Extracting Mass Fractions from a Free-Free Modes analysis in FEMAP

[Guncici]

Hey All,

Sorry if this has been discussed before but I have a question about free free modes.

I am running a free free modes analysis and I need to extract the Effective Mass Fractions after the rigid body modes. However the rigid body modes take up 100% of the fraction and all subsequent modes have a mass fraction of roughly 0.

The question is: Is there a way for the mass fractions to only start counting after the rigid body modes?

I did try to set the "Range of Interest" from 1 Hz to 2000 Hz but it still took out the mass fractions from the rigid body modes.

Cheers,

Guncici

 

[FFB12]

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