Nastran Preference Guide

PWELD, 152

R

RANDPS, 519 RBAR, 34, 40 rbar1, 52 RBE1, 34, 42 RBE2, 35, 40, 43 RBE3, 35, 44 read input file, 620 reference coordinate frames, 29 RESTART, 16 restart file, 362, 536 results, 562 element, 500 nodal, 498 supported entities, 574, 588 types, 583 results output format, 405 RFORCE, 257 rjoint, 54 RLOAD1, 248 RROD, 35, 46 RSPLINE, 35, 47 RSSCON, 34 RTRPLT, 36, 48 rtrplt1, 53

S

SESET, 409 SET1, 490 SET4, 490 SETREE, 409 sliding surface, 36, 51 solution parameters, 312 SOL 109, 341 SOL 112, 341 SOL 27, 341 SOL 31, 341

Main Index

solution sequences SOL 1, 306, 314 SOL 101, 306, 314 SOL 103, 306 SOL 105, 306 SOL 106, 306, 315 SOL 107, 332 SOL 108, 306, 338 SOL 109, 306 SOL 110, 306, 332 SOL 111, 306, 338 SOL 112, 306 SOL 114, 306, 314 SOL 115, 306 SOL 118, 306, 338, 339 SOL 129, 306, 344 SOL 147, 306 SOL 26, 306, 338 SOL 27, 306 SOL 28, 306, 332 SOL 29, 306, 332 SOL 3, 306 SOL 30, 306, 338 SOL 37, 306 SOL 47, 306, 314 SOL 48, 306 SOL 5, 306 SOL 600, 306, 346, 381, 383 SOL 66, 306, 315 SOL 77, 306 SOL 99, 306, 344 solution types, 305 SPC1, 248 SPCD, 248 SPCFORCES, 483 SPCR, 249 SPOINT, 133 static data, 244 STRAIN, 483 Strain Life, 66 STRESS, 482, 483 Stress Life, 66 structural damping, 334, 343, 345 superelements, 300, 409 supported entities, 8

INDEX 667

T

t16 file, 583, 615 TABCGI, 274 TABGC, 274 TABLEDi, 248, 251 TABLEMi, 73 TABLES1, 76 TABLFTG, 519 TABRND1, 519 TEMP, 254 temperature, 242, 254 TEMPP1, 254 TEMPRB, 254 TIC, 257 TIM2PSD, 524 time dependent, 247 tolerances, 298, 567, 569, 571, 572 TOMVAR, 543, 547 TOPVAR, 543, 545, 546 Total Load, 270 translation parameters, 298, 567, 569 TSTEPNL, 419, 470

U

UDNAME, 519 Use Contact Table, 351, 415, 423, 436, 438, 441, 443 User Defined, 66 User Defined Services, 367 User Sub. (UCOHESIVE), 68 User Sub. UFAIL, 65 User Sub.(CRPLAW), 65

V

VECTOR, 483 Viscoelastic, 66 VU mesh, 25

W

warnings, 654 WTMASS, 321

Main Index

668 Patran Interface to MSC Nastran Preference Guide

Main Index