Finite Element Analysis Using ANSYS

INTRODUCTION

ANSYS is the original (and commonly used) name for ANSYS Mechanical or ANSYS Multiphysics, general-purpose finite element analysis software. ANSYS, Inc actually develops a complete range of CAE products, but is perhaps best known for ANSYS Mechanical & ANSYS Multiphysics. The referred to as ANSYS Academic Research, ANSYS Academic Teaching Advanced, Introductory etc. All of these products are general purpose finite element self contained analysis tools incorporating preprocessing (geometry creation, meshing), solver and post processing modules in a unified graphical user interface (GUI). For the remainder of this appendix, when we state ‘‘ANSYS’’, we mean the FEA capability of either the commercial or academic ANSYS Inc. products discussed above. Further we are limiting our discussion to the traditional (or ‘‘classic’’) user interface of ANSYS, not the ANSYS Workbench environment.

One of the advantages of ‘‘ANSYS’’ is the user-programmable capability. The ANSYS Command Language contains several thousand commands relating to creating geometry, mesh, boundary conditions, solver settings & many other features. A subset of these commands are termed ANSYS Parametric Design Language (APDL), and focus on managing parameters, macros, if-then-else branching, do-loops, and scalar, vector and matrix operations. For example, if multiple analyses are required with different values of parameters, do-loops can be used to change parameters, or the Optimization module (/OPT) can be used to automatically manage parameters & populate a response surface.

One of the advantages of ‘‘ANSYS’’ is the user-programmable capability. The ANSYS Command Language contains several thousand commands relating to creating geometry, mesh, boundary conditions, solver settings & many other features. A subset of these commands are termed ANSYS Parametric Design Language (APDL), and focus on managing parameters, macros, if-then-else branching, do-loops, and scalar, vector and matrix operations. For example, if multiple analyses are required with different values of parameters, do-loops can be used to change parameters, or the Optimization module (/OPT) can be used to automatically manage parameters & populate a response surface

There are two different modes of inputting commands in ANSYS: graphic mode and text mode. In the graphic mode, the user can pick commands and type in required data values. Thus, there is no need to memorize all commands. This mode is beneficial in a sense that the user can see the result of each command in the graphic window. In the text mode, the user type in commands and data in the command area. In this case, the user should remember what command should be used to perform a particular action. However, the text mode has its own advantages. For example, during the design process, the user 363 may want to perform the analysis multiple times with different values of parameters. In such a case, the user can prepare a text file of all commands and then input the file as an input command file. In fact, all actions in the graphic mode are stored as commands in a text file, jobname.log. Thus, it would be a good practice to prepare the initial model using the graphic mode, and then, modify the input file for the further modification.