Main Help → All Commands → Gravity
The Gravity
command adds a gravitational force field to an MPM simulation:
Gravity <(accx)>,<(accy)>,<(accxz)>
where (accx)
, (accy)
, and (accz)
are the accelerations due to gravity (in acceleration units) in the x, y, and z directions, respectively ((accx)
(accy)
are for R and Z directions in axisymmetric calculations). All three parameters are optional. If any are omitted, the gravitational force field is set to Earth's gravity with down being in the negative y direction (i.e., the default values are (0,-9806.65 mm/sec2,0) in Legacy mode or (0,-9.80665 acceleration units,0) in consistent units mode).
Any of the parameters can alternatively be a user-defined function of x, y, and z (in length units) and t (in alt time units) to give position and/or time dependent body forces. The functions should evaluate to acceleration in acceleration units.
Gravity
command is only allowed for MPM analyses.