• Your account on mahler.udel.edu and initial setup

 
• Changing your default project number

 
• Disk usage and quota

 
• Useful Unix Commands

 
• Introduction to ANSYS

 
• Solve the steel plate problem with ANSYS

Your account on mahler and initial setup for FIDAP:

All of you should have accounts on mahler (mahler.udel.edu).  The username and password are the same as on Copland (copland.udel.edu).
 

• telnet mahler.udel.edu

 
• login with your username and passward

 
• create a .cshrc file with the following lines

setenv     PATH    /opt/lib/fidap8.6/Fluent.Inc/bin:$PATH
 

• cd /tmp

 
• mkdir Alex (or your directory name)

 
• cd Alex (or your directory name)

 
• fidap -id test -gui -new

 
• exit fidap

Changing your default project number

When you use a computer, you are in effect renting time on it, the cost of which is charged to a project number. At the University of Delaware, you may be authorized to use several projects. For example, most students are authorized to use an email account which has project number 4000. Once officially registered you will be authorized to use your class project for doing computer work for MEEG 481/681. The project number for this course is 2172.

Whenever you log on, the computer time that you use is automatically charged to a project called your default project. Use the Unix command chdgrp to find out your default project number and all the project numbers that you are authorized to use.

Whenever you want to do MEEG481/681 work, type the command newgrp 2172. This will switch you to project 2172 until you type exit. You must do this every time you want to do MEEG 481/681 work.

Alternatively, type the command chdgrp 2172. This will change the default project so that you will be working on project 2172 automatically each time you log on in the future. Use the command newgrp when you want to work on non- MEEG481/681 work. Note: it may take up to 24 hours for your old project to be replaced by the new one.

Disk Usage and Quota

You may need some extra disk space to save your MEEG481/681 computer work. There is a special directory with a disk quota increased to 100 mb for your use. The directory is under /home/base/usrb/meeg681.

Even with this privilege, I would like to ask you to always run ANSYS/FIDAP under /tmp directory. When you finish an ANSYS/FIDAP session, make sure that you only save the necessary files which will allow you to re-create the session (such as the log file, etc.). You do this by the Unix command cp. For example,
cp /tmp/lwang/plate.log /home/base/usrb/meeg681/lwang/plate.log

Please do not save the database files generated by ANSYS/FIDAP under usrb/meeg681/. Note that this special disk quota will revert back to the current default limits after the semester is over. It is your responsibility to delete the files at the end of the course so that they remain under their current disk quota.

You can display your quota usuage by the Unix command quota.

Useful Unix commands

The folowing table includes brief descriptions of some of the Unix commands you will use most often in doing your work for this course. You should become familiar with these commands as quickly as possible.

useful unix commands

Introduction to ANSYS

What is ANSYS?

ANSYS is a commercial software package developed by ANSYS, Inc.

Contains simulation programs that allow multiphysics analysis including

• Deformation and stress analysis of solids/structures - linear/nonlinear, statics/transient
• Thermal (Conduction, convection, radiation)
• Computational Fluid Dynamics (CFD)
• Electromagnetics
• .....

• Set up the model or Preprocessing
• Build the geometry
• Select a mesh type and build the mesh
• Set up the material properties
• Input boundary conditions and Loads
• ....
• Solve the model problem
• Analyze the results (Postprocessing)

Solve the steel plate problem:

One-D model:

  The problem can be solved by 1D link elements 
     or by 2D solid elements (set Poisson ratio = 0).

Two-D model:
  
  The problem can be solved by 2D solid elements 
        with realistic Poisson ratio.

Steps for the one-D link-element model: (Handout)
 

Steps for the two-D solid-element model: (Handout)

Comments:  The 1D links overestimate the solution, while 2D plate elements underpredict the solution at x=12.
 
 

How to print a hardcopy of the graphics window?

PlotCtrls -  Redirect plots - TO PSCR File - Replot