ExtrapolateRigid Command
The ExtrapolateRigid command activates a mode where rigid particles for setting boundary conditions extrapolate to the nodes before setting boundary conditions:
Use ExtrapolateRigid
In scripted files, the command is
ExtrapolateRigid <(option)>
where (option) is "yes" to activate the mode or anything else to not activate the mode. If this optional command is omitted, it is assumed to be "yes". In XML input files, the mode is activated with the empty command, which must be within the <MPMHeader> element:
< ExtrapolateRigid/>
When this option is activated, all rigid material particles that set boundary conditions for velocity, temperature, or concentration, will extrapolate to the grid first and then set boundary conditions using those extrapolated values instead of the rigid particle velocity, temperature, or concentration. This option only provides potential benefit when the rigid particle values vary with position, such as loading in shear. When all rigid particles have the same velocity, it is better to not use this option.
Notes
- When this mode is activated, all rigid material particles use the extrapolation approach and the boundary conditions they create are assigned ID = -40, which can be used when archiving reaction forces. In this mode it is not possible to separate reaction forces on different types of rigid material.
- When this mode is activated, the mirror property for rigid materials is ignored