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Reduction with Nastran Modalanalysis

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ultu

New member
Jun 27, 2012
5
Hello Nastran friends,

i want to do a modal analysis with a simple static reduction (guyan).
Here is an example:
Link

In this example they say, if ASET1 command is added to the bdf file, Nastran would perform a static reduction.
I've done a simple file with ASET1.

Link

The results in the .f06 file are not what i expected to be.
Guyan uses fixed nodes, so the first six eigenvalues should not be zero. Am i wrong?
There is no line, which says, if Nastran performed Modal Analysis with Static Reduction or without the Reduction.
And if i recover the xdb file with Patran, the results are similiar to modal analyses without the reduction.

Thanks,

Ultu

 
 http://files.engineering.com/getfile.aspx?folder=9edd9ec4-b427-49d2-ad7d-81d342c9bd77&file=full.bdf
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