SOLVERS Home: Mode Participation

Description

The Mode Participation option applies to the Natural Frequency solver.

Calculate Mode Participation

If set, calculates the mode participation factors for translational excitation, as well as the mode participation mass ratios for both translational and rotational excitations. One set of factors and ratios is calculated for each mode for each of the participation types. In addition, if the material damping ratio is specified in the property set, the effective modal damping ratio for each mode is also calculated. All of these quantities are reported in the solver log file.

Translation Axis

Translation participation direction vector specified in global XYZ axes.

The magnitude of the vector is not important as the vector is used in its normalised form. If all components of the vector are zero, the translational excitation direction is applied in all three of the global XYZ directions. If the vector contains non-zero components, the translational excitation is applied only in the direction of the vector.

Rotation Origin

A point defined in global XYZ coordinates that positions the Rotation Axis for rotational mode participation mass ratio calculations.

Rotation Axis

An axis defined in the global XYZ directions, passing through the Rotation Origin about which the rotational mode participation mass ratios are calculated.

The magnitude of the vector is not important as the vector is used in its normalised form. If all components of the vector are zero, rotational mode participation mass ratios are calculated about all three global XYZ axes. If the vector contains non-zero components, rotational mode participation mass ratios are calculated only about the specified axis.