The rotational velocity of the structure is specified via the OMEGA or CMOMEGA commands. For the OMEGA command, define the rotational velocity vector along one of the global coordinate system axes. The gyroscopic effect is set via the CORIOLIS command.
omega,1000. coriolis, on,,, on ! last field specifies stationary reference frame
Note: In rotordynamics, the effect of the rotating inertias is calculated in the
stationary reference frame (the scope of this guide). The
RefFrame argument of the CORIOLIS
command must be set accordingly.
Unlike OMEGA, CMOMEGA lets you define a rotational velocity vector independent of the global X, Y or Z axes. For example, you may define the direction of the rotational velocity vector using two points and the rotational velocity as a scalar, as follows:
! Define rotational velocity for COMPONENT1: ! spin is 1000 rd/s ! direction is parallel to Z axis and passing through point (0.1,0,0) cmomega, COMPONENT1, 1000.,,, 0.1, 0, 0, 0.1, 0,1
The load interpolation setting (KBC) applies to the rotational velocity. It can be stepped, linearly interpolated, or quadratically interpolated over a load step.