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*DAMPING

Keyword type: model definition

This card is used to define Rayleigh damping for implicit dynamic calculations (*DYNAMIC). There are two required parameters: ALPHA and BETA.

Rayleigh damping is applied in a global way, i.e. the damping matrix $ \left [ C \right ]$ is taken to be a linear combination of the stiffness matrix $ \left [ K \right ]$ and the mass matrix $ \left [ M \right ]$:

$\displaystyle \left [ C \right ] = \alpha \left [ M \right ] + \beta \left [ K \right ].$ (334)

Right now, only one *DAMPING card can be used in the input deck. It applies to the whole model.


First line:

Example:

*DAMPING,ALPHA=5000.,BETA=2.e-3

indicates that a damping matrix is created by multiplying the mass matrix with $ 5000.$ and adding it to the stiffness matrix multiplied by $ 2 \cdot 10^{-4}$


Example files: beamimpdy1, beamimpdy2.



guido dhondt 2016-03-08