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Effective mass and Inertia

Effective mass and Inertia

Effective mass and Inertia

(OP)
Hi,

I have a simple question:

After I had realised a frequency analysis to calculate natural frequency of my model, I calculate effective mass and inertia. I just want to know what is the physical sense of these values. Moreover, if a mode has a very low effective mass and inertia, is it mean that I can don't consider this mode because it is not significant?

Thanks

Jérome

 

RE: Effective mass and Inertia

Tricky. The local modal mass (a/F) is quite a handy thing to know. I'm never very sure about what the FE guys call a modal mass, they seem to think it means something like what you are talking about. SO it depends how you work it out. I know at least 4 ways.

 

Cheers

Greg Locock


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RE: Effective mass and Inertia

(OP)
In fact, I calculate natural frequencies of a pump to know if theses frequencies are near to the rotation velocity.

And I believe that : if a mode is near to the rotation frequency but it has a effectiv mass very low, it is not a problem because in reality, this mode will not be important.

Is it true?

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