Flange Holes

You can choose to mesh or ignore holes that include a flange raised or sunken from the surrounding surface.

See Also
Creating and Editing Surface Meshes
Feature Parameters

Flange holes might be critical attachment points that are integral to a simulation of the part's structural behavior. Conversely, they might be reference points for fixtures that have no importance in the useful life of the part. By creating local feature specifications (rules), you can identify these model features and specify how to mesh them. You can also ignore them so that they are meshed like a simple hole and the projected flange is flattened in the mesh.

A flange hole has two defining characteristics: hole diameter and height above the surrounding surface. The hole diameter is measured at the top of the flange, and the height accounts for the deformation area at the base of the flange as well as the upper portion (the entire area highlighted blue in the image).

Recognizing flange holes as a special type of feature generally results in a better mesh because they are usually relatively small compared to the model. This means that the general mesh parameters used for the surrounding surface could yield a poor representation for the sudden change of shape around these holes.

When creating rules for flange holes, you can specify a minimum and maximum for the diameter and for the height. You can create rules to mesh flange holes that fit one set of parameters and to ignore flange holes that fit a different set of parameters. If you accidentally create conflicting rules, the conflict is highlighted and you can adjust the rules or delete a rule to resolve it.

Note: If a potential problem is detected with values you entered, a confirmation dialog box indicates the possibility of a poor mesh (oversized or undersized elements) and allows you to return to the editor and redefine parameters or to continue with the current settings.