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Region Command

This command can add material points to an MPM calculation or assign material types to elements in an FEA calculation.

MPM Calculations

Material points are added to an MPM analysis by using a series of Region commands and BMPRegion commands. The Region command defines material type, initial velocities, 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 to be filled with material points. For 2D MPM, the structure is:

Region (id),(velx),(vely),(thick),<(prop),(value)>...
  (one optional Transform command)
  (optional Rotate commands)
  (optional AngularMom0 command)
  (any number of 2D shape commands)
EndRegion

For 3D MPM, the structure is:

Region (id),(velx),(vely),(velz),<(prop),(value)>
  (one optional Transform command)
  (optional Rotate commands)
  (optional AngularMom0 command)
  (any number of 3D shape commands)
EndRegion

where

When using anisotropic materials, Rotate commands within a Region block can apply transformations to the material axes to define initial orientation of selected material points in the body.

If you set the "res" in a region that differs from the default setting, the code will no longer check to make sure particles are not overlapping. The user is therefore responsible for defining non-overlapping regions. Note also that this setting can use any valid number per element side and is not limited to the values allowed when choosing the default setting.

If you want void spaces within a region with no material points, you can use Hole Commands before the Region command or can use nested shapes with the Cut command.

FEA Calculations

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. Once the mesh is ready, 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 shape command that define the geometry whose elements will use that material. The structure for 2D FEA is:

Region (id),(thick),<(angle)>
  (any number of 2D shape commands)
EndRegion

where

If you want void spaces within a region to remove elements, you can use Hole Commands before the Region command or can use nested shapes with the Cut command.