MSC Patran-Nastran Preference Guide Volume 3(2018): implicit nonlinear analysis [2018 ed.]

Table of contents :
Overview......Page 9
Setting the Analysis Code and Type......Page 10
Load Steps......Page 12
Problem Statement......Page 14
Model Description......Page 15
Creating the Model in Patran......Page 18
Highlights of the MSC Nastran Analysis......Page 33
More Advanced Topics......Page 40
Building A Model......Page 49
Nodes and Elements......Page 50
Nodes......Page 51
Multi-point Constraints......Page 52
Material Constitutive Models......Page 58
Material Input Properties......Page 62
Element Properties......Page 89
Element Properties Form......Page 98
0D Element Properties......Page 99
1D Element Properties......Page 109
2D Element Properties......Page 144
3D Element Properties......Page 196
Loads and Boundary Conditions......Page 215
Loads & Boundary Conditions Form......Page 216
Loads and Boundary Condition Objects......Page 226
Load Cases......Page 251
Contact Bodies......Page 252
Deformable Body......Page 254
Rigid Body......Page 263
Body Pair......Page 270
Running an Analysis......Page 283
Review of the Analysis Form......Page 284
Analysis Create......Page 285
Access Results......Page 288
Read Input File......Page 290
Delete Analysis Job......Page 292
Monitor......Page 293
Abort Job......Page 296
Run Demo......Page 298
Translation Parameters......Page 299
Precision Control......Page 303
Numbering Options......Page 304
Solution Parameters......Page 306
Contact Control Parameters......Page 310
Direct Text Input......Page 320
Load Steps......Page 322
Create Load Step......Page 324
Edit Load Steps......Page 327
Load Step Parameters......Page 328
Static Parameters......Page 330
Normal Modes Parameters......Page 332
Buckling Parameters......Page 335
Transient Dynamic Parameters......Page 338
Steady State Heat Parameters......Page 340
Transient Heat Parameters......Page 341
Solvers/Options......Page 342
Load Increment Parameters......Page 345
Iteration Parameters......Page 350
Contact Table......Page 353
Brake Squeal Parameters......Page 364
Real Eigenvalue Extraction......Page 366
Define Time Step......Page 368
Define Damping......Page 369
Output Requests......Page 370
Basic Output Requests......Page 372
Advanced Output Requests......Page 374
Output Request Descriptions......Page 380
Edit Output Requests......Page 383
nas_implnl_user_add_out_req......Page 386
nas_implnl_user_del_out_req......Page 387
Load Step Select......Page 391
Supported Entities......Page 397
MSC Nastran Results Access......Page 398
Results File Formats......Page 400
Results Access Settings......Page 401
Results Translation Parameters......Page 402
Supported Result Quantities......Page 403
MSC Nastran Input File Import......Page 409
Entity Selection Form......Page 412
Define Offsets Form......Page 414
Summary Data Form......Page 417
Data Translation Notes......Page 418
Supported Model Entities......Page 422
Files Created......Page 436

Citation preview



Patran 2018

Interface To MSC Nastran Preference Guide Volume 3: Implicit Nonlinear

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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 2018 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:V2018:Z:INT:INON:DC-USR-VOL-3

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Main Index

Contents Patran MSC Nastran Preference Guide-Implicit Nonlinear

Contents

1

Overview Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Setting the Analysis Code and Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Modeling Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Load Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A Nonlinear Example Problem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Problem Statement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Model Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Creating the Model in Patran . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Highlights of the MSC Nastran Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . More Advanced Topics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2

Main Index

2 2 4 4 6 6 7 10 25 32

Building A Model Coordinate Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

42

Nodes and Elements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nodes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Multi-point Constraints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

42 43 44 44

Materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Constitutive Models. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Material Input Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Element Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Element Properties Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0D Element Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1D Element Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2D Element Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3D Element Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Loads and Boundary Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Loads & Boundary Conditions Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Loads and Boundary Condition Objects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

50 50 54 81 90 91 101 136 188 207 208 218

vi Patran MSC Nastran Preference Guide-Implicit Nonlinear

3

Main Index

Load Cases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

243

Contact Bodies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Deformable Body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rigid Body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Body Pair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

244 246 255 262

Running an Analysis Review of the Analysis Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Analysis Create . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Access Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Read Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Delete Analysis Job . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Abort Job . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Run Demo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Translation Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Precision Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Numbering Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bulk Data Include File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Solution Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Contact Control Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Direct Text Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

276 277 280 282 284 285 288 290 291 295 296 298 298 302 312

Load Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Create Load Step . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Delete Load Step . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Edit Load Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Load Step Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Static Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Normal Modes Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Buckling Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Transient Dynamic Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steady State Heat Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Transient Heat Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Solvers/Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Load Increment Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Iteration Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Contact Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Brake Squeal Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Real Eigenvalue Extraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Define Time Step . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Define Damping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Output Requests. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

314 316 319 319 320 322 324 327 330 332 333 334 337 342 345 356 358 360 361 362

Contents vii

Basic Output Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Advanced Output Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Output Request Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Edit Output Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Customizing Default Output Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Load Step Select. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4

Main Index

364 366 372 375 378 383

Supported Entities MSC Nastran Results Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Results File Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Results Access Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Results Translation Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Supported Result Quantities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MSC Nastran Input File Import. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Entity Selection Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Define Offsets Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Summary Data Form. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Data Translation Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Supported Model Entities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

390 392 393 394 395 401 404 406 409 410 414

Files Created . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

428

viii Patran MSC Nastran Preference Guide-Implicit Nonlinear

Main Index

Chapter 1: Overview MSC Nastran Implicit Nonlinear (SOL 600) User’s GuidePatran MSC Nastran Preference Guide - Implicit Nonlinear

1

Main Index

Overview



Overview



A Nonlinear Example Problem

2 6

2

Patran MSC Nastran Preference Guide - Implicit Nonlinear Overview

Overview The Implicit Nonlinear analysis type in the Patran MSC Nastran preference provides a direct interface to MSC Nastran’s SOL 400 implicit nonlinear capabilities. There are many aspects to building a finite element analysis model. Many of 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. It is assumed that at this point a finite element model (nodes and elements) exist. Thus this guide only details what is necessary to prepare that model for a proper implicit nonlinear analysis via SOL 400. Building a model for implicit nonlinear analysis is similar to that of structural and thermal analysis. This Guide gives specific information and details regarding creation of multi-point constraints (MPCs), materials, element properties, loads and boundary conditions, contact definitions, Load Step creation, and analysis setup tailored to an MSC Nastran SOL 400 analysis.

Setting the Analysis Code and Type To start using the Implicit Nonlinear analysis preference, it is necessary to set the Analysis Code and Analysis Type. When opening a new database, you are prompted for this information right away in a from that appear whenever a new database is opened. Otherwise the preference can be set under the Menu || Preference || Analysis option. Either way, set the Analysis Code accordingly (e.g., MSC Nastran) and Analysis Type (e.g., Implicit Nonlinear).

Setting the Analysis preference options defines what is presented to you in several areas of Patran during the subsequent modeling steps. These areas include applicable MPCs, materials, element properties, loads and boundary conditions, and the analysis setup forms.

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Chapter 1: Overview Overview

Changing Preferences It is possible and allowable to change back and forth between Analysis Preferences either by changing the Analysis Code completely or by just changing the Analysis Type within a particular code. Please note however, that doing so can result in data loss. For example there are many material and element properties that are not compatible between analysis codes or types. When a property is not compatible, and the Preference is changed, that property becomes unavailable in the new Preference. Changing the Preference back, then makes that property visible again. The most common operation is likely the changing of the Analysis Type from Structural to Implicit Nonlinear. When this operation is performed and incompatible properties are detected, the user is prompted to convert the properties. Answering Yes converts the properties so that they are compatible and visible in the Implicit Nonlinear preference. Answering No leaves the properties as-is and these properties, while still defined in the database, are not available or usable in the Implicit Nonlinear preference and you will need to redefine them if necessary. Answering No allows you to then move back to the Structural preference without modification so that the properties are preserved. Once the properties are converted however, moving back to the Structural preference may result in the converted properties being inaccessible. In some cases two-way conversion is possible, but in others it is not.

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Overview

Modeling Steps Note that it is assumed that a finite element model is already defined. For details on this process, please see: • Introduction to Geometry Modeling (Ch. 1) in the Geometry Modeling - Reference Manual Part 2) • Introduction to Finite Element Modeling (Ch. 1) in the Reference Manual - Part III

A typical scenario consists of these generic steps when preparing an implicit nonlinear analysis for SOL 400. 1. Define MPCs, if necessary (see Multi-point Constraints, 44) 2. Define material properties (see Materials, 50) 3. Associate materials and element properties to the finite elements (see Element Properties, 81) 4. Apply loads and boundary conditions (see Loads and Boundary Conditions, 207) 5. Create contact and contact pair definitions, if necessary (see Contact Bodies, 244) 6. Set up various Load Steps as needed (see Load Steps, 314) 7. Define appropriate analysis parameters (see Review of the Analysis Form, 276) 8. Associate Load Steps to your analysis (see Load Step Select, 383) 9. Create the MSC Nastran input file and submit the analysis (see Review of the Analysis Form, 276)

Load Steps SOL 400 implicit nonlinear analysis is performed as one or more chained analyses referred to as Load Steps. This differs from the normal concept of a Subcase in MSC Nastran. A subcase refers to a completely separate and contained analysis. A SOL 400 subcase contains any number of chained Load Steps. The presence of more than one subcase indicates separate analyses are to be performed, which are unrelated to each other from the standpoint that they require completely new formulations of the stiffness matrices and load vectors. A subsequent Load Step within a subcase uses the previous state of the stiffness matrices/load vectors to continue the analysis on to another state. As an example here is a Case Control set up with two SUBCASEs (the solution of which are independent of one another). Each subcase contains various Load Steps. The solution of any STEP is a continuation of the solution of the previous STEP. For more detail see Load Step Select, 383. SUBCASE 1 STEP 1 ANALYSIS = LOAD = 1 STEP 2 ANALYSIS = LOAD = 2 SUBCASE 2 STEP 10 ANALYSIS = LOAD = 10 STEP 20 ANALYSIS = LOAD = 20

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NLSTAT NLSTAT

HSTAT NLSTAT

Chapter 1: Overview Overview

The following Load Step analysis types are supported: Type

Description

Static

Nonlinear static analysis requires the solution of nonlinear equilibrium equations, for which SOL 400 uses Newton’s method. Many problems involve history dependent response. Thus, the solution is usually obtained as a series of increments, with iterations within each increment to obtain equilibrium. For most cases, the automatic increment/iteration method provided by SOL 400 is preferred, although direct user control is also provided for those cases where users want manual control. Static steps can also be defined as linear for perturbation analysis.

Normal Modes

This solution type uses eigenvalue techniques to extract the natural frequencies of the current system. The stiffness determined at the end of the previous step is used as the basis for the extraction, so that vibrations of the initial or a pre-loaded structure can be investigated.

Buckling

As with normal modes, buckling modes of the current system are determined based on the incremental stiffness matrices, so that critical loads due to buckling of the initial and/or pre-loaded structure can be investigated.

Transient Dynamic Transient response analysis is the most general method for computing forced dynamic response. The purpose of a transient response analysis is to compute the behavior of a structure subjected to time-varying excitation. The transient excitation is explicitly defined in the time domain. All of the forces applied to the structure are known at each instant in time. Forces can be in the form of applied forces and/or enforced motions. The important results obtained from a transient analysis are typically displacements, velocities, and accelerations of grid points, and forces and stresses in elements and at contact interfaces. As with Statics, Transient Dynamic steps can also be defined as linear for perturbation analysis.

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Steady State Heat Transfer

This solution type determines the temperature field in a steady state heat transfer problem due to various convection, conduction, and other heat sources and boundary conditions. The resulting temperatures are typically used as loads for a subsequent structural load step in a chained or fully coupled thermal/structural analysis.

Transient Heat Transfer

This solution type determines the time dependent temperature field in a transient heat transfer problem due to various convection, conduction, and other heat sources and boundary conditions. The resulting temperatures are typically used as loads for a subsequent structural load step in a chained or fully coupled thermal/structural analysis.

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

A Nonlinear Example Problem In this section, a sample nonlinear problem called pipe crush is analyzed to show some standard features of MSC Nastran SOL 400, including contact and nonlinear materials. The problem is an elastic-plastic collapse of a cylindrical pipe under external rigid body loading.

Problem Statement A model of a cylindrical pipe is subjected to crushing as rigid bodies above and below the pipe move inward toward each other. This exercise illustrates several SOL 400 capabilities including large displacement, contact between rigid and deformable bodies, and large strain plasticity modeled with an elastic-perfectly plastic model.

Figure 1-1 The Pipe Crush Structure and Loading Steel pipes of this size are often used in land-based and offshore oil and gas industries. Individual pipe sections are assembled with threaded connectors to form large pipeline distribution systems. The pipe sections and their connections must withstand installation and operational loads. The effects of these loads can be buckling, torque, bending, axial separation, external pressure, and internal pressure. In addition to environmental loads, surrounding structures undergoing displacement can introduce contact conditions. Forces from these external structures can also lead to intolerable failure scenarios. Pipe design typically looks at all foreseeable failure scenarios and then a design is measured against the failure mode that is most critical to structural integrity. In most cases, the failure mode is bending combined with axial forces while under external pressure (if submerged) and internal pressure (fluid flow). However, in this case we examine failure due to external loading from adjacent structures. In this problem, the pipe section is subjected to offset lateral loading from external structures on the top and bottom. The problem attempts to quantify whether the movement of these external structures cause the plastic collapse of the pipe. Initial contact with the external structures is expected to cause elastic deformation of the steel pipe. Additional incremental movement potentially subjects the structure to stresses beyond the proportional limit of the material. The yield stress defines the onset of plastic strains that may initiate the collapse of the structure walls.

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The resulting deformation data can establish the conditions for catastrophic collapse of the pipe section and define allowable limits to contact of external structures.

Model Description The model is a 3-D representation of the deformable pipe structure and two semi-circular cylindrical sections of rigid pipes sections. The model uses 3-D shell elements to model the pipe, and surfaces above and below to model the rigid pipes.

Geometry and Contact Regions This problem examines a section of steel pipe eight (8) inches in diameter and 24 inches long with a wall thickness of 0.4 inches. The pipe surface is void of attachments, holes, bends, or other discontinuities and the internal volume is empty space. Two external, rigid pipe structures are oriented in a perpendicular direction and lie directly on the top and underneath the primary pipe. The bottom pipe measures six(6) inches in diameter with a length of 10 inches and the top pipe measures eight (8) inches in diameter also with a length of 10 inches. The external pipe structures that lie directly on top and bottom surface of the primary pipe impose no initial displacement or force, and no conditions are assumed to exist that might cause friction or slippage at the interface. These external structures move laterally into the pipe section creating a “sandwiching” effect. The pipe movement causes deformations on both the upper and lower side of the pipe.

Finite Element and Contact Model Actual sections of oil and gas pipes can extend past 30 feet. Lengths beyond the 24-inch section modeled in this problem are assumed be irrelevant in the local collapse of the pipe wall. Each end of the pipe model is assigned boundary conditions to represent the extension of the pipe in both directions. In addition, the pipe wall is sufficiently thin so that it is modeled with thick shell elements in this problem. The finite element mesh for the primary pipe structure contains 18 elements around the circumference and 18 elements along the length for a total of 324 elements. MSC Nastran CQUAD4 elements are selected along with the PSHELL entry that accounts for standard membrane, bending and transverse shear behavior. All shell elements are assigned a thickness of 0.4 inches, designated with five(5) layers, and the material is some grade of steel. In defining the contact model, the primary pipe section is modeled as a deformable body and the two external pipe structures are modeled as rigid bodies. Elements comprising the deformable pipe structure are flagged so that contact by a rigid body creates forces that are used to calculate the deformation of the pipe. The rigid body structures do not deform and their movement is described with the BCBODY1 option. The geometry profile of the rigid surface is defined using 3-D NURB surfaces that describe the true surface geometry and most accurately represent the curved surfaces.

Material The entire pipe section is made of steel and modeled as an elastic-plastic material using the MAT1 and MATEP entries for large displacement analysis. The linear elastic behavior model is effective up to a yield stress of 36,000 psi. In this range, imposed stresses induce linear proportional strains. The stress- strain relationship

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is defined using an elastic modulus of 3.0E+6 and a Poisons ratio of 0.3. Beyond the yield point perfect plasticity causes complete yielding of the material upon any incremental stress.

Solution Procedure and Controls A static analysis is performed to determine the pipe deformations that result from contacting rigid bodies. The rigid body movement and material stiffness specified for this problem require that large displacement effects be included (PARAM LGDISP). Rigid body movement is spread over multiple load increments to allow for the history-dependent nature of the material response. Thus the equilibrium state and material state at the end of the first increment constitutes the beginning state for the second increment. The automatic load increment option (NLSTEP) is used to control the magnitude of the load increment. The initial time increment is set at.01 sec. The total load is 2 inches of imposed rigid body lateral movement on the top and bottom of the pipe occurring over 1 sec. Within each increment, an iterative process obtains an equilibrium state. Iterations are based on the Full Newton-Raphson method with a desired number of iterations per increment being three (3), and a maximum set at 2,500. Convergence for each increment is defined based on relative residual forces of less than 0.1. Output requests are made for four stress-strain and contact components using standard MSC Nastran case control entries. Total strain tensor, stress tensor, plastic strain tensor, and Cauchy stress tensor, and contact results are requested to be included in the MASTER file.

Loads and Boundary Conditions Because only a small section of the pipe is modeled, the ends of the pipe are constrained in all translations. This boundary condition effectively represents the pipe extending a substantial distance in both directions in which case no translation movement would occur at this section's boundary. To model the contact, the top and bottom rigid surfaces are given velocity vectors of minus two (-2) in/sec., and plus two (+2) in/sec., respectively, in the y-direction (lateral). This causes the upper structure to be pushed onto the top of the pipe section and the lower structure to be pushed up into the bottom of the pipe section at a rate of two (2) in/sec. for a total time of one (1) second. It should be noted here that in nonlinear static analysis, no dynamic or inertial effects are considered. References to time are actually describing load fractions such that in nonlinear static analysis “time = 1.0" is actually referring to 100% of the first (1st) load step being applied. For multi-step analyses where the beginning state of the current load step is the final state of the previous load step, “time” is then referring to the loading state relative to the multi-step analysis. In other words, for a three step analysis time = 2.0 is referring to the loading state applied at the end of the second load step.

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Figure 1-2 Loads and Boundary Conditions

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

Creating the Model in Patran The pipe crush example is designed to be constructed and setup using Patran and analyzed using MSC Nastran SOL 400. The geometry is constructed and then property/load assignments are made in Patran. The input file (.bdf ) is exported and then run through MSC Nastran. Results are accessed in text form or from inside Patran and processed for viewing the pipe deformations and stresses. 

This and other problems may be run from within Patran from the Analysis application. Set the Action to Run Demo and select the Pipe Crush Simulation option from the Select Demo - Implicit Nonlinear menu.

If you wish to set up the problem manually, brief step-by-step instructions are given here. Step 1: Create a New Database 1. From the File pull down menu, select New. 2. Type crush400 as the File name and press OK. 3. When the New Model Preference form appears, set the Analysis Code to MSC Nastran and the Analysis Type to Implicit Nonlinear and press OK. Step 2: Create the Defining Geometry You may wish to set the labels ON and the point size larger.

1. Open the Geometry application/tab 2. Set the Action/Object/Method to Create/Point/XYZ 3. Enter [-3,-7.1,4.5] as Point Coordinates List and press Apply 4. Enter [0,-7.1,4.5] as Point Coordinates List and press Apply

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5. Set the Action/Object/Method to Create/Curve/Revolve 6. Enter {Point 1[X1 Y1 5.0]} as Axis, 180 as Total Angle, and Point 2 as Point List and press Apply (with Auto Execute ON, you don’t need to press Apply if you select Point 2 from the graphics screen)

7. Set the Action/Object/Method back to Create/Point/XYZ 8. Enter [2,8.1,4.5] as Point Coordinates List and press Apply 9. Enter [6,8.1,4.5] as Point Coordinates List and press Apply

10. Set the Action/Object/Method back to Create/Curve/Revolve 11. Enter {Point 4[X4 Y4 5.0]} as Axis, -180 as Total Angle, and Point 5as Point List and press Apply (with Auto Execute ON, you don’t need to press Apply if you select Point 5from the graphics screen)

12. Set the Action/Object/Method to Create/Point/XYZ 13. Enter [-12,0,0] as Point Coordinates List and press Apply

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14. Enter [-12,4,0] as Point Coordinates List and press Apply

15. Set the Action/Object/Method to Create/Curve/Revolve 16. Enter {Point 7[1 Y7 Z7]} as Axis, 360 as Total Angle, and Point 8as Point List and press Apply (with Auto Execute ON, you don’t need to press Apply if you select Point 8 from the graphics screen)

Step 3: Create a Mesh Seed 1. Open the Finite Elements (FEM) or Meshing application/tab 2. Set the Action/Object/Method to Create/Mesh Seed/Uniform 3. Set Number to 18 4. Set Curve List to Curve 3 and press Apply (with Auto Execute ON, you don’t need to press Apply if you select Curve 3 from the graphics screen) Step 4: Create the Finite Element Mesh on the pipe Geometry 1. In the Finite Elements (FEM) application/tab 2. Set the Action/Object/Method to Create/Mesh/Curve 3. Set Topology to Bar2 4. Set Curve List to Curve 3 5. Turn OFF, the Automatic Calculation toggle and press Apply 6. Set the Action/Object/Method to Sweep/Element/Extrude 7. Click Mesh Control and set Number to 3 on this form and press OK 8. Enter for Direction Vector

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9. Turn ON toggle to Delete Original Elements 10. Enter Elem 1:# for Base Entity List or select them from the graphics screen and press Apply

11. Click Mesh Control again and set Number to 12 on this form and press OK 12. Enter for Direction Vector 13. Activate the Base Entity List data box by clicking in it to give it focus 14. Change the Picking Filter to Element Edge 15. Under Preferences pull down menu, select Picking Preferences, turn ON the Enclose entire entity radio button and press the Close button 16. Select all the very right most element edges from the graphics screen and then press Apply

17. Click Mesh Control and set Number to 3 on this form and press OK 18. Enter for Direction Vector

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

19. Again select all the very right most element edges from the graphics screen and then press Apply

Step 5: Equivalence the Duplicate Nodes 1. In the Finite Elements (FEM) application/tab 2. Set the Action/Object/Method to Equivalence/All/Tolerance Cube and press Apply Step 6: Finish defining the Rigid Surfaces 1. Open the Geometry application/tab 2. Set the Action/Object/Method to Transform/Curve/Translate 3. Enter as the Direction Vector and Curve 1 2 for the Curve List and press Apply (with Auto Execute ON, you don’t need to press Apply if you select Curve 1 2 from the graphics screen) 4. Set the Action/Object/Method to Create/Surface/Curve with Option set to 2 Curve 5. Enter Curve 2 1 for the Starting Curve List and Curve 5 4 for Ending Curve List and press Apply (with Auto Execute ON, you don’t need to press Apply if you select Curve 2, then Curve 5, then Curve 1 then Curve 4 in that order from the graphics screen)

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Step 7: Create Material Properties 1. Open the Materials application/tab 2. Set the Action/Object/Method to Create/Isotropic/Manual Input 3. Give the Material Name as steel 4. Open the Input Properties form 5. Set the Constitutive Model to Linear Elastic and enter Elastic Modulus = 30.0e6, Poisson’s Ratio = 0.3 and Density = 1.0 and press OK and then press Apply 6. Open the Input Properties form

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

7. Set the Constitutive Model to Elastoplastic and enter Yield Point = 36000 and press OK and then press Apply

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Step 8: Assign Element Properties 1. Open the Element Properties application/tab 2. Set the Action/Object/Method to Create/2D/Shell with Options set to Thin/Homogeneous/Standard Formulation 3. Give the Property Set Name as pipe 4. Open the Input Properties form 5. Set the Thickness = 0.4 and press OK and then press Apply 6. Click on the Select Application Region button

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

7. Select all the element of the model graphically or type Elem 1:# in the Application Region text box. If there are entities in the Select Members data box, press Add to transfer them to the Application Region text box and then press OK and the press Apply

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Step 9: Create Fixed End on the Pipe 1. Open the Loads/BCs application/tab 2. Set the Action/Object/Type to Create/Displacement/Nodal with Option set to Standard 3. Give the New Set Name as end_disp 4. Open the Input Data form and enter for both Translations and Rotations and press OK 5. Open the Select Application Region form 6. Select all the end nodes of the pipe graphically setting the Select pull down to FEM. If there are entities in the Select Nodes data box, press Add to transfer them to the Application Region text box and then press OK and the press Apply

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

Step 10: Define the Deformable Body 1. In the Loads/BCs application/tab 2. Set the Action/Object/Type to Create/Contact/Element Uniform with Option set to Deformable Body 3. Give the New Set Name as contact_mid 4. Set the Target Element Type to 2D 5. Open the Select Application Region form

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6. Set the Select pull down to FEM and select all the pipe elements, Elem 1:#, click Add, click OK, click Apply

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

Step 11: Define the Rigid Bodies 1. In the Loads/BCs application/tab 2. Set the Action/Object/Type to Create/Contact/Element Uniform with Option set to Rigid Body 3. Give the New Set Name as contact_top 4. Set the Target Element Type to 2D 5. Open the Input Data form and turn the Flip Contact Side toggle OFF, set the Motion Control to Velocity, and enter as the Velocity (vector) and press OK 6. Open the Select Application Region form 7. Set the Select pull down to Geometry and select all the upper surface, Surface 1, click Add, click OK, click Apply 8. Repeat this step for the other surface, Surface 2, but with the Velocity (vector) set to and call it contact_bottom

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Step 12: Define the Contact Body Pairs 1. In the Loads/BCs application/tab 2. Set the Action/Object/Type to Create/Contact/Element Uniform with Option set to Body Pair 3. Give the New Set Name as top_mid 4. Open the Select Application Region form 5. Set the Mode to Existing Bodies and enter contact_top for Body 1/Master/Touched and contact_mid for Body2/Slave/Touching, click OK, click Apply 6. Repeat this step for the other body pair to be called bottom_mid, and enter contact_bottom for Body 1/Master/Touched and contact_mid for Body2/Slave/Touching

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

Step 13: Submit the Analysis 1. Open the Analysis application/tab 2. Set the Action/Object/Type to Analyze/Entire Model/Full Run 3. Enter crush400 as the Job Name 4. Press Apply - all analysis parameter defaults are used

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Chapter 1: Overview A Nonlinear Example Problem

Highlights of the MSC Nastran Analysis Once the analysis has run properly, you can inspect the resulting input file. In the Analysis application, set the Action/Object/Method to Analyze/Existing Deck/Full Run. Click on the Edit Input File button to view the input file. The following sections of the MSC Nastran bulk data file highlight the SOL 400 entries generated from the problem setup described above.

Executive Control This is the top portion of the input file up to the CEND entry. It may also contain file management commands. Note the implicit nonlinear solution is specified by the SOL 400 entry. The NASTRAN SYSTEM(316)=19 entry is necessary if you wish to attache the resulting MASTER/DBALL file for postprocessing results. $ NASTRAN input file created by the Patran 20xx.x 64-Bit $ input file translator on , at . $ Direct Text Input for Nastran System Cell Section NASTRAN SYSTEM(316)=19 $ Replace the 19 in the above line with 7 $ to get a restart DBALL instead of what is currently written $ Direct Text Input for File Management Section $ Direct Text Input for Executive Control $ Implicit NonLinear Analysis SOL 400 CEND ...

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Case Control The case control section of the MSC Nastran input file specifies the load stepping process, the type(s) of solution, which loads are applied, and what output is requested. It includes everything between the CEDN and BEGIN BULK entries. ... CEND TITLE = MSC.Nastran job created on at ECHO = NONE SUBCASE 1 STEP 1 SUBTITLE=Default Analysis Type ANALYSIS = NLSTATIC NLSTEP = 1 BCONTACT = 1 SPC = 2 Applied Load Sets & Methods LOAD = 1 DISPLACEMENT(SORT1,REAL)=ALL Output Requests SPCFORCES(SORT1,REAL)=ALL STRESS(SORT1,REAL,VONMISES,BILIN)=ALL $ Direct Text Input for this Step BEGIN BULK ...

Note the structure of the control is via a SUBCASE. Within the SUBCASE various analysis STEPs can occur. Each STEP can be of a different analysis type. More on this later. Anything specified above the SUBCASE level applies to all SUBCASEs unless changed within the SUBCASE level. Anything specified above the load STEP level applies to all STEPs within the SUBCASE unless changed within the STEP. Each STEP calls out the loads and methods to be applied during that analysis load STEP. The difference between a SUBCASE and a STEP is that a SUBCASE designates the beginning of an analysis. Each SUBCASE present is actually a separate analysis, where as a STEP is a continuation of the analysis from the ending state of the previous STEP, if there is one. In this case, there is only one SUBCASE with only one load STEP. The analysis is non-linear statics (ANALYSIS=NLSTATIC). The loading increment scheme is called out by NLSTEP=1. All contact bodies pairs are specified by BCONTACT=1. The loads applied are called out by LOAD=1 and the constraints by SPC=2. DISPLACEMENT, SPCFORCES, and STRESS are output requests.

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Bulk Data This is the main section of the MSC Nastran input file that contains the model data (FEM) contact body definition, loads and boundary conditions, and all necessary control parameters. The control parameters, methods, contact body pairs, loads and boundary conditions that are active in any given analysis STEP are those that are called out by the Case Control for the give SUBCASE/STEP combination being executed. A portion of this section is shown here with some explanations below: ... BEGIN BULK PARAM POST 1 PARAM PRTMAXIM YES BCPARA 0 NLGLUE 0 PARAM LGDISP 1 Load Incrementation NLSTEP 1 BCTABL1 0 8006 8007 BCONECT 8006 1 3 Contact Pairs BCONECT 8007 1 2 BCTABL1 1 8006 8007 $ Elements and Element Properties for region : pipe PSHELL 1 1 .4 1 1 PSHLN1 1 1 0 Element Properties C4 DCTN LDK $ Pset: "pipe" will be imported as: "pshell.1" CQUAD4 1 1 2 21 20 1 CQUAD4 2 1 3 22 21 2 CQUAD4 3 1 4 23 22 3 ... MATEP 1 PERFECT36000. VMISES MAT1 1 3.+7 .3 1. NLMOPTS LRGSTRN 1 Material Data ASSM ASSUMED $ Nodes of the Entire Model GRID 1 -12. 4. 0. Nodes/Grids GRID 2 -12. 3.7587681.368087 ... $ Loads for Load Case : Default SPCADD 2 1 Loads/BCs FORCE 1 1 0 1.-16 1. 0. 0. $ Displacement Constraints of Load Set : fix_end SPC1 1 123456 1 THRU 18 SPC1 1 123456 343 THRU 360 $ Deform Body Contact LBC set: contact_mid Contact Bodies BCBODY1 1 3D DEFORM 3 BSURF 3 1 2 3 4 5 6 7 ... ENDDATA 43645f55

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Parameters

The PARAM,POST,1 entry specifies the creation of an OUTPUT2 file for postprocessing purposes. The output requests (stress, displacement, etc.) are written to this file and it can be attached to the Patran database in the same way that a MASTER/DBALL file can in order to access the results. Load Increment and Iteration Parameters

The NLSTEP entry describes the incremental load scheme used to apply the loads and boundary conditions in a way that will avoid problems with convergence. For most problems the default values written by Patran represent the MSC Nastran SOL400 defaults, which usually provide the best chance for obtaining a converged solution. It must be activated by the equivalent Case Control. Elements and Properties

The PSHELL and PHSLN1 entries along with all the CQUAD4 entries define the shell elements and the element formulations. In this case these are standard advanced non-linear shell elements (4-node quad elements). Material Entries

This section of the MSC Nastran input file describes the material behavior for the pipe. The MAT1 entry defines the elastic part of the material and the MATEP entry describes the perfectly plastic behavior. Connectivity

All the nodes or grids of the model are listed next, which define the connectivity of the elements. Contact Entries

The BCBODY1 entry describes the deformable and rigid surfaces. Various other BC entries are also used to define contact body properties and the rigid body surfaces via NURBs data at the bottom of the bulk data portion of the file. At the top of the bulk data portion of the file is the BCTABL1 entry, which defines the contact body pairs. These are pairs for bodies that are allowed to come in contact with each other and their properties.

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Chapter 1: Overview A Nonlinear Example Problem

Result Files During or after the analysis has run, you may inspect various result files created by the analysis. From the Analysis application, set the Action/Object to Monitor/Job. Click on the View STS File... button. information summary of job: ./crush400 version: MSC Nastran 20xx.x.x, Built on , date: , ; Day Time: subcase inc cycl sepa cut cycl split separ cut rmesh time step total time wall time /step # # # # # # # # # # of of 1 |--of the inc--|-----------of the analysis-----------| the inc the job 1 0 0 0 0 0 0 0 0 0 0.0000E+00 0.0000E+00 1.00 1 1 7 0 0 7 0 0 0 0 2.0000E-02 2.0000E-02 2.00 1 2 2 0 0 9 0 0 0 0 2.0000E-02 4.0000E-02 3.00 1 3 2 0 0 11 0 0 0 0 2.0000E-02 6.0000E-02 3.00 1 4 2 0 0 13 0 0 0 0 2.0000E-02 8.0000E-02 4.00 1 5 2 0 0 15 0 0 0 0 2.0000E-02 1.0000E-01 4.00 1 6 2 0 0 17 0 0 0 0 2.0000E-02 1.2000E-01 4.00 1 7 4 0 0 21 0 0 0 0 2.0000E-02 1.4000E-01 5.00 1 8 2 0 0 23 0 0 0 0 2.0000E-02 1.6000E-01 5.00 1 9 2 0 0 25 0 0 0 0 2.0000E-02 1.8000E-01 6.00 1 10 3 1 0 28 0 1 0 0 2.0000E-02 2.0000E-01 6.00 1 11 4 2 0 32 0 3 0 0 2.0000E-02 2.2000E-01 7.00 1 12 2 0 0 34 0 3 0 0 2.0000E-02 2.4000E-01 8.00 1 13 2 0 0 36 0 3 0 0 2.0000E-02 2.6000E-01 8.00 1 14 2 0 0 38 0 3 0 0 2.0000E-02 2.8000E-01 8.00 1 15 2 0 0 40 0 3 0 0 2.0000E-02 3.0000E-01 9.00 1 16 2 0 0 42 0 3 0 0 2.0000E-02 3.2000E-01 9.00 1 17 2 0 0 44 0 3 0 0 2.0000E-02 3.4000E-01 10.00 1 18 2 0 0 46 0 3 0 0 2.0000E-02 3.6000E-01 10.00 1 19 2 0 0 48 0 3 0 0 2.0000E-02 3.8000E-01 10.00 1 20 2 0 0 50 0 3 0 0 2.0000E-02 4.0000E-01 11.00 1 21 4 1 0 54 0 4 0 0 2.0000E-02 4.2000E-01 12.00 1 22 2 0 0 56 0 4 0 0 2.0000E-02 4.4000E-01 12.00 1 23 2 0 0 58 0 4 0 0 2.0000E-02 4.6000E-01 13.00 1 24 2 0 0 60 0 4 0 0 2.0000E-02 4.8000E-01 13.00 1 25 2 0 0 62 0 4 0 0 2.0000E-02 5.0000E-01 13.00 1 26 7 1 0 69 0 5 0 0 2.0000E-02 5.2000E-01 15.00 1 27 2 0 0 71 0 5 0 0 2.0000E-02 5.4000E-01 15.00 1 28 3 0 0 74 0 5 0 0 2.0000E-02 5.6000E-01 16.00 1 29 3 0 0 77 0 5 0 0 2.0000E-02 5.8000E-01 17.00 1 30 5 1 0 82 0 6 0 0 2.0000E-02 6.0000E-01 18.00 1 31 2 0 0 84 0 6 0 0 2.0000E-02 6.2000E-01 18.00 1 32 4 2 0 88 0 8 0 0 2.0000E-02 6.4000E-01 19.00 1 33 2 0 0 90 0 8 0 0 2.0000E-02 6.6000E-01 19.00 1 34 2 0 0 92 0 8 0 0 2.0000E-02 6.8000E-01 20.00 1 35 2 0 0 94 0 8 0 0 2.0000E-02 7.0000E-01 20.00 1 36 2 0 0 96 0 8 0 0 2.0000E-02 7.2000E-01 21.00 1 37 2 0 0 98 0 8 0 0 2.0000E-02 7.4000E-01 21.00 1 38 2 0 0 100 0 8 0 0 2.0000E-02 7.6000E-01 22.00 1 39 2 0 0 102 0 8 0 0 2.0000E-02 7.8000E-01 22.00 1 40 2 0 0 104 0 8 0 0 2.0000E-02 8.0000E-01 22.00 1 41 2 0 0 106 0 8 0 0 2.0000E-02 8.2000E-01 23.00 1 42 2 0 0 108 0 8 0 0 2.0000E-02 8.4000E-01 23.00 1 43 2 0 0 110 0 8 0 0 2.0000E-02 8.6000E-01 24.00 1 44 3 1 0 113 0 9 0 0 2.0000E-02 8.8000E-01 24.00 1 45 2 0 0 115 0 9 0 0 2.0000E-02 9.0000E-01 25.00 1 46 2 0 0 117 0 9 0 0 2.0000E-02 9.2000E-01 25.00 1 47 2 0 0 119 0 9 0 0 2.0000E-02 9.4000E-01 26.00 1 48 3 1 0 122 0 10 0 0 2.0000E-02 9.6000E-01 26.00 1 49 2 0 0 124 0 10 0 0 2.0000E-02 9.8000E-01 27.00 1 50 3 1 0 127 0 11 0 0 2.0000E-02 1.0000E+00 28.00 Job ends with exit number : 0 total wall time: 29.00 total cpu time: 28.50

cpu time

1.05 2.18 2.56 2.93 3.31 3.68 4.06 4.77 5.16 5.55 6.12 6.88 7.30 7.71 8.13 8.55 8.97 9.38 9.80 10.20 10.64 11.42 11.84 12.26 12.70 13.14 14.54 14.98 15.60 16.26 17.28 17.72 18.56 19.02 19.47 19.89 20.34 20.78 21.23 21.67 22.12 22.57 23.01 23.46 24.12 24.55 25.01 25.46 26.10 26.55 27.19

max resp. type

0.0000E+00 -1.2045E-01 -1.6079E-01 -2.0114E-01 -2.4132E-01 -2.8125E-01 -3.2094E-01 -3.6072E-01 -4.0054E-01 -4.4020E-01 -4.7983E-01 -5.2187E-01 -5.7539E-01 -6.2751E-01 -6.7857E-01 -7.2883E-01 -7.7801E-01 -8.2646E-01 -8.7404E-01 -9.2091E-01 -9.6702E-01 -1.0133E+00 -1.0598E+00 -1.1063E+00 -1.1520E+00 -1.1969E+00 -1.2368E+00 -1.2785E+00 -1.3198E+00 -1.3603E+00 -1.4021E+00 -1.4458E+00 -1.4872E+00 -1.5285E+00 -1.5700E+00 -1.6111E+00 -1.6519E+00 -1.6922E+00 -1.7323E+00 -1.7719E+00 -1.8123E+00 -1.8519E+00 -1.8905E+00 -1.9288E+00 -1.9662E+00 -2.0039E+00 -2.0420E+00 -2.0799E+00 -2.1173E+00 -2.1543E+00 -2.1908E+00

disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp disp

exit DEFINITION ----= 0 job terminates normally = 1 job terminates abnormally (check Fatal Error Message in F06)

The jobname.sts file provides a status and summary of the load increment/iteration performed in this analysis. This information is useful in debugging convergence issues and obtaining accurate, efficient

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

solutions. In this problem the run completed without errors. Using the default incrementation algorithm the solution was obtained with 50 load increments. Some of the increments required up to seven (7) iterations to converge. The jobname.f06 file provides a print out of the requested output results (stress, displacement, etc.).

Results Plots The plots below show the final deformed shape of the pipe section after 100% (time=1.0) of loading. Plasticity has occurred over most of the model in contact with the rigid surfaces. Maximum stresses reaching 3.59E+4 psi occur as expected in the contact region. Also evident from the figures are high stresses equivalent to those in the contact region occurring at the constrained boundary condition. This is a consequence of the boundary condition. In a full-length pipe section, we would not expect to see a stress concentrated in this area.

Figure 1-3 Total Strains imposed on Deformed Shape

Main Index

Chapter 1: Overview A Nonlinear Example Problem

Figure 1-4 Deformed Shape and Stress Distributions

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

More Advanced Topics Of course this example shows the basics of nonlinear analysis using mostly default settings. Naturally more realistic, real-world models are going to require more than just the defaults in many cases. Here a just a few of the more advanced topics that you should become familiar with when doing non-linear analysis.

