Copyright 2006 MSC.Software Corporation Linear Static, Normal Modes, and Buckling Analysis Using MSC.Nastran and MSC.Patran May 2006 NAS120 Course Notes Part Number: NA*V2005r3*Z*Z*Z*SM-NAS120-NT1 MSC.Software Corporation Europe MSC.Software GmbH Am Moosfeld Munich, Germany Telephone: (49) (89) Fax: (49) (89) Corporate MSC.Software Corporation 2 MacArthur Place Santa Ana, CA USA Telephone: (800) Fax: (714) Asia Pacific MSC.Software Japan Ltd. Shinjuku First West 8F 23-7 Nishi Shinjuku 1-Chome, Shinjuku-Ku Tokyo , JAPAN Telephone: (81) (3) Fax: (81) (3)
Copyright 2006 MSC.Software Corporation DISCLAIMER 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 2006 MSC.Software Corporation. Printed in U.S.A. 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. MSC, MSC., MSC.Actran, MSC.ADAMS, MSC.Dytran, MSC.EASY5, MSC.Fatigue, MSC.FlightLoads, MSC.Laminate Modeler, MSC.Marc, MSC.Marc Mentat, MSC.Mvision, MSC.Nastran, MSC.Patran, MSC.Robust Design, SimDesigner, SimManager, MSC.SOFY, the MSC.Software corporate logo, and Simulating Reality are trademarks or registered trademarks of the MSC.Software Corporation in the United States and/or other countries. All other brand names, product names or trademarks belong to their respective owners.
Copyright 2006 MSC.Software Corporation TABLE OF CONTENTS SectionPage 1.0Overview Course Objectives ………………………………………………………………………………………………..1-3 What is MSC.Nastran? …………………………………………………………………………………………….1-4 What is MSC.Patran? ……………………………………………………………………………………………..1-7 Case Study: Landing Gear Strut …………………………………………………………………………………1-10 Training and Support ……………………………………………………………………………………………… Introduction to the Finite Element Method Engineering Methods …………………………………………………………………………………………… What is the Finite Element Method ………………………………………………………………………………2-7 Key Concepts in FEM …………………………………………………………………………………………… FEM References ………………………………………………………………………………………………… Basics of MSC.Nastran and MSC.Patran Patran GUI …………………………………………………………………………………………………………..3-3 Patran-Nastran Workflow and Files ………………………………………………………………………………3-19 The Nastran Input File …………………………………………………………………………………………… Case Study: Stadium Arched Roof Truss MSC.Nastran Element Library ………… ……………………………………………………………………… The CROD Element ……………………………………………………………………………………………….4-19 Post Processing CROD Results ………………………………………………………………………………… Case Study: Space Station Truss Introduction to Geometry ………………… ………………………………………………………………………5-6 Coordinate Systems ……………………………………………………………………………………………….5-33 Grid Points ………………………………………………………………………………………………………….5-47 The CBAR Element ……………………………………………………………………………………………….5-66 Multiple Subcases …………………………………………………………………………………………………5-139 Post Processing CBAR Results ………………………………………………………………………………….5-146
Copyright 2006 MSC.Software Corporation TABLE OF CONTENTS SectionPage 6.0Case Study: Traffic Signal Pole Curve Geometry ……………………………………………………………………………………………………6-8 Material Properties …………………… ………………………………………………………………………… The CBEAM Element ………………………………………………………………………………………………6-30 Fields ……………………………………………………………………………………………………………… Post Processing CBEAM Results ……………………………………………………………………………… Case Study: Aircraft Wing Rib Surface Geometry ………………………………………………………………………………………………….7-9 Meshing Surface Geometry ……………………………………………………………………………………… D Elements ……………………………………………………………………………………………………….7-28 Single Point Constraints ………………………………………………………………………………………… Distributed Loads …… ………………………………………………………………………………………… Force ……………………………………………………………………………………………………………… Element Distortion …………………………………………………………………………………………………7-120 Composite Materials ……………………………………………………………………………………………… Case Study: Intercooler Structure Solid Geometry ……………………………………………………………………………………………………..8-9 The CHEXA Element ………………………………………………………………………………………………8-14 Post Processing Solid Element Results …………………………………………………………………………8-34 Solid Elements …………………………………………………………………………………………………… Case Study: Scuba Tank Model Simplification Methods ………………………………………… …………………………………………9-6 Importing Geometry ……………………………………………………………………………………………….9-11 Viewports ………………………………………………………………………………………………………… Mesh Density Control …………………………………………………………………………………………….9-64 Axisymmetric Elements …………………………………………………………………………………………..9-80
Copyright 2006 MSC.Software Corporation TABLE OF CONTENTS SectionPage 10.0Case Study: Car Design Groups ………………...…………………………… ………………………………………………………………10-6 Lists …………………………………………………………………………………………………………………10-27 Spring, Bush, and Mass Elements ……………………………………………………………………………… Rigid Elements ……………………………………………………………………………………………… Units Units in MSC.Nastran …………………………………………………………………………………………… Examples of Consistent Systems of Units ……………………………………………………………………… Case Study: Communications Tower Equations of Motion ……………………… ………………………………………………….………………… Mass Matrix Formulation …………………………………………………………………………………………12-10 Eigenvalue Extraction Methods ………………………………………………………………………………… Case Study: Submarine Pressure Hull - 3D Concept of Linear Buckling …………..…… …………………………………………………………………… Setting Up Linear Buckling Solution …………………………………………………………………………… Parasolid Modeling Parasolid Modeling Tools …………………… ………………………………………………………………….14-3
Copyright 2006 MSC.Software Corporation