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modal analysis
- Thread starter marouaha
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Hi,
the normal modes analysis available in Nastran does not take into account the damping, in fact the equation of motion is
[M]{a} + [K]{u} = 0
which is the equation of motion for undamped free vibration (where: [M] is the mass matrix, [K] the stiffness matrix, {a} the acceleration and {u} the displacement vectors).
To take into account modal damping you need to run a frequency analysis with a force applied to the structure.
Regards
the normal modes analysis available in Nastran does not take into account the damping, in fact the equation of motion is
[M]{a} + [K]{u} = 0
which is the equation of motion for undamped free vibration (where: [M] is the mass matrix, [K] the stiffness matrix, {a} the acceleration and {u} the displacement vectors).
To take into account modal damping you need to run a frequency analysis with a force applied to the structure.
Regards
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