Advanced Materials There are a myriad of different material models. Besides the standard linear and perfectly plastic models shown in this exercise, you also have the options of defining the following materials: Material Types

The following material types are allowed. These are the principal materials in MSC Nastran that define the MAT1, MAT2, MAT3, MAT8, MAT9, MATORT, and MATHE material entries depending on the element types defined. The Composite Laminate is a build up of the different primary materials into plies with different primary materials, thicknesses, and orientations. 

Isotropic (MAT1)



2D & 3D Orthotropic (MAT3 / MAT8 / MATORT)



2D & 3D Anisotropic (MAT2 / MAT9)



Hyperelastic (rubber like materials) (MATHE) • Test Data or • Coefficients (five (5) different models)



Composite Laminate (PCOMP / PCOMPG / PCOMPLS / PLCOMP)

Constitutive Models Each material type, with the exception of Composite Laminate, can have multiple constitutive models associated with it, which are considered the secondary material entries to a primary MSC Nastran constitutive model. These consist of MAT4, MAT5, MATS1, MATEP, and MATF: 

Linear Elastic (MAT4 / MAT5) • including Thermal properties

Main Index



Nonlinear Elastic (MATS1)



Elastoplastic (MATEP)

Chapter 1: Overview A Nonlinear Example Problem

• Perfectly Plastic • Hardening Slope • Stress-Strain Curve 

Viscoplastic (MATVP)



Failure (MATF) • Nine (9) Failure Criteria • with Progressive Failure

See Materials, 50 for details.

Element Properties Advanced non-linear formulation elements are available for a variety of applications. Point elements, bar/line elements, shell element, 2D solid plane strain/stress and axisymmetric and 3D solid elements are all available. The material types and constitutive models available varies with element type. See Element Properties, 81 for details.

Contact Bodies, Body Pairs, and Contact Tables This is perhaps the most widely used capability of SOL 400 for nonlinear applications. We have already highlighted the creation and usage of deformable bodies and rigid bodies. In our example we defined two contact body pairs that define which bodies come into contact with which bodies, including self contact. One of the more advanced topis is to understand that within Patran there are two ways in which to define contact interaction. The default mechanism is to define contact body pairs as was shown in this example. The other mechanism is to define a contact table, which is basically a matrix or spreadsheet with each cell representing a contact body pair. Each off-diagonal terms represent a pair of bodies that can come into

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

contact. Each diagonal term represents self-contact of a single deformable body. Naturally only the upper (or lower) portion of the matrix needs to be filled out. And rigid bodies never come into contact with themselves or other rigid bodies. So those cells or inaccessible. This is what the contact table looks like for this example problem.

By default every body may come into contact with every other body in including itself. Properties can be set for each individual body pair by clicking on or highlighting a cell in the table and changing the settings. Glued contact can be defined also via the table or using the default body pair mechanism. See Contact Table, 345 for details.

Main Index

Chapter 1: Overview A Nonlinear Example Problem

In order to use a contact table instead of contact body pairs, you must turn on the toggle on the Contact Control Parameters form. See Contact Control Parameters, 302 for details.

When you should use a contact table versus contact body pairs is a matter of preference. Contact body pairs are actual entities stored in the database. You can define as many as you want and include them in Patran load cases and activate them as needed for an analysis. They are used only if the Load Step is associated to a load case that contains the body pairs. Each body pair only defines the interaction between two contact bodies (or itself ). If you have very few contact bodies or if the body pairs are very specific and you know that only those bodies will ever come into contact with themselves, then this may be the best mechanism to use. Body pairs also can share common properties. So you may define one set of body pair properties and then assign them to multiple body pairs. Defining contact interaction via a contact table is somewhat the opposite. Each contact table is only associated with a Load Step. Therefore they are actually parameters stored in the database for a Load Step associated to an analysis job. Each contact table defines the interaction between all the contact bodies in the model. From this standpoint it can be cumbersome to use if you have a lot of contact bodies, especially if you need to view and change properties for many of the pairs. On the other hand, a matrix view of your contact interaction is quite handy. You can switch back and forth between using contact tables and contact body pairs as long as you do not redefine your Load Steps. If you turn the Use Contact Table toggle ON and then define you Load Steps with contact table interaction, the Contact Table definitions get stored with the Load Cases. Then you can turn the toggle OFF and submit the job. If there are contact body pairs defined, the body pairs will be used in the analysis. If you turn the toggle back ON, then the contact table will be used instead to define the contact interaction. But be aware that if you redefine the Load Step with the toggle OFF, the contact table definition will be lost.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

Load Steps This is probably the next most used feature of SOL 400 non-linear analysis. This feature allows you to define the sequence of analysis steps in your non-linear analysis. Perhaps an example is best used to illustrate this. Let’s assume that in our example problem of the pipe crush that we first would like to know the natural frequencies of the pipe before it is plastically deformed. The we want to plastically deform it and afterward, determine how the natural frequencies change in its deformed shape. This is sometimes referred to as perturbation analysis. The way to set up this analysis is to create two Load Steps. The first Load Step is a modal analysis. The second Load Step is a non-linear analysis. In order to do the first modal analysis, without the perturbation, we setup a separate MSC Nastran SUBCASE and only include the modal step. The second SUBCASE includes the nonlinear step followed by the modal step. This is how you would set it up. Step 1: Create a Modal Step 1. Open the Analysis application/tab 2. Click on the Load Step... button 3. Give the Load Step the name, Modal 4. Select Default as the Available Load Case 5. Change the Analysis Type to Normal Modes

Main Index

Chapter 1: Overview A Nonlinear Example Problem

6. Press Apply - this creates the step with default parameters - first 10 modes extracted

Step 2: Create a Nonlinear Step 1. Still in the Load Steps form, change the Load Step the name, Nonlinear 2. Change the Analysis Type to Static 3. Select Default as the Available Load Case 4. Press Apply - this creates the step with default parameters Step 3: Assemble the Load Step 1. Open the Load Step Select... form 2. Right Mouse Button (RMB) click on the job name crush400 on the left-hand side of the form inside the Subcase/Step Configuration tree widget and select Add Subcase. 3. You should have Subcase1 and Subcase2 showing. Highlight Subcase1 and click on Modal from the Available Load Steps list box. 4. Highlight Subcase 2 and click on Nonlinear and then click on Modal.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

5. You should see the set up as below. If there are any Load Steps listed under Subcase1 or Subcase2 that should not be there, RMB click on them and select Remove Load Step.

6. Close the form and press the Apply button on the Analysis form. When the job is done running you can inspect the results and notice the first natural frequency of the first mode from SUBCASE 1 with no perturbation and the frequency from SUBCASE 2, STEP 2 after the perturbation. By opening the input file in an editor as done before, you can now see the Case Control setup as follows: ... CEND SUBCASE 1 SUBTITLE=Modal Step - no perturbation ANALYSIS = MODES METHOD = 1 ... SUBCASE 2 STEP 1 SUBTITLE=Pipe Crush Plastic Deformation ANALYSIS = NLSTATIC NLSTEP = 2 ... STEP 2 SUBTITLE=Modal Step - after perturbation ANALYSIS = MODES METHOD = 1 BCONTACT = ALLBODY ... BEGIN BULK ...

Main Index

Chapter 1: Overview A Nonlinear Example Problem

See Load Steps, 314 and Load Step Select, 383 for details. Have fun exploring and using the MSC Nastran Implicit Nonlinear Preference in Patran.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear A Nonlinear Example Problem

Main Index

Chapter 2: Building A Model MSC Nastran Implicit Nonlinear (SOL 600) User’s GuidePatran MSC Nastran Preference Guide - Implicit Nonlinear

2

Main Index

Building A Model 

Coordinate Frames



Nodes and Elements



Multi-point Constraints



Materials



Element Properties



Loads and Boundary Conditions



Load Cases



Contact Bodies

42 42 44

50

243 244

81 207

42

Patran MSC Nastran Preference Guide - Implicit Nonlinear Coordinate Frames

Coordinate Frames Coordinate frames are defined in the Geometry application. Click on the Geometry tab or switch on the main Patran form. For details on how to use this application, please see Introduction to Geometry Modeling (Ch. 1) in the Geometry Modeling - Reference Manual Part 2.

Any defined coordinate frame generates 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 are translated into the MSC Nastran input file. For more information on creating coordinate frames see Creating Coordinate Frames (p. 447) 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.

Nodes and Elements Nodes and element make up the finite element model itself. The Finite Elements Application allows the definition of basic finite element construction.

For more information on how to create finite element meshes, see Mesh Seed and Mesh Forms (p. 22) in the Reference Manual - Part III.

Main Index

Chapter 2: Building A Model Nodes and Elements

Nodes Nodes in Patran generate unique GRID bulk data entries in the MSC Nastran input deck. Nodes can be created either directly using the Node object or indirectly using the Mesh object. Each node has associated reference (CP field of GRID entry) and analysis (CD field of GRID entry) coordinate frames. 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. See Translation Parameters, 291. The GRID ID is taken directly from the assigned Patran node ID. The X1, X2, and X3 fields are defined in the specified CP coordinate frame. If no reference frame is assigned, the global system is used. The PS and SEID fields on the GRID entry are left blank. To create nodes when meshing with the desired coordinate frames, use the Node Coordinate Frames... form to set the coordinate frames as desired. To change the analysis or reference coordinate frames of a node, set Action to Modify, Object to Node, and Method to Edit.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Multi-point Constraints

Elements The type of MSC Nastran element created is not determined until the element properties are assigned (for example, shell or 2D solid). See Element Properties, 81 for details concerning the MSC Nastran element types. Elements can be created either directly using the Element object or indirectly using the Mesh object in the Finite Elements application. Again, please see Mesh Seed and Mesh Forms (p. 22) in the Reference Manual - Part III for details on how to make a finite element mesh.

Multi-point Constraints To access and define multi-point constraints (MPCs), first ensure that Analysis Code and Type are set properly to Implicit Nonlinear. See Setting the Analysis Code and Type, 2. MPCs are defined in the Finite Element application. Click on the Finite Element (or Meshing) tab or switch on the main Patran form. For details on how to use this application, please see Introduction to Finite Element Modeling (Ch. 1) in the Reference Manual - Part III.

When the application form appears, set the Object to MPC and the Type menu to the desired MPC type.

To define an MPC, you must open the Define Terms... form, set that as necessary, and then press the Apply button. For specific details on how to use this application, please see Creating MPCs (Ch. 3) in the Reference Manual - Part III. A list of supported MPC types is given in the table below.

Main Index

Chapter 2: Building A Model Multi-point Constraints

Table 2-1 Supported Multi-Point Constraints (MPCs) Type

Bulk Data

Description

RBE2

RBE2

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 (DOF) 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. See RBE2 MPCs, 46.

RBE3

RBE3

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. See RBE3 MPCs, 47.

Overclosure

BOLT

Creates a BOLT entry. See RBE3 MPCs, 47 and Bolt Pre-load (Ch. 11) in the Patran Reference Manual.

Degrees of Freedom Whenever a list of degrees of freedom is expected for an MPC term, a list box containing the valid degrees of freedom is displayed on the form. The following degrees of freedom are supported: Degree of Freedom

Main Index

Description

UX

X Translation (or R in cylindrical or spherical systems)

UY

Y Translation (or θ in cylindrical or spherical systems)

UZ

Z Translation (or ϕ in spherical systems)

RX

Rotation about X (or R in cylindrical or spherical systems)

RY

Rotation about Y (or θ in cylindrical or spherical systems)

RZ

Rotation about Z (or ϕ in spherical systems)

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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. RBE2 MPCs This subordinate MPC form appears when the Define Terms... button is selected with RBE2 as the MPC type.

Table 2-2 RBE2 MPC Terms Term

Main Index

Bulk Data (field)

Description

Dependent Terms (1)

RBE2 (GMi, CM)

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)

RBE2 (GN)

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

RBE2 (ALPHA)

Thermal Expansion Coefficient from the main Finite Element form.

Chapter 2: Building A Model Multi-point Constraints

Note: See Creating MPCs (Ch. 3) in the Reference Manual - Part III to understand how this forms works. You must press the Apply button on the many Finite Elements form in order to actually create the MPC.

RBE3 MPCs This subordinate MPC form appears when the Define Terms... button is selected with RBE3 as the MPC

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Multi-point Constraints

type.

Table 2-3 RBE3 MPC Terms Term

Bulk Data (field)

Dependent Terms (No Max)

RBE3 (GMi, CMi, REFGRID, REFC)

Independent Terms (No Max)

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

Main Index

Description Holds the dependent term information. Defines the GMi and CMi fields on the RBE3 entry. The first dependent term is treated as the reference node, REFGRID and REFC. The rest of the dependent terms become the GMi and CMi components.

Thermal Expansion Coefficient from the main Finite Element form.

Chapter 2: Building A Model Multi-point Constraints

Note: See Creating MPCs (Ch. 3) in the Reference Manual - Part III to understand how this works. You must press the Apply button on the many Finite Elements form in order to actually create the MPC.

Overclosure This subordinate MPC form appears when the Define Terms... button is selected with Overclosure the MPC type..

Table 2-4 BOLT MPC Terms Term

Main Index

Bulk Data (field)

Description

Dependent Terms (No Max)

BOLT (BOTTOM, GBi)

Holds the dependent term information. Defines the BOTTOM nodes (GBi) of the bolt intersection with the structure (one node per line). The control grid (GRIDC) should NOT be one of these nodes.

Independent Terms (No Max)

RBE3 (TOP, GTi, GRIDC)

Holds the independent term information. Defines the TOP nodes of the bolt intersection with the structure. The control node (GRIDC) MUST always be the second node and the same for each in the list for any independent term defined (two nodes per line).

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Note: See Creating MPCs (Ch. 3) in the Reference Manual - Part III to understand how this works. You must press the Apply button on the many Finite Elements form in order to actually create the MPC. See also Bolt Pre-load (Ch. 11) in the Patran Reference Manual. Materials To define materials, first ensure that the Analysis Code and Type are set properly to Implicit Nonlinear. See Setting the Analysis Code and Type, 2. Modeling of nonlinear material behavior is a critical component to obtain the structural response of structures; especially, when either the loads are large, the temperatures are high, and/or a non-metallic material is used. MSC Nastran SOL 400 provides a variety of models and, in some cases, multiple numerical implementation of these models. Details of how to use the Materials application are described in Material Library (p. 61) in the Patran Interface to MSC Nastran Preference Guide. This chapter describes each available material type definable for this analysis preference. The materials shown in the following table are available for the Implicit Nonlinear preference.

Material Constitutive Models The table below lists each supported material type and its constitutive models. Each is described in the next section.

Main Index

Chapter 2: Building A Model Materials

Table 2-5 Supported Material Constitutive Models Objects Isotropic

Constitutive Model

Option 1

Option 2

Option 3

Option 4

Linear Elastic, 55 Nonlinear Elastic, 61 Elastoplastic, 62

Stress/Strain Curve

Von Mises

Isotropic Kinematic Combined

None Piecewise Linear Cowper-Symonds

Power Law Rate Power Law Johnson-Cook Kumar Chaboche

None

Mohr-Coulomb Parabolic Mohr Hill Yield Barlat

Isotropic Kinematic Combined

None Piecewise Linear Cowper-Symonds

Implicit Creep

Isotropic Kinematic Combined

Viscoplastic Von Mises

Von Mises Mohr-Coulomb Parabolic Mohr Hill Yield Barlat

None

None Piecewise Linear Cowper-Symonds

Implicit Creep

None

Viscoplastic Von Mises

Hardening Slope

Perfectly Plastic

Main Index

Viscoplastic, 71

Coefficients

Failure 1, Failure 2, Failure 3, 72

Maximum Stress Maximum Strain Hill Hoffman Tsai-Wu Hashin Puck Hashin-Tape Hashin-Fabric

None Gradual (not available for Failure2/3) Immediate (not available for Failure2/3)

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Materials

Table 2-5 Supported Material Constitutive Models (continued) Objects 2D Orthotropic 3D Orthotropic 2D Anisotropic 3D Anisotropic

Constitutive Model

Option 1

Main Index

Option 3

Option 4

Linear Elastic, 55 Elastoplastic, 62

Stress/Strain Curve Hardening Slope

Perfectly Plastic

Hyperelastic

Option 2 Von Mises Hill Yield Barlat Implicit Creep

Isotropic Kinematic Combined

None Piecewise Linear Cowper-Symonds

Implicit Creep

Isotropic Kinematic Combined

Viscoplastic Von Mises

Von Mises Hill Yield Barlat

None

None Piecewise Linear Cowper-Symonds

Implicit Creep

None

Viscoplastic Von Mises

Viscoplastic, 71

Coefficients

Failure 1, Failure 2, Failure 3, 72

Maximum Stress Maximum Strain Hashin-Fabric Hill Hoffman Tsai-Wu Hashin Puck Hashin-Tape Hashin-Fabric

None (only option for Anisotropic materials) Gradual (not available for Failure2/3) Immediate (not available for Failure2/3)

Hyperelastic, 74

Nearly Incompressible

Coefficients

Mooney-Rivlin Ogden Foam Arruda-Boyce Gent

Order: 1-5

Test Data

Mooney-Rivlin

Order: 1-5

Chapter 2: Building A Model Materials

Table 2-5 Supported Material Constitutive Models (continued) Objects Cohesive, 77

Constitutive Model Bilinear

Exponential

LinearExponential Composite

Main Index

Laminate, 80

Option 1 





Secant

Secant

Secant

Option 2

Option 3



No



None



Yes



Automatic



User Defined



No



None



Yes



Automatic



User Defined



Automatic



User Defined



Yes

Option 4 

Keep



Keep



Keep

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Materials

Material Input Properties To input material properties for a particular material type and its constitutive model, set the Object to the material type of interest, click on the Input Properties... button on the Materials application form. The following form appears and differs for each material type. Set the Constitutive Model and its options on this form, enter the necessary data, and press the Apply button on the Materials application form. You must do this for each constitutive model you wish to define for the material you are creating.

Material Status On the Material application form there is another button just under the Input Properties.. button called Change Material Status... You can use this to activate and deactivate material constitutive models for a particular material that has been defined. Open the form and move the Active Constitutive Models to the

Main Index

Chapter 2: Building A Model Materials

Inactive Constitutive Models list box. Any constitutive models in the Inactive Constitutive Models list box are ignored by any subsequent analysis.

Linear Elastic The Input Properties form displays the following for linear elastic properties. The translator produces the corresponding bulk data entries. Temperature dependency is defined using material fields defined under the Fields Application (Ch. 6) in the Patran Reference Manual and placed on TABLEM1 entries.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Materials

Table 2-6 Isotropic* Linear Elastic Material Properties Property

Main Index

Bulk Data (field)

Description

Elastic Modulus

MAT1 (E) MATT1

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

Poisson Ratio

MAT1 (NU) MATT1

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

Shear Modulus

MAT1 (G) MATT1

Shear modulus. Can be temperature dependent.

Density

MAT1 (RHO) MATT1 MAT4 (RHO) MATT4

Mass density. Can be temperature dependent.

Thermal Expansion Coefficient

MAT1 (A) MATT1

Thermal coefficient of expansion. Can be temperature dependent.

Structural Damping Coefficient

MAT1 (GE) MATT1

Structural damping coefficient. Can be temperature dependent.

Reference Temperature

MAT1 (TREF)

Reference temperature. Other material properties are evaluated at this reference temperature when temperature dependencies are detected.

Thermal Conductivity

MAT4 (K) MATT4

Thermal conductivity. Can be temperature dependent.

Specific Heat

MAT4 (CP) MATT4

Heat capacity per unit mass at constant pressure (specific heat). Can be temperature dependent.

Heat Transfer Coefficient

MAT4 (H) MATT4

Free convection heat transfer coefficient. Can be temperature dependent.

Dynamic Viscosity

MAT4 (μ) MATT4

Dynamic viscosity. Can be temperature dependent.

Reference Enthalpy

MAT4 (REFENTH)

Reference enthalpy.

Chapter 2: Building A Model Materials

Table 2-6 Isotropic* Linear Elastic Material Properties (continued) Property

Bulk Data (field)

Description

Phase Change Temperature

MAT4 (TCH)

Lower temperature limit at which phase change region is to occur.

Phase Change Temperature Range

MAT4 (TDELTA)

Total temperature change range within which a phase change is to occur.

Latent Heat

MAT4 (QLAT)

Latent heat of fusion per unit mass associated with the phase change.

Heat Generation Multiplier

MAT4 (HGEN) MATT4

Heat generation capability used with QVOL entries. Can be temperature dependent.

* Most element types accept Isotropic material definitions.

Table 2-7 2D Orthotropic* Linear Elastic Material Properties Property

Main Index

Bulk Data (field)

Description

Elastic Modulus 11/22

MAT8 (E1/E2) MATT8

Elastic moduli in longitudinal and lateral directions, respectively. Can be temperature dependent.

Poisson Ratio 12

MAT8 (NU12) MATT8

Poisson’s ratio for uniaxial loading in 1-direction. Can be temperature dependent. Should be between -1.0 and 0.5.

Shear Modulus 12/23/13

MAT8 (G12/G1Z/G2Z) In plane-shear modulus, transverse shear modulus in 1-Z MATT8 plane and 2-Z plane, respectively. Can be temperature dependent.

Density

MAT8 (RHO) MATT8 MAT5 (RHO) MATT5

Mass density. Can be temperature dependent.

Thermal Expansion Coefficient 11/22

MAT8 (A1/A2) MATT8

Thermal coefficients of expansion in i-direction. Can be temperature dependent.

Structural Damping Coefficient

MAT8 (GE) MATT8

Structural damping coefficient. Can be temperature dependent.

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Table 2-7 2D Orthotropic* Linear Elastic Material Properties (continued) Property

Bulk Data (field)

Description

Reference Temperature

MAT8 (TREF)

Reference temperature. Other material properties are evaluated at this reference temperature when temperature dependencies are detected.

Thermal Conductivity Kx/Kr, Ky/Kz

MAT5 (KXX/KYY) MATT5

Terms of thermal conductivity matrix. Can be temperature dependent.

Specific Heat

MAT5 (CP) MATT5

Heat capacity per unit mas at constant pressure (specific heat). Can be temperature dependent.

Heat Generation Multiplier

MAT5 (HGEN) MATT5

Heat generation capability used with QVOL entries. Can be temperature dependent.

* Shell type elements and 2D solid plane stress elements accept 2D Orthotropic materials.

Table 2-8 3D Orthotropic* Linear Elastic Material Properties Property

Main Index

Bulk Data (field)

Description

Elastic Modulus ii

MATORT (E1/E2/E3) MATTORT

Poisson Ratio ij

MATORT (NU12/23/31) MATTORT

Shear Modulus ij

MATORT (G12/G23/G31) MATTORT

In plane-shear moduli for plane 1-2, 2-3, and 3-1, respectively. Can be temperature dependent.

Density

MATORT (RHO) MATTORT MAT5 (RHO) MATT5

Mass density. Can be temperature dependent.

Thermal Expansion Coefficient ii

MATORT (A1/A2/A3) MATTORT

Thermal coefficients of expansion in i-direction. Can be temperature dependent.

Structural Damping Coefficient

MATORT (GE) MATTORT

Structural damping coefficient. Can be temperature dependent.

Elastic moduli in longitudinal, lateral and thickness directions, respectively. Can be temperature dependent. Poisson’s ratio for uniaxial loading in 1,2, and 3directions, respectively. Can be temperature dependent. Should be between -1.0 and 0.5.

Chapter 2: Building A Model Materials

Table 2-8 3D Orthotropic* Linear Elastic Material Properties (continued) Property

Bulk Data (field)

Description

Reference Temperature

MATORT (TREF)

Reference temperature. Other material properties are evaluated at this reference temperature when temperature dependencies are detected.

Thermal Conductivity Kx, Ky, Kz

MAT5 (KXX/KYY/KZZ) MATT5

Terms of thermal conductivity matrix. Can be temperature dependent.

Specific Heat

MAT5(CP) MATT5

Heat capacity per unit mas at constant pressure (specific heat). Can be temperature dependent.

Heat Generation Multiplier

MAT5(HGEN) MATT5

Heat generation capability used with QVOL entries. Can be temperature dependent.

* 3D solid elements, most 2D solid plane stress/strain/axisymmetric and some shell type elements accept 3D Orthotropic materials. Table 2-9 2D Anisotropic* Linear Elastic Material Properties Property

Main Index

Bulk Data (field)

Description

Stiffness ij

MAT2 (G11-G33) MATT2

Density

MAT2 (RHO) MATT2 MAT5 (RHO) MATT5

Thermal Expansion Coefficient 11/22/12

MAT2 (A1/A2/A3) MATT2

Terms of the thermal coefficients vector. Can be temperature dependent.

Structural Damping Coefficient

MAT2 (GE) MATT2

Structural damping coefficient. Can be temperature dependent.

Terms of the material property matrix. Can be temperature dependent. Mass density. Can be temperature dependent.

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Table 2-9 2D Anisotropic* Linear Elastic Material Properties Property

Bulk Data (field)

Description

Reference Temperature

MAT2 (TREF)

Reference temperature. Other material properties are evaluated at this reference temperature when temperature dependencies are detected.

Thermal Conductivity Kxx/Kxy/Kyy

MAT5 (KXX/KYY) MATT5

Terms of thermal conductivity matrix. Can be temperature dependent.

Specific Heat

MAT5 (CP) MATT5

Heat capacity per unit mass at constant pressure (specific heat). Can be temperature dependent.

Heat Generation Multiplier

MAT5 (HGEN) MATT5

Heat generation capability used with QVOL entries. Can be temperature dependent.

* Shell type elements and some 2D solid plane strain/stress/axisymmetric elements accept 2D Anisotropic materials.

Table 2-10 3D Anisotropic* Linear Elastic Material Properties Property

Main Index

Bulk Data (field)

Description

Stiffness ij

MAT9 (G11-G66) MATT9

Density

MAT9 (RHO) MATT9 MAT5 (RHO) MATT5

Thermal Expansion Coefficient ij

MAT9 (A1/A2/A3) MATT9

Terms of the thermal coefficients vector. Can be temperature dependent.

Structural Damping Coefficient

MAT9 (GE) MATT9

Structural damping coefficient. Can be temperature dependent.

Terms of the material property matrix. Can be temperature dependent. Mass density. Can be temperature dependent.

Chapter 2: Building A Model Materials

Table 2-10 3D Anisotropic* Linear Elastic Material Properties (continued) Bulk Data (field)

Property

Description

Reference Temperature

MAT9 (TREF)

Reference temperature. Other material properties are evaluated at this reference temperature when temperature dependencies are detected.

Thermal Conductivity Kij

MAT5 (KXX-KZZ) MATT5

Terms of thermal conductivity matrix. Can be temperature dependent.

Specific Heat

MAT5(CP) MATT5

Heat capacity per unit mass at constant pressure (specific heat). Can be temperature dependent.

Heat Generation Multiplier

MAT5(HGEN) MATT5

Heat generation capability used with QVOL entries. Can be temperature dependent.

* Only 3D solid elements accept 3D Anisotropic materials.

Nonlinear Elastic The Input Properties form displays the following for nonlinear elastic properties. A stress-strain curve or a termperature dependent stress-strain curve is defined using the Fields Application (Ch. 6) in the Patran Reference Manual. Table 2-11 Isotropic Nonlinear Elastic* Material Properties Property Stress/Strain Curve

Bulk Data (field) MATS1 (TID, TYPE=NLELAST) TABLES1 TABLEST

Main Index

Description Defines the nonlinear elastic stress-strain curve. You must select a field from the list box. It must be a strain or strain/temperature dependent field. The first point of the material field should be the origin† (at zero stress, zero strain) and the second point must be at the initial yield point. This material curve is nonlinear-elastic; meaning that in both loading and unloading, the material behavior follows the stress-strain curve as defined (no hysteresis or permanent plastic deformation). A temperature independent stress-strain definition results in a single TABLES1entry referenced by the MATS1 TID field. A temperature dependent stress-strain definition references a TABLEST entry in the TID field, which in turn references each TABLES1 entries for each stress-strain relation at each defined temperature.

61

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Materials

* This material definition is only available for Isotropic materials. Most element types accept Isotropic material definitions. It is not recommended that both nonlinear elastic and elastoplastic constitutive models be active or defined for the same material as this is incompatible and results in a fatal error in MSC Nastran. You will be warned if this is the case. † If the first point is not (0,0), then a (0,0) point is inserted when the TABLES1 is created in the input file.

Elastoplastic1 The Input Properties form displays the following for elastoplastic properties. Use this form to define the data describing plastic behavior of a material. There are three main elastoplastic definition types. Each is described in the tables below. Table 2-12 Elastoplastic Material Properties (Stress/Strain Curve) Property Stress/Strain Curve

Bulk Data (field) MATEP (FORM=TABLE, FID) TABLES1 TABLEST

Description Defines the stress-strain curve. You must select a field from the list box. It must be a material field of stress versus independent variable(s) strain or strain/temperature or strain/strain-rate, or strain/temperature/strain-rate. The first point of the material field should be the Cauchy (true) stress vs. plastic true strain and the TABLES1 is written with TYPE=2*. A temperature independent stress-strain definition results in a single TABLES1entry referenced by the MATEP FID field. A temperature dependent stress-strain definition references a TABLEST entry in the FID field, which in turn references each TABLES1 entries for each stress-strain relation at each defined temperature. An additional TABLES1 is written if the field is also strain-rate dependent. See the discussion on Stress vs Strain vs Strain-Rate vs Temperature Fields, 66 below.

* If the first point is (0,0) or in other words, Cauchy (true) stress vs. total true strain, the TABLES1 entry is written with TYPE=1 and MSC Nastran converts the stress-strain definition to true stress vs. plastic true strain internally. If the first is (!0,!0), or in other words, both values are not zero, then it is assumed that this definition is also true stress vs. total true strain and a (0,0) point is add at the start of the table. Only if the first point is (!0,0), or in other words, the stress is nonzero and the strain is zero, is it assumed that the definition is true stress vs. plastic true strain and TYPE=2 is used. 1

Main Index

This material definition is available for Isotropic, Orthotropic, and Anisotropic materials. It is not recommended that both nonlinear elastic and elastoplastic constitutive models be active or defined for the same material as this is incompatible and results in a fatal error in MSC Nastran. You will be warned if this is the case.

Chapter 2: Building A Model Materials

Table 2-13 Elastoplastic Material Properties (Hardening Slope) Property

Bulk Data (field)

Description

Hardening Slope

MATEP (FORM=SLOPE, H)

Work hardening slope (H) - slope of stress versus plastic strain, sometimes referred to as the plasticity modulus, defined in units of stress. For an elastic-perfectly plastic case (H=0), use the Perfectly Plastic data input option. This can be a scalar value or a temperature dependent field of slope versus temperature.

Stress at Yield

MATEP (Y0)

Initial yield stress or hydrostatic stress for Mohr-Coulomb material. This can be a scalar value or a temperature dependent material field of yield stress versus temperature or yield stress versus strain-rate and/or temperature if the Strain Rate Method is Piecewise Linear. See the discussion on Stress vs Strain vs Strain-Rate vs Temperature Fields, 66 below.

or Yield Point

Table 2-14 Elastoplastic Material Properties (Perfectly Plastic*) Property Stress at Yield or Yield Point

Bulk Data (field) MATEP (FORM=SLOPE, Y0)

Description Initial yield stress or hydrostatic stress for Mohr-Coulomb material. This can be a scalar value or a temperature dependent material field of yield stress versus temperature or yield stress versus strain-rate and/or temperature if the Strain Rate Method is Piecewise Linear. See the discussion on Stress vs Strain vs Strain-Rate vs Temperature Fields, 66 below.

* This is essentially the same as Hardening Slope with H=0. Other settings available for elastoplastic material definitions are described in the table below.

Main Index

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Table 2-15 Elastoplastic Material Properties (Yield Function*) Property

Bulk Data (field)

Description

Yield Function MATEP (RYIELD)

Valid Yield Functions are Von Mises, Mohr-Coulomb, Parabolic Mohr-Coulomb, Hill Yield, Barlat, and Implicit Creep. Some require additional input as described in this table.

Alpha

MATEP (“PRESS” OPTION=LIN, ALPHA)

Alpha parameters for Mohr-Coulomb yield function.

Beta

MATEP (“PRESS” OPTION=PBL, BETA)

Beta parameters for Parabolic Mohr-Coulomb yield function.

Stress ii Yield Ratio

MATEP (“ANISO” Rij)

Stress ratios of initial yield stresses in various material directions to the reference yield stress from the FID or Y0 field used with Hill Yield.

M, C1, C2, C3, C6

MATEP (“ANISO”, M, C1, C2, C3, C6)

M, C1, C2, C3, and C6 coefficients used with Barlat yield function.

Viscoplastic Param 1& 2

MATEP (Vp1, Vp2)

A list of viscoplastic parameters used with Implicit Creep yield function. See Viscoplastic, 71 for more information.

EQV (von Mises) Tensile YS

MATEP (VMISES)

Equivalent (von Mises) tensile yield stress sed with Implicit Creep yield function. Overrides any similar entry made for this material elsewhere. See Viscoplastic, 71 for more information.

* Mohr-Coulomb and Parabolic Mohr-Coulomb are only available for Isotropic materials.

Main Index

Chapter 2: Building A Model Materials

Table 2-16 Elastoplastic Material Properties (Hardening Rule*) Property

Bulk Data (field)

Description

Hardening Rule

MATEP (WKHARD)

Valid Hardening Rules are: Isotropic, Kinematic, Combined (Isotropic and Kinematic), Power Law, Rate Power Law, Johnson-Cook, Kumar, and Chaboche. Some require additional input as described in this table.

Coefficient A, B Exponent M, N

MATEP (“PWRLAW”, A, B, M, N)

Coefficients A and B and Exponents M and N for the Power Law and Rate Power Law hardening rules.

Initial Equivalent Strain

MATEP (“PWRLAW”, ε0)

The initial equivalent strain for the Power Law hardening rule.

Minimum Yield Stress

MATEP (“PWRLAW”, σ0)

The minimum yield stress for the Rate Power Law hardening rule.

Coefficient A, B, C Exponent M, N

MATEP (“JHCOOK”, A, B, C, M, N)

Coefficients A, B, C and Exponents M and N for the Johnson-Cook hardening rule.

Room Temperature

MATEP Room (ambient) temperature for the Johnson-Cook (“JHCOOK”, TROOM) hardening rule.

Melt Temperature

MATEP (“JHCOOK”,TMELT)

Melting temperature for the Johnson-Cook hardening rule.

Reference Strain Rate

MATEP (“JHCOOK”, ε0 DOT)

Reference strain rate for the Johnson-Cook hardening rule.

Coefficient A Coefficient B0-B6 Exponent N

MATEP (“KUMAR”, Β0−Β6, Α, Ν)

Coefficients A, B0, B1, B2, B3, B4, B5, and B6 and Exponent N for the Kumar hardening rule. A, B0, and N can be temperature dependent and write TABLEM1 if a material field is provided.

R0 Rinf or Q0 Coefficient B, C, Gamma, Kappa, N, Qm, MU, ETA

MATEP (“CHABOCHE”, R0, Rinf, B, C, Gam, Kap, N

R0 for isotropic hardening, Rinfinity for isotropic hardening (or Q0 in case of using plastic strain-range memorization), coefficients B for isotropic hardening, C for kinematic hardening, Gamma and Kappa for kinematic hardening, N for viscosity model, Qm for isotropic hardening, MU for isotropic hardening, and ETA to introduce progressive memory. These are used for Chaboche hardening rule.

* Not applicable for Perfectly Plastic materials. Only the Von Mises Yield Function allows for Hardening Rules other than the standard Isotropic, Kinematic, or Combined and then only for Isotropic materials.

Main Index

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Table 2-17 Elastoplastic Material Properties (Strain Rate Method*) Property

Bulk Data (field)

Description

Strain Rate Method

MATEP (“REFFECT”)

Valid Strain Rate Methods are: None, Piecewise Linear†, Cowper-Symonds, Viscoplastic and Von Mises. Some require additional input as described in this table. See the discussion on Stress vs Strain vs Strain-Rate vs Temperature Fields, 66 below.

Denominator C

MATEP (“REFFECT”, OPTION=COWPER, C)

Constant C for Cowper and Symonds strain rate model.

Inverse Exponent P

MATEP (“REFFECT”, OPTION=COWPER, P)

Constant P for Cowper and Symonds strain rate model.

* Strain Rate Methods can only be used with Isotropic, Kinematic, and Combined (Isotropic and Kinematic) hardening rules. † For the Piecewise Linear strain rate method, the OPTION=TABLE is specified in the “REFFECT” line of the MATEP entry. The field that is selected must be a strain/strain-rate dependent field, in which case the RTID field points to a TABLES1 entry. The table defines yield stress as a function of strain-rate starting from zero strain-rate. To define this using a field, a 2D field must be created with strain and strain-rate as the variables. The strain-rate values must start at zero (columns). The first column under the first strain-rate must define the stress-strain curve in terms of true stress vs. plastic true strain where the first stress-stain point is (!0,0) as described in Elastoplastic Material Properties (Stress/Strain Curve), 62. The values in first row correspond to the yield stress at each strain-rate. Only the first column of stress data defining the stress-strain curve and the first row defining the yield-stress vs. strain-rate are extracted from the field. The other data in the other column/row cells of the spreadsheet defining the field are ignore, but may have to be input to create a valid field. Stress vs Strain vs Strain-Rate vs Temperature Fields

It is important to understand how to create proper fields when specifying stress-strain curves and yield stress that may or may not be dependent on temperature and/or strain rate. When the Nonlinear Data Input is Hardening Slope or Perfectly Plastic, the yield stress can be defined as a scalar value or by a temperature and/or strain-rate dependent field. When the Nonlinear Data Input is Stress/Strain Curve, the data must be defined by a field of stress vs strain. The stress/strain curve can also be temperature and/or strain-rate dependent. In order to use a strain-rate dependent field, the Strain Rate Method must be set to Piecewise Linear. The table below summarizes with applicable footnotes.

Main Index

Chapter 2: Building A Model Materials

Table 2-18 Allowable Strain, Strain-Rate, Temperature Fields Nonlinear Data Input Field Independent Variables

Stress/Strain Curve

Hardening Rule

Perfectly Plastic

Strain only (1D field)*

YES

NO

NO

Strain-Rate only (1D field)†

NO

YES

YES

Temperature only (1D field)‡

NO

YES

YES

Strain-Rate & Temperature (2D field)**

NO

YES

YES

Strain & Temperature (2D field)††

YES

NO

NO

Strain & Strain-Rate (2D field)‡‡

YES

NO

NO

Strain & Strain-Rate & Temperature (3D)***

YES

NO

NO

* Only allowable for Stress/Strain Curve data. As mentioned above, this data must be a 1D stress versus strain (independent variable) field of true stress vs true plastic strain, i.e., the first data pair is (0,!0) defining the yield stress at zero plastic strain. Or it can be true stress versus total strain, i.e., the first data pair is (0,0) and the second data pair is the total strain at the yield stress. The former writes TABLES1 with TYPE=2 and the latter writes TABLES1 with TYPE=1. † For a Stress/Strain Curve input this is not allowed as the stress/strain curve is not defined. An error will occur in MSC Nastran. For Hardening Rule and Perfectly Plastic, a TABLES1 entry is written defining the yield stress as a function of strain-rate starting from zero (0) strain-rate, i.e., the first data point needs to be (0,!0). ‡ For a Stress/Strain Curve input this is not allowed as the stress/strain curve is not defined. An error will occur in MSC Nastran. For Hardening Rule and Perfectly Plastic, a TABLEM1 entry is written defining the yield stress as a function of temperature. The lowest temperature value should be the reference temperature or zero (0) if not defined.

