29-03-2012, 04:22 PM
Finite Element Method using Pro/ENGINEER and ANSYS
9. Finite Element Method using ProENGINEER and ANSYS.pdf (Size: 343.41 KB / Downloads: 115)
Make the part
Use Pro/E to make the part. Things to note are:
be aware of your model units
note the orientation of the model (default coordinate system in ANSYS will be the same as in Pro/E)
IMPORTANT: remove all unnecessary and/or cosmetic features like rounds, chamfers, holes, etc., by suppressing them in
Pro/E. Too much small geometry will cause the mesh generator to create a very fine mesh with many elements which will
greatly increase your solver time. Of course, if the feature is critical to your design, you will want to leave it. You must
compromise between accuracy and available CPU resources.
Create the FEM model
In the pull-down menu at the top of the Pro/E window, select
Applications > Mechanica
An information window opens up to remind you about the units you are using. Press Continue
In the MECHANICA menu at the right, check the box beside FEM Mode and select the command Structure.
A new toolbar appears on the right of the screen that contains icons for creating all the common modeling entities (constraints, loads,
idealizations). All these commands are also available using the command windows that will open on the right side of the screen or in
dialog windows that will open when appropriate.
Notice that a small green coordinate system WCS has appeared. This is how you will specify the directions of constraints and forces.
Other coordinate systems (eg cylindrical) can be created as required and used for the same purpose.
The MEC STRUCT menu appears on the right. Basically, to define the model we proceed down this menu in a top-down manner.
Model is already selected for you which opens the STRC MODEL menu. This is where we specify modeling information. We proceed
in a top-down manner. The Features command allows you to create additional simulation features like datum points, curves, surface
regions, and so on. Idealizations lets you create special modeling entities like shells and beams. The Current CSYS command lets you
create or select an alternate coordinate system for specifying directions of constraints and loads.
Defining Constraints
For our simple model, all we need are constraints, loads, and a specified material. Select
Constraints > New
We can specify constraints on four entity types (basically points, edges, and surfaces). Constraints are organized into constraint sets.
Each constraint set has a unique name (default of the first one is ConstraintSet1) and can contain any number of individual constraints
of different types. Each individual constraint also has a unique name (default of the first one is Constraint1). In the final computed
model, only one set can be included, but this can contain numerous individual constraints.