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Factoring the Mass Matrix of a Super-Element

Pioneer
Pioneer

Hi

Is it possible to factor the mass matrix of an external super-element (i.e. stored on an op4 file) without reducing the model again?

 

If using super-elements on DMIG cards you can factor the M2GG card eg M2GG=1.25*MAAX, but how does one factor a super-element stored in an op4 file?

Thanks

Peter

5 REPLIES

Re: Factoring the Mass Matrix of a Super-Element

Siemens Phenom Siemens Phenom
Siemens Phenom

I do not know of any way to do that, unless you wanted to try some DMAP. I believe recreating the superelement would be easier than DMAP.

 

Regards,

Joe

Re: Factoring the Mass Matrix of a Super-Element

Pioneer
Pioneer

Thanks Joe

Unfortunately the super-element was delivered to me in op4 format, and I wanted to simply add a project mass margin.

Time to convert the op4 matrix to DMIG cards.....

Regards

Peter

Re: Factoring the Mass Matrix of a Super-Element

Genius
Genius

Maybe you could scale your accelerations instead.

Re: Factoring the Mass Matrix of a Super-Element

Pioneer
Pioneer

Unfortunately I need to apply a different system level mass factor to each subcomponent to account for their level of system maturity

Re: Factoring the Mass Matrix of a Super-Element

Genius
Genius

I think that you could scale the diagonal values of the mass matrix directly (i.e. dumb multiply) because the translational terms are just [kg] and the rotational terms are derived from M*r^2-like equations, in which the mass is a linear term. The off-diagonal terms are probably not so easy. They're also usually less important though.