Main Index

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** For a Stress/Strain Curve input this is not allowed as the stress/strain curve is not defined. An error will occur in MSC Nastran. For Hardening Rule and Perfectly Plastic, a TABLES1 and a TABLEM1 entry are written defining the yield stress as a function of strain-rate starting from zero (0) strain-rate at the reference temperature (or zero (0) if not defined) from the first row of data, and yield stress as a function of temperature from the first column of data. In order for the strain-rate data to be written, the Strain Rate Method must be set to Piecewise Linear. Only these two rows of data are written. All other data in the table, except the first row and column, may be set to zero (0.0) and are ignored, e.g.,

er-1:

er-2:

er-3:

e4-4:

0.0

0.1

0.2

0.3

T-1:

0.0

10000

11000

12000

13000

T-2:

50.0

10500

0.0

0.0

0.0

T-3:

100 0

10600

00

00

00

†† Only allowable for Stress/Strain Curve data. A TABLEST referencing various TABLES1 entries is written. Each row of data defines a separate TABLES1 at each specified temperature. The first column of data should be the yield stresses per temperature at zero true plastic strain for TABLES1 TYPE=2, otherwise the first column should be all zeros (0.0) and the second column should be the yield stress per temperature for true total strain, e.g.,

Main Index

e-1:

e-2:

e-3:

e-4:

e-5:

0.0

0.001

0.01

0.1

1.0

T-1:

0.0

10000

9000

8000

7000

6000

T-2:

50.0

10500

9500

8500

7500

6500

T-3:

100 0

10600

9600

8600

7600

6600

Chapter 2: Building A Model Materials

‡‡ Only allowable for Stress/Strain Curve data. Two TABLES1 entries are written. The rows define either true plastic strain or true total strain. The columns define the strain-rate. In order for the strain-rate data to be written, the Strain Rate Method must be set to Piecewise Linear. Only the first row and column of data are written. All other data in the table, except the first row and column, may be set to zero (0.0) and are ignored. For the first row, a TABLES1 entry is written defining the yield stress as a function of strain-rate starting from zero (0) strain-rate, i.e., the first data point needs to be (0,!0). Because of this, only TYPE=2 is supported for the TABLES1 defining stress versus extracted from the first column, this data must be yield stress versus true plastic strain, i.e., the first data pair is (0,!0) defining the yield stress at zero plastic strain, e.g.,

Main Index

er-1:

er-2:

er-3:

e4-4:

0.0

0.1

0.2

0.3

e-1:

0.0

10000

11000

12000

13000

e-2:

0.001

9000

0.0

0.0

0.0

e-3:

0.01

8000

0.0

0.0

0.0

e-4:

0.1

7000

0.0

0.0

0.0

e-5:

1.0

6000

0.0

0.0

0.0

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Materials

***Only allowable for Stress/Strain Curve data. This is a multi-layer field where the first layer defines yield stress versus temperature and strain. Data on the first layer is at zero (0.0) strain-rate and writes a TABLEST referencing various TABLES1 entries. Each row of data defines a separate TABLES1 at each specified temperature. The first column of data must be the yield stresses per temperature at zero true plastic strain for TABLES1 TYPE=2, e.g.,

er = 0.0

e-1:

e-2:

e-3:

e-4:

e-5:

0.0

0.001

0.01

0.1

1.0

T-1:

0.0

10000

9000

8000

7000

6000

T-2:

50.0

10500

9500

8500

7500

6500

T-3: 100 0 10600 9600 8600 7600 6600 The remaining layers define the yield stress at the other strain-rates and the only data point necessary to define is the first row/column entry. All other data points can be set to zero and are ignore, e.g.,

er = 0.1

e-2:

e-3:

e-4:

e-5:

0.0

0.001

0.01

0.1

1.0

T-1:

0.0

11000

0.0

0.0

0.0

0.0

T-2:

50.0

0.0

0.0

0.0

0.0

0.0

T-3:

100 0

00

00

00

00

00

e-1:

e-2:

e-3:

e-4:

e-5:

0.0

0.001

0.01

0.1

1.0

er = 0.2 T-1:

0.0

12000

0.0

0.0

0.0

0.0

T-2:

50.0

0.0

0.0

0.0

0.0

0.0

T-3:

100 0

00

00

00

00

00

e-1:

e-2:

e-3:

e-4:

e-5:

0.0

0.001

0.01

0.1

1.0

er = 0.3

Main Index

e-1:

T-1:

0.0

13000

0.0

0.0

0.0

0.0

T-2:

50.0

0.0

0.0

0.0

0.0

0.0

T-3:

100 0

00

00

00

00

00

Chapter 2: Building A Model Materials

Viscoplastic The Input Properties form displays the following for Viscoplastic material model. Use this form to define viscoplastic or creep behavior of a material. Table 2-19 Viscoplastic Material Properties Property Coefficient

Bulk Data (field) MATVP (A)

Description Enter the coefficient A. Its value should be other than 1.0 and 0.0.

Exponent of Stress MATVP (M)

Exponent m for stress.

Exponent of Creep MATVP (N) Strain

Exponent n for strain.

Exponent of Temperature

Exponent p for temperature.

MATVP (P)

Exponent of Time MATVP (Q)

Exponent q for time.

Creep Analysis Using NLSTEP

Creep is an important factor in elevated-temperature stress analysis. In SOL 400, creep is represented by a Maxwell model. Creep is a time-dependent, inelastic behavior, and can occur at any stress level (that is, either below or above the yield stress of a material). For Creep analysis using NLSTEP, the creep time behavior is specified using the CREEP option of the NLSTEP bulk data entry. Creep is used in the current load case if the CREEP value of NLSTEP is set to 1. Adaptive load stepping based upon creep can be flagged through NLSTEP CRITTID parameter. The NLSTEP method of creep characterization is available for the enhanced nonlinear elements only. MATVP is the only form of creep data material supported by SOL 400 when advanced elements are used. This creep capability is available for isotropic, orthotropic, and anisotropic materials, which can be coupled with plasticity using the MATEP entry. Coupling with plasticity is allowed only for selected plasticity models, which include von Mises, Hill's anisotropy (creep stays isotropic), and Mohr-Coulomb models. The creep formulation explicit / implicit is specified though NLMOPTS bulk data entry with CREEP keyword options. Current support for creep analysis using NLSTEP includes: 

MATVP Viscoplastic or Creep material coefficients format for isotropic, orthotropic, and anisotropic models



MATEP elasto-plastic material for isotropic, orthotropic, and anisotropic models using ImpCreep and VParam keywords



Analysis solution parameters NLMOPTS CREEP keyword options – written automatically if creep is present and activated



Analysis load step static parameters for NLSTEP CREEP option

Thus the following combination of creep analysis using NLSTEP are supported:

Main Index

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

Implicit or explicit creep using MATVP only



Explicit Creep using MATVP coupled with plasticity using MATEP and Yield criteria von Mises/Hill/Mohr-Coulomb models



Implicit Creep using MATVP coupled with plasticity using MATEP and Yield criteria Implicit creep for von Mises tensile yield stress (ImpCreep keyword)

Note:

In order to activate a creep analysis, not only do the material properties have to be defined for the analysis, but the solution parameters and analysis load step settings must be activated also. See Solution Parameters, 298 and Load Step Parameters, 320 for Static Analysis.

Failure 1, Failure 2, Failure 31 The Input Properties form displays the following for failure material models. Up to three failure constitutive models can be defined for any one material. Failure 1 must exist in order for Failure 2 and Failure 3 to be recognized and translated into the proper bulk data MATF entries. Temperature dependent properties as defined by material fields are translated onto the MATTF entry and defined using the Fields Application (Ch. 6) in the Patran Reference Manual. Table 2-20 Failure Material Options Property Failure Criterion

Bulk Data (field) MATF (“CRI”, CRITERION)

Progressive Failure MATF (ITYPE) Options*

Description Valid failure criterion are: Maximum Stress, Maximum Strain, Hill, Hoffman, Tsai-Wu, Hashin, Puck, HashinTape, Hashin-Fabric. The properties available are dependent on the selected criterion. Progressive failure options are None, Gradual or Immediate. Only failure indices are computed when no progressive failure is specified.

* Note that only Failure 1 allows for definition of progressive failure. Failure 2 and Failure 3 models take on whatever progressive failure is defined in Failure 1. Progressive failure is not available for Anisotropic materials.

1

Main Index

Failure criterion is available for all Isotropic, Orthotropic, and Anisotropic materials.

Chapter 2: Building A Model Materials

Table 2-21 Failure Material Properties Property Tension Stress Limit X / Y /Z Tension Strain Limit X / Y / Z

Bulk Data (field)

Description

MATF (“CRI”, V1-V9) or (“CRI”, W1-W9) MATTF

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

Interactive Strength XY / YZ / ZX

MATF (“CRI”, V10-V12) MATTF

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

Max Fiber / Matrix Tension Max Fiber / Matrix Compression

MATF (“CRI”, V1-V4) MATTF

Definable stress limits for Hashin, Puck, Hashin-Tape, and HashinFabric criteria.

Layer Shear Strength Transverse Shear Strength YZ / ZX

MATF (“CRI”, V10-V12) MATTF

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

Slope P12C / P12T / P23C / P23T of Fracture Envelope

MATF (“CRI”, W1-W4) MATTF

Slopes of the failure envelope used in Puck failure criterion.

Residual Stiffness Factor Matrix Compression Factor Shear Stiffness Factor E33 Fiber Failure Factor Shear Fiber Failure Factor

MATF (“PF”, A1-A5)

Reduction fractions or factors. Values can be between 0.0 and 1.0. Used only for Gradual or Immediate progressive failure modes. Only applicable properties are visible for the selected failure criterion.

Compression Stress Limit X / Y / Z Compression Strain Limit X / Y / Z Shear Stress Limit XY / YZ / ZX Shear Strain Limit XY / YZ / ZX

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

Main Index

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Hyperelastic1 The Input Properties form displays the following for hyperelastic properties. Use this form to define the data describing hyperelastic behavior of a material, generally used for rubber type materials. There are two basic types of data, Test Data and Coefficients, that can be defined. Table 2-22 Hyperelastic Material Options (Test Data*) Property

Bulk Data (field)

Description

Tension/Compres sion TAB1

MATHE (MODEL=MOONEY,TAB1) TABLES1

Test data for simple tension-compression used in the estimation of the Cij material constants. Values must be stretch ratios (l/lo) vs. engineering stress F/(Ao-lo). lo is the initial length and Ao is the initial cross section.

Equibiaxial Tension TAB2

MATHE (MODEL=MOONEY,TAB2) TABLES1

Test data for equibaxial tension data used in the estimation of the Cij material constants. Values must be stretch ratios (l/lo) vs. engineering stress F/(Ao-lo). lo is the initial length and Ao is the initial cross section.

Simple Shear Data MATHE TAB3 (MODEL=MOONEY,TAB3) TABLES1

Test data for simple shear data used in the estimation of the Cij material constants. Values must be shear strain vs. engineering shear stress.

Pure Shear Data TAB4

MATHE (MODEL=MOONEY,TAB4) TABLES1

Test data for pure shear data used in the estimation of the Cij material constants. Values must be stretch ratios (l/lo) vs. nominal stress F/(Ao-lo). lo is the initial length and Ao is the initial cross section, both in the 1-direction.

Pure Volume Compression TABD

MATHE (MODEL=MOONEY,TABD) TABLES1

Test data for pure volumetric compression used in the estimation of the Di material constants. Values must be volume ratio J=(l/lo)3 vs. pressure , assumed positive in compression. l/lo is the stretch ratio in all three directions.

* All data must be provided as a reference to a strain dependent field defining the test data created in the Fields Application (Ch. 6) in the Patran Reference Manual. The Experimental Data Fitting (Ch. 11) in the Patran Reference Manual utility under the Tools menu can be used to determine the coefficients and enter them manually with the Coefficients data type if desired.

1

Main Index

Hyperelastic materials are applicable to most 2D solid plane strain/stress/axisymmetric, shell type, 3D solid elements, including gaskets.

Chapter 2: Building A Model Materials

Table 2-23 Hyperelastic Material Options (Coefficients) Property

Bulk Data (field)

Description General Properties

Bulk Modulus

MATHE (K) MATTHE

Bulk modulus. Set to -1 if any Di coefficients are provided. May be temperature dependent.

Density

MATHE (RHO) MATTHE

Mass density. May be temperature dependent.

Thermal Expansion Coefficient

MATHE (TEXP) MATTHE

Coefficient of volumetric thermal expansion. May be temperature dependent.

Reference Temperature

MATHE (TREF)

Defines the reference temperature for the thermal expansion coefficient. Other material properties are evaluated at this reference temperature when temperature dependencies are detected.

Structural Damping Coefficient

MATHE (GE) MATTHE

Structural damping element coefficient. May be temperature dependent. Mooney-Rivlin

Main Index

Coefficeints Cij

MATHE (MODEL=MOONEY, Cij) MATTHE

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 hyperelastic material models, including Neo-Hookean (C10 only), Mooney-Rivlin (C10 & C01), and Full Third Order Invariant (all coefficients). The Order of the Polynomical determines the number of coefficients required as input.

Coefficients Di

MATHE (MODEL=MOONEY, Di) MATTHE

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

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Table 2-23 Hyperelastic Material Options (Coefficients) (continued) Property

Bulk Data (field)

Description Ogden

Modulus i

MATHE (MODEL=OGDEN, MUi)

μ k in the Ogden equation. The number of moduli required as input is dependent on the Order of the Polynomial.

Exponent i

MATHE (MODEL=OGDEN, ALPHAi)

α k in the Ogden equation. The number of exponents required as input is dependent on the Order of the Polynomial.

Coefficients Di

MATHE (MODEL=OGDEN, Di) MATTHE

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

Foam

Main Index

Modulus i

MATHE (MODEL=FOAM, MUi)

u n in the Foam equation. The number of moduli required as input is dependent on the Order of the Polynomial.

Deviatoric Exponent i

MATHE (MODEL=FOAM, ALPHAi)

α n in the Foam equation. The number of exponents required as input is dependent on the Order of the Polynomial.

Volumetric Exponent i

MATHE (MODEL=FOAM, BETAi)

β n in the Foam equation. The number of exponents required as input is dependent on the Order of the Polynomial.

Coefficients Di

MATHE (MODEL=FOAM, Di) MATTHE

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

Chapter 2: Building A Model Materials

Table 2-23 Hyperelastic Material Options (Coefficients) (continued) Property

Bulk Data (field)

Description Arruyda-Boyce

NKT

MATHE (MODEL=ABOYCE, Chain density times Boltzmann constant times NKT) temperature. May vary with temperature via a MATTHE defined material field.

Chain Length

MATHE (MODEL=ABOYCE, Average chemical chain cross length. May vary N/E) with temperature via a defined material field. MATTHE

Coefficients Di

MATHE (MODEL=ABOYCE, Material constants related to volumetric Di) deformation. The Order of the Polynomial MATTHE determines the number of coefficients required as input. May be temperature dependent. Gent

Tensile Modulus

MATHE (MODEL=GENT, N/E) MATTHE

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

Maximum 1st Invariant

MATHE (MODEL=GENT, IM) MATTHE

Defines I *1 = I 1 – 3 . May vary with temperature via a defined material field.

Coefficients Di

MATHE (MODEL=GENT, Di) MATTHE

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

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 traction-displacement curve is called the cohesive energy (which is also called the critical energy release rate). The names of the three standard

Main Index

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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 the following characteristics: Exponential model: entirely defined by an exponential function; the necessary material properties are the cohesive energy (Gc) and the critical opening displacement (vc). Bilinear 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

Main Index

Chapter 2: Building A Model Materials

Note that for the linear model one still has to select the critical opening displacement and for the linearexponential model the decay factor. They can be used to influence the reversible response. Table 2-24 Cohesive Material Options Property Constitutive Model Stiffness Matrix

Bulk Data (field) MCOHE (MODEL)

Description Constitutive Models for Cohesive Material. Options are: Bilinear, Exponential and LinearExponential. Only Secant is currently valid for MSC Nastran. 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

Options are: No and Yes.

Reference Rate

Options are: None, Auto, and User Defined.

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.

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

Main Index

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Table 2-24 Cohesive Material Options Property

Bulk Data (field)

Fully Damages Elements

Description 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.

Cohesive Energy

MCOHE (COHE)

This can also refer a Temperature/Strain/StrainRate field.

Critical Opening Displacement

MCOHE (CRTOD)

Enter a opening displacement values

Maximum Opening Displacement

MCOHE (MAXOD)

Used for "Bilinear" model only

Shear-Normal Stress Ratio

MCOHE (SNSR)

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

Compression Stiffening Factor

MCOHE (SFC)

Stiffening factor in compression

Viscous Energy Dissipation

MCOHE (VED)

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

Reference Rate

MCOHE (RRRD)

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

MCOHE (EXP)

Used for Linear-Exponential model only

Shear-Normal Energy Ratio

MCOHE (SNER)

This is used for Shear-Normal Energy Ratio analysis.

Laminate The Composite Laminate form provides a way of defining composite entries (PCOMP or PCOMPG1) in the MSC Nastran input file for shell elements. PLCOMP or PCOMPLS are written for 2D and 3D solid element., respectively.

Main Index

Chapter 2: Building A Model Element Properties

When the Laminated Composite option is used to create a material and this material is then referenced in a Revised or Standard formulated Laminate plate (shell) element property region, a PCOMP or PCOMPG entry is created. However, if this material is referenced by a different type of element property region, for example, Revised or Standard formulated Homogeneous plate (shell) element, 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 formulated Laminate plate (shell) element property region. Refer to Composite Materials Construction (p. 108) in the Patran Reference Manual for the actual instruction on the usage of this form. This subordinate form appears when the Input Properties... button is selected on the Materials application. Composite is the selected Object, and Laminate is the selected Method. Different Stacking Sequence Options are available. 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 to be given as a percentage of the total lay-up thickness. This is the preferred method when applying the composite material to 3Dsolid (CHEXA) elements or 2D solid element (axisymmetric, plane strain)..

Element Properties To define element properties and associate materials to the finite elements, first ensure that the Analysis Code and Type are set properly to Implicit Nonlinear. See Setting the Analysis Code and Type, 2.

1

Main Index

A PCOMPG is written as opposed to a PCOMP by supplying the global ply numbers and turning ON the Write Global Ply IDs toggle on the Translation Parameters form. See Translation Parameters, 291.

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The element properties shown in the following table are available for the Implicit Nonlinear preference.

The Elem Property Actions application is accessed by clicking on the Properties tab or switch on the main Patran form. Properties are categorized by geometric dimensionality (as opposed to the analysis dimensionality) of the elements to which they are associated as shown below.

Main Index

Chapter 2: Building A Model Element Properties

Table 2-25 Element Property Options Dimension 0D

Type 

Mass

page 91

1D

Option 1 

Coupled page 91



Grounded page 92



Lumped page 93



Grounded Scalar Spring page 94



Grounded Scalar Damper page 96



Grounded Conductor page 97



Grounded Capacitor page 98



Grounded Bush page 99



Beam



General Section

page 101



Rod page 118



Spring page 120



Damper



Main Index

Gap



1D Mass page 125



Conductor page 126



Capacitor page 127



Bush

Option 2



Standard page 101



Linear/Cubic Closed Section page 107



Linear-Shear (Bar) page 107



Lumped Section page 108



Tapered Section page 110



General Section (CBEAM)



Standard page 113



Linear/Cubic Closed Section page 116



Linear/Cubic Open Section page 116



Linear-Shear (Beam) page 117



Scalar page 121



Viscous page 122



Adaptive page 123



Non-Adaptive page 123



Scalar page 128



2D Linear/nonlinear page 131



Spot Weld Connector page 132



Fastener Connector page 133

Option 4

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Table 2-25 Element Property Options (continued) Dimension 2D

Type 

Shell

Option 1 

Thin

Option 2 

Homogeneous

page 136

Option 4 

Standard page 136



Revised page 139



Linear Discrete Kirchhoff page 139











Bending Panel 2D-Solid

Thick



Standard page 157



Revised page 159



Plane Strain

Laminate Equivalent Section

Plane Stress page 169



Axisymmetric



Main Index

Membrane Shear Panel page 185



Standard page 182



Revised page 184



Revised page 146



Standard page 148



Revised page 150

Standard page 152



Reduced Integration page 154



Homogeneous



Standard page 161



Reduced page 163



Revised page 164



Incompressible page 164



Interface page 165



Laminated Composite page 166



Gasket page 167



Standard page 169



Reduced page 171



Interface page 172



Homogeneous

page 173



Standard page 143



page 161







Standard page 173



Reduced page 175



Twist page 176



Incompressible page 177



Interface page 178



Laminated Composite page 179



Gasket page 180

Chapter 2: Building A Model Element Properties

Table 2-25 Element Property Options (continued) Dimension 3D

Type 

Solid

Option 1 

Homogeneous

page 188





Main Index

Body Pair

Laminate



Gasket page 199



Interface page 201



Geometric page 201



Physical page 204

Option 2 

Standard page 188



Reduced page 190



Solid Shell page 192



Incompressible page 194



Standard page 195



Solid Shell page 197

Option 4

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Table 2-26 Nonlinear Property Formulations vs. MSC Nastran Property Entries Automatic No Elastoplastic or Contact

Formulation

With Elastoplastic and/or Contact

Large Strain

Small Strain

Beam Standard (CBAR) PBAR/L page 101

Standard (CBEAM) PBEAM/L page 113

PBAR/L PBARN1 (C2,BAR,LC)

PBAR/L PBARN1 (C2,BAR,LC)

PBAR/PL

PBEAM/L PBEMN1 (C2,BEAM,LC)

PBEAM/L PBEMN1 (C2,BEAM,LC)

PBEAM/L

PBEAM/L PBEMN1 (C2,BEAM,LC)

PBEAM/L PBEMN1 (C2,BEAM,LC)

PBEAM/L

PSHELL PSHLN1 (C3, DCNT,L) (C4,DCNT,L) (C6,MB,Q) (C8,DCT,QRI)

PSHELL PSHLN1 (C3, DCNT,L) (C4,DCNT,L) (C6,MB,Q) (C8,DCT,QRI)

PSHELL

Linear Cubic/Closed (CBAR) PBAR/L page 107 PBARN1 (C2,BAR,LCC) Linear Cubic/Closed (CBEAM) PBEAM/L page 116 PBEMN1 (C2,BEAM,LCC) Linear Cubic/Open (CBEAM) PBEAM/L page 116 PBEMN1 (C2,BEAM,LCO) Linear Shear (CBAR) PBAR/PL page 107 PBARN1 (C2,BAR,LS) Linear Shear (CBEAM) PBEAM/PL page 117 PBEMN1 (C2,BEAM,LS) Lumped Section PBCOMP page 108

Tapered Section PBEAM/L page 110

Thin Shell Standard PSHELL page 136

Revised PSHELL page 139

Linear Discrete Kirchhoff PSHELL page 141 PSHLN1 (C3, DCNT,LDK / C4,DCNT,LDK) Laminate, Standard PCOMP/G page 143

Main Index

PCOMP/G PSHLN1

PCOMP/G PSHLN1

PCOMP/G

Chapter 2: Building A Model Element Properties

Table 2-26 Nonlinear Property Formulations vs. MSC Nastran Property Entries Automatic No Elastoplastic or Contact

Formulation

With Elastoplastic and/or Contact

Large Strain

Small Strain

Laminate, Revised PCOMP or PCOMG page 146

Equivalent Section, Standard PSHELL page 148

PSHELL PSHLN1 (C3, DCNT,L) (C4,DCNT,L) (C6,MB,Q) (C8,DCT,QRI)

PSHELL PSHLN1 (C3, DCNT,L) (C4,DCNT,L) (C6,MB,Q) (C8,DCT,QRI)

PSHELL

SHELL PSHLN1 (C3,MB,L) (C4,MB,L) (C6,MB,Q) (C8,MB,Q)

SHELL PSHLN1 (C3,MB,L) (C4,MB,L) (C6,MB,Q) (C8,MB,Q)

PSHELL

PSHEAR PSHEARN

PSHEAR PSHEARN

PSHEAR

Equivalent Section, Revised PSHELL page 150

Thick Shell Standard PSHELL page 152 PSHLN1 (C4,DCT,L) Reduced PSHELL page 154 PSHLN1 (C4,DCT,LRIH / C8,DCT,QRI) Bending Panel Standard PSHELL page 157

Revised PSHELL page 159

Membrane Standard PSHELL page 182

Revised PSHELL page 184

Shear Panel page 185

Main Index

PSHEAR

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Table 2-26 Nonlinear Property Formulations vs. MSC Nastran Property Entries Automatic No Elastoplastic or Contact

Formulation

With Elastoplastic and/or Contact

Large Strain

Small Strain

Plane Strain: Standard PSHELL page 161 MID2=-1

PLPLANE PSHLN2 (C3,PLSTRN,L) (C4,PLSTRN,L) (C6,PLSTRN,Q) (C8,PLSTRN,Q)

PLPLANE PSHLN2 (C3,PLSTRN,L) (C4,PLSTRN,L) (C6,PLSTRN,Q) (C8,PLSTRN,Q)

PLPLANE

Reduced Integration PLPLANE page 163 PSHLN2 (C4,PLSTRN,LRIH / C8,PLSTRN,QRI) Revised PSHELL MID2=-1 page 164

Incompressible PLPLANE page 164 PSHLN2 (C3,IPS,L) Interface PCOHE page 165

Laminate PLCOMP (C4,COMPS,L / C8,COMPS,Q) page 166

Gasket PLPANE page 167

Plane Stress: Standard PLPLANE page 169

PLPLANE PSHLN2 (C4,PSTRS,L) (C6,PSTRS,Q) (C8,PSTRS,Q)

PLPLANE PSHLN2 (C4,PSTRS,L) (C6,PSTRS,Q) (C8,PSTRS,Q)

PLPLANE

Reduced PLPLANE (C4,PSTRS,LRIH / C8,PSTRS,QRI) page 171

Interface PCOHE page 172

Axisymmetric Standard PLPLANE page 173

Main Index

PLPLANE PSHLN2 (C3,AXSOLID,L) (C4,AXSOLID,L) (C6,AXSOLID,Q) (C8,AXSOLID,Q)

PLPLANE PSHLN2 (C3,AXSOLID,L) (C4,AXSOLID,L) (C6,AXSOLID,Q) (C8,AXSOLID,Q)

PLPLANE

Chapter 2: Building A Model Element Properties

Table 2-26 Nonlinear Property Formulations vs. MSC Nastran Property Entries Automatic No Elastoplastic or Contact

Formulation

With Elastoplastic and/or Contact

Large Strain

Small Strain

Reduced PLPLANE (C4,AXSOLID,LRIH / C8,AXSOLID,QRI) page 175

Twist PLPLANE (C4,AXSOLID,LT/ C8,AXSOLID,QT) page 176

Incompressible PLPLANE (C3,IAX,L) page 177

Interface PCOHE page 178

Laminate PLCOMP (C4,AXCOMP,L / C8,AXCOMP,Q) page 179

Gasket PLPANE page 180 PSHLN2 (C4,AXCOMP,L)

Solid Standard PSOLID page 188

PSOLID PSLDN1 (C4,SOLID,L) (C6,SOLID,L) (C8,SOLID,L (C10,SOLID,Q) (C15,SOLID,Q) (C20,SOLID,Q)

PSOLID PSLDN1 (C4,SOLID,L) (C6,SOLID,L) (C8,SOLID,L (C10,SOLID,Q) (C15,SOLID,Q) (C20,SOLID,Q)

PSOLID

Reduced PSOLID page 190 PSLDN1 (C8,SOLID,LRIH / C10,SOLID,LRIH / C20,SOLID,QRI) Solid Shell PSOLID page 192 PSLDN1 (C8, SLCOMP,L) Incompressible PSOLID page 194 PSLDN1 (C4,ISOL,L) Laminate - Standard PCOMPLS (C8,SLCOMP,L / C20,SLCOMP,Q) page 195

Laminate - Solid Shell PCOMPLS (C8,SLCOMP,ASTN) page 197

Gasket PSOLID (with MATG) page 199 PSLDN1 (C8,SLCOMP,L)

Interface PCOHE page 201

Main Index

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Element Properties Form This form appears when Element Properties application is selected on the main menu. As a brief explanation of how this form works, first set the options defining the property Object (0D, 1D, 2D, 3D) and the Type of property, enter the Property Set Name, and set the Options as necessary on the application itself. Define the elements or geometry to which the properties are to be associated using the Select Application Region... button and subordinate form. Input the property values using the Input Properties... button and subsequent form. For a full description, see Element Properties Forms (p. 63) in the Patran Reference Manual. This chapter describes only the different element properties available for each Object, Type, and Option.

Main Index

Chapter 2: Building A Model Element Properties

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

This creates the following MSC Nastran element and associated materials: Table 2-27 Coupled Point Mass (CONM1) Element CONM1

Allowable Material Not Applicable

Material Entry None

The allowable properties define a 6x6 symmetric mass matrix at a geometric point of the structural model. Table 2-28 Coupled Point Mass Properties (CONM1*) Property

Bulk Data (field)

Description

Mass Orientation CONM1 (CID) 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 CONM1 (Mii) 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.

* The G field of the CONM1 is the node ID to which this point element is associated.

Main Index

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0D - Grounded Scalar Mass (CMASS1/CMASS21) 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

This creates the following MSC Nastran element and associated materials: Table 2-29 Grounded Scalar Mass (CMASS1/CMASS2) Element

Allowable Material

Material Entry

CMASS1/PMASS

Not Applicable

None

CMASS2

Not Applicable

None

The allowable properties are described below. This defines a scalar mass element of the structural model. Only one node is used in this method. The other node is defined to be grounded. Table 2-30 Grounded Scalar Mass Properties (CMASS1/CMASS2*) Property

Bulk Data (field)

Description

Mass

CMASS2 (M) PMASS (M)

Defines the translation mass or rotational inertia value to be applied. This is the M field on the CMASS2 or 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

CMASS1 (C1) CMASS2 (C1)

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.

* The G1 field of the CMASS1 or CMASS2 is the node ID to which this point element is associated.

1

Main Index

To control whether a CMASS1 entry, which uses a separate property entry, or a CMASS2, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

Chapter 2: Building A Model Element Properties

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

This creates the following MSC Nastran element and associated materials: Table 2-31 Lumped Point Mass (CONM2) Element CONM2

Main Index

Allowable Material Not Applicable

Material Entry None

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The allowable properties are described below. Table 2-32 Lumped Point Mass Properties (CONM2*) Property Mass

Bulk Data (field) CONM2 (M)

Description 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 CONM2 (CID) CID/GG CONM2 (X1-3)

If Value Type is CID, 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 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 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 and the vector is written to the X1, X2, X3 fields. This property is optional.

Mass Offset

CONM2 (X1-3)

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. This is ignored if Value Type is Vector for the Mass Orientation.

Inertia i,j

CONM2 (Iij)

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.

* The G field of the CONM2 is the node ID to which this point element is associated.

0D - Grounded Scalar Spring (CELAS1/CELAS21) This describes the Input Properties available from the Element Properties form when the following options are chosen.

Main Index

Action

Dimension

Type

Create Modify

0D

Grounded Spring

Option(s)

Topologies Point/1

Chapter 2: Building A Model Element Properties

This creates the following MSC Nastran element and associated materials: Table 2-33 Grounded Scalar Spring (CELAS1/CELAS2*) Element

Allowable Material

Material Entry

CELAS1/PELAS

Not Applicable

None

CELAS2

Not Applicable

None

* Note that these elements are NOT written to the input file if only thermal Load Steps are defined for the analysis. There must be at least one structural Load Step defined. The allowable properties are described below. 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. Table 2-34 Grounded Scalar Spring Properties (CELAS1/CELAS2*) Property

Bulk Data (field)

Description

Spring Constant

PELAS (K) CELAS2 (K)

Defines the coefficient to be used for this spring. This is the K field on the CELAS2 or PELAS entry. This can either be a real value or a reference to an existing field definition. This property is required.

Damping Coefficient

PELAS (GE) CELAS2 (GE)

Defines what damping is to be included. This is the GE field on the CELAS2 or PELAS entry. This property can either be a real value or a reference to an existing field definition. This property is optional.

Stress Coefficient

PELAS (S) CELAS2 (S)

Defines the relationship between the spring deflection and the stresses within the spring. This property is the S field on the CELAS2 or 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

CELAS1 (C1) CELAS2 (C1)

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 CELAS1or CELAS2 entry. This property is required.

* The G1 field of the CELAS1/CELAS2 is the node ID to which this point element is associated.

1

Main Index

To control whether a CELAS1 entry, which uses a separate property entry, or a CELAS2, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

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0D - Grounded Scalar Damper (CDAMP1/CDAMP21) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Create Modify

0D

Grounded Damper

Topologies Point/1

This creates the following MSC Nastran element and associated materials: Table 2-35 Grounded Scalar Damper (CDAMP1/CDAMP2*) Element

Allowable Material

Material Entry

CDAMP1/PDAMP

Not Applicable

None

CDAMP2

Not Applicable

None

* Note that these elements are NOT written to the input file if only thermal Load Steps are defined for the analysis. There must be at least one structural Load Step defined. The allowable properties are described below. 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. Table 2-36 Grounded Scalar Damper Properties (CDAMP1/CDAMP2*) Property

Bulk Data (field)

Description

Damping Coefficient

PDAMP (B) CDAMP2 (B)

Defines the force per unit velocity value to be used. This property is the B field on the CDAMP2 or 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

CDAMP1 (C1) CDAMP2 (C1)

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 or CDAMP2 entry. This property is required.

* The G1 field of the CDAMP1/CDAMP2 is the node ID to which this point element is associated.

1

Main Index

To control whether a CDAMP1 entry, which uses a separate property entry, or a CDAMP2, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

Chapter 2: Building A Model Element Properties

0D - Grounded Conductor (CELAS1/CELAS21) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Option(s)

Create Modify

0D

Grounded Conductor

Topologies Point/1

This creates the following MSC Nastran element and associated materials: Table 2-37 Grounded Conductor (CELAS1/CELAS2*) Element

Allowable Material

Material Entry

CELAS1/PELAS

Not Applicable

None

CELAS2

Not Applicable

None

* Note that these elements are NOT written to the input file if only structural Load Steps are defined for the analysis. There must be at least one thermal Load Step defined. The allowable properties are described below. This defines a scalar conductor element of the thermal model. Only one node is used in this method. The other node is defined to be a heat sink. Table 2-38 Grounded Conductor Properties (CELAS1/CELAS2*) Property Thermal Conductance

Bulk Data (field) PELAS (K) CELAS2 (K)

Description This defines a simple conductance link between a node and a zero temperature heat sink. This value can either be real or a reference to an existing field definition.

* The G1 field of the CELAS1/CELAS2 is the node ID to which this point element is associated.

1

Main Index

To control whether a CELAS1 entry, which uses a separate property entry, or a CELAS2, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

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0D - Grounded Capacitor (CDAMP1/CDAMP21) 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

0D

Capacitor

Grounded

Point/1

This creates the following MSC Nastran element and associated materials: Table 2-39 Grounded Capacitor (CDAMP1/CDAMP2*) Element

Allowable Material

Material Entry

CDAMP1/PDAMP

Not Applicable

None

CDAMP2

Not Applicable

None

* Note that these elements are NOT written to the input file if only structural Load Steps are defined for the analysis. There must be at least one thermal Load Step defined. The allowable properties are described below. This defines a scalar conductor element of the thermal model. Only one node is used in this method. The other node is defined to be a heat sink. Table 2-40 Grounded Capacitor Properties (CELAS1/CELAS2*) Property Thermal Capacitance

Bulk Data (field) PDAMP (B) CDAMP2 (B)

Description This defines a simple thermal capacitance link between a node and a zero temperature heat sink. This value can either be real or a reference to an existing field definition.

* The G1 field of the CDAMP1/CDAMP2 is the node ID to which this point element is associated.

1

Main Index

To control whether a CDAMP1 entry, which uses a separate property entry, or a CDAMP2, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

Chapter 2: Building A Model Element Properties

0D - Grounded Bush (CBUSH) 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

0D

Bush

Grounded

Point/1

This creates the following MSC Nastran element and associated materials: Table 2-41 Grounded Bush (CBUSH) Element CBUSH/PBUSH

Allowable Material Not Applicable

Material Entry None

The allowable properties are described below. The element property sets are created with this option for defining a grounded scalar bush joint, which is a generalized spring-damper structural element. If frequency dependent or nonlinear force deflection properties are supplied, the PBUSHT entry is also written. Otherwise it is not written. Only one node is used in this method. Table 2-42 Grounded Bush Properties (CBUSH*) Property

Main Index

Bulk Data (field)

Description

Bush Orientation System

CBUSH (CID)

Spring Constant i

PBUSH (K1-K6) Defines the stiffness associated with a particular degree of freedom. This property is defined in terms of force per unit displacement and is a real value.

Stiff. Freq Depend i

PBUSHT (“K”) TABLED1

Stiff. Force/Disp i

PBUSHT(“KN”) Defines the nonlinear force/displacement curves for each TABLED1 degree of freedom of the spring-damper system and is to reference an existing field definition defining force vs. displacement. The field must use displacement as its variable.

Damping Coefficient i

PBUSH(B1-B6)

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.

Defines the stiffness associated with a particular degree of freedom in terms of force per unit displacement and is to reference an existing field definition for defining stiffness vs. frequency. The field must use frequency as its variable.

Defines the force per velocity damping value for each degree of freedom. This property is defined in terms of force per velocity and is a real value.

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Table 2-42 Grounded Bush Properties (CBUSH*) (continued) Property

Bulk Data (field)

Description

Damp. Freq Depend i

PBUSHT(“GE”) TABLED1

Defines the force per velocity damping value for each degree of freedom. This property is a reference to an existing field definition for defining damping vs. frequency. The field must use frequency as its variable.

Structural Damping

PBUSH (GE1)

Defines the non-dimensional structural damping coefficient (GE1). This property is a real value.

Struc. Damp Freq Depend

PBUSHT(“GE”) TABLED1

Defines the non-dimensional structural damping frequency tables. These properties are references to existing field definitions for defining damping vs. frequency. The fields must use frequency as their variables.

Stress Recovery Translation Stress Recovery Rotation

PBUSH (SA, ST)

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

Strain Recovery Translation Strain Recovery Rotation

PBUSH (EA, ET)

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

* The GA field of the CBUSH is the node ID to which this point element is associated.

Main Index

Chapter 2: Building A Model Element Properties

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

This creates the following MSC Nastran element and associated materials: Table 2-43 General Section Standard Formulation Beam (CBAR) Element

Allowable Material

Material Entry

CBAR/PBAR/ PBARN1 (INT2=LC)

Isotropic

MAT1/MAT4

CBAR/PBARL/ PBARN1 (INT2=LC)

Isotropic

MAT1/MAT4

Use this form to create CBAR elements with a PBAR property or PBARL dimensions. A CBARAO entry is generated if any Station Distances are specified. This defines a simple beam element in the structural model. For advanced nonlinear formulation, a PBARN1 entry is also written with BAR written to the BHE2 field and the LC option written to the INT2 field. Note:

Patran checks the element associativity to other elements sharing this property set and does not export user-defined pin unless the user includes an asterisk (*) in the string, in which case Patran exports 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 appear on the input properties form. Whether a PBAR or a PBARL property entry is written is dependent on the setting of the Section Name pull down. Properties writes a PBARM, and Dimensions writes a PBARL.

Main Index

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Main Index

Chapter 2: Building A Model Element Properties

Table 2-44 General Section Beam Properties (CBAR*) Property Section Name

Bulk Data (field) PBAR PBARL PBRSECT

Description Allows you to define a bar/beam section either by Dimensions (PBARL) or by Properties (PBAR). If Dimensions is chosen, the MSC Nastran’s built-in section library, PBARL, (for the standard Beam Library) or PBRSECT (for an Arbitrary section) is used to define the bar. If Properties is chosen, the standard bar/beam properties, PBAR is used to define the beam section. To use Dimensions, specify a beam section previously created using the beam library. To create a beam section, click on the Create Sections (ICL... Beam Library) icon. This application allows you to define beam properties by choosing a standard cross section type and define dimensions. Also accessible under the Tools pull down menu. See Beam Library (Ch. 11) in the Patran Reference Manual.

Material Name

PBAR (MID) PBARL (MID)

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 or PBARL entry. This property is required.

Bar Orientation

CBAR (G0) CBAR (X1-X3)

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 entry. This property is required. Vector – Specified using a vector (X1-X3) Node Id – Specified using an existing node in the beam XY plane (G0) 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. ).

Main Index

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Table 2-44 General Section Beam Properties (CBAR*) (continued) Property Bar Orientation (cont.)

Bulk Data (field) CBAR( OFFT)

Description Scroll the form over to specify from a pull down in which MSC Nastran coordinate system the bar orientation vector is to be written to the CBAR 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 entry. If Coord 0 is specified, a B is 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 entry.

Offset @ Node 1 Offset @ Node 2

CBAR (W1A-W3A, W1B-W3B)

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 entry. These properties are optional. Specified using a vector. The Reference Coordinate System controls how the vector input is interpreted in Patran. The presence of offsets writes the MDLPRM,OFFDEF,LROFF to the input deck.

Offset @ Node 1 Offset @ Node 2 (cont.)

CBAR (OFFT)

Scroll the form over to specify from a pull down in which MSC Nastran coordinate system the offset vectors are to be written to the CBAR entry and how the vector input is interpreted in Patran: Analysis - Displacement Coordinate Systems at GA and GB Element - Element Coordinate System If Analysis is specified, a G is written to the second or third position of the OFFT value on the CBAR entry. Within Patran, the vector is interpreted to be in either the Patran global or some other Patran user defined coordinate system (i.e. ). If Element is specified, an E is written to the second or third position of the OFFT value on the CBAR entry. Within Patran, the vector is interpreted to be in the Element coordinate system.The presence of offsets writes the MDLPRM,OFFDEF,LROFF to the input deck.

