# PARAM, WRH

Bulk Data Entry Used to include or exclude rotor material hybrid damping in rotor dynamics analysis.

Parameter Values Description
WRH <Real>

Default = 0.0

PARAM, WRH, <Real>

For Complex Eigenvalue or Transient Analysis:

If any Real value other than 0.0 (default) is specified, then it is included in the rotor dynamics equation as the equivalent "average" excitation frequency. This allows for the inclusion of the material hybrid damping terms included in the analysis.

For Frequency Response Rotor Dynamics Analysis:

When PARAM, GYROAVG is set to -1 (in order to bypass frequency dependent looping), only if any Real value other than 0.0 (default) is specified for WRH, then it is included in the rotor dynamics equation via the material hybrid damping term as the equivalent “average” excitation frequency. When PARAM, GYROAVG is not -1, this parameter is irrelevant.