FEA Region and Hole Commands

One way to create a complicated FEA mesh, especially for composite materials with complex structures of subelements, is to define them with shape commands rather the Area commands. The basic mesh creation steps when using shapes is described in the BMPRegion command help. Once the mesh is ready, elements are assigned to materials by using a series of Region, Hole, and BMPRegion commands. The Region command defines material type, thickness, and angle (needed for some Material types). Between the Region command and the subsequent EndRegion command, there can be any number of geometric commands that define the geometry whose element will use that material. The structure for 2D FEA is:

Region #1,#2,<#3>

 Rect #1,#2,#3,#4
   .
 Oval #1,#2,#3,#4
   .
 PolyPt #1,#2
 PolyPt #1,#2
 PolyPt #1,#2
 PolyPt #1,#2
 PolyPt
   .

EndRegion where

1. 1 is the material ID for a previously defined material.
2. 2 is the thickness of the region in mm.
3. 3 is an optional angle for the material which is only relevant for anisotropic materials. It can be entered as a number or as a user-defined function of the coordinates for the element centroid. The units are degrees.