Main Index

Chapter 2: Building A Model Element Properties

Table 2-44 General Section Beam Properties (CBAR*) (continued) Property Pinned DOFs @ Node 1

Bulk Data (field) CBAR (PA, PB)

Pinned DOFs @ Node 2

Description 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 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.

Main Index

Area

PBAR (A)

Inertia i,j

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

Torsional Constant

PBAR (J)

Defines the torsional stiffness of the beam. This is the J field on the PBAR 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

PBAR (K1, K2)

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.

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

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Table 2-44 General Section Beam Properties (CBAR*) (continued) Property

Bulk Data (field)

Description

Nonstructural Mass

PBAR (NSM)

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 entry. This value can be either a real value or reference to an existing field definition. This property is 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

PBAR (C1, C2, D1, D2, E1, E2, F1, F2)

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.

[Contact Beam Radius]

BCBMRAD

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 input file. You must turn on beam-to-beam contact in the Contact Detection form for this parameter to be written. See Contact Detection, 305.

[Station Distances]

CBARAO

Write the auxiliary output points along the bar element axis. List is a real list entered as numbers between 0.0 and 1.0, e.g. 0.25, 0.5, 0.75, representing distances along the parametric direction of the bar.

[Section Integration]

PBARN1 (SECT)

Value is written to the SECT field of the PBARN1/PBEMN1 entry. A smeared cross section or a numerically integrated cross section can be defined.

Nonlinear Formulation

PBARN1

This optional property word can take on any of the three values Automatic, Large Strain, or Small Strain. Automatic is the default, if not specified. It 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 entry is written for this property set. Large Strain forces the PBARN1 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 Load Step.

* The GA/GB fields of the CBAR are the node IDs to which this element is associated.

Main Index

Chapter 2: Building A Model 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

This creates the following MSC Nastran element and associated materials: Table 2-45 General Section Linear/Cubic Closed Beam (CBAR) Element

Allowable Material

Material Entry

CBAR/PBAR/ PBARN1 (INT2=LCC)

Isotropic

MAT1/MAT4

CBAR/PBARL/ PBARN1 (INT2=LCC)

Isotropic

MAT1/MAT4

Use this form to create CBAR elements with a PBAR or PBARL property and associated PBARN1 to define nonlinear, large displacement, large strain behavior. A PBARN1 entry is written with BAR written to the BEH2 field and the LCC option written to the INT2 field. A CBARAO entry is 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, 101 for the generic properties needed for any bar definition. Whether a PBAR or a PBARL property entry is written is dependent on the setting of the Section Name pull down. Properties writes a PBARM, and Dimensions writes a PBARL.

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

Main Index

Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section

Linear-Shear

Bar 2

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This creates the following MSC Nastran element and associated materials: Table 2-46 General Section Linear-Shear Beam (CBAR) Element

Allowable Material

Material Entry

CBAR/PBAR/ PBARN1 (INT2=LS)

Isotropic

MAT1/MAT4

CBAR/PBARL/ PBARN1 (INT2=LS)

Isotropic

MAT1/MAT4

Use this form to create CBAR elements with a PBAR or PBARL property and associated PBARN1 to define nonlinear, large displacement, large strain behavior. A PBARN1 entry is written with BAR written to the BEH2 field and the LS option written to the INT2 field. A CBARAO entry is 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, 101 for the generic properties needed for any beam/bar definition. Whether a PBAR or a PBARL property entry is written is dependent on the setting of the Section Name pull down. Properties writes a PBARM, and Dimensions writes a PBARL.

1D - Beam - Lumped Section (CBEAM) 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

This creates the following MSC Nastran element and associated materials: Table 2-47 Lumped Section Beam (CBEAM) Element CBEAM/PBCOMP

Allowable Material Isotropic

Material Entry MAT1/MAT4

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, 101 for the generic properties needed for any beam definition, substituting CBEAM for CBAR. Properties specific to defining this beam behavior are listed here.

Main Index

Chapter 2: Building A Model Element Properties

Table 2-48 Lumped Section Beam Properties (CBEAM*) Property

Main Index

Bulk Data (field)

Description

Material Name

PBCOMP (A)

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

PBCOMP (A)

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

PBCOMP (NSM)

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

PBCOMP (K1, K2)

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.

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Table 2-48 Lumped Section Beam Properties (CBEAM*) (continued) Property

Bulk Data (field)

Description

Y of NSM Z of NSM

PBCOMP (M1, M2)

Defines the offset from the centroid of the cross section to the location of the non structural 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.

Symmetry Option

PBCOMP (SYMOPT)

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

PBCOMP (Yi, Zi)

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.

PBCOMP (Ci)

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.

Zs of Lumped Areas Area Factors

* The GA/GB fields of the CBEAM are the node IDs to which this element is associated.

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

Main Index

Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

Tapered Section

Standard Formulation

Bar/2

Chapter 2: Building A Model Element Properties

This creates the following MSC Nastran element and associated materials: Table 2-49 Tapered Section Standard Formulation Beam (CBEAM) Element

Allowable Material

Material Entry

CBEAM/PBEAM/ PBEMN1 (INT2=LC)

Isotropic

MAT1/MAT4

CBEAM/PBEAML/ PBEMN1 (INT2=LC)

Isotropic

MAT1/MAT4

Use this form to create CBEAM elements with a PBEAM or PBEAML property. This defines a beam element with varying cross sections. For advanced nonlinear formulation, a PBEMN1 entry is also written with BEAM written to the BEH2 field and the LC option written to the INT2 field. 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 data boxes 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 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, 113. Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 101 for the generic properties needed for any beam/bar definition. Simply substitute CBEAM for CBAR and PBEAM/PBEAML for PBAR/PBARL as appropriate. Properties specific to defining this beam behavior are listed here. Whether a PBEAM or a PBEAML property entry is written is dependent on the setting of the Section Name pull down. Properties writes a PBEAM, and Dimensions writes a PBEAML. A PBMSECT is written if an arbirary beam section is selected.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Element Properties

Table 2-50 Tapered Section Beam Properties (CBEAM*) Property

Bulk Data (field)

Description

Station Distances

PBEAM (X/XB) PBEAML (X/XB)

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

PBEAM (A)

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

PBEAM (I1, I2, I12)

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

PBEAM (J)

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.

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

PBEAM (C1, C2, D1, D2, E1, E2, F1, F2)

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

PBEAM (NSM) PBEAML (NSM)

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.

NSM Inertia @ Node 1

PBEAM (NSI)

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.

NSM Inertia @ Node 2

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Chapter 2: Building A Model Element Properties

Table 2-50 Tapered Section Beam Properties (CBEAM*) (continued) Property

Bulk Data (field)

Description

Shear Stiff, Y Shear Stiff, Z

PBEAM (K1, K2)

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

PBEAM (S1, S2)

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

PBEAM (CW)

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

PBEAM ( N1, N2 )

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.

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

PBEAM (M1, M2)

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.

Warp Coeff. @ Node 2

* The GA/GB fields of the CBEAM are the node IDs to which this element is associated.

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

Main Index

Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section (CBEAM)

Standard Formulation

Bar/2

113

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Element Properties

This creates the following MSC Nastran element and associated materials: Table 2-51 General Section Standard Formulation Beam (CBEAM) Element

Allowable Material

Material Entry

CBEAM/PBEAM/ PBEMN1 (INT2=LC)

Isotropic

MAT1/MAT4

CBEAM/PBEAML/ PBEMN1 (INT2=LC)

Isotropic

MAT1/MAT4

Use this form to create CBEAM elements with a PBEAM or PBEAML property. This defines a beam element with varying cross sections. For advanced nonlinear formulation, a PBEMN1 entry is also written with BEAM written to the BEH2 field and the LC option written to the INT2 field. 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. See 1D - Beam - Tapered Section (CBEAM) - Standard Formulation, 110. Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 101 for the generic properties needed for any beam/bar definition. Simply substitute CBEAM for CBAR and PBEAM/PBEAML for PBAR/PBARL as appropriate. Also see 1D - Beam - Tapered Section (CBEAM) - Standard Formulation, 110 for a description of defining tapered beam properties. Properties specific to defining this beam behavior are listed here. Table 2-52 General Section Beam Properties (CBEAM*) Property Warping Option

Bulk Data (field) SPOINT

Description This specifies how constraints should be applied to the warping SPOINTs of unmatched ends within the application region (see continuity rules below). 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 are 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.

* The GA/GB fields of the CBEAM are the node IDs to which this element is associated. 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

Main Index

Chapter 2: Building A Model Element Properties

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. The general rules of implied continuity are as follows. 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 restriction 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. In versions before Patran 2001r3, 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.

Main Index

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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 automatically, 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.

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

This creates the following MSC Nastran element and associated materials: Table 2-53 General Section Linear/Cubic Closed Beam (CBEAM) Element

Allowable Material

Material Entry

CBEAM/PBEAM/ PBEMN1 (INT2=LCC)

Isotropic

MAT1/MAT4

CBEAM/PBEAML/ PBEMN1 (INT2=LCC)

Isotropic

MAT1/MAT4

Use this form to create CBEAM elements with a PBEAM or PBEAML property and associated PBEMN1 to define nonlinear, large displacement, large strain behavior. A PBEMN1 entry is written with BEAM option written to the BEH2 field and LCC written to the INT2 field. Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 101 for the generic properties needed for any beam/bar definition. Simply substitute CBEAM for CBAR and PBEAM/PBEAML for PBAR/PBARL as appropriate. Whether a PBEAM or a PBEAML property entry is written is dependent on the setting of the Section Name pull down. Properties writes a PBEAM, and Dimensions writes a PBEAML.

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.

Main Index

Action

Dimension

Type

Option 1

Option 2

Topologies

Create Modify

1D

Beam

General Section

Standard Formulation

Bar/2

Chapter 2: Building A Model Element Properties

This creates the following MSC Nastran element and associated materials: Table 2-54 General Section Linear/Cubic Open Beam (CBEAM) Element

Allowable Material

Material Entry

CBEAM/PBEAM/ PBEMN1 (INT2=LCO)

Isotropic

MAT1/MAT4

CBEAM/PBEAML/ PBEMN1 (INT2=LCO)

Isotropic

MAT1/MAT4

Use this form to create CBEAM elements with a PBEAM or PBEAML property and associated PBEMN1 to define nonlinear, large displacement, large strain behavior. A PBEMN1 entry is written with BEAM option written to the BEH2 field and LCO written to the INT2 field Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 101 for the generic properties needed for any beam/bar definition. Simply substitute CBEAM for CBAR and PBEAM/PBEAML for PBAR/PBARL as appropriate. Whether a PBEAM or a PBEAML property entry is written is dependent on the setting of the Section Name pull down. Properties writes a PBEAM, and Dimensions writes a PBEAML.

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

This creates the following MSC Nastran element and associated materials: Table 2-55 General Section Linear Shear Beam (CBEAM) Element

Allowable Material

Material Entry

CBEAM/PBEAM/ PBEMN1 (INT2=LS)

Isotropic

MAT1/MAT4

CBEAM/PBEAML/ PBEMN1 (INT2=LS)

Isotropic

MAT1/MAT4

Use this form to create CBEAM elements with a PBEAM or PBEAML property and associated PBEMN1 to define nonlinear, large displacement, large strain behavior. A PBEMN1 entry is written with BEAM option written to the BEH2 field and LS written to the INT2 field Please see the description of properties listed in 1D - Beam - General Section (CBAR) - Standard Formulation, 101 for the generic properties needed for any beam/bar definition. Simply substitute CBEAM for CBAR and PBEAM/PBEAML for PBAR/PBARL as appropriate.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Element Properties

Whether a PBEAM or a PBEAML property entry is written is dependent on the setting of the Section Name pull down. Properties writes a PBEAM, and Dimensions writes a PBEAML.

1D - Rod - General Section (CROD/CONROD1) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Create Modify

1D

Rod

Option 1

Option 2

Topologies Bar/2

This creates the following MSC Nastran element and associated materials: Table 2-56 Rod (CROD/CONROD) Element

Material Entry

CROD/CONROD

Isotropic

MAT1/MAT4

CONROD

Isotropic

MAT1/MAT4

1

Main Index

Allowable Material

To control whether a CROD entry, which uses a separate property entry, or a CONROD, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

Chapter 2: Building A Model Element Properties

The allowable properties are described below. This defines a tension-compression-torsion element of the structural model. Table 2-57 General Section Rod Properties (CROD/CONROD*) Property

Bulk Data (field)

Description

Material Name

CONROD (M) PROD (M)

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 or PROD entry. This property is required.

Area

CONROD (A) PROD (A)

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

Torsional Constant

CONROD (J) PROD (J)

Defines the torsional stiffness of the beam. This is the J field on the CONROD or 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

CONROD (C) PROD (C)

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

Nonstructural Mass

CONROD (NSM) PROD (NSM)

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 CONROD or 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

BCBMRAD

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 input file. You must turn on beam-to-beam contact in the Contact Detection form.for this parameter to be written. See Contact Detection, 305.

* The G1/G2 fields of the CROD/CONROD are the node IDs to which this element is associated.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Element Properties

1D - Spring (CELAS1/CELAS21) 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

This creates the following MSC Nastran element and associated materials: Table 2-58 Scalar Spring (CELAS1/CELAS2*) Element

Allowable Material

Material Entry

CELAS1/PELAS

Not Applicable

None

CELAS2

Not Applicable

None

* Note that these elements are NOT written to the input file if only thermal Load Steps are defined for the analysis. There must be at least one structural Load Step defined.

1

Main Index

To control whether a CELAS1 entry, which uses a separate property entry, or a CELAS2, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

Chapter 2: Building A Model Element Properties

The allowable properties are described below. This defines a scalar spring element of the structural model. Table 2-59 Scalar Spring Properties (CELAS1/CELAS2*) Property

Bulk Data (field)

Description

Spring Constant

PELAS (K) CELAS2 (K)

Defines the coefficient to be used for this spring. This is the K field on the CELAS2 or PELAS entry. This can either be a real value or a reference to an existing field definition. This property is required.

Damping Coefficient

PELAS (GE) CELAS2 (GE)

Defines what damping is to be included. This is the GE field on the CELAS2 or PELAS entry. This property can either be a real value or a reference to an existing field definition. This property is optional.

Stress Coefficient

PELAS (S) CELAS2 (S)

Defines the relationship between the spring deflection and the stresses within the spring. This property is the S field on the CELAS2 or 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 DOF at Node 2

CELAS1 (C1/C2) CELAS2 (C1)

Defines which degree of freedom this value is to be attached to. This can be set to UX, UY, UZ, RX, RY, or RZ. These properties defines the setting of the C1 and c2 field on the CELAS1 or CELAS 2entry. This property is required.

* The G1/G2 fields of the CELAS1/CELAS2 are the node IDs to which this element is associated.

1D - Damper - Scalar (CDAMP1/CDAMP21) 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

1

Main Index

To control whether a CDAMP1 entry, which uses a separate property entry, or a CDAMP2, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

121

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Element Properties

This creates the following MSC Nastran element and associated materials: Table 2-60 Scalar Damper (CDAMP1/CDAMP2*) Element

Allowable Material

Material Entry

CDAMP1/PDAMP

Not Applicable

None

CDAMP2

Not Applicable

None

* Note that these elements are NOT written to the input file if only thermal Load Steps are defined for the analysis. There must be at least one structural Load Step defined. The allowable properties are described below. This defines a scalar damper element of the structural model. Table 2-61 Scalar Damper Properties (CDAMP1/CDAMP2*) Bulk Data (field)

Property

Description

Damping Coefficient

PDAMP (B) CDAMP2 (B)

DOF at Node 1 DOF at Node 2

CDAMP1 (C1/C2) Defines which degree of freedom this value is to be attached to. CDAMP2 (C1/C2) This property can be set to UX, UY, UZ, RY, or RZ and defines the setting for the C1 and C2 fields on the CDAMP1 or CDAMP2 entry. This property is required.

Defines the force per unit velocity value to be used. This property is the B field on the CDAMP2 or PDAMP entry and can either be a real value or a reference to an existing field definition. This property is optional.

* The G1/G2 fields of the CDAMP1/CDAMP2 are the node IDs to which this element is associated.

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

This creates the following MSC Nastran element and associated materials: Table 2-62 Viscous Damper (CVISC) Element CVISC/PVISC

Main Index

Allowable Material Not Applicable

Material Entry None

Chapter 2: Building A Model Element Properties

The allowable properties are described below. This defines a viscous damper element of the structural model. Table 2-63 Scalar Damper Properties (CDAMP1/CDAMP2*) Bulk Data (field)

Property

Description

Extensional Viscous Coefficient

PVISC (CE)

This is the CE 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

PVISC (CR)

This is the CR 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.

* The G1/G2 fields of the CVISC are the node IDs to which this element is associated.

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 This creates the following MSC Nastran element and associated materials: Table 2-64 Adaptive or NonAdaptive Gap (CGAP) Element CGAP/PGAP

Main Index

Allowable Material Not Applicable

Material Entry None

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The allowable properties are described below. This defines a gap or frictional element of the structural model for nonlinear analysis. Table 2-65 Adaptive or NonAdaptive Gap Properties (CGAP*) Property

Main Index

Bulk Data (field)

Description

Gap Orientation

CGAP (CID) CGAP (G0) CGAP (X1-X3)

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

PGAP (U0)

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

PGAP (F0)

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

PGAP (KA) PGAP (KB)

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.

Sliding Stiffness

PGAP (KT)

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.

Chapter 2: Building A Model Element Properties

Table 2-65 Adaptive or NonAdaptive Gap Properties (CGAP*) (continued) Bulk Data (field)

Property

Description

Static Friction

PGAP (MU1)

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

PGAP (MU2)

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

PGAP (TMAX)

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. Used with the Adaptive options only. Set to -1 for NonAdaptive.

Max Adjust Ratio PGAP (MAR)

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

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.

PGAP (TRMIN)

* The GA/GB fields of the CGAP are the node IDs to which this element is associated.

1D - Scalar Mass (CMASS1/CMASS21) 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

1

Main Index

Option(s)

Topologies Bar/2

To control whether a CMASS1 entry, which uses a separate property entry, or a CMASS2, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

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This creates the following MSC Nastran element and associated materials: Table 2-66 Scalar Mass (CMASS1/CMASS2) Element

Allowable Material

Material Entry

CMASS1/PMASS

Not Applicable

None

CMASS2

Not Applicable

None

The allowable properties are described below. This defines a scalar mass element of the structural model. Table 2-67 Scalar Mass Properties (CMASS1/CMASS2*) Property

Bulk Data (field)

Description

Mass

CMASS2 (M) PMASS (M)

DOF at Node 1 DOF at Node 2

CMASS1 (C1/C2) Defines which degree of freedom this value will be attached to. CMASS2 (C1/C2) 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.

Defines the translation mass or rotational inertia value to be applied. This is the M field on the CMASS2 or PMASS entry. This property can be either a real value or a reference to an existing field definition. This property is required.

* The G1/G2 fields of the CMASS1 or CMASS2 are the node IDs to which this element is associated.

1D - Conductor (CELAS1/CELAS21) This describes the Input Properties available from the Element Properties form when the following options are chosen. Action

Dimension

Type

Create Modify

1D

Conductor

1

Main Index

Option(s)

Topologies Bar/2

To control whether a CELAS1 entry, which uses a separate property entry, or a CELAS2, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

Chapter 2: Building A Model Element Properties

This creates the following MSC Nastran element and associated materials: Table 2-68 Conductor (CELAS1/CELAS2*) Element

Allowable Material

Material Entry

CELAS1/PELAS

Not Applicable

None

CELAS2

Not Applicable

None

* Note that these elements are NOT written to the input file if only structural Load Steps are defined for the analysis. There must be at least one thermal Load Step defined. The allowable properties are described below. This defines a conductor element of the thermal model. Table 2-69 Conductor Properties (CELAS1/CELAS2*) Property Thermal Conductance

Bulk Data (field) PELAS (K) CELAS2 (K)

Description This defines a simple conductance link between two nodes in the model. This value can either be real or a reference to an existing field definition.

* The G1/G2 fields of the CELAS1/CELAS2 are the node ID to which this element is associated.

1D - Capacitor (CDAMP1/CDAMP21) This describes the Input Properties available from the Element Properties form and the following options are chosen. Action

Dimension

Type

Create Modify

1D

Capacitor

Option(s)

Topologies Bar/2

This creates the following MSC Nastran element and associated materials: Table 2-70 Capacitor (CDAMP1/CDAMP2*) Element

Allowable Material

Material Entry

CDAMP1/PDAMP

Not Applicable

None

CDAMP2

Not Applicable

None

* Note that these elements are NOT written to the input file if only structural Load Steps are defined for the analysis. There must be at least one thermal Load Step defined. 1

Main Index

To control whether a CDAMP1 entry, which uses a separate property entry, or a CDAMP2, which places properties directly on the element entry, you must set the toggle Write Properties on Element Entries on the Translation Parameters form. See Translation Parameters, 291.

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The allowable properties are described below. This defines a scalar conductor element of the thermal model. Table 2-71 Capacitor Properties (CELAS1/CELAS2*) Property Thermal Capacitance

Bulk Data (field) PDAMP (B) CDAMP2 (B)

Description This defines a simple thermal capacitance link between two nodes in the model. This value can either be real or a reference to an existing field definition.

* The G1/G2 fields of the CDAMP1/CDAMP2 are the node IDs to which this element is associated.

1D - Scalar Bush (CBUSH) 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

Scalar

Bar/2

This creates the following MSC Nastran element and associated materials: Table 2-72 Scalar Bush (CBUSH) Element CBUSH/PBUSH

Allowable Material Not Applicable

Material Entry None

The allowable properties are described below. The 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

Main Index

Chapter 2: Building A Model Element Properties

or nonlinear force deflection properties are supplied, the PBUSHT entry is also written. Otherwise it is not written. Table 2-73 Scalar Bush Properties (CBUSH*) Property Bush Orientation

Bulk Data (field) CBUSH (CID)

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 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.

Bush Orientation (cont.)

CBUSH (X1-X3)

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.

CBUSH (G0)

If Node ID is specified, the vector is determined from GA to G0. If no orientation is specified in any form, the element xaxis 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 (0.0 ≤ s ≤ 1.0) specifies the springdamper location along the line from GA to GB by setting the fraction of the distance from GA. s=0.50 centers the spring-damper.

Offset Location

CBUSH (S)

Offset Orientation System

CBUSH (OCID)

Specifies the coordinate system used to locate the springdamper offset when it is not on the line from GA to GB.

Offset Orientation Vector

CBUSH (S1-S3)

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.

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Table 2-73 Scalar Bush Properties (CBUSH*) (continued) Property

Bulk Data (field)

Description

Spring Constant i

PBUSH (K1-K6)

Defines the stiffness associated with a particular degree of freedom. This property is defined in terms of force per unit displacement and is a real value.

Stiff. Freq Depend i

PBUSHT (“K”) TABLED1

Defines the stiffness associated with a particular degree of freedom in terms of force per unit displacement and is to reference an existing field definition for defining stiffness vs. frequency. The field must use frequency as its variable.

Stiff. Force/Disp i

PBUSHT(“KN”) TABLED1

Defines the nonlinear force/displacement curves for each degree of freedom of the spring-damper system and is to reference an existing field definition defining force vs. displacement. The field must use displacement as its variable.

Damping Coefficient i

PBUSH(B1-B6)

Defines the force per velocity damping value for each degree of freedom. This property is defined in terms of force per velocity and is a real value.

Damp. Freq Depend i

PBUSHT(“GE”) TABLED1

Defines the force per velocity damping value for each degree of freedom. This property is a reference to an existing field definition for defining damping vs. frequency. The field must use frequency as its variable.

Structural Damping

PBUSH (GE1)

Defines the non-dimensional structural damping coefficient (GE1). This property is a real value.

Struc. Damp Freq Depend

PBUSHT(“GE”) TABLED1

Defines the non-dimensional structural damping frequency tables. These properties are references to existing field definitions for defining damping vs. frequency. The fields must use frequency as their variables.

Stress Recovery Translation Stress Recovery Rotation

PBUSH (SA, ST)

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

Strain Recovery Translation Strain Recovery Rotation

PBUSH (EA, ET)

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

Force-Deflection Curve PBUSHT (FDC) Rule

Main Index

Force deflection curve rule - writes FDC field of PBUSHT.

Fuse Behavior

PBUSHT (FUSE) Fuse behavior. Writes the FUSE field of PBUSHT

Fuse Direction

PBUSHT (DIR)

Fuse direction. Writes the DIR field of PBUSHT.

Chapter 2: Building A Model Element Properties

Table 2-73 Scalar Bush Properties (CBUSH*) (continued) Property

Bulk Data (field)

Description

Fuse Failure Mode

PBUSHT (OPTION)

Failure mode. Writes the OPTION field of PBUSHT.

Lower Failure Bound Upper Failure Bound

PBUSHT (LOWER, UPPER)

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

FRATE-K Drop Scale Factor

PBUSHT(FSRS)

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

Grid A Rotation

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

* The GA/GB fields of the CBUSH are the node IDs to which this element is associated.

1D- 2D Linear/Nonlinear Bush (CBUSH2D) 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/nonlinear

Bar/2

This creates the following MSC Nastran element and associated materials: Table 2-74 2D Linear/Nonlinear Bush (CBUSH2D) Element

Allowable Material

CBUSH2D/PBUSH2D

Not Applicable

Material Entry None

The allowable properties are described below for defining linear and nonlinear properties of a bush element. Table 2-75 2D Linear/Nonlinear Bush Properties (CBUSH2D*) Property Bush Orientation System

Main Index

Bulk Data (field)

Description

CBUSH2D (CID)

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

Bush Orientation Plane CBUSH2D (PLANE)

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

Stiffness K11

PBUSH2D (K11)

Nominal stiffness in T1 rectangular direction. Required!

Stiffness K22

PBUSH2D (K22)

Nominal stiffness in T2 rectangular direction. Required!

[Damping B11]

PBUSH2D (B11)

Nominal damping in T1 rectangular direction. Default = 0.0

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Table 2-75 2D Linear/Nonlinear Bush Properties (CBUSH2D*) (continued) Property

Bulk Data (field)

Description

[Damping B22]

PBUSH2D (B22)

Nominal damping in T2 rectangular direction. Default = 0.0

[Force M11]

PBUSH2D (M11) Nominal acceleration-dependent force in T1 rectangular direction. Default = 0.0

[Force M22]

PBUSH2D (M22) Nominal acceleration-dependent force in T2 rectangular direction. Default = 0.0

[Inner Journal Diameter BDIA]

PBUSH2D (BDIA)

Inner journal diameter. Real > 0.0

[Damper Length BLEN]

PBUSH2D (BLEN)

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

[Damper Radial Clearance BCLR]

PBUSH2D (BCLR)

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

[Solution Option SOLN]

PBUSH2D (SOLN)

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

[Lubricant viscosity VISCO]

PBUSH2D (VISCO)

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

[Lubricant Vapor Pressure PVAPCO]

PBUSH2D (PVAPCO)

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

[Number of Lubricant Ports NPORT]

PBUSH2D (NPORT)

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

[Boundary Pressure for Port 1]

PBUSH2D (PRES1)

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

[Angular Positions for Port 1]

PBUSH2D (THETA1)

Angular position for port 1. (0.0 0.0, overlap between bodies. For values 0.0, overlap between bodies. For values Analysis (p. 388) in the Patran Reference Manual

Available Jobs

To restore the settings of previous analysis jobs, select one from the list. A new job is added to the list when the Apply button is pressed. If one of these jobs is selected, the name appears in the Job Name list box and all parameters for this job are 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

Job name of the analysis. The resulting input deck inherits the name and is called .bdf by default. All resulting MSC Nastran files and message files inherit this name.

Job Description

TITLE=

The description of the analysis job. This is written directly to the TITLE key word in the MSC Nastran Case Control above all SUBCASES and STEPs

SUBTITLE

SUBTITLE=

Writes the SUBTITLE key word in the MSC Nastran Case Control above all SUBCASES and STEPs

LABEL

LABEL=

Writes the LABEL key word in the MSC Nastran Case Control above all SUBCASES and STEPs

Main Index

Chapter 3: Running an Analysis Review of the Analysis Form

Table 3-2 Analyze Options Action

Case Control

Description

Select Group...

When the Object is set to Selected Group, this button displays a form from which to select the group. The default is to use the Current Group. See The Group Menu (p. 225) in the Patran Reference Manual for more details on creating groups of FEM entities.

Translation Parameters...

Define and manage global, job specific translation parameters for the current analysis. See Translation Parameters, 291.

Solution Parameters...

Define and manage global, job specific solution parameters for the current analysis. See Solution Parameters, 298.

Direct Text Input...

Define additional MSC Nastran keywods and comments to include in various sections of the translated input deck. See Direct Text Input, 312.

Load Steps...

Define and manage Load Steps including solution parameters and output request. See Load Steps, 314.

Load Step Select...

Select Load Steps for the currently defined job. See Load Step Select, 383.

Analysis Manager...

Invokes the Analysis Manager for job submittal, monitoring, and management. Only available if the Analysis Manager is installed, licensed, and properly configured. See the Patran Analysis Manager User’s Guide for details.

Apply

Press this button to save the job and all its parameters and associated Load Steps to the database and if requested with the appropriate Method, submit the job to MSC Nastran.

Overview of Analysis Job Definition and Submittal To submit a single Load Step, non-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 are made automatically. Other solution types or multiple Load Steps will require access to one or more lower-level forms. Several different analysis examples are considered below. To perform a multiple Load Step, non-linear static analysis, it is necessary only to open the Load Step Select... form. Load Steps with the with appropriate defaults can be selected for inclusion in the job. If a change to one or more parameters for a Load Step is desired (e.g., to change an output request), the Load Steps...form must be accessed. Then it is simple to select a Load Step 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 Load Steps... form and set the Analysis Type and press Apply on this form to create an appropriate Load Step with pre-set defaults. Only if the default parameters need to be changed, will it be necessary to access subordinate forms on the Load Steps... form. In the Patran MSC Nastran Implicit Nonlinear Interface, a Load Step 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 Load Steps 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 Load Step may be used interchangeably.

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Access Results Once an analysis has been completed the Access Results Action is used to import or attach the results file to Patran for general postprocssing.

A short description of each item on this form is given in the table below. For more details on this and the supported results entities, please refer to the section on MSC Nastran Results Access, 390.

Main Index

Chapter 3: Running an Analysis Review of the Analysis Form

Table 3-3 Access Results Options Action Object

Description With the Action set to Access Results, the available Objects are: 

Attach HDF5- select an MSC Nastran NH5RDB (.h5) file from which to access results.



Attach Master- select an MSC Nastran MASTER file from which to access results.



Attach OP2- select an MSC Nastran OP2 file from which to access results.

With the Action set to Delete, the available Objects to remove results attachments are: 

MASTER Attach - disconnects from the MASTER file.



OP2 Attachment- disconnects from the OP2 file.

Deleting results attachments does not delete results or affect these files in any way since the results were never imported into the database. The results simply are no longer accessible. Method

Based on the Object set, the Methods are: 

Results Entities- access only the result entities contained in the attached file.



Model Data- import the model data (nodes/elements) only from the attached file.



Both - import the model data (nodes/elements) and the result entities from the attached file.

Select Results File

Use this file browser to select the file of interest. By default you may simply press the Apply button without selecting a file and a file with the name of the Job Name appended with the appropriate suffix, such as MASTERor op2, respectively, will be attached if the file exists.

Translation Parameters...

Displays a form for selecting various translation parameters associated with importing/accessing results. Please see Results Translation Parameters, 394.

Entity Selection...

Displays a form for selecting various FEM entities to import. Please see Entity Selection Form, 404.

Apply

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Press the Apply button to attach the results file.

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Read Input File To import an MSC Nastran input deck to the Patran database, set the Action to Read Input File

Main Index

Chapter 3: Running an Analysis Review of the Analysis Form

A short description of each item on this form is given in the table below. For more details on this and the supported MSC Nastran entities, please refer to the section on MSC Nastran Input File Import, 401. Table 3-4 Read Input File Options Action Object

Description With the Action set to Read Input File, the available Objects only: 

Entity Selection...

Model Data- import the model data from the MSC Nastran input file

Displays a form for selecting various FEM entities to import. Please see Entity Selection Form, 404.

Select Input File

Use this file browser to select the file of interest.

Apply

Press the Apply button to attach the results file.

Main Index

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Delete Analysis Job To delete an existing analysis job, set the Action to Delete on the Analysis form. Simply select the job of interest and press the Apply button. The Apply button remains disabled until a job is selected, at which time it is then enabled for the deletion.

Main Index

Chapter 3: Running an Analysis Review of the Analysis Form

Monitor To monitor an existing analysis job, set the Action to Monitor on the Analysis form. Simply select the job of interest and ensure the Job Name is displayed in the Job Name data box.

Main Index

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A short description of each item on this form is given in the table below. Table 3-5 Monitor Options Action

Description

View F06 File...

Opens the .f06 file in an editor.

View F04 File...

Opens the .f06 file in an editor.

View log File...

Opens the .log file in an editor.

Search Keywords...

Opens a form to allow you to enter key words to search for in a file. See below.

View STS File...

Opens the .sts file in an editor.

Apply

Pressing the Apply button launches the Analysis Manager if the Analysis Manager is installed, licensed, and properly configured. If not, a simple form appears that monitors the status and log files while the job is running. The simple form has three buttons for stopping and starting the monitoring (Stop and Go), and to close the form (Cancel). Please be aware that sometime it takes awhile for a job to begin and the monitoring form may appear frozen during this time.

Search Keywords:

Table 3-6 Search Keyword Options Action

Description

Enter Key Words

Enter the key words or phrases to search for in the file each on its own line.

Line Numbering

Turn On if you want the line number identified where it found a keyword or phrase.

Case Insentitive

Turn OFF if you want the search to consider case.

Select Search File

Type the name of the file (with path if necessary) or use the Browser button to select a file.

Main Index

Chapter 3: Running an Analysis Review of the Analysis Form

Table 3-6 Search Keyword Options Action

Description

OK

Closes the form and saves the settings for the duration of the Patran session.

Defaults

Sets the key words and other settings on the form back to the defaults.

Cancel

Closes the form and resets the values to what they were before the form was opened.

Apply

Performs the keyword search on the selected file and displays the results in an editor.

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Note: The editor used to display the files when the various buttons on this form are pressed can be customized. By default the editor is “notepad” on Windows and “xterm -exec vi” on Linux. By setting the environment variable P3_EDITOR, you may define any editor of your choice. Please note that the command to execute any defined editor must be present in your “path”. If you can type the editor command in a command window, then it should work. Abort Job To abort an existing analysis job, set the Action to Abort on the Analysis form, select an Existing Job and

Main Index

Chapter 3: Running an Analysis Review of the Analysis Form

simply press the Apply button..

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Note: This functionality is only available with the Analysis Manager installed, licensed, and properly configured. The job may be currently running or completed. If completed, then the status of the complete job is displayed. Run Demo To run an a demonstration problem, set the Action to Run Demo on the Analysis form, select an Demo and simply press the Apply button..

Note: Demonstration problems exist for various Analysis Types and the Preference is changed to the appropriate Analysis Type when executed. Only SOL 400 jobs are meant for the Implicit Nonlinear Analysis Type. Setting the Method to Full Run actually submits the job to run through MSC Nastran. Some jobs may take awhile. So be sure that this is your intention before pressing Apply. If you simply want it to recreate the input deck without the analysis and results plotting, set the Method to Analysis Deck.

Main Index

Chapter 3: Running an Analysis Translation Parameters

Translation Parameters This form is accessed directly from the main Analysis form. Translation parameters define output file formats, numerical tolerances, processing options, numbering offsets, and external include files. Note that if all default values are acceptable, it is not necessary to access and/or modify any settings on this form. Each item is explained in the table below.

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Table 3-7 Translation Parameters nastran command Case Control Bulk Data (field)

Option

Description

MSC Nastran Version

Specifies the version of MSC Nastran. The version specified here is used for two purposes: to determine various bulk data entry formats to use and to submit the job to the specified version as configured using the site_setup or P3_TRANS.INI file. Use only whole numbers; for example, 2014, 2014.. This version number can be overridden by setting the environment variable “NASTRAN_VERSION”.

Tolerances



Division - prevents divide by zero errors.



Numerical - determines if two real values are equal.



Writing - determines if a value is approximately zero when writing a bulk data entry.

Number of Tasks

smp=number

Represents the number of processors to be used to run an analysis. It is assumed that the environment is configured for distributed parallel processing. Bulk Data Format

Data Deck Echo

ECHO

Sorted Bulk Data

This setting specifies whether the resulting MSC Nastran input file from the translation should be output with the bulk data entries sorted in alphabetical order or left as the standard translation creates the input file. If Yes, a Check Run MSC Nastran analysis is actually submitted to convert the input file to a sorted deck.

Card Format

Determines whether real numbers are written to a standard (8 character) MSC Nastran field or to a double (16 character) MSC Nastran field. If Either is set, the precision necessary determines whether an 8 or 16 character field is used. The following preference can be included in the settings.pcl file to set the default:

Indicates how the data file entry images are to be printed in the MSC Nastran print (f06) file. This controls the setting used for the ECHO Case Control command. This parameter can have one of three settings: Sorted, Unsorted, or None.

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. Precision Control Options...

Main Index

Opens a subform to specify 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. See Precision Control, 295 for details.

Chapter 3: Running an Analysis Translation Parameters

Table 3-7 Translation Parameters

Option Numbering Options...

nastran command Case Control Bulk Data (field)

Description

Opens a subform used to indicate offsets for all IDs to be automatically assigned during translation. See Numbering Options, 296 for details.

Bulk Data Include File... Prompts you for the filename of the include file to be imported as part of the translation. See Bulk Data Include File, 298 for details. GRID (CP, CD)

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. The CD field is always the Analysis Frame coordinate as defined in Patran when creating nodes/meshing.

Write Properties on Element Entries

CELAS1 vs CELAS2 CDAMP1 vs CDAMP2 CMASS1 vs CMASS2 CROD vs CONROD

Specifies that properties be written to the element entries for all elements where it is allowed.

Write Continuation Markers

This option is OFF by default. This option can be turned ON to write continuation markers for bulk data entries.

Write Global Ply IDs

PCOMP vs PCOMPG

When ON, attempts to keep the Global Ply IDs consistent between MSC Nastran and Patran.

Convert CBARs to CBEAMs

MDLPRM (BRTOBM=-1)

Converts all CBARs to CBEAMS if turned ON. OFF by default.

Node Coordinates

Coordinate Frame Coordinates

Results Output*: Specifies output of data to a MSC Nastran OUTPUT2 file (*.op2).

OP2

PARAM, POST, 1

Print

Print - Specifies output of data to the MSC Nastran print file (*.f06). See the footnote below this table.

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Table 3-7 Translation Parameters

Option

nastran command Case Control Bulk Data (field)

Description

Punch

Punch - Specifies output of data to a MSC Nastran punch file (*.pch). See the footnote below this table.

MASTER only MASTER/DBALL

NASTRAN SYSTEM(316)=7

MASTER/DBALL

NASTRAN SYSTEM(316)=19 MASTER/DBALL - When ON, both a MASTER file and a DBALL file are written. When this is ON, the MASTER Only toggle must be OFF.

HDF5 (Compressed) (No Rot.DOFs)

MDLPRM,HDF5,0/1 MDLPRM,H5NORDOF,1

When ON, only a MASTER file is written. If this is, ON, the MASTER/DBALL toggle must be OFF.

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. *The ability to write PRINT, PUNCH, and PLOT settings to the output variables such as DISPLACEMENT, STRESS, etc., is controlled in two places. It is controlled globally on this Translation Parameters form if the Print or Punch toggles are ON/OFF. If Punch is OFF, then the ability to set PUNCH is done by individual output request on the Output Requests, 362 form in Advanced mode. The ability to suppress the PRINT by using PLOT is also done on the Output Request form. If the Suppress Print toggle is set ON on the Output Request form, then no PRINT option is written and a PLOT option is written instead. If Punch toggle is ON on the Translation Parameters form, ALL output requests will get the PUNCH option regardless of the settings on the Output Requests form. If the Print toggle is OFF on the Translation Parameter form, then ALL output requests will get the PLOT option regardless of the settings on the Output Requests form. If the toggle is ON, then the setting for Suppress Print will be honored on the Output Request form.

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Chapter 3: Running an Analysis Translation Parameters

Precision Control This form is accessed by the Precision Control Options... button on the Translation Parameters form and is used for controlling the precision (number of significant digits) written to the bulk data entries for properties and values for nodes (Grids), coordinate frames, MPCs, loads and boundary conditions (LBCs), materials, and element properties. The data associated with each one of these can be controlled separately by adjusting the associated slider bars.

