Keyword type: step
This card is used within a step in which the *MODAL DYNAMIC or *STEADY STATE
DYNAMICS procedure has been selected. It allows for Rayleigh damping in a
global way, i.e. the damping matrix
is taken to be a linear combination of the
stiffness matrix
and the mass matrix
:
![]() |
(121) |
The coefficients apply to all modes. The corresponding friction coefficient
for mode j amounts to:
![]() |
(122) |
Consequently, damps the low frequencies,
damps the high
frequencies.
The only parameter RAYLEIGH is required.
First line:
Example: *MODAL DAMPING,RAYLEIGH ,,0.,2.e-4
indicates that the damping matrix is obtained by multiplying the stiffness matrix with
Example files: beamdy3, beamdy4, beamdy5, beamdy6.