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GridThickness Command

The GridThickness command sets the thickness for planar 2D MPM grids:

GridThickness (thick)

where (thick) is the grid thickness in length units.

Notes

  1. In planar calculations, the thickness is required when doing multimaterial contact that includes the optional volume check or when using traction, concentration flux or heat flux boundary conditions. If omitted, the thickness will be assumed to be 1 length unit and if that is not correct, the volume screening or boundary conditions will be wrong.
  2. The GridThickness is optional in single-material mode because thickness can be set when defining material point regions and when defining cracks. If used, however, all material points and cracks will default to this grid thickness. You can enter different values, although it is not recommended (and may change the physics in multimaterial simulations). A warning is printed in the output if a crack thickness does not match the grid thickness. Currently no warning is given if material points have a different thickness.
  3. The thickness must be set before using GridRect to set the size of the background grid.
  4. The GridThickness command is only allowed for MPM analyses.