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Numbering Options This form is accessed 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 user types 100 into the Element Properties offset box, the numbering of element properties in the resulting MSC Nastran input file will begin at 101.

Other options are explained in the table below.

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Chapter 3: Running an Analysis Translation Parameters

Table 3-8 Numbering Options Option

Description

Automatic Numbering Offsets

Enter a number in any of these databoxes to control the starting ID number of the entities in question. The first ID produced will be one (1) greater than the number supplied. So if you want IDs to start with 101, enter 100.

Begin. Contin. Marker

This box allows the user to specify the continuation of the mnemonic format used on multiple line, bulk data entries.

IDs Encoded in Names

IDs Encoded in Names allows the user to activate recognition of IDs encoded into the name of any named entity, such as a material. The names are written as comments above the actual bulk data entry. For example, a PSHELL entry may be written with a comment above it in this manner: $ Pset: “plate” will be imported as : “pshell.1” The Patran property name is “plate’, and the ID of the PSHELL is embedded in the “pshell.1” string as ID 1. The following options are available.

Number Only

This recognizes and uses 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

This recognizes an ID if the number begins the name, such as “52_shell_property.” This option is OFF by default.

Trailing Number

This recognizes an ID if it trails the name, such as “shell_property_52.” This option is OFF by default.

Encoded Syntax

This recognizes 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.

Syntax Marker

This is the syntax marker used for the Encoded Syntax option, defaulted to “.”.

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 an MSC 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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Bulk Data Include File This form is accessed by the Bulk Data Include File... button on the Translation Parameters form. Type in the file name or select the file of the include file using the file browser function. The contents of the file are copied into the start of the bulk data section on translation. If you would prefer that the MSC Nastran INCLUDE option be used instead of literally copying the contents of the file, please use the Direct Text Input option, which allows you to place any valid MSC Nastran commands, entries, or comments in various locations of the input file. See Direct Text Input, 312.

Solution Parameters This subordinate form appears when the Solution Parameters... button is selected on the main Analysis form. Note that if all default values are acceptable, it is not necessary to access and/or modify any settings on this form.

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Chapter 3: Running an Analysis Solution Parameters

Items on this form are described in the table below.

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Table 3-9 Solution Parameters Option

Case Control Bulk Data (field)

Description

Automatic Constraints

AUTOSPC(RESIDUAL)=

Places an AUTOSPC entry in the Case Control if ON so that MSC Nastran automatically constrains model singularities.

Assumed Strain

NLMOPTS (ASSM)

The NLMOPTS entry is written with the ASSM or OFF option, if toggle is ON or OFF, respectively. This is a global setting and forces all elements that can use this formulation to adopt it. By default this is ON.

Shell Shear Correction

NLMOPTS (TSHEAR)

If ON, forces all shell elements using nonlinear formulations to use the shear correction.

Creep

NLMOPTS (CREEP)

If ON, enables the Creep Formulation frame and writes the selected NLMOPTS CREEP options to deck. For more information about Implicit Creep Analysis, see Static Analysis Step Parameters & Options, Elastoplastic Material Properties (Yield Function) and Viscoplastic Material Properties.

Implicit Creep

NLMOPTS (CREEP valc3)

If ON, NLMOPTS (CREEP valc3) will be set to 1 for Implicit Creep formulation else Explicit Creep formulation.

Implicit Creep Method

NLMOPTS (CREEP valc4)

For Implicit Creep formulation, three options are available: Elastic Tangent, Secant Tangent, and Radial Return. NLMOPTS (CREEP valc4) field will be set to Blank or 0 for Elastic Tangent option, 1 for Secant Tangent and 2 for Radial Return option. The recommended value is 1 (Secant Tangent).

Nonlinear Geometric Effects

PARAM,LGDISP,1

Defines the type of geometric or material nonlinearity to be included in the load step. Writes the PARAM if set to Large Displacement (default). Otherwise it is not written.

Follower Loads

PARAM,LGDISP,2

Specifies whether forces will follow displacements. Writes the PARAM if set to No Follower Loads. Otherwise the PARAM setting for Nonlinear Geometric Effects is written.

Residual Vectors

RESVEC

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.

Mass Calculation

COUPMASS

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.

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Chapter 3: Running an Analysis Solution Parameters

Table 3-9 Solution Parameters Option

Case Control Bulk Data (field)

Description

Struct. Damping Coeff.

PARAM (G)

Defines a global damping coefficient to applied. This defines the G parameter (e.g., PARAM, G, value).

W3, Damping Factor

PARAM (W3)

W4, Damping Factor

PARAM (W4)

Define W3 and W4 parameters. These parameters alter the damping characteristics of the model.

Wt-Mass Conversion

PARAM (WTMASS)

Defines the conversion factor between weight and mass measures.

Node ID for Wt. Gener. PARAM (GRDPNT)

Indicates the node ID that is to be used for the Grid Point Weight Generator.

Default Initial Temperature

TEMPERATURE(INITIAL)= TEMPD

Allows for specification of a general initial temperature TEMPD entries are written with Case Control TEMPERATURE(INITIAL) calling out the corresponding TEMPD entries in the bulk data. Blank by default and no TEMPD entries written.

Default Load Temperature

TEMPERATURE(LOAD) TEMPD

Allows for specification of a general loading temperature. TEMPD entries are written with Case Control TEMPERATURE(LOAD) entries calling out the corresponding TEMPD entries in the bulk data. Blank by default and no TEMPD entries written.

Contact Parameters...

Opens the Contract Control Parameters form. See Contact Control Parameters, 302. More options for controlling general contact methods, detection, separation, friction/sliding, augmentation and initial contact are provided on this form.

OK

Closes the form and saves any data change on it or any of its subordinate forms, which are also subsequently closed. Note that the data is not actually saved with the job until the Apply button is pressed on the main Analysis form.

Defaults

Resets all values on the form to their defaults.

Cancel

Closes the form and discards any changes made on this form and reverts the values back to their state before the form was opened.

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Contact Control Parameters This form is accessed directly from the Solution Parameters form. It is used to defines options for setting contact methods, detection, separation, friction/sliding, augmentation, and initial contact.

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Chapter 3: Running an Analysis Solution Parameters

Items on this form are described in the table below. Table 3-10 Contact Control Parameters Option

Bulk Data (field)

Description

Contact Method

BCPARA (METHOD) Node-to-Segment is the default contact method for MSC Nastran. If set to Segment-to-Segment, the Friction and Augmentation forms are unique to this method.and some items under Contact Detection and Separation are disabled.

Default Penalty Factor Calculation

NASTRAN SEGLOG=1

Sets the default calculation method for the penalty factor for Segment-to-Segment contact. Disabled if Node-to-Segment. Note that the default in Patran is opposite the default used by MSC Nastran. Average Elastic Stiffness: Uses the existing/old logic (MSC Nastran Default) where the default value is based on the average elastic stiffness of the two contact bodies and the default error tolerance. If this is set, NASTRAN SEGLOG is not written as this is the MSC Nastran default. Softer Material/Edge Length: Uses newer logic for PENALT to avoid too large a value for PENALT, where the default value is defined by the body with the softer material and the minimum edge length of the two contact bodies. This logic is often better for thin shell structures. (Patran default.) Turns ON automatic optimization of contact constraint equations, also known as “optimized contact.” Only applicable to Node-to-Segment contact. It is turned ON for all contact bodies or it is turned OFF for all contact bodies. Patran does not allow this parameter to be controlled per contact body.

Optimize Constraint Equations

BCBDPRP (ISTYP)

Contact Detection...

See Contact Detection, 305.

Separation...

See Contact Separation, 306.

Friction/Sliding...

See Friction/Sliding Parameters, 307.

Augmentation Parameters...

See Augmentation Parameters, 308..

Enable Initial Contact

BCONTACT=0 BCTABLE (ID=0)

Main Index

If ON, activates the capability to control initial contact. The initial contact is for creating a BCTABLE with ID = 0 to be used for load increment 0, which causes rigid contact bodies to be moved, and/or to adjust the coordinates of all active nodes on the surface of all deformable bodies to remove any prestressed condition. See the discussion on Initial Contact, 310 below.

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Table 3-10 Contact Control Parameters Option

Bulk Data (field)

Description

Use Contact Table This toggle turns ON the use of contact tables to define the interaction of contact bodies. Please see (s) Contact Table versus Contact Body Pairs, 345 to understand when to use this toggle. It is OFF by default, meaning that contact body interaction is controlled by defining Contact Body Pairs in the Loads and Boundary Conditions (LBCs) application. Please see contact Body Pair, 262. If ON, contact table(s) must be defined. Initial Contact...

This button appears if the Enable Initial Contact toggle is ON. The label on the button depends on whether the Use Contact Table toggle is ON or OFF. If ON, then this allows definition of the initial contact via a contact table. See Initial Contact, 310. If the toggle is OFF, then the button allows access to select a load case containing the contact body pairs that define initial contact conditions.

OK

Closes the form and saves any data change on it or any of its subordinate forms, which are also subsequently closed. Note that the data is not actually saved with the job until the Apply button is pressed on the main Analysis form.

Defaults

Resets all values on the form to their defaults.

Cancel

Closes the form and discards any changes made on this form and reverts the values back to their state before the form was opened.

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Chapter 3: Running an Analysis Solution Parameters

Contact Detection On the Contact Control Parameters subform, select Contact Detection... This form controls general contact parameters for contact detection.

Items on this form are described in the table below. Table 3-11 Contact Detection Parameters Option

Bulk Data (field)

Description

Distance Tolerance

BCPARA (ERROR)

Distance below which a node is considered touching a body (error). Leave the box blank and the tolerance is calculated as the smaller of 1/20 element edge length or 1/4 shell thickness. This global flag is not the preferred method. One should set per body pair either on the Contact Table, 345 or when defining contact Body Pair, 262.

Bias on Tolerance

BCPARA (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. This global flag is not the preferred method. One should set per body pair either on the Contact Table, 345 or when defining contact Body Pair, 262.

Activate 3D Beam-Beam Contact

BCPARA (BEAMB)

Turn this button ON to activate 3D beam-beam contact.

Permanent Gluing

BCPARA (NLGLUE)

Turn this toggle ON to activate Permanent Gluing (NLGLUE=0). If this toggle is OFF, then NLGLUE=1.

OK

Closes the form and saves any data change on it. Note that the data is not actually saved with the job until the Apply button is pressed on the main Analysis form.

Defaults

Resets all values on the form to their defaults.

Cancel

Closes the form and discards any changes made on this form and reverts the values back to their state before the form was opened.

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Note: For Segment-to-Segment contact, not all parameters are available. Those not available are disabled. Contact Separation On the Contact Control Parameters subform, select Separation... This form controls general contact parameters for contact separation.

Items on this form are described in the table below. Table 3-12 Contact Separation Parameters Option

Bulk Data (field)

Description

Maximum Separations

BCPARA (MAXSEP)

Maximum number of separations allowed in each increment. Maximum Separations. Default is 9999. Not used for Segment-to-Segment contact.

Increment

BCPARA (ICSEP)

Flag to control separation. By default (Current), the node separates and an iteration occurs if the force on the node is greater than the separation force. Otherwise (Next) the separation occurs at the beginning of the next increment. Also specifies whether chattering is allowed or not. Increment and Chattering enters the appropriate flag for ICSEP. Chattering is controlled by not allowing a new node that comes into contact during the increment to separate during that increment. Chattering not used by Segment-to-Segment contact.

BCPARA (IBSEP)

Specifies the separation criterion (Forces - default or Stresses) and the critical value at which the separation takes place. The criterion can be based on Relative or Absolute values and stresses based on Force/Area or Extrapolation of integration point stresses. The combination of these settings places the appropriate flag in for IBSEP.

Chattering

Separation Criterion

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Chapter 3: Running an Analysis Solution Parameters

Table 3-12 Contact Separation Parameters Option

Bulk Data (field)

Description

Force Value Stress Value

BCPARA (FNTOL)

OK

Closes the form and saves any data change on it. Note that the data is not actually saved with the job until the Apply button is pressed on the main Analysis form.

Defaults

Resets all values on the form to their defaults.

Cancel

Closes the form and discards any changes made on this form and reverts the values back to their state before the form was opened.

The actual Force/Stress Value to be used as the force/stress to exceed before allowing separation of a node. This is is placed as the FNTOL setting. Automatically calculated if left blank.

Note: For Segment-to-Segment contact, not all parameters are available. Those not available are disabled. Friction/Sliding Parameters On the Contact Control Parameters subform, select Friction/Sliding...

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Items on this form are described in the table below. Table 3-13 Contact Friction/Sliding Parameters Option

Bulk Data (field)

Description

Type

BCPARA (FTYPE)

Available options for friction are: None (default), Bilinear Coulomb, and Bilinear Shear.

Non-Symmetric Matrix

BCPARA (SEGSYM)

Defines whether to use symmetric or non-symmetric friction matrix for Segment-to-Segment contact Note that you must select a solver that supports non-symmetric matrices for this to work. This is done on the Solvers/Options, 334 form.

Sliding

BCPARA (METHOD) For Segment-to-Segment contact, sliding can be based on Small displacement contact or general contact (Finite), in which case a Sliding Threshold can be specified. The METHOD is set to SEGSMALL (Small) or SEGLARGE (Finite), respectively.

Sliding Threshold BCPARA (SLDLMT)

Maximum allowed sliding distance, beyond which the contact segments are redefined, for Segment-to-Segment contact analysis with large deformation.

OK

Closes the form and saves any data change on it. Note that the data is not actually saved with the job until the Apply button is pressed on the main Analysis form.

Defaults

Resets all values on the form to their defaults.

Cancel

Closes the form and discards any changes made on this form and reverts the values back to their state before the form was opened. Note: For Node-to-Segment contact, not all parameters are available. Those not available are disabled.

Augmentation 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 Solution Parameters

Items on this form are described in the table below. Table 3-14 Contact Augmentation Parameters Option

Bulk Data (field)

Description

Method

BCPARA (AUGMENT)

Defines the Normal Augmentation method, which can be set to None, Automatic, Constant or Bilinear. Automatic is a combination of Constant and Blinear where augmentation is based on constant penetration for linear elements and on a bilinear penetration for quadratic elements.

Penalty Factor

BCPARA (PENALT)

If no Penalty Factor is specified, one will be automatically determined.

Penetration Distance

BCPARA (AUGDIST)

If no Penetration Distances is specified, one will automatically determined.

Augmentation (Tangential)

BCPARA (TAUGMNT)

Turns ON the augmentation for the sticking part of friction.

Penalty Factor

BCPARA (TPENALT)

Penalty factor for sticking part of friction. Default is PENALT/1000 if not defined.

Slip Distance

BCPARA (STKSLP)

Maximum allowable slip distance for sticking, beyond which there is no sticking, only sliding.

OK

Closes the form and saves any data change on it. Note that the data is not actually saved with the job until the Apply button is pressed on the main Analysis form.

Defaults

Resets all values on the form to their defaults.

Cancel

Closes the form and discards any changes made on this form and reverts the values back to their state before the form was opened.

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Initial Contact To define initial contact, on the Contact Control Parameters... subform, select Initial Contact... or Initial Contact Pair Loadcase...

Initial Contact via Contact Table: If defining contact body interaction with a contact table, the form above appears and the form works exactly as the Contact Table form for a standard Load Step, except that a unique BCTABLE with ID 0 (zero) is written. If no specific initial contact table is specified, then the BCTABLE specified in the first load step is also written as BCTABLE with ID=0. See Contact Table, 345 for the operation of the Contact Table form. You must make some changes to the default contact table in order for a unique BCTABL1 ID=0 to be written. If all contact tables are defined using defaults, then BCONTACT=ALLBODY is written to the Case Control and no BCTABL1 entries are written.

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Chapter 3: Running an Analysis Solution Parameters

Note: Initial contact uses the contact bodies in the currently active load case, which is displayed in the title of the Initial Contact Table form. If the spreadsheet on the form shows no contact bodies, this means the current load case does not have any contact bodies associated with it. Please go to the Loads and Boundary Conditions (LBCs) application and set the active load case to one that has the appropriate contact bodies in it. Initial Contact via Contact Body Pairs: If using contact Body Pairs instead of a Contact Table, you must select the load case containing the contact Body Pairs.

The smaller form appears as shown above to allow you to select a load case. This load case must contain the contact Body Pairs that define initial contact conditions. If initial contact conditions differ from those in the first Load Step associated with the analysis job, then create additional contact body pairs and place them in a separate load case. See contact Body Pair, 262. The same number of body pairs should be place in this load case as with the standard load case associated to the Load Steps. Then this form is used to associate the load case with initial contact. There should be a one-to-one correspondence between the standard body pairs associated with the load case of the first Load Step and the ones created for initial contact.

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Note: General note on load cases and contact bodies and body pairs. Every load case used in the analysis job that is associated to a Load Step or used for initial contact should contain the exact same contact bodies. Do not leave any contact bodies out of the load cases or unintended or unanticipated results can occur. Direct

Text Input

This form is used to directly enter entries in the Nastran System Cell, File Management, Executive Control, Case Control, and bulk data sections of the MSC Nastran input file. It is most convenient to place INCLUDE statements for inclusion of externally defined bulk data. The Direct Text Input option on the Load Steps form should be used to directly enter text within a Load Step definition. See Load Step Direct Text Input, 318. Details of each widget are explained in the table below.

Table 3-15 Direct Text Input Options Option

Descriptions

XXX Section

Switches the text box view to display the text for that section the MSC Nastran input deck that is to be written.

XXX Write to Input Deck

Turns ON the writing of the text for this section of the input file.

Write at Start / End

Determines if the text is to be written at the Start or End of the section. That is written before or after the standard translation writes its data. Text entered into the Case Control section is written to the input file before the first Load Step and Subcase if set to Start and after all Load Steps if set to End.

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Chapter 3: Running an Analysis Direct Text Input

Table 3-15 Direct Text Input Options (continued) Option

Descriptions

OK

Saves the current setting and data for the four sections and closes the form. The text is not actually saved with the job until the Apply button is pressed on the Analysis 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. MSC Nastran Input File Import 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 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. 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 entries 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 entries are placed back into the input deck when it is written out again. Note that decks with large amounts of rejected entries and comments may place an unacceptable amount of data in these text boxes. You may see messages like this: 

The maximum number of Comment/Unrecognized Line import has been set to 1000.



The specified number (1000) of comments/unrecognized entities has been exceeded. Additional lines will not be imported as Direct Text Input. To modify, change the Offset/Maximum for importing comments under the Entity Selection or Input Options form using the Define Offsets...



You can also set the system environment variable DTI_LINE_LIMIT DEFAULT or include pref_env_set_integer( "patran_dti_line_limit", ) in the settings.pcl file.

See Read Input File, 282 for more details on file import.

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Load Steps This form appears when the Load Steps... button is selected on the Analysis form. A Load Step 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 SOL 400 run.

Load Steps versus Subcases In MSC Nastran, SOL 400 is unique to most other standard solution sequences in that it uses Load Steps as opposed to Subcases. However, a Subcase still needs to be defined in SOL 400. A Subcase is simply a collection of Load Cases. Thus, Subcases are not specifically created in the Implicit Nonlinear preference, only Load Steps. Multiple Subcases are allowed in SOL 400, meaning that more than one set of Load Steps can be defined. It is important to understand that each MSC Nastran SUBCASE is an independent analysis. The solution of any MSC Nastran STEP (Load Step), is a continuation of the solution from any previous STEP within that particular SUBCASE. As soon as another SUBCASE is encountered in the MSC Nastran Case Control, a new independent analysis begins that is not influenced by a previous SUBCASE or its associated STEPs. See Load Step Select, 383 for more details.

Main Index

Chapter 3: Running an Analysis Load Steps

This section deals with the actual creation/definition of a Load Step. The selection of existing Load Steps into groupings for Subcases is done on the Load Step Select, 383 form.

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Create Load Step The Load Step creation form is shown here. Each portion of the form is described in the table below.

Note: A standard set of default Load Step parameters is automatically associated to each Patran load case to create a Load Step with the same name as the load case. Thus, if you are satisfied with the default settings, it is not actually necessary to modify or create Load Steps as they already exist per the load cases created. This is true only for Analysis Type = Statics. If you need to change the Analysis Type of the Load Step, you must create or modify an existing Load Step.

Main Index

Chapter 3: Running an Analysis Load Steps

Table 3-16 Load Step Create Options Option

Descriptions

Action

Set this to Create to create a new or modify an existing Load Step. Other options are Delete (see Delete Load Step, 319) and Global Data (see Edit Load Steps, 319).

Available Steps

This lists all the available existing Load Steps that have already been created. You must select one of these to modify an existing Load Step. See the footnote at the bottom of this table.*

Step Name

The name of the Load Step. Enter this or change it to create a new Load Step. When creating multiple Load Steps, it is convenient to select a similar one from the Available Steps list box, then change the Step Name and any parameters as necessary. You must press Apply for the changes to be saved.

Available Load Cases

All Load Steps must be associated to a load case, which is the definition or collection of loads and boundary conditions applicable for the Load Step. See footnote below.

Analysis Type

Each Load Step must be associated to an analysis type. Set this accordingly. Valid types are Statics (default), Normal Modes, Buckling, Transient Dynamic, Steady State Heat, and Transient Heat. Each analysis type has a default set of parameters and output requests associated with them.You only need to change them if they are not sufficient for your needs.

Load Step Options

These buttons give access to parameters that may be modified for the Load Step. A standard set is defined for each Analysis Type and are only necessary to modify if not adequate for your analysis.

Step Parameters...

For each Analysis Type, a set of Load Step parameters can be modified from this subordinate form that appears. For a description of each of these, please see Load Step Parameters, 320.

Output Requests...

Results output requests are set on this form for the Load Step. A default set is pre-defined for each Analysis Type. To make modifications, please see Output Requests, 362.

Direct Text Input...

You may define additional MSC Nastran key words or comments to be placed directly inside the input deck in the SUBCASE/STEP section with this capability. See Load Step Direct Text Input, 318.

Apply

Press Apply to create or modify the Load Step and save it in the database. Note that the act of creating a Load Step does not associate it to an analysis job. That is done in Load Step Select, 383.

Cancel Closes the form without creating or modify the Load Step. *Load Steps versus Load Cases: Load cases are created in the Load Cases application of Patran and consist of simply a collection of loads and boundary conditions. A load case must be associated to a Load Step. That is the Load Step is a collection of parameters plus the loads and boundary conditions for that particular Load Step of the analysis. For ease-of-use purposes, when a load case is created, a Load Step by the same name also appears in this form with the that load case associated to it. If you are satisfied using the default parameters of the Load Step, it is not necessary to modify the Load Step.

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Load Step Direct Text Input This form is used to directly enter text (MSC Nastran keywords or comment lines) into the Case Control section for the defined Load Step. Each option is described in the table below.

Table 3-17 Options for Load Step Direct Text Input Option

Descriptions

Write to Input Deck

Turn this toggle ON to actually have the text written to the input deck. If the toggle os OFF, the text is still saved with the Load Step but not written to the input deck.

Write at Start of Step Write at End of Step

The text is written as either the first text directly after the STEP key word or after all Load Step parameters are written, but before the next STEP, SUBCASE, or CEND statement.

Text Area

Enter the text in this area as you wish it to appear in the input deck for this Load Step.

OK

Saves the text and form settings and closes the form. Note that this information is not saved with the Load Step in the database until the Apply button is pressed on the Load Step form with the Action set to Create.

Clear

Clears the text area of all text.

Reset

Resets the form and text area back to what it was when the form was first opened.

Cancel

Closes and resets the form and text back to what it was before it was opened.

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Chapter 3: Running an Analysis Load Steps

Delete Load Step To delete one or more load steps: 1. select Load Steps... from the Analysis form, and set the Action to Delete. 2. Select the desired to Load Steps to delete from the list. 3. Press the Apply button.

Note: You cannot delete Load Steps that are associated with existing analysis jobs. You must first disassociate the Load Step from its job by either going to the Analysis form and deleting the job (see Access Results, 280) or removing the Load Step from the selected Load Steps for the analysis job (see Load Step Select, 383) and then saving the job by pressing Apply on the Analysis form with the Action set to Analyze and the Method set to Analysis Deck (if you do not want to actually submit the job for analysis).

Edit Load Steps Global Data is the Action for editing output requests of one or more Load Steps simultaneously. Only output requests can be modified globally. To accomplish this, simply select the Load Steps of interest in the list and

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then click on the Output Requests... button. A form appears to allow changes to be made. When you are satisfied with the changes, press the Apply button to recreate all the Load Steps.

Use the Output Requests... button to edit the output requests associated with the selected Load Steps. The Edit Output Request form appears. See Edit Output Requests, 375 for a description of how this form works.

Load Step Parameters The type of analysis can be changed for each Load Step. To specify this change, the Load Steps form includes an Analysis Type pull-down menu with options for Static, Normal Modes, Buckling, Transient Dynamic, Steady State Heat, and Transient Heat analyses. In turn, specifying the Load Step parameters is dependent

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Chapter 3: Running an Analysis Load Step Parameters

on the analysis type selected for the Load Step. The following sections define the load step parameters for each analysis type.

On the Load Step form, set the Analysis Type, then click on the Step Parameters... button to open the appropriate form for the analysis type. A description of each follows.

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Static Parameters This subform defines the parameters for a static Load Step.

Parameters on this form are explained in the table below.. Table 3-18 Static Analysis Step Parameters & Options Option

Case Control or Bulk Data

Linearity Nonlinear: ANALYSIS=NLSTATIC Linear: ANALYSIS=STATIC

Description Prescribes the linearity effects for the load step. Valid selections are Nonlinear (default) or Linear. Widgets are enabled or disabled on this form dependent on this setting.

Creep

NLSTEP (“GENERAL” CREEP) If ON, sets NLSTEP “GENERAL” CREEP field to 1 for creep analysis. For more information about Implicit Creep Options, see Solution Parameters, Elastoplastic Material Properties (Yield Function), Viscoplastic Material Properties, and Adaptive Load Incrementation Criteria.

Solvers/Options

Opens the form for defining MSC Nastran solver options for the Load Step. See Solvers/Options, 334.

Load Increment Params...

Opens the form to define load increment parameters. They are described in Load Increment Parameters, 337.

Iteration Params...

Opens the form to set the iterative procedures that are employed to solve the equilibrium problem at each load increment. They are described in Iteration Parameters, 342.

Contact Table...

Opens the form to define a contact interaction via a contact table. This is described in Contact Table, 345. If this button is not visible, check the Use Contact Table(s) toggle on the Contact Control Parameters, 302 form accessible from the Solution Parameters, 298 form.

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Chapter 3: Running an Analysis Load Step Parameters

323

Table 3-18 Static Analysis Step Parameters & Options Option

Case Control or Bulk Data

Description

Brake Squeal Parameters

Opens the form for defining parameter values for modeling brake squeal for the Load Step. See Brake Squeal Parameters, 356.

OK

Closes the form and saves any settings. You must press the Apply button on the Load Steps form for the parameters to actually be saved in the database for this Load Step.

Defaults

Returns the form to its default settings.

Cancel

Closes the form and restores any settings to its previous state before the form was opened.

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Normal Modes Parameters This subform defines the parameters for a normal modes Load Step. ANALYSIS=MODES is written to the Case Control for this Load Step type.

Parameters on this form are explained in the table below.

Table 3-19 Normal Modes Analysis Step Parameters & Options Option

Bulk Data (fields)

Extraction Method Lanczos: EIGRL Inverse Power: EIGR

Description Defines the method to use to extract the real eigenvalues. This parameter can be set to Lanczos or Inverse Power. If this is set to Lanczos, this indicates that an EIGRL Bulk Data entry is created. Otherwise, this defines the setting of the METHOD field on the EIGR Bulk Data entry.

Lanczos Parameters EIGRL Lower and Upper Frequencies

EIGRL (V1 & V2)

Define the lower and upper limits to the range of frequencies to be examined. Can be left blank.

Desired # of Roots

EIGRL (ND)

Number of roots desired. Default is 10.

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Chapter 3: Running an Analysis Load Step Parameters

Table 3-19 Normal Modes Analysis Step Parameters & Options Option

Bulk Data (fields)

Description

Diagnostic Output Level

EIGRL (MSGLVL)

Defines the level of desired output. This can take any integer value between 0 (default) and 3.

Normalization Method

EIGRL( NORM)

Indicates what type of eigenvalue normalization is to be done. This parameter can be set to either: Mass or Maximum. Inverse Power Parameters EIGR (METHOD=INV)

Lower and Upper Frequencies

EIGR (F1 & F2)

Define the lower and upper limits to the range of frequencies to be examined.

Estimated # of Roots

EIGR (NE)

Estimate of number of roots in frequency range. Default is 100.

Desired # of Roots

EIGR (ND)

Number of roots desired. Default is 10.

Normalization Method

EIGR (NORM)

Indicates what type of eigenvalue normalization is to be done. This parameter can be set to either: Mass or Maximum or Point.

Normalization Point

EIGR (G)

Node identification number required when Normalization Method is Point.

Normalization Component

EIGR (C)

Defines the degree-of-freedom component at the Normalization Point to be used and is required for this option. Valid entries are 1, 2, 3, 4, 5, or 6.

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Table 3-19 Normal Modes Analysis Step Parameters & Options Option

Bulk Data (fields)

Description General Parameters

Contact Table... Opens the form to define a contact interaction via a contact table. This is described in Contact Table, 345. If this button is not visible, check the Use Contact Table(s) toggle on the Contact Control Parameters, 302 form accessible from the Solution Parameters, 298 form. OK

Closes the form and saves any settings. You must press the Apply button on the Load Steps form for the parameters to actually be saved in the database for this Load Step.

Defaults

Returns the form to its default settings.

Cancel

Closes the form and restores any settings to its previous state before the form was opened.

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Chapter 3: Running an Analysis Load Step Parameters

Buckling Parameters This subform defines the parameters for a normal modes Load Step. ANALYSIS=BUCK is written to the Case Control for this Load Step type.

In SOL 400 a Buckling Load Step is based upon a linear buckling analysis based upon the initial undeformed geometry. Parameters on this form are explained in the table below.

Table 3-20 Buckling Analysis Step Parameters & Options Option

Bulk Data (fields)

Extraction Method Lanczos: EIGRL Inverse Power: EIGB

Description Defines the method to use to extract the real eigenvalues. This parameter can be set to Lanczos or Inverse Power. If this is set to Lanczos, this indicates that an EIGRL Bulk Data entry is created. Otherwise, this defines the setting of the METHOD field on the EIGR Bulk Data entry.

Lanczos Parameters EIGRL Lower and Upper Frequencies

EIGRL (V1 & V2)

Define the lower and upper limits to the range of frequencies to be examined. Can be left blank.

Desired # of Roots

EIGRL (ND)

Number of roots desired. Default is 10.

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Table 3-20 Buckling Analysis Step Parameters & Options Option

Bulk Data (fields)

Description

Diagnostic Output Level

EIGRL (MSGLVL)

Defines the level of desired output. This can take any integer value between 0 (default) and 3.

Normalization Method

EIGRL( NORM)

Indicates what type of eigenvalue normalization is to be done. This parameter can be set to either. This is not actually written since the only valid option for buckling analysis is Maximum. Inverse Power Parameters EIGB (METHOD=INV)

Lower and Upper Frequencies

EIGR (L1 & L2)

Define the lower and upper limits to the range of frequencies to be examined.

Estimated # of Roots

EIGB (NEP)

Estimate of number of roots in frequency range. Default is 100.

Desired # of Positive Roots Negative Roots

EIGB (NDP/NDN)

Number of positive and negative roots desired. Default is 1. Enter 3*NEP to use the MSC Nastran default.

Normalization Method

EIGB (NORM)

Indicates what type of eigenvalue normalization is to be done. This parameter can be set to either: Maximum or Point.

Normalization Point

EIGB (G)

Node identification number required when Normalization Method is Point.

Normalization Component

EIGB (C)

Defines the degree-of-freedom component at the Normalization Point to be used and is required for this option. Valid entries are 1, 2, 3, 4, 5, or 6.

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Chapter 3: Running an Analysis Load Step Parameters

Table 3-20 Buckling Analysis Step Parameters & Options Option

Bulk Data (fields)

Description General Parameters

Contact Table... Opens the form to define a contact interaction via a contact table. This is described in Contact Table, 345. If this button is not visible, check the Use Contact Table(s) toggle on the Contact Control Parameters, 302 form accessible from the Solution Parameters, 298 form. OK

Closes the form and saves any settings. You must press the Apply button on the Load Steps form for the parameters to actually be saved in the database for this Load Step.

Defaults

Returns the form to its default settings.

Cancel

Closes the form and restores any settings to its previous state before the form was opened.

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Transient Dynamic Parameters This subform defines the parameters for a transient dynamic Load Step.

Parameters on this form are explained in the table below.

Table 3-21 Transient Dynamic Step Parameters & Options Option

Case Control or Bulk Data

Linearity Nonlinear: ANALYSIS=NLTRAN

Description Prescribes the linearity effects for the load step. Options are: Nonlinear and Linear.

Linear: ANALYSIS=MTRAN Time Integration Method

Time integration scheme to use in dynamic analysis. Only Direct is valid for Nonlinear while only Modal is valid for Linear currently.

Load Increment Opens the form to define load increment parameters. They are described in Load Increment Parameters, Params... 337. Iteration Params...

Opens the form to set the iterative procedures that are employed to solve the equilibrium problem at each load increment. They are described in Iteration Parameters, 342.

Contact Table... Opens the form to define a contact interaction via a contact table. This is described in Contact Table, 345. If this button is not visible, check the Use Contact Table(s) toggle on the Contact Control Parameters, 302 form accessible from the Solution Parameters, 298 form. Eigenvalue Extraction

Opens the form for defining the eigenvalue extraction controls. See Real Eigenvalue Extraction, 358.

Define Time Step...

Opens the form to define TSTEP entry. See Define Time Step, 360.

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Chapter 3: Running an Analysis Load Step Parameters

Table 3-21 Transient Dynamic Step Parameters & Options Option

Case Control or Bulk Data

Description

Define Modal Damping...

Opens the form to define Modal Damping parameters. See Define Damping, 361.

OK

Closes the form and saves any settings. You must press the Apply button on the Load Steps form for the parameters to actually be saved in the database for this Load Step.

Defaults

Returns the form to its default settings.

Cancel

Closes the form and restores any settings to its previous state before the form was opened.

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Steady State Heat Parameters This subform defines the parameters for a steady state heat transfer Load Step.

Parameters on this form are explained in the table below. Table 3-22 Steady State Heat Analysis Step Parameters & Options Case Control or Bulk Data

Description

Due to Plasticity

NLSTEP (“COUP”, HGENPLAS)

Conversion factor for heat generated due to plasticity. Default = 0.0. This is used in thermal-structural coupling analysis only.

Due to Friction

NLSTEP (“COUP”, HGENFRIC)

Conversion factor for heat generated due to friction. Default =0.0. This is used in thermal-structural coupling analysis only.

Option

Load Increment Opens the form to define load increment parameters. They are described in Load Increment Parameters, Params... 337. Iteration Params...

Opens the form to set the iterative procedures that are employed to solve the equilibrium problem at each load increment. They are described in Iteration Parameters, 342.

Contact Table... Opens the form to define a contact interaction via a contact table. This is described in Contact Table, 345. If this button is not visible, check the Use Contact Table(s) toggle on the Contact Control Parameters, 302 form accessible from the Solution Parameters, 298 form. OK

Closes the form and saves any settings. You must press the Apply button on the Load Steps form for the parameters to actually be saved in the database for this Load Step.

Defaults

Returns the form to its default settings.

Cancel

Closes the form and restores any settings to its previous state before the form was opened.

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Chapter 3: Running an Analysis Load Step Parameters

Transient Heat Parameters This subform defines the parameters for a transient heat transfer Load Step.

Parameters on this form are explained in the table below. Table 3-23 Transient Heat Analysis Step Parameters & Options Case Control or Bulk Data

Description

Due to Plasticity

NLSTEP (“COUP”, HGENPLAS)

Conversion factor for heat generated due to plasticity. Default = 0.0. This is used in thermal-structural coupling analysis only.

Due to Friction

NLSTEP (“COUP”, HGENFRIC)

Conversion factor for heat generated due to friction. Default =0.0. This is used in thermal-structural coupling analysis only.

Option

Load Increment Opens the form to define load increment parameters. They are described in Load Increment Parameters, Params... 337. Iteration Params...

Opens the form to set the iterative procedures that are employed to solve the equilibrium problem at each load increment. They are described in Iteration Parameters, 342.

Contact Table... Opens the form to define a contact interaction via a contact table. This is described in Contact Table, 345. If this button is not visible, check the Use Contact Table(s) toggle on the Contact Control Parameters, 302 form accessible from the Solution Parameters, 298 form. OK

Closes the form and saves any settings. You must press the Apply button on the Load Steps form for the parameters to actually be saved in the database for this Load Step.

Defaults

Returns the form to its default settings.

Cancel

Closes the form and restores any settings to its previous state before the form was opened.

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Solvers/Options In general, this form is used to select the MSC 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 the user interface. If a solution does not support a solver option, that option is not presented in the form or menus.

Each parameter is explained in the table below.

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Chapter 3: Running an Analysis Load Step Parameters

Table 3-24 Solver Options and Parameters Option

Case Control Bulk Data (Field)

Solver Type

Description Options are: Nastran Default: No SMETHOD or ITER entries are written. Nastran uses whatever solver is the default for the solution being used.

Iterative Element-Based (CASI): An SMETHOD case control with the SMETHOD =ELEMENT entry ELEMENT is used which invokes the iterative CASI (elementbased) 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.

SMETHOD=n ITER

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. Iterative (Customized) Parameters

Preconditioner

ITER PRECOND=

Four preconditioners are available: Jacobi, Cholesky, Cholesky/Jacobi, and CASI. The CASI is the element-based iterative solver. See the table above. All other preconditioners are 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 MSC Nastran Quick Reference Guide for more details as to which defaults are used for each solution type.

Maximum Number of Iterations

ITER ITSMAX=

Leave this blank to accept the default. Otherwise specify the maximum number of iterations allowed.

Diagonal Scaling

ITER PRECOND=

Turn ON for Jacobi and Cholesky preconditioners to allow diagonal scaling (JS or CS).

Reduced

ITER PRECOND=

Turn ON to invoke the reduced incomplete Cholesky preconditioner as opposed to just the incomplete Cholesky. This can be combined with or without diagonal scaling (RIC, RICS).

Block

ITER PRECOND=

Turn ON to invoke the block incomplete Cholesky preconditioner. You must specify Real/Complex also (BIC, BICCMPLX).

Real / Complex

ITER PRECOND=

This is only used for the block incomplete Cholesky preconditioner (BIC or BICCMPLX).

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Table 3-24 Solver Options and Parameters Option

Case Control Bulk Data (Field)

Description

Padding

ITER IPAD =

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. Must be an integer > 0.

Extraction

ITER IEXT=

Specify the extraction level for reduced or block incomplete Cholesky preconditioner. The default is zero. Must be an integer 0 through 7.

Geometric Progression

ITER CONV=

Turn ON if you wish to use geometric progression convergence criterion.

Epsilon

ITER ITSEPS=

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

ITER MSGFLG=

OFF by default. Turn ON if you want more diagnostics for each iteration. Otherwise only minimal messaging is given.

Terminate Early ITER (Resource PREFONLY= Estimate Only)

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Turn this toggle ON if you want the run to terminate with only a resource estimation.

Chapter 3: Running an Analysis Load Step Parameters

Load Increment Parameters Load and time step incrementation parameters for Static, Transient Dynamic, Steady State Heat, and Transient Heat appear on this subordinate form

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Note: If a default value is used, it generally is not written to the MSC Nastran input deck and the field is left blank. The Load Increment Parameters form differs depending on your designation of a Fixed, Adaptive, or Arclength increment type. Each parameter of the NLSTEP entry is explained in the table below. Table 3-25 Load Step Incrementation Parameters & Options Option

Bulk Data (Field)

Description Fixed Increment Parameters

Analysis Pref

NLSTEP (CTRLDEF)

Control parameter. Set to Default, QLINEAR, MILDLY, SEVERELY. The user is referred to the MSC Nastran documentation for an explanation of these settings. Using the default setting flags MSC Nastran to use its default.

Number of Increments

NLSTEP (“FIXED”, NINC)

Number of increments for fixed time stepping. The time step of each increment will be TOTTIME/NINC. Default is set to 50.

Total Time

NLSTEP (TOTTIME)

Total time for the Load Step.

Output Interval NLSTEP (“FIXED”, NO)

Interval for output. Every NO-th increment is saved for output. Default is 1. Adaptive Increment Parameters

Analysis Pref

NLSTEP (CTRLDEF)

See same parameter in Fixed increment section above

Trial Time Step Size

NLSTEP (“ADAPT”, DTINITF)

Defines the initial time step size. Default is 1% of Total Time if left blank. Value placed in field DTINITF is value given here divided by Totat Time.

