Global Damping

The Global Damping PropertyManager sets the options for constructing the global damping matrix.

• Modal damping: You directly define a modal damping ratio for each mode.

Compute from material damping. When this flag is checked, the modal damping ratios are calculated based on the material damping ratio MDAMP.

Material damping ratio MDAMP is defined in the Properties tab of the Material dialog box.

Damping Ratios: You specify a critical damping ratio for each mode.

• Rayleigh damping: The global damping matrix is constructed as a proportional combination of the mass and stiffness matrices, for example:

C = a[M] + b[K]: where C is the damping matrix, M is the mass matrix, and K is the stiffness matrix.

Parameters

• Alpha Coefficient: Sets the mass-proportional coefficient a.

• Beta Coefficient: Sets the stiffness-proportional coefficient b.

You can also define concentrated dampers between two locations (for modal time history analysis only).

Related Topics

Damping effects

Rayleigh Damping