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Effective mass of the frequency analysis shows more than the model mass

Effective mass of the frequency analysis shows more than the model mass

Effective mass of the frequency analysis shows more than the model mass

(OP)
Hi,
I ran a frequency analysis in Abaqus to find the first natural frequency and frequency related 95% model mass. The obtained participation factors are very much low and also effective mass (e.g - 6.74E9) for the rotation components are larger than the total mass of the model (4.27E7). Can anyone explain this to me, please? the .dat file is attached here.
Thank you.

RE: Effective mass of the frequency analysis shows more than the model mass

I think the rotational components can be ignored. They are highly dependent on the location of the part and have no real meaning.

RE: Effective mass of the frequency analysis shows more than the model mass

(OP)
Hi, Thanks for your reply. I 'll ignore that part. But I have a problem with obtaining frequency related to 95% model mass.
I extracted 30 modes and participation factors are added together, the values are very low (e.g. 1.5, 2.3 and 2.0 for three components). Should I want to extract more modes (until I get the summation of 95) to find model mass related with 95% model mass? please find the attachment of the participation factors.

Thank You

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