Time Step Scale NLSTEP Factor (“ADAPT”, SFACT)

Indicates load will be allowed to be scaled up by this amount each increment if possible. Default is 1.2, meaning a 20% increase in load each increment if possible.

Minimum Time NLSTEP Step (“ADAPT”, DTMINF)

Indicates the smallest time step that can be used. Default is Trial Time Step / 1000 if left blank. Value placed in field DTMINF is value given here divided by Total Time.

Maximum Time Step

NLSTEP (“ADAPT”, DTMAXF)

Indicates the largest time step that can be used. Default is Total Time / 2 if left blank. Value placed in field DTMAXF is value given here divided by Total Time.

Maximum # of Steps

NLSTEP (“ADAPT”, NSMAX)

Maximum number of increments. The job will stop if this limit is reached.

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Chapter 3: Running an Analysis Load Step Parameters

Table 3-25 Load Step Incrementation Parameters & Options Option # of Steps of Output

Artificial Damping

Bulk Data (Field) NLSTEP (“ADAPT”, INTOUT)

NLSTEP (“ADAPT”, IDAMP)

Description Output flag INTOUT > -1. (Default = 0) -1

Only the last increment of the step will be output.

0

Every computed load increment will be output.

>0

The output will be obtained at INTOUT equally spaced intervals. The time step will be temporarily adjusted if necessary in order to reach these points in time.

Flag for activating artificial damping for static analysis. None - 0 for not adding damping. This is default. Using Damping - 4 for time step control using damping. Damping Based - 5 for damping based time step control but no damping added. Adding Damping - 6 for adding damping when the minimum time step has been reached. For nonlinear analysis with advanced element, it is recommended to select 6 for robust and stable analysis.

Damping Ratio

NLSTEP (“ADAPT”, DAMP)

Criteria

Multiple adaptive load stepping criteria is available. By default, none is necessary to be defined. These criteria are described below in Adaptive Load Incrementation Criteria, 340.

Damping Ratio.

Arclength Increment Parameters (Static analysis only - not to be used with contact) Analysis Pref

NLSTEP (CTRLDEF)

See same parameter in Fixed increment section above

Arclength Method

NLSTEP (“ARCLN”, TYPE)

Constraint type. The available options are Crisfield (CRIS), Riks/Ramm (RIKS), and Modified Riks/Ramm (MRIKS).

Trial Time Step Size

NLSTEP (“ARCLN”, TYPE)

Initial time step for the arclength procedure. The value place in the TYPE field is a fraction of the totat time of the Load Step defined by the value given here divided by Total Time.

Max Ratio Arc Length/Initial Arc Length

NLSTEP (“ARCLN”, MAXALR)

Maximum allowable arc-length adjustment ratio between increments for the adaptive arc-length method. Must be a value greater than 1.0. Default = 4.0.

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Table 3-25 Load Step Incrementation Parameters & Options Bulk Data (Field)

Option

Description

Min Ratio Arc Length/Initial Arc Length

NLSTEP (“ARCLN”, MINALR)

Minimum allowable arc-length adjustment ratio between increments for the adaptive arc-length method..Should be number between zero and 1.0. Default = 0.25.

Scale Factor

NLSTEP (“ARCLN”, SFACTA)

Indicates load will be allowed to be scaled up by this amount each increment if possible. Default is 0.0 - this parameter is typically not used and is left blank if default is supplied.

Desired # of Increments

NLSTEP (“ARCLN”, NDESIRA)

Desired number of iterations for convergence. Default = 4.

Max # of Increments

NLSTEP (“ARCLN”, NSMAXA)

Maximum number of increments in the current load case. The job will stop if this limit is reached.

Total Time

NLSTEP (TOTTIME)

Total time for the Load Step.

Adaptive Load Incrementation Criteria Parameters on this form are written to the MSC Nastran NLSTEP entry, when defining Adaptive load incrementation and to the TABSCTL entry for SOL 400, which are referenced from the NLSTEP entry

Each parameter of the is explained in the table below.

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Chapter 3: Running an Analysis Load Step Parameters

Table 3-26 Load Step Physical Criteria Parameters & Options Bulk Data (Field)

Option

Description

Treat Criteria as:

NLSTEP (“ADAPT”, LIMTAR)

Treat criteria as Limits or Targets.

Use Automatic Criteria Continue if not Satisfied

NLSTEP (“ADAPT”, IPHYS)

Uses automatic physical criteria if top toggle is ON. Bottom toggle defines what happens if the criteria is not met. Both are OFF by default.

Ratio Between Steps:

NLSTEP (“ADAPT”, RSMALL, RBIG)

Defines the [Smallest] and [Largest] ratios acceptable between load increments. For Smallest, default = 0.1, For Largest, default=10.0.

Increment Criteria

TABSCTL (ICRIT_i)

Selects the type of criteria to be used.The labels XXX Range and Increment Allowed change based on the Increment Criteria selected.

Use Criterion

For a criteria to be used, this toggle must be turned ON for the criterion in question. Ensure that you check each criterion in turn.

Criterion Range TABSCTL (MTi_j)

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.

Increment Allowed

TABSCTL (YTi_j)

The “Criterion” title changes according to the Increment Criteria chosen.

Select a Group (Optional)

TABSCTL (SET3_IDi)

You can optionally select a group of elements to which this criterion is to be applied. No group is selected by default and the criterion is applied to all element. A SET3 is written to define the elements if a group is supplied.

SET3

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Iteration Parameters This subordinate form appears when the Step Parameters... / Iteration Parameters... button is selected for Static, Transient Dynamic, Steady State, and Transient Heat Load Steps. Mechanical Heat Transfer

Main Index

Chapter 3: Running an Analysis Load Step Parameters

Each parameter of the is explained in the table below. Generally default values are not written out and are left as blank fields in the input deck. Table 3-27 Load Step Physical Criteria Parameters & Options Option

Bulk Data (Field)

Description

Min # of Iterations per Increment

NLSTEP (“GENERAL”, MINITER)

Specify the fewest number of iterations per load increment. Default = 1.

Max # of Iterations per Increment

NLSTEP (“GENERAL”, MAXITER)

Specify the largest number of iterations per load increment. Default = 10.

Desired # of Iterations per Increment

NLSTEP (“ADAPT”, NDESIR) (“ARCLN”, NDESIRA)

Desired number of iterations per increment. Default = 4.

Number of Iterations per Update

NLSTEP (“MECH”, KSTEP) (“HEAT”, KSTEPH)

Specify the allowable number of iterations per stiffness matrix update. Default = 10.

Matrix Update Method

NLSTEP (“MECH”, KMETHOD) (“HEAT”, KMETHODH)

This is the method for controlling stiffness updates. Choices are: 1) Automatic (automatically selects the most efficient strategy based on convergence rates - available for heat transfer only) 2) Controlled Iters. updates the matrix at every KSTEP iterations and at convergence if KSTEP Second - Blanks the lower triangular section of the table matrix such that no input can be accepted. Only the contact bodies from the upper portion are written, which forces the contact check of the first body (the one higher in the contact table) with respect to the second body.



Second-> 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.

Touch All

Places a T to indicate touching status for all deformable-deformable or rigid-deformable bodies.

Glue All

Places a G to indicate glued status for all deformable-deformable or rigid-deformable bodies.

Deactivate All

Blanks the spreadsheet cells - indicating no contact interaction.

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Chapter 3: Running an Analysis Load Step Parameters

Table 3-28 Contact Table Parameters & Options Bulk Data (Field)

Option

Description

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 from other Load Steps.

OK

Closes the Contact Table form and saves the data. Note that the Apply button must be pressed on the Load Steps form in order for the Contact Table to actually be saved as part of the Load Step and saved to the database.

Defaults

Resets the Contact Table and all body pair settings/parameters to their defaults. See the discussion about Default Contact Table above.

Cancel

Closes the form and does not save any changes made while the form was open.

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 Load Step. The forces associated with this body can be removed immediately in the first increment or gradually over the time of the entire Load Step with the Force Removal switch described below.

Contact Matrix

The rows correspond to Touching Body (Slave). The columns correspond to Touched Body (Master). 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 (Slave) Touched Body (Master)

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. General Properties (for data boxes you must press the Enter or Return key for the data to be accepted) (any global settings are overridden by these settings per body pair)

Distance Tolerance

BCONPRG ERROR=

Set the Distance Tolerance for this pair of contact bodies.

Bias Factor

BCONPRG BIAS=

Bias the domain defined by the distance tolerance. Must be a number between 0.0 and 1.0.

Force Removal

BCMOVE (MTYPE= RELEASE, IREL)

Select 1) Immediate, or 2) Gradual. This is activated when a body is set to Release by toggling that cell to Y.. For example, set to Release by clicking once on the corresponding Release cell, then clicking once again to change from N to Y. The entry BCMOVE is written to the input file. Only the Contact Table can be used to write BCMOVE.

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Table 3-28 Contact Table Parameters & Options Bulk Data (Field)

Option

Description

Contact Detection

BCONPRG ISEARCH=

Select 1) Automatic, 2) Double Sided, 3) 1st->2nd, or 4) 2nd->1st. If none are selected Default(by body #) is used. Not applicable for Segment to Segment contact.

Retain Gaps/Overlaps

BCONPRG IGLUE=

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

BCONPRG ICOORD=

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

BCONPRG ICOORD=

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 deformabledeformable contact only.

Allow Separation

BCONPRG JGLUE=

Allows separation of a node if ON based on whether a Separation Threshold has been set or Breaking Glue parameters are set.

Retain Moment BCONPRG IGLUE=

Insures full moment carrying glue when shells contact.

Contact Boundary...

BCONPRG COPTS=, COPTM=

See Contact Boundary Option Parameters, 354

Advanced...

See Advanced Contact Parameters, 352 Analysis Properties - Structural

Separation Threshold

BCONPRP FNTOL=

Specify a Separation 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.

Friction Coefficient

BCONPRP FRIC=

Set the Friction Coefficient for this pair of contact bodies.

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Chapter 3: Running an Analysis Load Step Parameters

Table 3-28 Contact Table Parameters & Options Bulk Data (Field)

Option

Description

Interference Closure

BCONPRG CINTERF=

Set the Interference Closure for this pair of contact bodies.

Friction Stress Limit

BCONPRP FRLIM=

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

BCONPRG SLIDE=

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.

Hard-Soft Ratio BCONPRG HARDS=

Hard-Soft Ratio. Only used if double-sided contact with automatic constraint optimization. Analysis Properties - Thermal

Near Contact Distance Tolerance

BCONPRP DQNEAR=

Distance below which near thermal contact behavior occurs.

Heat Transfer Coefficient

BCONPRP HCT=

Set the Heat Transfer Coefficient for this pair of contact bodies.

Near Contact HT Coeff.

BCONPRP HCV=

Convection coefficient for near field behavior. Can reference a temperature dependent non-spatial field.

Natural Convection Coeff.

BCONPRP HNC=

Natural convection coefficient for near field behavior. Can reference a temperature dependent non-spatial field.

Natural Convection Exponent

BCONPRP BNC=

Exponent associated with the natural convection coefficient for near field behavior. Can reference a temperature dependent non-spatial field.

Surface Emissivity

BCONPRP EMISS=

Emissivity for radiation to the environment for near thermal radiation. Can reference a temperature dependent non-spatial field.

Distance Dep. Conv. Coeff.

BCONPRP HBL=

Separation distance dependent thermal convection coefficient. Can reference a temperature dependent nonspatial field.

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Advanced Contact Parameters 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 contact pair. You must open and repeat this operation for each pair you for which you wish to defined these properties.

Each item of this form is explained in the table below. Table 3-29 Advanced Contact Table (body pair) Parameters Option

Bulk Data (Field)

Description

Breaking Glue - Turn ON to activate if glued contact (G in the Contact Table matrix cell) Max Normal Stress

BCONPRP BGSN=

The maximum normal stress that will cause the glued contact to become un-glued.

Max Tangential Stress

BCONPRP BGST=

The maximum tangential stress that will cause the glued contact to become un-glued.

First Exponent

BCONPRP BGM=

The exponent of the tangential stress term (BGM) in the following equation:  sigman --------------------  BGSN 

Second Exponent

BCONPRP BGN=

sigmat +  ------------------  BGST 

BGM

> 1.0

The exponent of the normal stress term (BGN) in the following equation:  sigman --------------------  BGSN 

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BGN

BGN

sigmat BGM +  ------------------ > 1.0  BGST 

Chapter 3: Running an Analysis Load Step Parameters

Table 3-29 Advanced Contact Table (body pair) Parameters Option

Bulk Data (Field)

Description

Segment-to-Segment Contact Normal Penalty Factor

BCONPRP PENALT=

The augmented lagrange penalty factor used by the segment-to-segment contact algorithm.

Penetration Distance

BCONPRP AUGDIST=

The penetration distance beyond which the augmentation will be applied as used by the segment-to-segment contact algorithm.

Tangential Penalty Factor

BCONPRP TPENALT=

Augmented Lagrange penalty factor for sticking part of friction. The default is PENALT/1000 if left blank, where PENALT parameter is the Augmented Lagrange penalty factor for normal contact.

Slip Distance

BCONPRP STKSLP=

Maximum allowable slip distance for sticking, beyond it there is no sticking, only sliding exists.

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Contact Boundary Option Parameters This form helps define contact boundary option. The COPTS and COPTM fields on the BCONPRG entry are set accordingly.

Each item of this form is explained in the table below. There is a setting each for the SLAVE and the MASTER contact body for each contact pair. Table 3-30 Contact Boundary Option (body pair) Parameters Option

Bulk Data (Field)

Description

Check Layers

BCONPRG COPTS/COPTM=

For contact bodies composed of shell elements, this option menu chooses the layers to be checked. Available options are: Top and Bottom (B=1), Top Only (B=4), Bottom Only (B=2). Check Layers and Ignore Thickness combination enters the appropriate value in equation below for variable B.

Ignore Thickness

BCONPRG COPTS/COPTM=

Turn this button ON to ignore shell thickness. Contact will not be detected until the mid surface of the shell is encountered. Check Layers and Ignore Thickness combination enters the appropriate value in equation below for variable B. If this is ON, B = 6, 5, and 3 for the Check Layers options, respectively, as opposed to the values given above.

Include Edges

BCONPRG COPTS/COPTM=

Use this to detect contact of edges. There are three options, Beam/Bar (C=1), Free and Hard Shell (B=10), or Both (B=11). This enters the appropriate value in equation below for variable C. For Segment-to-Segment contact, this is automatic.

For COPTM/COPTS parameters, the formula COPTx=A+10*B+1000*C is used. The default is 1011.

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Chapter 3: Running an Analysis Load Step Parameters

Main Index



A is always 1 and defines that the outside or solid elements are to be included in the contact description.



B is defined by shell element contact interaction as explained above. B is always 1 for rigid surfaces.



C is for defining edge contact descriptions and has no effect if beam-to-beam contact has not been turned on under Contact Detection, 305 and is ignored for segment to segment contact.

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Brake Squeal Parameters Defines parameter values for modeling brake squeal. This is not applicable or available when using Segmentto-Segment contact.

Each item of this form is explained in the table below. A BSQUEAL Case Control is written for the Load Step when this is activated. Table 3-31 Brake Squeal Parameters Option

Case Control Bulk Data (Field)

Description

Enable Brake Squeal

BSQUEAL=

Brake Squeal is activated when this check box is selected.

Load Factor

BSQUEAL (OMETH)

Defines the load factor for which the brake squeal analysis is to be performed.

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Chapter 3: Running an Analysis Load Step Parameters

Table 3-31 Brake Squeal Parameters Option

Case Control Bulk Data (Field)

Description

Average Stiffness

BSQUEAL (AVSTIF)

Approximate average stiffness per unit area between the brake pads and disk. This parameter is used as a penalty contact stiffness for brake 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.

Brake Squeal Only

BSQUEAL (BSONLY)

This is used to specify whether or not the nonlinear analysis will be continued after the brake squeal event. If this is selected, the nonlinear iterations will cease immediately after the event, otherwise the nonlinear iterations will be continued. OFF by default.

Axis of Rotation Vector

BSQUEAL (RX,RY,RZ)

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

BSQUEAL (X,Y,Z)

These are the coordinates of a point on the axis of rotation, [X,Y,Z]. The coordinates are in the basic coordinate system.

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Real Eigenvalue Extraction Provides real eigenvalue extraction data and parameters for modal transient analysis load steps when the Linearity is set to Linear on the Transient Dynamic Parameters form.

Table 3-32 Real Eigenvalue Extraction Option

Bulk Data (fields)

Extraction Method Lanczos: EIGRL Inverse Power: EIGR

Description Defines the method to use to extract the real eigenvalues. This parameter can be set to Lanczos or Inverse Power. If this is set to Lanczos, this indicates that an EIGRL Bulk Data entry is created. Otherwise, this defines the setting of the METHOD field on the EIGR Bulk Data entry.

Lanczos Parameters EIGRL Lower and Upper Frequencies

EIGRL (V1 & V2)

Define the lower and upper limits to the range of frequencies to be examined. Can be left blank.

Desired # of Roots

EIGRL (ND)

Number of roots desired. Default is 10.

Diagnostic Output Level

EIGRL (MSGLVL)

Defines the level of desired output. This can take any integer value between 0 (default) and 3.

Main Index

Chapter 3: Running an Analysis Load Step Parameters

Table 3-32 Real Eigenvalue Extraction Option Normalization Method

Bulk Data (fields) EIGRL( NORM)

Description Indicates what type of eigenvalue normalization is to be done. This parameter can be set to either: Mass or Maximum. Inverse Power Parameters EIGR (METHOD=INV)

Lower and Upper Frequencies

EIGR (F1 & F2)

Define the lower and upper limits to the range of frequencies to be examined.

Estimated # of Roots

EIGR (NE)

Estimate of number of roots in frequency range. Default is 100.

Desired # of Roots

EIGR (ND)

Number of roots desired. Default is 10.

Normalization Method

EIGR (NORM)

Indicates what type of eigenvalue normalization is to be done. This parameter can be set to either: Mass or Maximum or Point.

Normalization Point

EIGR (G)

Node identification number required when Normalization Method is Point.

Normalization Component

EIGR (C)

Defines the degree-of-freedom component at the Normalization Point to be used and is required for this option. Valid entries are 1, 2, 3, 4, 5, or 6.

OK

Closes the form and saves any settings. You must press the Apply button on the Load Steps form for the parameters to actually be saved in the database for this Load Step.

Defaults

Returns the form to its default settings.

Cancel

Closes the form and restores any settings to its previous state before the form was opened.

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Define Time Step Provides time stepping definition for modal transient analysis load steps when the Linearity is set to Linear on the Transient Dynamic Parameters form.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.

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Chapter 3: Running an Analysis Load Step Parameters

Define Damping Provides damping definition for modal transient analysis load steps when the Linearity is set to Linear on the Transient Dynamic Parameters form. 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.

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Table 3-33 Damping Parameters Option

Bulk Data (fields)

Description

Modal Damping

TABDMP1

Defines modal damping as a tabular function of natural frequency. Type of damping units, Character: “G”, “CRIT”, or “Q”. Default is “G”.

Frequency

TABDMP1(fi)

Frequency for modal damping.

Value

TABDMP1(gi)

Damping value.

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.

Clear All

Clears all data from the spreadsheet.

Delete Row

Deletes the selected row.

Create a Field

To create a Field for the damping data, click in the Create a Field check box.

Load Data from To bring in damping data from an existing Field, click on the Load Data From Field button, then select Field... the Field. OK

Closes the form and saves any settings. You must press the Apply button on the Load Steps form for the parameters to actually be saved in the database for this Load Step.

Cancel

Closes the form and restores any settings to its previous state before the form was opened.

Output Requests Output requests are the definition of what output data is desired from the analysis in the form of results such as displacements, stresses, forces, etc. Two formats of this form are available: 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 Create, 277. This default set is used for all output requests in the Basic Output Requests, 364 form described in this section. 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 set on the Create Load Step, 316 for the load step of interest. The Advanced Output Requests, 366 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 reducing the results calculation time for linear perturbation steps and reducing file size for either linear perturbation steps or nonlinear steps. The creation of Patran groups are documented in Group>Create (p. 226) in the Patran Reference Manual.

Main Index

Chapter 3: Running an Analysis Output Requests

. Note:

Main Index

Some 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; not all result quantities cannot be imported and postprocessed in Patran.



The Basic form and its options are described below in Basic Output Requests, 364.



The Advanced form and its options are described below in Advanced Output Requests, 366.



Descriptions of each output request are given below in Output Request Descriptions, 372.



Editing output requests on a global (multi-Load Step) basis is described below in Edit Output Requests, 375.



Customizing the default set of output requests is described below in Customizing Default Output Requests, 378.

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Basic Output Requests This form is used to select output requests with their default options. The FEM entity set associated to these output requests is always All FEM, which means results for all nodes or elements in the model or selected group(s) for analysis. A default set of output requests is always preselected. The table below describes each option.

Main Index

Chapter 3: Running an Analysis Output Requests

Table 3-34 Basic Output Request Options Option

Description

LOAD STEP NAME SOLUTION SEQUENCE

The Solution Sequence as indicated by this value, which is always SOL 400. The available output requests depend on the active Analysis Type on the Load Steps form from which this form was invoked.

Form Type

Toggles the form back and forth from its Basic and Advanced modes. Output requests selected in Basic mode always are set using default parameters. If an output request is selected in Advanced mode it remains as an active output request with its selected settings if the mode is changed back to Basic. In other words, the output request is not reverted back to its default. Once an output request is selected, you must delete the selected output request and reselect it if you wish the default to be restored.

Select Result Type

Select a result type from this form as an output request. Selected results then appear in the Output Requests list. If you reselect an result, you will be warned that the output request has already been selected. You must delete the selected output request form the Output Requests list using the Delete button in order to reselect it from this list box.

Output Requests

This list box contains all the selected output requests. The text shown before the “=” (equals sign) for each item in this list box is exactly as it will be written to the MSC Nastran input deck and corresponds to its proper MSC Nastran entry type format. Everything after the “=” (equals sign) is converted to a proper SET or other keyword for specifying the entities and options for each output request.

Delete

Deletes a selected item from the Output Requests list box. The item must be selected in order for Delete to work.

TITLE

This consists of both an ON/OFF toggle and a text box for the description of the current Load Step. This writes the TITLE keyword and supplied text if the toggle is ON for the current Load Step

SUBTITLE

This consists of both an ON/OFF toggle and a text box for the description of the current Load Step. This writes the SUBTITLE keyword and supplied text if the toggle is ON for the current Load Step

LABEL

This consists of both an ON/OFF toggle and a text box for the description of the current Load Step. This writes the LABEL keyword and supplied text if the toggle is ON for the current Load Step

OK

Accepts the output requests and closes the form.

Defaults

Deletes all output requests in the Output Request list and replaces them with the defaults for the selected solution type on the Load Step form.

Cancel

Closes the form without saving the output requests. Any output request that were present before opening the form are restored.

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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 superelements. The actual output requests available are the same as those on the Basic form, however the Advanced form is sensitive to the Result Type selected. The widgets on the left side of the form plus the OK, Defaults, and Cancel buttons operate exactly like on the Basic Output Requests, 364 form.

The actual widgets that appear on the right side of the form are sensitive to the actual selected output request type. Not all widgets are shown above but all are described in the table below. When an option on the right side is selected or changed, the selected output request is immediately modified in the Output Requests list box.

Main Index

Chapter 3: Running an Analysis Output Requests

In the table below, the column labeled Case Control or Bulk Data indicates the actual keyword included in the output request text. The column labeled Group indicates which type of FEM entities (Nodes or Elements) must be present in the selected group from the Select Group(s)/SET list box. Table 3-35 Advanced Output Request Options Option

Case Control or Bulk Data

Label

Description

General Options for Most Output Request Types* Select Group(s)/SET

Select the group that contains the FEM entities for which this output request is to be applied. Default is All FEM. An error may occur if the selected group does not contain the necessary entity types (nodes or elements).

Sorting

Entity (Node/Element)

SORT1

Output is presented as tabular listing of entities (nodes or elements) for each event (frequency, eigenvalue, time, or load step).

Event (Freq/Time/Step)

SORT2

Output is presented as tabular listing of event (frequency, eigenvalue, time, or load step) for each entity (node or element.

Rectangular

REAL

Requests real and imaginary format for complex output.

Polar

PHASE

Requests magnitude and phase format for complex output.

Von Mises

VONMISES

Requests von Mises stresses or strains.

Maximum Shear

MAXS

Requests Maximum shear or Octahedral stresses or strains.

Cubic

CUBIC

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

Requests QUAD4 stresses or strains at the corner grid points as well as the center.

Center

CENTER

Requests QUAD4 stresses or strains at the center only.

Strain Gage

SGAGE

Requests QUAD4 stresses or strains at the corner grid points as well as the center using the strain gage approach.

Bilinear

BILIN

Requests QUAD4 stresses or strains at the corner grid points as well as the center using bilinear extrapolation.

Format

Tensor

Element Points

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Table 3-35 Advanced Output Request Options (continued) Option

Label

Plate Strain Plane Curv. Curvature

Description

STRCUR

This option is available for Element Strains output requests only. Strains and curvatures are output at the reference plane for plate elements.

Fiber

FIBER

Strains at locations Z1 and Z2 (specified under element properties) are output at the reference plane for plate elements.

Ply Stresses

PARAM, NOCOMPS,1

Composite element ply stresses and failure indices are output. Model should contain PCOMP entry defining composites.

Element Stresses

PARAM, NOCOMPS,-1

Composite element ply stresses and failure indices are suppressed. Element stresses for the equivalent homogeneous element are output.

Ply & Element Stresses

PARAM, NOCOMPS,0

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.

Ply Strains

PARAM, LSTRN,1

Composite element ply strains and failure indices are output. Model should contain PCOMP entry defining composites.

Suppress Print

PLOT

If ON, printed result output to the .f06 file is suppressed (not written) for the selected result output request. If OFF, PRINT is assumed as it is the default in MSC Nastran output requests. Please see the footnote at the bottom of the table.†

Punch File

PUNCH

If ON, the punch file is the output medium for the selected result output request. Please see the footnote at the bottom of the table.‡

Composite Plate Options

Main Index

Case Control or Bulk Data

Chapter 3: Running an Analysis Output Requests

Table 3-35 Advanced Output Request Options (continued) Option

Label

Case Control or Bulk Data

Description

Options Specific to Grid Point Stresses OUTPUT(POST) SURFACE or VOLUME Case Control Output Coordinate

COORD CID

Selects the results output coordinate frame. Coord 0 is the basic coordinate frame.

Volume Output

Both

Blank

Requests direct stress, principal stresses, direction cosines, mean pressure stress and von Mises equivalent stresses to be output. There must be solid elements in the model for this menu option to be set.

Principal

PRINCIPAL

Requests principal stresses, direction cosines, mean pressure stress and von Mises equivalent stresses to be output.

Direct

DIRECT

Requests direct stress, mean pressure stress and von Mises equivalent stresses to be output.

All

FIBER ALL

Specifies that grid point stresses will be output at all fiber 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).

Mid

FIBER MID

Specifies that grid point stresses will be output at the reference plane.

Z1

FIBER Z1

Specifies that grid point stresses will be output at distance Z1 from the reference plane (default Z1=-thickness/2).

Z2

FIBER Z2

Specifies that grid point stresses will be output at distance Z2 from the reference plane (default Z2=+thickness/2).

X1

NORMAL X1

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

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

Specifies the z-axis of the output coordinate frame to be the reference direction for the positive fiber and shear stress output.

Fiber

Normal

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Table 3-35 Advanced Output Request Options (continued) Option Method

X-axis of Basic Coord

Branch

Tolerance

Main Index

Label

Case Control or Bulk Data

Description

Topological

TOPOLOGICAL

Specifies the topological method for calculating average grid point stresses. This is the default.

Geometric

GEOMETRIC

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.

X1

AXIS X1

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.

X2

AXIS X2

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

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

Treats multiple element intersections as stress discontinuities in the geometric interpolation method.

No Break

NOBREAK

Does not treat multiple element intersections as stress discontinuities in the geometric interpolation method.

default = 0.0

TOL 0.0

Defines the tolerance to be used for interelement slope differences. Slopes beyond this tolerance will signify discontinuous stresses.

Chapter 3: Running an Analysis Output Requests

Table 3-35 Advanced Output Request Options (continued) Option

Case Control or Bulk Data

Label

Description

Options Specific to Nonlinear Stress Output NLOUT & UDSESV State Variables

To fully support submittal of MSC Nastran with UDS (user defined subroutines), 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. You must press the RETURN or ENTER key to make this update the spreadsheet below.

State Variable Name

Text box to enter a user defined name of the selected state variable. First select the cell of the state variable to give a User Def. Name. Then enter a value in this data box and press the RETURN or ENTER key to enter it in the selected cell.

Data

This is the spreadsheet displaying the state variables and their names and user defined names. *If a widget is disabled for the selected output request, it is not a valid option for that output request. †The ability to write PRINT, PUNCH, and PLOT settings to the output variables is controlled in two places. It is controlled globally on the Translation Parameters, 291 form if those Print or Punch toggles are ON/OFF. If Punch is OFF on the Translation Parameters form, then the ability to set PUNCH is done by individual output request on this Output Request form in Advanced mode. The ability to suppress the PRINT by using PLOT is also done here on the Output Request form. If the Suppress Print toggle is set ON on the Output Request form, then no PRINT option is written and a PLOT option is written instead. ‡If Punch toggle is ON on the Translation Parameters form, ALL output requests will get the PUNCH option regardless of the settings on the Output Requests form. If the Print toggle is OFF on the Translation Parameter form, then ALL output requests will get the PLOT option regardless of the settings on the Output Requests form. If the toggle is ON, then the setting for Suppress Print will be honored on the Output Request form.

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Output Request Descriptions Table 3-36 Output Request Descriptions Case Control or Bulk Data

Output Request

Description

Structural Output Requests Accelerations

ACCELERATION

Requests nodal accelerations. Selected group must have nodes present or use All FEM designation.

Applied Loads

OLOAD

Requests equivalent nodal applied loads. Selected group must have nodes present or use All FEM designation. For nonlinear Load Step, NLLOAD is the preferred option.

Constraint Forces

SPCFORCES

Requests forces of single- point constraints. Selected group must have nodes present or use All FEM designation.

Contact Results

BOUTPUT

Requests contact regions for output. Selected group must have elements present or use All FEM designation.

Displacements

DISPLACEMENT

Requests nodal displacements. Selected group must have nodes present or use All FEM designation.

Eigenvectors

VECTOR

Requests nodal eigenvectors. Selected group must have nodes present or use All FEM designation. There is no practical difference between this output request and Displacements.

Element Forces

FORCE

Requests elemental forces. Selected group must have elements present or use All FEM designation. Not available when using advanced elements.

Element Strain Energies

ESE

Requests elemental strain energies and energy densities. Selected group must have elements present or use All FEM designation. Not available when using advanced elements.

Element Strains

STRAIN

Requests elemental strains. Selected group must have elements present or use All FEM designation.

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Chapter 3: Running an Analysis Output Requests

Table 3-36 Output Request Descriptions (continued) Case Control or Bulk Data

Output Request

Description

Element Stresses

STRESS

Requests elemental stresses. Selected group must have elements present or use All FEM designation. Do not use for nonlinear Load Steps. Use NLSTRESS instead.

Grid Point Force Balance

GPFORCE

Requests grid point force balance at nodes. Selected group must have nodes present or use All FEM designation.

Grid Point Stresses

GPSTRESS

Requests stresses at grid points. Selected group must have nodes present or use All FEM designation. Not available when using advanced elements.

MultiPoint Constraint Forces

MPCFORCES

Requests forces of multipoint constraints. Selected group must have nodes present or use All FEM designation.

Nonlinear Applied Loads

NLLOAD

Requests equivalent nonlinear applied loads. Selected group must have nodes present or use All FEM designation.

Nonlinear Stress

NLSTRESS

Requests the form and type of nonlinear element stress output. Selected group must have elements present or use All FEM designation.

Velocities

VELOCITY

Requests nodal velocities. Selected group must have nodes present or use All FEM designation.

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Table 3-36 Output Request Descriptions (continued) Case Control or Bulk Data

Output Request

Description

Thermal Output Requests Applied Linear Loads

OLOAD

Requests nodal applied linear loads from heat transfer analysis. Selected group must have nodes present or use All FEM designation.

Contact Results

BOUTPUT

Requests contact regions for output. Selected group must have elements present or use All FEM designation.

Enthalpies

ENTHALPY

Requests nodal temperatures. This output request is only available for transient heat transfer. Selected group must have nodes present or use All FEM designation.

Heat Fluxes

FLUX

Requests heat transfer gradient and flux output. Selected group must have elements present or use All FEM designation.

Heats of Constraints

SPCFORCES

Requests nodal heat constraints for heat transfer analysis. Selected group must have nodes present or use All FEM designation.

Rate of Change of Enthalpies

HDOT

Requests rate of change of enthalpy vector. This output request is only available for transient heat transfer. Selected group must have nodes present or use All FEM designation.

Temperatures

THERMAL

Requests nodal temperatures. Selected group must have nodes present or use All FEM designation.

Main Index

Chapter 3: Running an Analysis Output Requests

Edit Output Requests This form is accessed from the Load Steps, 314 form when the Action is set to Global Data by pressing the Output Requests... button. Use this form to globally edit the outputs request associated with multiple selected Load Steps. The form works in the following manner:

1. After invoking the form by selecting one or more Load Steps from the Load Steps form (Action=Global Data), select any cell or cells of the spreadsheet. 2. Make changes in the Select Group(s)/SET and Options widgets as desired. 3. Press the Fill Cell button to reflect those changes to the output request(s) in the actual spreadsheet cells. 4. Press the Default button if you wish for a cell to contain the default output request for that result type. Or select and entire row and press the Step Defaults to restore all the output requests for a particular Load Step to its defaults (based on the Load Step’s analysis type). 5. To clear an output request from cell or cells, press the Clear Cell(s) button.

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6. If you make a mistake you can back up your changes by pressing the Undo button as many times as necessary as long as the form remains open. 7. Press the OK button to save the changes made in the spreadsheet and close the form or press Cancel if you decide not to keep any of your changes. 8. On the Load Steps form (Action = Global Data) press the Apply button. This will recreate all your Load Steps with the modified output requests. Table 3-37 Edit Output Request Options Option

Description

Load Step Name Solution Sequence Results Type Output Request

This are simply labels that are displayed and change based on the actual output request selected in the spreadsheet on this form. If multiple cells are selected, the first selected cell contents is displayed as the Result Type and Output Request.

Select Group(s)/SET Options

These widgets provide the means for changing a particular output request for a selected type such a Displacement. The description of these options is identical to those on the Advanced Output Requests, 366 form. Please see Table 3-35. Making changes to these widgets does nothing until one of the buttons on the form is pressed. Any disabled (greyed out) widget in this area signifies that the option is not valid for the selected result type.

Fill Cell

Press this button to change the selected spreadsheet cells based on the current settings of the Select Group(s)/SET and Options widgets. The cell contents are not updated until this button is pressed. Simply making changes to the widgets does nothing.

Default

This button fills the selected cell(s) with the default output request.

Spreadsheet

The rows of the spread sheet correspond to the selected Load Steps and the row labels contain the Load Step names. The column labels contain the names of all the supported output request types. The cell contents display the defined output request for the Load Step (row) and result type (column). You must select cells in order to change any cell contents.

Undo

This button will undo a change made to the spreadsheet as long as the spreadsheet remains open. Once the Cancel button is pressed or a new set of Load Steps is selected, the undo capability resets itself. Multiple undo levels are possible.

Step Defaults

If an entire single row of cells is selected, this button fills all those cells with the default output requests for the given Load Step’s analysis type.

Clear Cell(s)

This button simply clears the selected cells of any output request.

OK

This button saves the changes made on the spreadsheet and close the form.

Cancel

This button closes the form and reverts any changes back to the way they were when the form was first opened. Notes:

Main Index



The Edit Output Requests form opens with focus in the first result type of the first Load Step.



The top half of the Edit Output Requests form is similar to the Advanced Output Request form.

Chapter 3: Running an Analysis Output Requests

Main Index



The spreadsheet column labels are the available result types. You will have to scroll over to see all of them.



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, Results Type, gets updated with the result type of the currently selected cell. The Output Requests databox gets updated to show the actual content of the cell. All the widgets in Select Group(s)/SET and Options frame are updated to show the settings of this selected output request. If more than one cell is selected, the settings are that of the first selected 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).



Selecting a column header will allow you to change all Load Step 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.



Cells are NOT filled with the contents of output requests that are not appropriate to the analysis type of the selected Load Steps. A warning is issued in this case the first time this is attempted. In other words, if you try to fill a Temperature cell of a structural Load Step, the warning is issued. If you try to fill a Displacement cell of heat transfer Load Step, the warning is issued. The cell(s) are not populated.

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Customizing Default Output Requests To properly make use of this feature you need to create a PCL file that contains the function user_change_default_out_req(sseq) which overwrites the existing default file in Patran. This 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. Please see Accessing PCL Functions (p. 23) in the PCL and Customization for further details on how to do this. In the example below, the user_change_default_out_req(sseq)function makes use of the nas_implnl_user_add_out_req and the nas_implnl_user_del_out_req functions to add and delete default output request types. These two functions are defined as follows:

nas_implnl_user_add_out_req

( or_num, or_string, sseq, def_of )

Description: This function adds an output request type to the list of default output requests and allows you to change the default settings of that output request. Input: INTEGER or_num The output request (OR) number of the output request type to add See Table 3-38. STRING or_string The string or values of the selected output request type. If left blank (empty string), the standard default is used. See Table 3-38. INTEGER sseq A special solution sequence number identifying which analysis type this output request is associated. LOGICAL def_or Flag to specify whether this output request should be part of the default list of output requests for the given analysis type (sseqnum). If TRUE, the output request is displayed in the Output Request list box when the Default button is pressed. Output: INTEGER return_value Returns the following error status:

Main Index

0

successful

-1

the output request is not one listed in Table 3-38

-2

the output request # is greater than that supported

-3

the sseqnum is not one listed in Table 3-38

-4

the output request string is not valid

-5

the output request string is too long (256 max)

Chapter 3: Running an Analysis Output Requests

nas_implnl_user_del_out_req

(or_num)

Description: This function deletes the specified output request type from the list of default output requests. It no longer will show up when the Default button is pressed. Input: INTEGER or_num The output request number of the output request type to remove as default. See Table 3-38. Output: INTEGER return_value Returns the following error status: 0

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successful

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Example:

This line would be placed in you p3epilog.pcl file and the file placed in either the local working directory, your home directory, or the Patran installation location (P3_HOME). !!input /home/default_out_req.pcl A file called default_out_req.pcl would be created containing the following PCL function. Note that the path were this file is located must be reflected in the line above in the p3epilog.pcl file. FUNTION user_change_default_out_req(sseq) INTEGER sseq /* sseqnum gets automatically passed into this routine */ SWITCH( sseq ) CASE(401) /* * * * * * * * */

For sseqnum=401 (Statics), this changes the default output request definition for MPCFORCES (4) and makes it appear as a default output request. It also makes GPSTRESS (10) and OLOAD (6) default output requests but does not change their default definitions. And finally it removes DISPLACEMENT (1), STRESS (2), and SPCFORCES (3) as default output requests.

nas_implnl_user_add_out_req( 4,"MPCFORCES(SORT2,REAL)=ALL FEM",sseq,TRUE) nas_implnl_user_add_out_req(10," " ,sseq,TRUE) nas_implnl_user_add_out_req( 6," " ,sseq,TRUE) nas_implnl_user_del_out_req(1) nas_implnl_user_del_out_req(2) nas_implnl_user_del_out_req(3) CASE(459) /* * * * * *

For sseqnum=459 (Transient Heat), this changes the default output request definition for ENTHALPY (35) and HDOT (36), but it only allows ENTHALPY to be in the list of default output requests. And finally it removes TEMPERATURE (31), FLUX (32), OLOAD (33) and SPCFORCES (34) as default output requests.

nas_implnl_user_add_out_req(35,"ENTHALPY(SORT2)=ALL FEM" nas_implnl_user_add_out_req(36,"HDOT(SORT2)=default_group" nas_implnl_user_del_out_req(31) nas_implnl_user_del_out_req(32) nas_implnl_user_del_out_req(33) nas_implnl_user_del_out_req(34) END SWITCH END FUNCTION

Main Index

,sseq,FALSE) ,sseq,TRUE )

Chapter 3: Running an Analysis Output Requests

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 analysis types. Table 3-38 Analysis Type (sseq) vs Result ID Number (or_num) Result ID (or_num) sseq

1

2

3

4

5

6

7

8

9

10

11

12

13

401

x

x

x

o

o

o

o

o

o

o

o

o

o

403

o

x

x

o

o

o

o

o

o

o

o

o

o

405

o

x

x

o

o

o

o

o

o

o

o

o

o

409

x

x

x

o

o

o

o

o

o

o

o

o

o

16

20

21

o

o

x

o

o

x

o

o

o

o

31

32

33

34

453

o

x

x

o

o

459

o

x

x

o

o

Valid sseq values (Analysis Type): 

401=Statics



403=Normal Modes



405=Buckling



409=Dynamics



453=Steady State



459=Transient Heat

Valid or_num values for the Results Id (output request type):

Main Index



1=DISPLACMENT



12=ACCELERATION



2=STRESS



13=GPFORCE



3=SPCFORCE



16=VECTOR



4=MPCFORCE



20=NLSTRESS



5=FORCE



21=BOUTPUT (contact)



6=OLOAD



31=THERMAL



7=NLLOAD



32=FLUX



8=ESE



33=OLOAD (for heat transfer)



9=STRAIN



34=SPCFORCES (for heat transfer)



10=GPSTRESS



35=ENTHALPY



11=VELOCITY



36=HDOT

35

36

o

o

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Default Definition (or_string)

or_num

Main Index

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

16

VECTOR(SORT1,REAL)=All FEM

20

NLSTRESS(SORT1)=All FEM

21

BOUTPUT(SORT1,REAL)=All FEM

31

THERMAL=(SORT1)=All FEM

32

FLUX(SORT1)=All FEM

33

OLOAD(SORT1)=All FEM

34

SPCFORCES(SORT1)=All FEM

35

ENTHALPY(SORT1)=All FEM

36

HDOT(SORT1)=All FEM

Chapter 3: Running an Analysis Load Step Select

Load Step Select This form appears when the Load Step Select... button is selected on the Analysis form. This form is used to select a sequence of Load Steps associated with an analysis job.

Note:

The load case associated with the first Load Step selected must be the same load case that you have selected as the Initial Contact Pair load case. See Contact Control Parameters, 302 for details.

By default this form appears with one Subcase defined with a single Load Step (Default) The form works in this manner: 1. Add Subcases: Right mouse button (RMB) click on the job name in the widget Tree. The first item in the Tree is the current analysis job name. Click on Add Subcase.

This RMB menu on the top level jobname Tree item also allows you to Remove All Subcases and Expand All or Collapse All Tree widget items. Note that if you remove all Subcases, this naturally removes all association of Load Steps to the Subcases. See the discussion below on the differences between Subcases and Load Steps.

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The Subcase names cannot be changed. They appear as Subcase1, Subcase2, Subcase3, etc. 2. Add Load Steps: Once a Subcase is available in the Tree, RMB click on the respective Subcase to add a Load Step. Select Add Load Step. This is actually a cascading menu that allows you to select an existing Load Step.

You can also add Load Steps by clicking on the Subcase of interest (or any Load Step within that Subcase) and select an existing Load Step from the list box on the right hand side of the form. This is sometimes more convenient in that this allows for multiple selections at once rather than one at a time through the RBM procedure. Other RMB options when accessing a Subcase Tree level item are to Add Subcase, Delete Subcase, Remove All Load Steps, Move Up, Move Down. These are pretty much self-explanatory but more detail is given in the table below. 3. Move Load Steps: If you make a mistake and get the order of the Load Steps incorrect, you can easily move them up or down within their own Subcase. Use the RBM with a Load Step Tree item selected. Just select the Move Up or Move Down item.

4. Save the Step: Press the OK button to save this Subcase/Load Step configuration for the job. The data is not actually saved in the database until you press the Apply button on the main Analysis form.

Main Index

Chapter 3: Running an Analysis Load Step Select

Table 3-39 Load Step Select Options Option

Description

Subcase/Step Configuration

The left-hand side of the form shows a Tree widget configuration of defined Subcasea and their associated Load Steps. This is how the Nastran SUBCASE and STEP configuration will appear in the input deck on translation.

Available Load Steps

This is a list of available (defined) Load Steps. Selecting one or more of these causes the Subcase/Step Configuration Tree on the left-hand side of the form to update with the selected Load Steps. The Load Steps are added or removed from the actively selected Subacase (or its child Load Steps) depending on the Add Steps/Remove Steps switch setting. Note that when removing Load Steps using this list box, if a Load Step appears more than once within the Subcase, all occurrences are removed.

Filter

You can filter the displayed (available) Load Steps by pressing this button and changing the text in the data box to the right of this button. An “*” acts as a wild card.

Add Steps Remove Steps

The setting of this switch affects how Load Steps are added/removed from the Tree widget when Load Steps are selected from the Available Load Steps list box. Note that while the form is open the switch dictates whether Load Steps are added or removed from the Tree. When the form is closed and subsequently reopened, the switch setting reverts to its default, which is to Add Steps.

OK

Press the OK button to save the Subcase/Step Configuration. Once the Apply button is pressed on the Analysis form, the configuration is saved with the job in the database.

Cancel

Press the Cancel button to close the form and discard any changes made while this form was open. Tree widget Right Mouse Button (RMB) options:

Add Subcase

Adds a Subcase level to the Tree widget. Note that the Subcase names are fixed and cannot be modified. They are Subcase1, Subcase2, Subcase3, etc. If a Subcase is removed, the Subcases are renamed such that they continue to indicate Subcase1, Subcase2, Subcase3, etc. No gaps in the numbering are allowed.

Remove All Subcases

Removes all the Subcase from the Tree widget. If the form is closed in this state, the default configuration is be restored when the form is next opened.

Remove Subcase

Removes the selected Subcase and its Load Steps from the Tree widget. The selected item can be the Subcase itself or any Load Step within the Subcase or interest.

Expand All

Expands the entire Tree widget showing all Subcases and associated Load Steps.

Collapse All

Collapses the entire Tree widget showing only the job name item.

Add Load Step

Adds the Load Step selected from the cascading menu that appears.

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Table 3-39 Load Step Select Options (continued) Option

Description

Remove Load Step

Removes the selected Load Step from the associated Subcase.

Remove All Load Steps

Removes all the Load Steps from the associated Subcase.

Move Up

Move an item up in the Tree widget. If the item is a Load Step, it moves above the one just above until it becomes the first Load Step of the associated Subcase, it remains at that level. Moving a Subcase up does the same operation at a Subcase level and carries with it all of its associated Load Steps.

Move Down

Move an item down in the Tree widget. If the item is a Load Step, it moves below the one just below it until it becomes the last Load Step of the associated Subcase, it remains at that level. Moving a Subcase down does the same operation at a Subcase level and carries with it all of its associated Load Steps.

Main Index

Chapter 3: Running an Analysis Load Step Select

Subcases versus Load Steps MSC Nastran SOL 400 analyses consist of SUBCASEs and associated STEPs. At least one SUBCASE must be defined. The solution of all SUBCASES are independent of each other. The can be considered as separate analyses and the same thing could be accomplished with different input decks each representing one of the SUBCASE configurations. A STEP (Load Step) is a continuation of the solution of the previous STEP. During the analysis any subsequent STEP after the first on encountered continues with the state (loads, stiffness, etc.) where the last STEP left off. Here’s an example of two SUBCASE (two separate analyses) each with two STEPs (Load Steps): SUBCASE 1 STEP 1 LOAD STEP 2 LOAD SUBCASE 2 STEP 10 LOAD STEP 20 LOAD

= 1 = 2 = 10 = 20

This could correspond to the Tree widget as shown here:

This mechanism allows for multi-analysis load stepping where there can be single physics analysis or chained multi-physics analysis but with only one physics type per STEP. The above example could be representative of the following if Load Step 1 is Steady State Heat transfer and Load Steps 2 & 3 are Statics (nonlinear) and Load Step 4 is Normal Modes. SUBCASE 1 STEP 1 ANALYSIS STEP 2 ANALYSIS SUBCASE 2 STEP 10 ANALYSIS STEP 20 ANALYSIS

Main Index

= HSTAT = NLSTAT = NLSTAT = MODES

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In the example above, for the first SUBCASE, the NLSTAT Load Step uses the temperatures from the HSTAT Load Step. STEP 2 does not influence STEP 10 at all. SUBCASE 2 is the start of a new analysis. STEP 20 determines modes based on the analysis state at the end of STEP 10.

Main Index

Chapter 4: Supported Entities MSC Nastran Implicit Nonlinear (SOL 600) User’s GuidePatran MSC Nastran Preference Guide - Implicit Nonlinear

4

Main Index

Supported Entities



MSC Nastran Results Access



MSC Nastran Input File Import



Supported Model Entities



Files Created

428

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401

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MSC Nastran Results Access This form appears when the Analysis tab/application toggle is selected on the main menu and the Action is set to Access Results.

Main Index

Chapter 4: Supported Entities MSC Nastran Results Access

Table 4-1 Access Results Item Object

Description The Object you select defines the type of results file to be accessed from the analysis. The following file types are available: Output2 and MASTER. Note that the word accessed is used as opposed to import. Results remain in the results files and are not actually imported into the Patran database. Only the meta data that describes the available results is imported. This type of results access is refereed to as Direct Results Access or DRA for short. For a brief description of these supported results file formats, see Results File Formats, 392. With the Action set to Access Results, the available Objects are: 

Attach HDF5- select an MSC Nastran HDF5 (.h5) file from which to access results.



Attach Master- select an MSC Nastran MASTER file from which to access results.



Attach OP2- select an MSC Nastran OP2 file from which to access results.

With the Action set to Delete, the available Objects to remove results attachments are: 

MASTER Attach - disconnects from the MASTER file.



OP2 Attachment- disconnects from the OP2 file.

Deleting results attachments does not delete results or affect these files in any way since the results were never imported into the database. The results simply are no longer accessible. Method

The Method choices for accessing MASTER files are: Result Entities, Model Data, or Both. For Output2 files, only Result Entities can be accessed. When selecting Results Entities, the model must already exist in the database or error will occur. For MASTER files , when selecting Model Data or Both, the actual nodes and elements of the model are imported into the Patran database including coordinate systems, material properties, physical properties, loads and boundary conditions, load cases, parameters and etc... For HDF5 files, when selecting Model Data or Both, only the actual nodes and elements of the model are imported into the Patran database

Jobname

See Select Results File... entry below.

Select Results File...

This brings up a file browser to select the results file to access. By default the file name is the jobname.h5, jobname.MASTER, or jobname.OP2. Therefore it is only necessary to select a file if it differs from the jobname.

Translation Parameters...

Parameters, 394.

Entity Selection...

Defines which model entities to import. See Entity Selection Form, 404.

Main Index

Defines the parameters used to control the results or model translation. See Results Translation

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Results File Formats HDF5 Formats This is a MSC Nastran HDF5 (.h5) file containing results from SOL 400 runs. The h5 file is created by including the MDLPRM,HDF5,1 entry in the bulk data section of the input deck. Include this in Direct Text Input, 312 when creating/running a job. As an alternative way, the system cell 702 can be given in command line as the following: nastran example.dat sys702=1 Import of Model data also supported only for nodes and elements from h5 file thus it is recommended to import the corresponding input deck to get the complete model data before importing the h5 file for result entities.

Output2 Formats This is a standard MSC Nastran OUTPUT2 file containing results from SOL 400 runs. It is created by including the PARAM,POST,1 entry in the bulk data section of the input deck. See Translation Parameters, 291 on how to set this on translation when running a job. Although an OP2 file is being attached when selected, internally the OP2 file is converted to a temporary MASTER file for results access. Please read the MASTER Formats, 392 section for a full understanding of results access.

MASTER Formats Using the MASTER format, you can attach to the MSC Nastran database directly saving the extra step of creating an alternate form of MSC Nastran results data, i.e. OP2. Because the model and results data in the MSC Nastran database tends be sequential in nature, an index provides fast direct access to the data. The DRA capability uses the MSC Nastran toolkit capability, which interfaces with the MSC Nastran executable in a client-server mode. This requires access to an MSC Nastran installation or the MSC Nastran mini server delivered with Patran. When accessing MASTER files, both the MASTER and the DBALL file are generally required, however, see the next sections discussion.

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Results Access Settings To point to an MSC Nastran installation, the location of the MSC Nastran executable is set in the following files: P3_TRANS.INI (Windows)

or site_setup (Linux).

On Windows, the following command setting must be set to point to the MSC Nastran executable: ACommand20xx

On Linux, the command setting is: MSP_NASTRAN_CMD20xx

Note: It is required to point to MSC Nastran 2004 or later. If you specify an MSC Nastran executable earlier than 2004 you will be presented with a modal form preventing you from using this capability. However, you may bypass this restriction by setting the DRA_NAST_NOVEDRCHK environment variable.

MASTER vs DBALL An MSC Nastran database is indexed and saved by setting NASTRAN SYSTEM cell 316 to a value of seven (7). This system cell tells MSC Nastran to create index files for IFP and OFP data blocks and move the indexed data blocks to the MASTER file. This means that one can even delete the DBALL file after the run completes. For example, if you would like to get an indexed MASTER data file for the job jobname.bdf, submit MSC Nastran with the following: nastran jobname.bdf sys316=7 scr=no sdir=/tmp This example generates a jobname.MASTER and jobname.DBALL database files. You can delete the DBALL file because it does not contain any results or model data of importance. To perform a restart, though, the DBALL file must be retained, but the MASTER file may be moved to other directories at will. When creating the MSC Nastran input file using Patran, the Nastran line is used to set the SYSTEM(316) cell to seven (7) or 19 automatically depending on your setting on the model Translation Parameters, 291 form, which corresponds to MASTER Only or MASTER/DBALL, respectively. In the latter case you must retain both the MASTER and DBALL files to access results.

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Results Translation Parameters This subordinate form appears when the Translation Parameters button is selected. This form affects import of objects as noted below

Table 4-2 Results Translation Parameters Item Tolerances 

Division



Numerical

Description Defines the tolerances used during translation. The division tolerance is used to prevent division by zero errors. The numerical tolerance is used when comparing real values for equality.

Additional Results to be Imported

Indicates which results categories are to be filtered out during translation. Rotational Nodal Results, Stress and Strain Invariants, and Stress and Strain Principal Direction Results can be skipped during translation. Items selected are translated. Items not selected are skipped. By default, all are ignored during translation.

Element Results Positions

If an element has results at both the centroid and at the nodes, this filter will indicate which results are to be included in the translation.

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Supported Result Quantities The following table indicates the possible results quantities that can be accessed from MSC Nastran. The Primary and Secondary Labels are items selected from the postprocessing menus. The Type indicates whether the results are Scalar, Vector, or Tensor, and determines which postprocessing techniques are available to view the results quantity. Data Block indicates which MSC Nastran data block the data comes from. The Description gives a brief discussion about the results quantity, such as if it is only for certain element types, and what Output Request selection will generate this data block.

Table 4-3 Supported Result Quantities Primary Label Bar Forces

Bar Strains

Bar Stresses

Grid Point Stresses

Gap Results

Main Index

Secondary Label

Type

DataBlocks

Description

Rotational

Vector

Bar moments

Translational

Vector

Warping Torque

Scalar

Warping torque

Axial Safety Margin

Scalar

Axial safety margin

Compression Safety Margin

Scalar

Safety margin in compression

Maximum Axial

Scalar

Minimum Axial

Scalar

Tension Safety Margin

Scalar

Safety margin in tension

Torsional Safety Margin

Scalar

Safety margin in torsion

Axial Safety Margin

Scalar

Axial safety margin

Compression Safety Margin

Scalar

Safety margin in compression

Maximum Axial

Scalar

Minimum Axial

Scalar

Tension Safety Margin

Scalar

Safety margin in tension

Torsional Safety Margin

Scalar

Safety margin in torsion

Stress Tensor

Tensor

Stress tensor

Zero Shear Angle

Scalar

Zero shear angle

Major Principal

Scalar

Minor Principal

Scalar

Maximum Shear

Scalar

Maximum shear

von Mises

Scalar

von Mises

Displacement

Vector

Gap element displacement

Force

Vector

Slip

Vector

OEF1

OSTR1

OES1

OGS1

OEF1 or OES1

Bar forces

Maximum axial strain Minimum axial strain

Maximum axial stress Minimum axial stress

Major principal Minor principal

Gap element force Gap element slip

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Table 4-3 Supported Result Quantities Primary Label

Secondary Label

Type

Creep Strain

Scalar

Nonlinear Strains Plastic Strain

Scalar

Nonlinear Stresses

Principal Strain Direction

Principal Stress Direction

Main Index

DataBlocks

Description Creep strain

OESNL1

Plastic strain

Strain Tensor

Tensor

Strain tensor

Equivalent Stress

Scalar

Stress Tensor

Tensor

1st Principal x cosine

Scalar

1st Principal x cosine

1st Principal y cosine

Scalar

1st Principal y cosine

1st Principal z cosine

Scalar

1st Principal z cosine

2nd Principal x cosine

Scalar

2nd Principal x cosine

2nd Principal y cosine

Scalar

2nd Principal z cosine

Scalar

3rd Principal x cosine

Scalar

3rd Principal x cosine

3rd Principal y cosine

Scalar

3rd Principal y cosine

3rd Principal z cosine

Scalar

3rd Principal z cosine

Zero Shear Angle

Scalar

Zero shear angle

1st Principal x cosine

Scalar

1st Principal x cosine

1st Principal y cosine

Scalar

1st Principal y cosine

1st Principal z cosine

Scalar

1st Principal z cosine

2nd Principal x cosine

Scalar

2nd Principal x cosine

2nd Principal y cosine

Scalar

2nd Principal z cosine

Scalar

3rd Principal x cosine

Scalar

3rd Principal x cosine

3rd Principal y cosine

Scalar

3rd Principal y cosine

3rd Principal z cosine

Scalar

3rd Principal z cosine

Zero Shear Angle

Scalar

Zero shear angle

OESNL1

OSTR1

OES1

Equivalent stress Stress tensor

2nd Principal y cosine 2nd Principal z cosine

2nd Principal y cosine 2nd Principal z cosine

Chapter 4: Supported Entities MSC Nastran Results Access

Table 4-3 Supported Result Quantities Primary Label

Shear Panel Forces

Shear Panel Strains

Shear Panel Stresses

Secondary Label

Type Scalar

Shear force from nodes 1 to 2

Force14

Scalar

Shear force from nodes 1 to 4

Force21

Scalar

Shear force from nodes 2 to 1

Force23

Scalar

Shear force from nodes 2 to 3

Force32

Scalar

Shear force from nodes 3 to 2

Force34

Scalar

Force41

Scalar

Force43

Scalar

Shear force from nodes 4 to 3

Kick

Scalar

Kick forces

Rotational

Vector

Moments at nodes

Shear

Scalar

Shear force in panel

Translational

Vector

Forces at nodes

Average Shear

Scalar

Average shear strain in panel

Maximum Shear

Scalar

Safety Margin

Scalar

Shear safety margin of panel

Average Shear

Scalar

Average shear stress in panel

Maximum Shear

Scalar

Safety Margin

Scalar

Shear safety margin of panel

Force Resultant

Tensor

Force resultants and moment resultants

Moment Resultant

Tensor

Moment stress resultants

Strain Tensor

Tensor

Strain curvatures of a plate

1st Principal

Scalar

Curvature of strain 1st principal

2nd Principal

Scalar

Curvature of strain 2nd principal

OEF1

OSTR1

OES1

OEF1

Strain Curvatures Maximum Shear

Main Index

Description

Force12

Shell Forces

Strain Energy

DataBlocks

Scalar

OSTR1

Shear force from nodes 3 to 4 Shear force from nodes 4 to 1

Maximum shear strain in panel

Maximum shear stress in panel

Curvature of maximum shear strain

von Mises

Scalar

Curvature of von Mises strain

Zero Shear Angle

Scalar

Curvature of zero shear angle

Energy

Scalar

Element’s total strain energy

Energy Density

Scalar

Percent of Total

Scalar

ONRGY1

Element’s strain energy density Element’s percentage of total strain density

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Table 4-3 Supported Result Quantities Primary Label

Strain Invariants

Strain Tensor

Stress Invariants

Stress Tensor Accelerations

Secondary Label

Type

Displacements Eigenvectors Nonlinear Applied Loads Velocities

Main Index

Description

1st Principal

Scalar

Strain 1st principal

2nd Principal

Scalar

Strain 2nd principal

3rd Principal

Scalar

Strain 3rd principal

Maximum Shear

Scalar

Mean Pressure

Scalar

Mean strain pressure

Octahedral Shear

Scalar

Octahedral shear strain

von Mises

Scalar

von Mises equivalent strain

NONE

Tensor

1st Principal

Scalar

Stress 1st Principal

2nd Principal

Scalar

Stress 2nd Principal

3rd Principal

Scalar

Strain 3rd Principal

Maximum Shear

Scalar

Mean Pressure

Scalar

Mean stress principal

Octahedral Shear

Scalar

Octahedral shear stress

von Mises

Scalar

von Mises equivalent stress

NONE

Tensor

Rotational

Vector

Translational

Vector

Rotational

Vector

Translational

Vector

Nodal equivalent applied forces

Rotational

Vector

Nodal moments of single-point constraints

Translational

Vector

Rotational

Vector

Translational

Vector

Rotational

Vector

Translational

Vector

Rotational

Vector

Translational

Vector

Rotational

Vector

Translational

Vector

Applied Loads

Constraint Forces

DataBlocks

OSTR1

OSTR1

OES1

OES1 OUGV1

OPG1

OQG1

OUGV1 OPHIG OPNL1 OUGV1

Maximum shear strain

Strain tensor

Maximum shear stress

Stress tensor Nodal angular accelerations Nodal translational accelerations Nodal equivalent applied moments

Nodal forces of single-point constraint Nodal rotational displacements Nodal translational displacements Nodal rotational eigenvectors Nodal translational eigenvectors Nodal nonlinear applied moments Nodal nonlinear applied forces Nodal angular velocity Nodal translational velocity

Chapter 4: Supported Entities MSC Nastran Results Access

Table 4-3 Supported Result Quantities Primary Label Error

Secondary Label

DataBlocks

Scalar

Elements

Vector

Internal nodal force contribution by element

Applied Loads

Vector

Nodal equivalent applied forces

Vector

ERROR

Description

Estimate

Grid Point Forces Constraint Forces

Grid Point Moments

Type

Elemental error in adaptive analysis

OGPFB1*

Nodal equivalent constraint forces

Total

Vector

Total nodal equivalent forces due to internal loads, applied loads and constraint forces.

Elements

Vector

Internal nodal moment contribution by element

Applied Loads

Vector

Nodal equivalent applied moments

Constraint Forces

Vector

Total

Vector

OGPFB1*

Nodal equivalent constraint moments Total nodal equivalent moments due to internal loads, applied loads and constraint forces.

Global Variables In addition to standard results quantities, a number of Global Variables are created when accessing results. This table outlines global variables that may be created. Global Variables are results quantities where one value is representative of the entire model. Global variables are typically used in making plots/graphs of a result quantity vs a global variable, for example stress vs. time at a particular node. Table 4-4 Supported Global Variables Labels

Main Index

Description

Critical Load Factor

Value of buckling load for the given buckling mode.

Time

Time value of the time step.

Frequency

Frequency value of the frequency step or for the normal mode.

Damping Ratio

Damping ratio value of a complex eigenvalue analysis.

Eigenvalue

Eigenvalue for normal modes or complex eigenvalue analysis.

Percent of Load

Percent of load value for a nonlinear static analysis.

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Coordinate Systems In some cases, the elemental stresses and strains are transformed from one coordinate frame to another when accessed via Patran. The following describes the coordinate systems for element results when they are access and plotted by Patran’s postprocessing application. The coordinate system names referred to are described in the Patran or the MSC Nastran documentation. Table 4-5 Result Coordinate Systems Element

Description

CTRIA3

Results are in the MSC Nastran system which coincides with the Patran IJK system. At the user’s request during postprocessing, these results can be transformed by Patran to alternate coordinate systems. If the user selects a component of a stress or strain tensor to be displayed, by default, the Results application transforms the tensor to a projected global system.

CQUAD4

Results are in the MSC Nastran “bisector” coordinate system but may be transformed by Patran to alternate coordinate systems (e.g., global) during postprocessing. If the user selects a component of a stress or strain tensor to be displayed, by default, the Results application transforms the tensor to a projected global system.

CHEXA, CPENTA, CTETRA

The user can request that MSC Nastran compute element results in either a local element or alternate coordinate system via the PSOLID entry. If the element results are in the local element system, these are converted to the Patran IJK system on import. If the results are in a system other than local element, they are accessed in this system. These results may be transformed to alternate systems during postprocessing.

CQUAD8, CTRI6

The elemental coordinate system, used by MSC Nastran for results, is described in the MSC Nastran documentation. These results are accessed by Patran “as-is”. These results can be postprocessed in Patran using the “as-is” options, but they cannot be transformed to alternate coordinate systems.

Projected Global System

The projected system is defined as follows. First, the normal to the shell surface is calculated. This varies for curved elements and is constant for flat elements. If the angle between the normal and the global x-axis is greater than 0.01 radians, the global x-axis is projected onto the shell surface as the local x-axis. If the angle is less than 0.01 radians, either the global y-axis or the z-axis (whichever makes the largest angle with the normal) is defined to be the local x-axis. The local y-axis is perpendicular to the plane defined by the normal and the local x-axis. Supported HDF5 Result Quantities

All the result quantities supported through XDB, new OUTPUT2 and MASTER are supported in HDF5 and the new support through HDF5 includes:

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Acoustic Pressure



Acoustic Intensity



Acoustics/Velocity

Chapter 4: Supported Entities MSC Nastran Input File Import



Acoustic Accelerations



Complex Forces in Bars both translation and rotation



Complex CFAST Forces both translation and rotation



CWELD Moments



Strain Energy



CBAR axial and bending strain and stress



CBAR complex axial and bending strain and stress



CBEND axial and bending strain and stress



CBEND complex axial and bending strain and stress



CHEX 20 – Nonlinear strains and stresses

MSC Nastran Input File Import This form appears when the Analysis tab/application toggle is selected on the main menu and the Action is set to Read Input File to translate the input file into the Patran database.

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Table 4-6 Input File Import Item

Description

Jobname

After import, a new jobname appears by the name of the input file.

Entity Selection...

Defines which model entities to import. See Entity Selection Form, 404.

Select Input File...

This brings up a file browser to select the input file to access.

Import Notes When importing SOL 400 input files, it is suggested that you set the Analysis Preference to Implicit Nonlinear first. 

SOL 400 Input Files: • If a SOL 400 input file is detected, and the Analysis Preference is already set to Implicit

Nonlinear, the file is imported with no further interaction by the user. • If a SOL 400 input file is detected, and the Analysis Preference is NOT set to Implicit Nonlinear,

you will be asked if you wish to change the Analysis Preference to Implicit Nonlinear before importing. It is recommended to answer YES to this question. If you answer NO, the preference is not changed. Some entities such as materials and element properties may not be compatible with the set preference. When you subsequently change preferences and incompatible entities are detected, you may be notified and asked if you wish to convert them. If you are planning on remaining and working in the Implicit Nonlinear, preference, answer YES. If not, answer NO and your material and element property values remain unmodified allowing you to switch back to the original preference and continue working as if nothing changed. 

Non-SOL 400 Input Files: • If a non-SOL400input file is detected on import when the Analysis Preference is set to Implicit

Nonlinear, you are notified and asked if you wish to switch the preference to the appropriate preference, i.e., Structural, Thermal, or Explicit Nonlinear. • If the Analysis Preference is NOT set to Implicit Nonlinear, then the input files are imported

without further interaction from the user.

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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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Table 4-7 Model Entity Selection Action

Description

Entity Packets

Highlighted entity types are imported. See Table 4-8.

Select None Select All Select All FEM Select All LBC

Simple buttons to help with the entity selection in the above list box.

Define Offsets...

Activates the form to define ID offsets. See Define Offsets Form, 406.

Create Prop. & Matl. Groups

Turn this ON to create groups based on property sets and materials.

Retrieve Names From Comments

Turn this toggle ON to tell Patran to attempt to retrieve the names of properties and materials from the comments embedded in the input file comments just above the imported entity. This currently only applies to material and element properties names. The names in the comments must be encoded properly. See Numbering Options, 296 in the Translation Parameters, 291 form when creating input files from Patran.

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. Table 4-8 Import Entity Types Entity Type

MSC Nastran Entries

Nodes

GRID, GRDSET, SPOINT

Elements

BAROR, BEAMOR, CBAR, CBEAM, CDAMP1, CDAMP2, CDAMP3, CDAMP4, CELAS1, CELAS2, CELAS3, CELAS4, CGAP, CHEXA, CMASS1, CMASS2, CMASS3, CMASS4, CONM1, CONM2, CONROD, CPENTA, CQUAD4, CQUAD8, CQUADR, CQUADX, CROD, CSHEAR, CTETRA, CTRIA3, CTRIA6, CTRIAR, CTRIAX, CVISC, CIFQUAD, CIFHEX, CIFPENT, CIFQDX.

Material Properties

MAT1, MAT2, MAT3, MAT4, MAT5, MAT8, MAT9, MATEP, MATF, MATG, MATHE, MATORT, MATS1, MCOHE.

Element Properties

PBAR, PBCOMP, PBEAM, PCOMP, PDAMP, PELAS, PGAP, PMASS, PROD, PSHEAR, PSHELL, PSOLID, PVISC, PBARN1, PBEMN1, PSHEARN, PSHLN1, PSHLN2, PSLDN1, PCOHE.

Coordinate Frames

CORD1C, CORD1R, CORD1S, CORD2C, CORD2R, CORD2S.

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Table 4-8 Import Entity Types Entity Type

MSC Nastran Entries

Load Sets

FORCE, GRAV,MOMENT, PLOAD1, PLOAD2, PLOAD4, PLOADX1, RFORCE, TEMP, TEMPP1, TEMPRB, SPC, SPC1, SPCD, VCCT.

Load Steps

LOAD, SPCADD, Case Control.

MPC Data

RBE2, RBE3, BOLT.

Comment Lines

All items starting with a "$" are added to the imported job as Direct Text Input (DTI). Also unrecognized entries are also imported. Turning this selection OFF does not import any entries beginning with a "$", however unrecognized entries are still 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. By default only 1000 comment lines and 1000 unrecognized entries are 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 causes 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.

Note: It is noted that since the GRID entry is controlled with the Nodes filter, the grid.ps load set with the permanent single point constraint data is also controlled by the Nodes filter. 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 for assigning entity IDs and stuffing the Patran database when reading

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an MSC Nastran input file.

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Table 4-9 Entity Label Offset Definition Item

Description

Input Offset Value

Highlight a cell or cells under the Offset/Maximum column of the spreadsheet. To select the entire column, click on the column header. Then enter that offset value in this data box and press Enter or Return to set the offset value. You may also enter the word Auto (see Automatic Offset below).

Automatic Offset

With a cell or cells selected in the Offset/Maximum column, pressing this button sets those cells to Auto, meaning that the offset if determined automatically by the highest ID already existing in the database. This is the default.

Offset Labels

ID can be offset for the following entities: Nodes, Elements, Materials, Properties, Coordinates, Loads, Subcases, and MPCs. This does not apply to Comment Lines. Setting the Offset/Maximum for Comment Lines to Auto or 0 allows for import of all comment lines and unrecognized entities. Setting this it a negative number disables all import of comment lines and unrecognized entities. Setting this to a positive number limits the number of comment lines to the specified values. Unrecognized entities are still imported as DTI (Direct Text Input).

Minimum Maximum

These columns simply show the Minimum and Maximum IDs currently found in the Patran database.

Offset/Maximum

This is the ID offset value to be used during import. The new ID value is the ID found in the MSC Nastran input file plus this offset value.

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All references to IDs in the input file are also offset. If a node references a particular CID as its analysis frame, then the reference is offset as well. If the coordinate frame is defined in the same input file, the proper references should be maintained. The preference is 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 is 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.

Chapter 4: Supported Entities MSC Nastran Input File Import

Summary Data Form This form appears after import of the MSC 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 is not yet committed to the Patran database, and can be undone. However, the next database operation commits the import to the database and no undone can be issued after that. If there is any question as to whether or not this import was desired, review the graphics data prior to performing any operation that issues a database operation. If the import was not correct, select the undo button on the main menu bar.

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Reject Card Form During import of the MSC Nastran input file, some entries types might not be understood by Patran. Those entries are brought into Patran in the Direct Text Input (DTI) 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.) Entries 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 have no characters in front of the command name. Commands preceded by the character $> are used to allow processing of comment lines. Note: Rejected entries 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 entries are placed back into the input deck when it is written out again. See Direct Text Input, 312. Data

Translation Notes This section describes specifics about 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 an input file into Patran. All non-supported entries are sent to the appropriate Direct Text Input (DTI) 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 is 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) are still 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

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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.

Conflict ID 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 are asked if you want the ID of the new definition offset. If you select YES, a new ID is chosen. If you select YES FOR ALL, a new ID is chosen for this definition, as well as for any others found to be in conflict. In this case, all references to the ID in the original Patran database still reference the old ID, but references to the ID from within the input file are altered to reference the new ID. If you do not want the ID to be offset, then you are 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 are referencing the same ID. The definition for that ID are 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.

Coordinate Systems

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References to GRIDs on CORD1C,CORD1R, and CORD1S are lost. The locations of the referenced GRIDs are extracted, and those locations are used to create the Patran definition.



References to RIDs on CORD2D, CORD2R, and CORD2S 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 input file is created. The definition will be equivalent, but not identical.



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.



Due to limitations in the Patran definitions of coordinate systems, chained 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 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.

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Patran MSC Nastran Preference Guide - Implicit Nonlinear MSC Nastran Input File Import

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 input file is generated.



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-offreedom 2 through 6.



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.

Elements and Element Properties 

Higher order elements (CQUAD8, CTRIA6, CHEXA, CPENTA, CTETRA) generate linear elements in Patran if none of the mid-edge nodes are specified.



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.



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 input file is created, the data remains with the CBAR and CBEAM entries. No BAROR or BEAMOR entries are generated.



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. 

Main Index

Set Name Extensions

Chapter 4: Supported Entities MSC Nastran Input File Import

• 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 are created to define the distinct definitions. The table below defines extensions to the Property Set Names shown in the Table 4-14. 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 are added to the Property Set Name. Element

Field

Extension

CBAR

PA PB

.pa .pb

CBEAM

SA SB PA PB

.sa .sb .pa .pb

CDAMP1/2 CELAS1/2 CMASS1/2

C1 C2

.ca .cb

CGAP, CONM1/2

CID

.c

CONROD

MID

.m

CQUADR/X/4/8 CTRIAR/X/3/8

MCID

.c

MPCs 

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 is 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

Main Index



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 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.

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Supported Model Entities



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.



A job is created during the import. The name of the created job is the base name 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.

Supported Model Entities The following tables summarize all the various MSC Nastran SOL 400 commands, File Management System, Executive and Case Control, and Bulk Data entities, supported by the Patran MSC Nastran application preference for Implicit Nonlinear analysis. See the index to find more information in this manual on how each command is supported. The list is alphabetical order by sections of the MSC Nastran input file. If it is not listed, it is not supported. Only compatible SOL 400 entries are listed. Under the Export/Import columns is listed either YES or NO to indicate support or the generic entity name created on import, e.g. mat.. Table 4-10 Supported NASTRAN and FMS Statements Entry

Export

Import

Comments

NASTRAN SYSTEM (316)=7 YES

YES

For MASTER indexing of results

SYSTEM YES (316)=19

YES

For MASTER/DBALL results

SEGLOG YES

YES

For PENALT default calculation

ASSIGN

NO

NO

Used for restart jobs - not currently supported for SOL 400.

RESTART

NO

NO

Table 4-11 Supported Executive Control Entry

Export

Import

Comments

ECHO

YES

YES

Data deck echo: NONE, SORTED, UNSORTED.

SOL

YES

YES

Set to 400 automatically. Import detects proper solution sequence and sets preference accordingly.

CEND

YES

YES

Written and detected automatically. Indicates end of executive control and start of case control

Main Index

Chapter 4: Supported Entities Supported Model Entities

Table 4-12 Supported Case Control Entry

Export

Import

Comments

ACCELERATION

NO

NO

ANALYSIS

YES

YES

Current support and recognition of STATICS, MODES, BUCK, HSTAT, HTRAN, MTRAN, NLSTATIC and NLTRAN.

AUTOSPC

YES

YES

Used with RESIDUAL keyword automatically.

BCHANGE

NO

NO

BCONTACT used instead.

BCONTACT

YES

YES

Contact table request.

BCMOVE

NO

NO

BCONTACT used instead.

BEGIN BULK

YES

YES

Written automatically. Indicates start of bulk data and end of case control. If importing a partial deck it is recommended to that this statement be present to avoid problems.

BOUTPUT

YES

YES

Contact output request.

BSQUEAL

YES

NO

Brake squeal analysis request.

CMETHOD

NO

NO

Complex eigenvalue extraction request - not supported.

DISPLACEMENT

YES

YES

Displacement output request.

ENTHALPY

YES

YES

Enthalpy vector output request.

ESE

YES

YES

Element strain energy output request.

FLUX

YES

YES

Thermal flux output request.

FORCE

YES

YES

Element force output request.

FREQUENCY

NO

NO

Forcing frequency set request - not supported.

IC

YES

YES

Transient initial condition load set request.

INCLUDE

NO

YES

Supported only via DTI on export.

HDOT

YES

YES

Rate of change of enthalpy output request.

GPFORCE

YES

YES

Grid point force output request.

GPSTRESS

YES

YES

Grid point stress output request.

LABEL

YES

YES

LOAD

YES

YES

Load set request.

METHOD

YES

YES

Standard eigenvalue extraction request.

MPC

NO

NO

MPC set request.

MPCFORCES

YES

YES

MPC force output request.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Supported Model Entities

Table 4-12 Supported Case Control Entry

Export

Import

Comments

NLIC

NO

NO

Nonlinear initital condition for perturbation load step. Since this is not directly supported, by default uses last increment of previous STEP.

NLLOAD

YES

YES

Nonlinear load output request.

NLPARM

YES

YES

Nonlinear parameter selection.

NLRESTART

NO

NO

Restart parameters - not supported.

NLSTEP

YES

YES

Load stepping procedure.

NLSTRESS

YES

YES

Nonlinear stress output request.

OLOAD

YES

YES

Applied force output request.

OFREQUENCY

NO

NO

Frequency set output request.

OUTPUT(POST)

YES

YES

Used for grid point stress output.

SDAMPING

YES

NO

Structural Damping Selection.

SET

YES

YES

Written and recognized on import as necessary for supporting entities.

SMETHOD

YES

NO

Solver request.

SPC

YES

YES

Constraint set request.

SPCFORCES

YES

YES

Constraint/reaction force output request.

STEP

YES

YES

Load step start - written automatically.

STRAIN

YES

YES

Element strain output request.

STRESS

YES

YES

Element stress output request.

STRFIELD

YES

YES

Grid point stress output request.

SUBCASE

YES

YES

Subcase start - written automatically.

SUBSTEP

NO

NO

Coupled analysis not currently supported.

SUBTITLE

YES

YES

SURFACE

YES

YES

Used for grid point stress output request.

TEMPERATURE

YES

YES

Temperature load set request.

THERMAL

YES

YES

Temperature output request.

TITLE

YES

YES

TSTEP

YES

YES

Linear time stepping selection.

TSTEPNL

NO

NO

Nonlinear time stepping selection. NLSTEP used instead.

UNGLUE

NO

NO

Contact body unglue selection - uses BCONTACT instead.

Main Index

Chapter 4: Supported Entities Supported Model Entities

Table 4-12 Supported Case Control Entry

Export

Import

VCCT

YES

YES

VECTOR

YES

YES

VELOCITY

NO

NO

VOLUME

YES

YES

Comments Alternate form of DISPLACEMENT request - used for modal and buckling analysis. Used for grid point stress output request.

Table 4-13 Supported Parameters Entry

Export

Import

Comments

CHECKOUT

YES

YES

Checkout run.

COUPMASS

YES

YES

Requests the generation of coupled or lumped mass matrix for elements

G

YES

NO

Global structural damping.

GRDPNT

YES

YES

Grid point weight generator.

LGDISP

YES

YES

Large displacements.

PRTMAXIM

YES

NO

Prints maximums. Written automatically.

NOCOMPS

YES

YES

Composite element ply stresses.

POST

YES

YES

To specify OUTPUT2 file request.

RESVEC

YES

YES

Residual Vector Computation.

TSTATIC

NO

NO

W3 and W4

YES

YES

Damping matrix for transient analysis.

WTMASS

YES

YES

Mass matrix multiplier.

Table 4-14 Bulk Data Supported Entities

Entry

Export

Import / Property Set Name

Comments

BAROR

NO

YES

Export places data on CBAR entries.

BCBDPRP

YES

YES

Contact body parameters.

BCBMRAD

YES

YES

Beam contact radius.

BCBODY

NO

YES

Exports as BCBODY1.

BCBODY1

YES

YES

Contact body definition.

BCBZIER

NO

YES

Rigid contact Bezier surface. Defines geometry.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Supported Model Entities

Table 4-14 Bulk Data Supported Entities

Entry

Export

Import / Property Set Name

Comments

BCHANGE

YES

YES

Contact body exclusions and definitions.

BCMOVE

YES

YES

Defines movement of contact bodies.

BCNURB2

YES

YES

Refines rigid body. Derived from geometry.

BCNURBS

YES

YES

Refines rigid body. Derived from geometry.

BCONECT

YES

YES

Defines contact pairs.

BCONPRG

YES

YES

Geometric contact pair parameters.

BCONPRP

YES

YES

Physical contact pair parameters.

BCONUDS

NO

NO

User defined contact body service/subroutine.

BCPARA

YES

YES

Contact parameters.

BCPATCH

YES

YES

Rigid body definition made up of patches (elements).

BCPROP

YES

YES

Contact body properties.

BCRIGID

YES

YES

Rigid contact body definition.

BCRGSRF

YES

YES

Rigid body surfaces.

BCTABL1

YES

YES

Contact table definition.

BCTABLE

NO

YES

Exports as BCTABL1. See BCTABL1.

BCTRIM

YES

YES

Trimming curves used to define rigid bodies via nurbs.

BEAMOR

NO

YES

Export places data on CBEAM entries.

BLSEG

YES

YES

Contact boundary lines or segments.

BOLT

YES

YES

Overclosure MPCs

BSQUEAL

YES

YES

Break squeal analysis data.

BSURF

YES

YES

Contact body surface definition by element.

CBAR

YES

YES

See PBAR or PBARL. Orientation and offset vectors are redefined in global cartesian during import.

CBARAO

NO

YES

On import, new property sets are created for each occurrence of a CBAR entry referenced by a CBARAO entry.

CBEAM

YES

YES

See PBEAM or PBEAML. Orientation and offset vectors are re-defined in global cartesian during import.

CBEND

NO

NO

CBUSH

YES

YES

See PBUSH and PBUSHT.

CBUSH2D

YES

YES

See PBUSH2D

CDAMP1

YES

YES

See PDAMP.

Main Index

Chapter 4: Supported Entities Supported Model Entities

Table 4-14 Bulk Data Supported Entities

Entry

Export

Import / Property Set Name

Comments

CDAMP2

YES

YES

Scalar damper and properties. See PDAMP.

CDAMP3

NO

YES

Treated as component 1 (X translation) CDAMP1.

CDAMP4

NO

YES

Treated as component 1 (X translation) CDAMP1.

CELAS1

YES

YES

See PELAS.

CELAS2

YES

YES

Scalar spring element and properties. See PELAS.

CELAS3

NO

YES

Treated as component 1 (X translation) CELAS1.

CELAS4

NO

YES

Treated as component 1 (X translation) CELAS1.

CFAST

YES

YES

See PFAST. Fastener connector.

CGAP

YES

YES

See PGAP. Orientation and offset vectors are re-defined in global cartesian during import.

CHBDYG

YES

YES

See PHBDY. Geometric surface element definition - grid form.

CHBDYP

YES

YES

See PHBDY. Geometric surface element definition property form.

CHEXA

YES

YES

See PSOLID or PCOMPLS.

CIFHEX

YES

YES

Cohesive zone solid hexa element. See PCOHE.

CIFPENT

YES

YES

Cohesive zone solid penta element. See PCOHE.

CIFQDX

YES

YES

Cohesive zone 2D solid axisymmetric element. See PCOHE.

CIFQUAD

YES

YES

Cohesive zone 2D solid planar element. See PCOHE.

CMASS1

YES

YES

See PMASS.

CMASS2

YES

YES

Scalar mass element and properties. See PMASS.

CMASS3

NO

YES

Treated as component 1 (X translation) CMASS1.

CMASS4

NO

YES

Treated as component 1 (X translation) CMASS1.

CONM1

YES

conm1

Concentrated mass element - general form.

CONM2

YES

conm2

Concentrated mass element - rigid body form.

CONROD

YES

conrod

Rod element and properties.

CONV

YES

conv.

Free convection boundary condition.

CONVM

YES

convm.

Forced convection boundary condition.

CORD1C

NO

YES

CORD1R

NO

YES

CORD1S

NO

YES

On import, references to GRIDs on these entries are lost. The locations of the referenced GRIDs are extracted, and those locations are used to create the Patran definition.

Main Index

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Patran MSC Nastran Preference Guide - Implicit Nonlinear Supported Model Entities

Table 4-14 Bulk Data Supported Entities

Entry

Export

Import / Property Set Name

Comments

CORD2C

YES

YES

CORD2R

YES

YES

CORD2S

YES

YES

CPENTA

YES

YES

See PSOLID or PCOMPLS.

CQUAD4

YES

YES

See PSHELL or PCOMP/G or PLPLANE.

CQUAD8

YES

YES

See PSHELL or PCOMP/G or PLPLANE.

CQUADR

YES

YES

See PSHELL or PCOMP/G.

CQUADX

YES

YES

See PLPLANE or PLCOMP.

CREEP

NO

NO

Creep material properties.

CROD

YES

YES

See PROD.

CSHEAR

YES

YES

See PSHEAR.

CTETRA

YES

YES

See PSOLID or PCOMPLS.

CTRIA3

YES

YES

See PSHELL or PCOMP/G.

CTRIA6

YES

YES

See PSHELL or PCOMP/G.

CTRIAR

YES

YES

See PSHELL or PCOMP/G.

CTRIAX

YES

YES

See PLPLANE or PLCOMP.

CTUBE

NO

NO

CVISC

YES

YES

See PVISC.

CWELD

YES

YES

See PWELD.

DAREA

NO

NO

DLOAD

YES

NO

DPHASE

NO

NO

EIGB

YES

YES

Eigenvalue extraction for buckling analysis.

EIGC

NO

NO

Eigenvalue extraction for complex modal analysis.

EIGR

YES

YES

Eigenvalue extraction for modal analysis.

EIGRL

YES

YES

Lanzcos eigenvalue extraction for modal or buckling analysis.

ELEMUDS

NO

NO

User defined element property service/subroutine.

FORCE

YES

force.

Concentrated force.

FORCE1

NO

YES

Exports as FORCE.

FORCE2

NO

YES

Exports as FORCE.

Main Index

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 input file is created. The definition will be equivalent, but not identical.

Dynamic Load Combination or Superposition.

Chapter 4: Supported Entities Supported Model Entities

Table 4-14 Bulk Data Supported Entities

Entry

Export

Import / Property Set Name

Comments

FREQ

NO

NO

FREQ1

NO

NO

FREQ2

NO

NO

FREQ3

NO

NO

FREQ4

NO

NO

FREQ5

NO

NO

GENUDS

NO

NO

User data for notify user defined service/subroutine.

GRAV

YES

grav.

Acceleration body loading.

GRDSET

NO

YES

Data written to GRID entries on export.

GRID

YES

YES

SEID field not supported. The CD and CP references are both maintained. The PS data is used to create a constraint set.

IPSTRAIN

YES

NO

Initial plastic strain.

ISTRESS

YES

NO

Initial stress.

LOAD

YES

YES

This entry is used in creating load cases in Patran, but the SID of this entries is lost. The SIDs on the individual FORCE, MOMENT, GRAV, PLOADx, RFORCE, and TEMPx entries are used in creating the names of the load sets.

LSEQ

YES

YES

Static load sets.

MAT1 MATT1

YES

mat1.

The MCSID field is not currently supported. If the G field is blank in the input file, the MSC Nastran default value is filled in during import. Creates Isotropic, linear elastic constitutive model.

MAT2 MATT2

YES

mat2.

The MCSID field is not currently supported. Creates 2D Anisotropic, linear elastic constitutive model.

MAT3 MATT3

YES

mat3.

Creates 2D Orthotropic, linear elastic constitutive model.

MAT4 MATT4

YES

YES

Imports as part of a linear elastic constitutive models

MAT5 MATT5

YES

YES

Imports as part of a linear elastic constitutive models

Main Index

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Table 4-14 Bulk Data Supported Entities

Entry

Export

Import / Property Set Name

Comments

MAT8 MATT8

YES

mat8.

Creates 2D Orthotropic, linear elastic constitutive model.

MAT9 MATT9

YES

mat9.

Creates 3D Anisotropic, linear elastic constitutive model.

MATEP MATTEP

YES

YES

Creates Elastoplastic constitutive models under primary MAT1, MAT2, MAT3, MAT8, MAT9, MATORT materials

MATF MATTF

YES

YES

Creates Failure constitutive models under primary MAT1, MAT2, MAT3, MAT8, MAT9, MATORT materials.

MATG

YES

YES

Created as part of a Gasket element property.

MATTG

NO

NO

MATHE / MATTHE

YES

mathe.

Creates Hyperelastic material model.

MATHED

NO

NO

Hyperelastic damage model.

MATHP

NO

YES

Writes MATHE on export.

MATORT / MATTORT

YES

matort.

Creates 3D Orthotropic, linear elastic constitutive model.

MATS1

YES

YES

Creates Nonlinear Elastic constitutive models under primary MAT1 materials. Use MATEP for elastoplastic definition.

MATUDS

NO

NO

Material user defined service/subroutine.

MATUSR / MATTUSR

NO

NO

Hypoelastic & user defined material model.

MATVE / MATTVE

NO

NO

Viscoelastic material model.

MATVP

YES

YES

Create Viscoplastic constitutive models under primary MAT1, MAT2, MAT3, MAT8, MAT9, and MATORT materials. Only MATVP coefficients format is supported (Coefficient A should be other than 1.0/0.0).

MCOHE

YES

YES

Cohesive zone material properties.

MDLPRM

YES

NO

BRTOBM and OFFDEF support on export.

MOMENT

YES

moment.

Concentrated moment.

MOMENT1

NO

YES

Exports as MOMENT.

MOMENT2

NO

YES

Exports as MOMENT.

MPC

NO

NO

Explicit multipoint constraint.

MPCADD

NO

NO

Main Index

Chapter 4: Supported Entities Supported Model Entities

Table 4-14 Bulk Data Supported Entities

Entry NLMOPTS

Export YES

Import / Property Set Name YES

Comments Nonlinear Multiple Options. “CREEP” Keyword indicates that the formulation for creep analysis is supported only for Implicit Creep options.

NLPARM

NO

YES

Exports as NLSTEP.

NLPCI

NO

NO

Use NLSTEP instead.

NLSTEP

YES

YES

Convergence criteria, step size control, and numerical procedure for time/load stepping.

NSM

NO

YES

NSM1

NO

YES

NSML1

NO

YES

PARAM

YES

YES

Limited set of PARAMs supported. See Table 4-13.

PBAR

YES

pbar.

See CBARAO. Bar physical properties.

PBARL

YES

pbarl.

See CBARAO. Bar dimension properties.

PBARN1

YES

YES

Nonlinear PBAR/PBARL property extension.

PBCOMP

YES

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.

Exported with element definition.

The SO field is not currently supported. A YES is provided automatically when a new input file is created. Only the lumped areas definition is understood, If a uniform cross section is defined here, it is converted to a lumped area definition, but no lumped areas is defined. PBEAM

YES

pbeam.

Beam physical properties.

PBEAML

YES

pbeaml.

Beam dimension properties.

PBEMN1

YES

YES

Nonlinear PBEAM/PBEAML property extension.

PBEND

NO

NO

PBMSECT

YES

pbmsect

Arbitrary beam section properties.

PBRSECT

YES

pbrsect

Arbitrary bar section properties.

PBUSH

YES

pbush. pbush_g.

Generalized spring-damper property. Imprted property name dependent on connectivity: two nodes or grounded.

Main Index

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Table 4-14 Bulk Data Supported Entities

Entry

Export

Import / Property Set Name

Comments

PBUSH2D

YES

pbush2d.

2-D linear/nonlinear spring/damper properties.

PBUSHT

YES

pbusht_1D.

Frequency dependent, nonlinear spring/damper property.

PCOHE

YES

YES

Cohesive zone element properties.

PCOMP

YES

pcomp. pcompr.

Composite ply shell elements. The SB and FT fields are not read. The created property name is dependent on associated element type.

PCOMPG

YES

pcomp. pcompr.

Composite ply shell elements with global layers. The SB and FT fields are not read. The created property name is dependent on associated element type.

PCOMPLS

YES

pcompls.

Solid composite elements.

PCONV

YES

YES

See CONV.

PCONVM

YES

YES

See CONVM.

PDAMP

YES

pdamp. pdamp_g. cdamp2 cdamp2_g

Scalar damping properties. Imported property name dependent on associated element type and element connectivity: two nodes or grounded.

PELAS

YES

pelas. pelas_g. celas2 celas2_g

Scalar spring properties. Imported property name dependent on associated element type and element connectivity: two nodes or grounded.

PFAST

YES

pfast.

Fastener connector property.

PGAP

YES

pgap. pgap_a.

Gap properties. Imported property name dependent on nonadaptive or adaptive setting.

PHBDY

YES

YES

The BDYOR entry that may contain default values for CHBDY elements is not currently supported.

PLCOMP

YES

plcomp.

2D solid planar composite elements.

PLOAD1

YES

pload1.

Uniform distributed load on bar elements. 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 is ignored, and a message is presented indicating the problem.

PLOAD2

YES

pload2.

Static pressure on shell elements.

PLOAD4

YES

pload4.

Face pressure on solid element. Only pressure loads normal to the surface can be imported. If a surface traction is detected, it will be ignored, and a message is presented indicating the problem.

PLOADX1

YES

ploadx1.

Surface traction on axisymmetric elements.

Main Index

Chapter 4: Supported Entities Supported Model Entities

Table 4-14 Bulk Data Supported Entities

Entry

Export

Import / Property Set Name

Comments

PLPLANE

YES

plplane.

Plane strain/stress/axisymmetric elements.

PMASS

YES

pmass. pmass_g. cmass2 cmass2_g

Concentrated mass properties. Imported property name dependent on associated element type and element connectivity: two nodes or grounded.

PROD

YES

prod.

Rod element property.

PSHEAR

YES

pshear.

Shear element property.

PSHEARN

YES

YES

Nonlinear shear element property extension associated with PSHEAR.

PSHELL

YES

pshell. pshellr.

Imported property name dependent on associated element type.

PSHLN1

YES

YES

Shell element nonlinear property extension associated with PSHELL.

PSHLN2

YES

YES

Plane strain/stress/axisymmetric element nonlinear property extension associated with PLPLANE.

PSLDN1

YES

YES

Solid element nonlinear property extension associated with PSOLID.

PSOLID

YES

psolid.

Solid element properties.

PTUBE

NO

NO

PVISC

YES

pvisc.

Viscous damping elements.

PWELD

YES

pweld.

Weld connector element properties.

QBDY1-4

YES

qbdyi.

Uniform heat flux into elements.

QHBDY

YES

qhbdyi.

Uniform heat flux into nodes.

QVECT

YES

qvect.

Thermal vector flux.

QVOL

YES

qvol.

Rate of volumetric heat.

RADBC

NO

NO

RADCAV

NO

NO

RADM

NO

NO

RADMT

NO

NO

RBAR

NO

NO

RBE1

NO

NO

RBE2

YES

YES

Creates RBE2 MPCs

RBE3

YES

YES

Creates RBE3 MPCx

Main Index

425

426

Patran MSC Nastran Preference Guide - Implicit Nonlinear Supported Model Entities

Table 4-14 Bulk Data Supported Entities

Entry RFORCE

Export YES

Import / Property Set Name rforce.

Comments Rotational angular velocity or acceleration . If the G point is not at the origin of the referenced CID, a new CID will be created and referenced. The METHOD field is not read. It is automatically set to 1 when writing a new file.

RJOINT

NO

NO

RLOAD1

NO

NO

RLOAD2

NO

NO

RROD

NO

NO

RSPLINE

NO

NO

RSSCON

NO

NO

RTRPLT

NO

NO

SET1

YES

YES

Node or element set written or accesses as necessary to support associated entities.

SLOAD

YES

sload.

Concentrated nodal heat source load.

SPC

YES

spc.

Enforced displacements.

SPCADD

YES

YES

This entry is used in creating load cases in Patran, but the SID of this entry is lost on import. The SIDs on the individual SPCx entries are used in creating the names of the load sets.

SPC1

YES

spc1.

Displacement constraints.

SPCD

YES

spcd.

The required SPC or SPC1 entries for the same Degree-ofFreedom are removed from the load case when an SPCD is found. They are automatically be re-generated when a new input file is created.

SPCR

YES

spcr.

Relative enforced displacement.

SPOINT

YES

YES

Treated as GRIDS at the global origin on import. 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. Exported as necessary.

SUPORT

NO

NO

Fictitious support.

SUPORT1

NO

NO

Fictitious support.

Main Index

Chapter 4: Supported Entities Supported Model Entities

Table 4-14 Bulk Data Supported Entities

Entry

Export

Import / Property Set Name

Comments

TABDMP1

YES

NO

Modal damping.

TABLED1

YES

Field.

Time dependent load data - in general.

TABLED2

NO

Field.

Converted to an equivalent TABLED1 when read

TABLED3

NO

Field.

Converted to an equivalent TABLED1 when read

TABLEM1

YES

Field.

Temperature dependent material data.

TABLEM2

NO

Field.

Converted to an equivalent TABLEM1 when read

TABLEM3

NO

Field.

Converted to an equivalent TABLEM1 when read

TABLEM4

NO

Field.

Converted to an equivalent TABLEM1 when read

TABLES1

YES

Field.

Stress versus strain data - in general.

TABLEST

YES

Field.

Temperature dependent stress-strain data.

TABSCTL

YES

YES

Load step control table.

TEMP

YES

temp.

Temperature loading.

TEMPD

YES

YES

Default temperature assignment.

TEMPP1

YES

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

YES

temprb.

Only the average temperature and effective linear gradient data fields are used. The specified temperatures at the stress recovery locations are ignored.

TIC

NO

NO

Transient initial conditions.

TLOAD1

YES

YES

Transient response dynamic load or enforced motion.

TLOAD2

NO

YES

Exports as TLOAD1.

TSTEP

YES

YES

Linear time stepping selection.

TSTEPNL

NO

NO

See NLSTEP.

UDSESV

NO

NO

User defined state variables.

VCCT

YES

YES

Virtual crack closure technique.

VIEW

NO

NO

VIEW3D

NO

NO

Main Index

Radiation cavity and view factor calculation.

427

428

Patran MSC Nastran Preference Guide - Implicit Nonlinear Files Created

Files Created 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 is replaced with the jobname assigned by the user. File Name

Main Index

Description

*.db

This is the Patran database. During an analyze pass, model data is read from this database and, during a Access 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 MSC Nastran input file created by the interface. This file typically resides in the current directory.

jobname.op2

This is the MSC Nastran OUTPUT2 file, which is read by the Access Results pass. This file typically resides in the current directory and contains results data. It is created by placing a PARAM,POST,1 in the bulk data section of the input file.

jobname.MASTER jobname.DBALL

These are the MSC Nastran MASTER/DBALL database files, which are read by the Access Results pass. These files typically resides in the current directory or directory where the run was performed and contains results and model data. It is created by placing the line NASTRAN SYSTEM(316)=19 or 7 in the input file before the FMS and Executive sections of the input file.

jobname.f04 jobname.f06 jobname.log jobname.sts

These are MSC Nastran text output files. Check these files for correct execution of MSC Nastran.

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 script file run on Linux only, 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.

MSC.Fatigue Quick Start Guide

Index Patran MSC Nastran Preference Guide-Implicit Nonlinear

Symbols , 55

Index

Numerics

1D- Grounded Bush/Bush (CBUSH2D/PBUSH2D), 131 3D - Body Pair- Geometric, 201 3D - Body Pair- Physical, 204

A

abort job, 288 absorptivity, 236 ACCELERATION, 372, 415 acceleration, 210, 218 accelerations, 372 ambient temperature, 240, 241, 242 ANALYSIS, 415 MODES, 324, 327 MTRAN, 330 NLSTATICS, 322 NLTRAN, 330 STATICS, 322 analysis abort, 288 code, 2 coordinate frame, 43 create, 277 delete, 284 demo, 290 import, 282 monitor, 285 preference, 2 results, 280 type, 2 analysis job definition, 279 analysis job submittal, 279 analyze, 276 anisotropic, 52

Main Index

applied heat, 211 directional fluxes, 235 nodal source, 237 normal fluxes, 234 total heat, 238 volumetric generation, 238 applied loads, 372, 374 arbtitrary beam section, 103, 111 Arruday-Boyce, 77 ASSIGN, 414 augmentation, 308 AUTOSPC, 300, 415

B

Barlat, 64 BAROR, 417 BCBDPRP, 247, 256, 257, 417 BCBMRAD, 106, 119, 417 BCBODY, 417 BCBODY1, 246, 256, 417 BCBZIER, 417 BCHANGE, 248, 252, 253, 415, 418 BCMOVE, 349, 415, 418 BCNURB2, 418 BCNURBS, 256, 418 BCONECT, 418 BCONPRG, 202, 263, 346, 349, 418 BCONPRP, 205, 263, 346, 350, 418 BCONTACT, 263, 346, 415 BCONUDS, 418

430 Patran MSC Nastran Preference Guide-Implicit Nonlinear

BCPARA, 418 AUGDIST, 309 AUGMENT, 309 BEAMB, 305 BIAS, 305 ERROR, 305 FTYPE, 308 ICSEP, 306 MAXSEP, 306 METHOD, 303, 308 NLGLUE, 305 PENALT, 309 SEGSYM, 308 SLDMT, 308 STKSLP, 309 TAUGMNT, 309 TPENALT, 309 BCPATCH, 418 BCPDPRP, 251 BCPROP, 418 BCRGSRF, 418 BCRIGID, 256, 418 BCTABL1, 418 BCTABLE, 310, 418 BCTRIM, 256, 418 BDBDPRP ISTYP, 303 beam offsets, 104 BEAMOR, 418 BEGIN BULK, 415 BLSEG, 248, 249, 418 BOLT, 45, 49, 418 BOUTPUT, 372, 374, 415 brake squeal, 356 breaking glue, 352 BSQUEAL, 356, 415, 418 BSURF, 246, 418 bulk data, 417 bulk data file, 401

C

case control, 415 CBAR, 101, 107, 418 CBARAO, 101, 107, 418 CBEAM, 108, 110, 113, 116, 117, 418 CBEND, 418

Main Index

CBUSH, 99, 128, 418 CBUSH2D, 418 CDAMP1, 96, 98, 121, 127, 293, 418 CDAMP2, 96, 98, 121, 127, 293, 419 CDAMP3, 419 CDAMP4, 419 CELAS1, 94, 97, 120, 126, 293, 419 CELAS2, 94, 97, 120, 126, 293, 419 CELAS3, 419 CELAS4, 419 CEND, 414 CFAST, 133, 419 CGAP, 123, 419 CGI, 232 Chaboche, 65 CHBDYG, 234, 235, 419 CHBDYP, 234, 235, 419 CHBDYP,PHBDY, 239 CHECKOUT, 417 CHEXA, 188, 191, 192, 196, 197, 199, 419 CID Distributed Load, 211 CID distributed load, 226 CIFCDX, 77 CIFHEX, 77, 201, 419 CIFPENT, 77, 201, 419 CIFQDX, 179, 419 CIFQUAD, 77, 166, 172, 419 CIFQUAD4/8, 166 CMASS1, 92, 125, 293, 419 CMASS2, 92, 125, 293, 419 CMASS3, 419 CMASS4, 419 CMETHOD, 415 Cohesive, 53, 77 combined hardening rule, 65 composite, 53, 80 CONM1, 91, 419 CONM2, 93, 419 CONROD, 118, 293, 419 constitutive model status, 54 constitutive models, 51 elastoplastic, 51, 62 failure, 51, 72 linear elastic, 51, 55 nonlinear elastic, 51, 61

INDEX 431

constraints, 372 contact, 211 advanced, 352 augmentation, 308 bondary options, 354 control parameters, 302 detection, 305 friction, 307 geometric properties, 201 initial, 310 physical properties, 204 results, 372, 374 separation, 306 sliding, 307 contact bodies, 244 deformable surfaces defining in MSC.Patran, 246, 250, 251, 253, 254 rigid surface defining in MSC.Patran, 255 Contact Table, 304 contact table, 263, 345, 346 control nodes, 213 CONV, 239, 419 convection, 211 coupled, 241 to ambient, 239 CONVM, 419 coordinate frames, 42 analysis, 43 reference, 43 coordinates, 293 CORD1C, 419 CORD1R, 419 CORD1S, 419 CORD2C, 42, 420 CORD2R, 42, 420 CORD2S, 42, 420 COUPMASS, 417 Cowper-Symonds, 66 CPENTA, 188, 420 CQUAD4, 136, 142, 144, 149, 153, 155, 157, 161, 163, 167, 168, 169, 171, 176, 182, 420 CQUAD8, 136, 149, 155, 157, 161, 163, 167, 169, 171, 176, 182, 420

Main Index

CQUADR, 139, 146, 151, 159, 164, 184, 420 CQUADX, 173, 177, 178, 180, 181, 420 crack (VCCT), 229 CREEP, 420 Creep, 322 CROD, 118, 293, 420 CSHEAR, 186, 420 CTETRA, 188, 191, 194, 420 CTRIA3, 136, 142, 144, 149, 157, 161, 165, 182, 420 CTRIA6, 136, 149, 157, 161, 169, 182, 420 CTRIAR, 139, 146, 151, 159, 164, 184, 420 CTRIAX, 420 CTUBE, 420 CVISC, 420 CWELD, 420

D

DAREA, 420 Define Damping, 361 Define Time Step, 360 degrees-of-freedom, 45 delete results attachment, 281, 391 demo, 290 direct text input, 279, 298, 312, 313, 317, 318 DISPLACEMENT, 372, 415 displacement, 210, 218 displacements, 372 distributed load, 211, 225, 226 DLOAD, 420 DPHASE, 219, 220, 420

E

ECHO, 292, 414 EIGB, 327, 420 EIGC, 420 eigenvectors, 372 EIGR, 324, 358, 420 EIGRL, 324, 327, 358, 420 elastoplastic, 51, 62

432 Patran MSC Nastran Preference Guide-Implicit Nonlinear

elements, 42, 44 2D linear/nonlinear bush, 131 2d solid, 161 axisymmetric gasket, 180 axisymmetric solid, 173 axisymmetric solid with twist, 176 bush, 128 capacitor, 127 conductor, 126 coupled point mass, 91 fastener connector, 133 gap, 123 general beam, 113 general section beam, 101 general section rod, 118 grounded bush, 99 grounded capacitor, 98 grounded conductor, 97 grounded scalar damper, 96 grounded scalar mass, 92 grounded scalar spring, 94 incompressible axisymmetric solid, 177 incompressible plane strain solid, 164 laminate axisymmetric solid, 179 laminate plane strain solid, 166 linear cubic closed section beam, 107 linear shear beam, 107, 117 linear/cubic closed section beam, 116 linear/cubic open section beam, 116 lumped area beam, 108 lumped point mass, 93 plane strain gasket, 167 plane stress solid, 169 reduced axisymmetric solid, 175 reduced integration thick shell, 154 reduced plane strain solid, 163 reduced plane stress solid, 171 revised bending panel, 159 revised equivalent section plate, 150 revised homogeneous plate, 139 revised laminate plate, 146 revised membrane, 184 revised plane strain solid, 164 scalar damping, 121 scalar mass, 125 scalar spring, 120

Main Index

shear panel, 185 solid, 188 solid gasket, 199 solid incompressible, 194 solid laminate, 195, 197 solid reduced integration, 190 solid shell, 192 solid standard formulation, 188 spot weld connector, 132 standard bending panel, 157 standard equivalent section plate, 148 standard formulation thick shell, 152 standard homogeneous plate, 136 standard laminate plate, 143 standard membrane, 182 standard plane strain solid, 161 tapered beam, 110 viscous damper, 122 ELEMUDS, 420 enthalpies, 374 ENTHALPY, 374, 415 Environment Variables ACommand20xx, 393 DRA_NAST_NOVEDRCHK, 393 MSP_NASTRAN_CMD20xx, 393 ESE, 372, 415 executive control, 414

F

failure, 51, 72 files, 428 film node, 213, 240, 242 finite element properties, 81 finite elements, 42 FLUX, 374, 415 fluxes, 211, 234, 235, 237, 238, 374 FMS, 414 foam, 76 FORCE, 220, 226, 227, 228, 372, 373, 415, 420 force, 210, 219 FORCE1, 420 FORCE2, 420 forces, 372 FREQ, 421 FREQ1, 421 FREQ2, 421

INDEX 433

FREQ3, 421 FREQ4, 421 FREQ5, 421 FREQUENCY, 415 friction, 307

G

G, 417 gasket, 167, 180 GC, 232 Gent, 77 Gent model, 80 GENUDS, 421 global variables, 399 glued contact, 352 GPFORCE, 373, 415 GPSTRESS, 373, 415 GRAV, 224, 421 GRDPNT, 417 GRDSET, 421 GRID, 43, 293, 421 grid point force balance, 373 grid point stresses, 373

H

H5NORDOF, 294 hardening rule, 65 hardening slope, 63 Hashin failure criterion, 72 Hashin-fabric failure criterion, 72 Hashin-tape failure criterion, 72 HDF5, 294 HDOT, 374, 415 heat fluxes, 374 heat transfer coefficient, 241, 243 heats of constraints, 374 hill failure criterion, 72 Hill yield, 64 hyperelastic, 52, 74

I

IC, 415 IGROW, 231 import, 282

Main Index

INCLUDE, 298, 312, 415 include file, 298 INCM, 231 increments, 337 inertial load, 223 initial displacement, 225 plastic strain, 228 stress, 228 temperature, 233 velocity, 225 initial conditions, 210 initial contact contact initial, 303 initial load, 210 initial plastic strain, 211 initial stress, 211 initial temperature, 211 input file, 401 introduction, 2 IPSTRAIN, 228, 421 isotropic, 51 isotropic hardening rule, 65 ISTRESS, 229, 421 ITER, 334 iterations, 342 ITYPE, 231

J

Johnson-Cook, 65

K keywords VCCT, 229 kinematic hardening rule, 65 Kumar, 65

L

LABEL, 415 laminate, 53, 80 LGDISP, 417 LOAD, 415, 421 load cases, 243

434 Patran MSC Nastran Preference Guide-Implicit Nonlinear

load steps, 314 buckling, 327 contact table, 263, 345, 346 create, 316 criteria, 340 delete, 319 direct text input, 318 edit, 319 increments, 337 iterations, 342 normal modes, 324 parameters, 320 selection, 383 solvers, 334 static, 322 steady state heat, 332 transient dynamic, 330 transient heat, 333 LSEQ, 421

M

MAT1, 56, 421 MAT2, 59, 421 MAT3, 421 MAT4, 56, 239, 421 MAT5, 58, 59, 60, 61, 421 MAT8, 57, 422 MAT9, 60, 422 MATEP, 62, 422 material properties, 50 anisotropic, 52 composite, 53, 80 elastoplastic, 51, 62 failure, 51, 72 hyperelastic, 52, 74 isotropic, 51 nonlinear elastic, 51, 61 orthotropic, 52 status, 54 MATF, 72, 422 MATG, 168, 181, 199, 422 MATHE, 74, 422 MATHED, 422 MATHP, 422 MATORT, 58, 422 MATS1, 61, 422

Main Index

MATT1, 56, 421 MATT2, 59, 421 MATT3, 421 MATT4, 56, 421 MATT5, 58, 59, 60, 61, 421 MATT8, 57, 422 MATT9, 60, 422 MATTEP, 422 MATTF, 72, 422 MATTG, 422 MATTHE, 422 MATTORT, 58, 422 MATTUSR, 422 MATTVE, 422 MATUDS, 422 MATUSR, 422 MATVE, 422 MATVP, 422 maximum strain failure criterion, 72 maximum stress failure criterion, 72 MCOHE, 77, 422 MCOHE (COHE), 80 MCOHE (CRTOD), 80 MCOHE (EXP), 80 MCOHE (MAXOD), 80 MCOHE (MODEL), 79 MCOHE (RRRD), 80 MCOHE (SFC), 80 MCOHE (SNER), 80 MCOHE (SNSR), 80 MCOHE (VED), 80 MDLPRM, 294, 422 BRTOBM, 293 OFFDEF, 104, 138, 141, 143, 144, 148, 150, 152, 154, 156 METHOD, 232, 415 Mohn-Coulomb, 64 MOMENT, 220, 226, 422 MOMENT1, 422 MOMENT2, 422 monitor job, 285 Mooney, 74 Mooney-Rivlin, 75 motion control, 259 MPC, 415, 422 MPCADD, 422

INDEX 435

MPCFORCES, 373, 415 MSC.Nastran version, 292 multi-point constraints, 44 multipoint constraints, 373

N

NASTRAN, 414 NASTRAN SEGLOG, 303 NLIC, 416 NLLOAD, 373, 416 NLMOPTS, 106, 138, 145, 162, 170, 175, 183, 187, 190, 423 ASSM, 300 TSHEAR, 300 NLPARM, 416, 423 NLPCI, 423 NLRESTART, 416 NLSTEP, 332, 333, 338, 341, 343, 416, 423 NLSTRESS, 373, 416 NOCOMPS, 417 nodes, 42, 43, 293 nonlinear applied loads, 373 nonlinear elastic, 51, 61 nonlinear stresses, 373 NSM, 423 NSM1, 423 NSML1, 423 numbering options, 296

O

OEF1, 395 OES1, 395 OESNL1, 396 OFREQUENCY, 416 Ogden, 76 OGS1, 395 OLOAD, 372, 374, 416 ONRGY1, 397 OPG1, 398 OPHIG, 398 OPNL1, 398 orthotropic, 52 OSTR1, 395, 396 OUGV1, 398 OUTPUT, 416

Main Index

output requests, 362 accelerations, 372 advanced form, 366 applied loads, 372, 374 basic form, 364 constraints, 372 contact, 372, 374 customize defaults, 378 descriptions of, 372 displacements, 372 eigenvectors, 372 enthalpies, 374 fluxes, 374 forces, 372 global edit, 375 grid point force balance, 373 grid point stresses, 373 heats of constraints, 374 multipoint constraints, 373 nonlinear applied loads, 373 nonlinear stresses, 373 rate of change of enthalpies, 374 strain energy, 372 strains, 372 stresses, 373 temperatures, 374 velocities, 373 OUTPUT2, 291 overview, 2

P

parallel processing, 292 PARAM, 423 GRDPNT, 301 WTMASS, 301 PARAM,LGDISP, 300

436 Patran MSC Nastran Preference Guide-Implicit Nonlinear

parameters, 417 brake squeal, 356 buckling, 327 contact augmentation, 308 contact control, 302 contact detection, 305 contact separation, 306 contact table, 263, 345, 346 criteria, 340 friction, 307 increments, 337 initial contact table initial contact, 310 iterations, 342 load step, 320 normal modes, 324 sliding, 307 solvers, 334 static, 322 steady state heat, 332 transient dynamic, 330 transient heat, 333 PBAR, 101, 107, 423 PBARL, 101, 107, 423 PBARN1, 101, 107, 423 PBCOMP, 108, 423 PBEAM, 110, 113, 116, 117, 423 PBEAML, 110, 113, 116, 117, 423 PBEMN1, 110, 113, 116, 117, 423 PBEND, 423 PBMSECT, 110, 113, 423 PBRSECT, 101, 107, 423 PBUSH, 99, 128, 423 PBUSH2D, 424 PBUSHT, 99, 128, 424 PCOHE, 77, 88, 89, 166, 172, 179, 201, 424 PCOMP, 80, 144, 146, 293, 424 PCOMPG, 80, 144, 146, 293, 424 PCOMPLS, 80, 196, 197, 424 PCONV, 239, 424 PCONVM, 424 PDAMP, 96, 98, 121, 127, 424 PELAS, 94, 97, 120, 126, 424 perfectly plastic, 63 perturbation analysis, 36 PFAST, 133, 424

Main Index

PGAP, 123, 424 PHBDY, 234, 235, 424 piecewise-linear strain-rate, 66 plate offsets, 138, 141, 143, 144, 148, 150, 152, 154, 156 PLCOMP, 80, 167, 180, 424 PLOAD1, 225, 226, 227, 228, 424 PLOAD2, 424 PLOAD4, 220, 227, 228, 424 PLOADX1, 220, 424 PLPLANE, 161, 163, 164, 165, 169, 171, 173, 176, 177, 178, 425 PMASS, 92, 125, 425 POST, 417 power law, 65 precision control, 295 preference, 2 pressure, 210, 220 PROD, 118, 425 progressive failure, 72 PRTMAXIM, 417 PSHEAR, 186, 425 PSHEARN, 186, 425 PSHELL, 136, 139, 142, 149, 151, 153, 155, 157, 159, 182, 184, 425 PSHLN1, 136, 142, 153, 155, 425 PSHLN2, 161, 163, 164, 165, 169, 171, 173, 176, 177, 178, 425 PSLDN1, 188, 191, 192, 194, 425 PSOLID, 188, 191, 192, 194, 400, 425 PTUBE, 425 Puck failure criterion, 72 PVISC, 425 PWELD, 425

Q

QBDY1-4, 425 QBDY3, 234 QHBDY, 238, 425 QVECT, 235, 425 QVOL, 57, 58, 59, 60, 61, 238, 425

R

RADBC, 425 RADCAV, 425

INDEX 437

RADM, 235, 425 RADMT, 425 rate of change of enthalpies, 374 rate power law, 65 RBAR, 425 RBE1, 425 RBE2, 45, 46, 425 RBE3, 45, 48, 425 read input file, 282, 401 read results, 280 Real Eigenvalue Extraction, 358 reference coordinate frame, 43 RESTART, 414 results, 280, 390 supported entities, 395 RESVEC, 417 RFORCE, 224, 426 rigid bodies, 259 RJOINT, 426 RLOAD1, 218, 219, 426 RLOAD2, 426 RROD, 426 RSPLINE, 426 RSSCON, 426 RTRPLT, 426 run demo, 290

S

SDAMPING, 416 SEGLOG, 414 select load steps, 383 SET, 416 SET1, 426 SET3, 341 sliding, 307 SLOAD, 426 SMETHOD, 334, 416 smp, 292 SOL, 414 solution parameters, 298 solvers, 334 SPC, 234, 239, 416, 426 SPC1, 219, 426 SPCADD, 426 SPCD, 219, 426

Main Index

SPCFORCES, 372, 416 SPCR, 426 SPOINT, 114, 239, 426 static load cases, 211 STEP, 314, 385, 416 STRAIN, 372, 416 strain energy, 372 strain-rate method, 66 strains, 372 STRESS, 373, 416 stresses, 373 stress-strain curve, 61, 62 STRFIELD, 416 SUBCASE, 314, 385, 416 SUBSTEP, 416 SUBTITLE, 416 SUPORT, 426 SUPORT1, 426 supported entities, 414 SURFACE, 416 surface area, 216 SYSTEM, 294, 393, 414, 428

T

TABCGI, 232 TABDMP1, 362, 427 TABGC, 232 TABLED1, 427 TABLED2, 427 TABLED3, 427 TABLEDi, 218, 219 TABLEM1, 55, 248, 258, 427 TABLEM2, 427 TABLEM3, 427 TABLEM4, 427 TABLES1, 61, 62, 74, 168, 169, 181, 182, 200, 427 TABLEST, 61, 62, 427 TABSCTL, 427 TEMP, 221, 233, 234, 427 TEMPD, 427 TEMPERATURE, 416 temperature, 210, 221 temperature (thermal), 211, 233 TEMPERATURE(INIT), 233

438 Patran MSC Nastran Preference Guide-Implicit Nonlinear

temperatures, 374 TEMPP1, 222, 427 TEMPRB, 222, 427 test data, 74 THERMAL, 374, 416 thermal loads and BCs control nodes, 235, 237, 238, 239 normal heat flux, 234 spatial dependence, 216 surface area, 216 temperature dependence, 217 time dependence, 217 TIC, 225 time dependent load cases, 213 TITLE, 416 TLOAD1, 218, 219 tolerances, 291, 394 Total Load, 227, 228 total load, 211, 227 translation parameters, 291, 394 Tsai-Wu failure criterion, 72 TSTATIC, 417 TSTEP, 416 TSTEPNL, 416

U

UNGLUE, 248, 254, 416

V

VCCT, 229, 417 VECTOR, 372, 417 velocities, 373 VELOCITY, 417 velocity, 210, 218 version, 292 Viscoplastic, 71 VOLUME, 417 von Mises, 64

W

WTMASS, 417

Y

yield functions, 64

Main Index