How to retrieve ASET mode shapes (phi matrix) in HDF5 output?

Using the NASTRAN HDF5 = 0 command with DISP(PLOT)=ALL it appears that the mode shapes are for the G SET. In HDF Compass I see /NASTRAN/RESULT/NODAL/EIGENVECTOR has the same grid ID's from a USETPRT of the G SET. The A SET has 529 dofs while the G SET has 924.

0 Sanjay Patel over 5 years ago

Hi Matthew,

Nastran will always give you output for all the grids. Most simple way to control it is by having ASET grids specified via a set in the output request. In the example below 100, thru,110 are ASET grids. You will get the output for all 6 dofs of the ASET grids.

DISP=10

SET 10= 100,thru,110

Thanks,

Sanjay.
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0 matthew.goit over 5 years ago

Thanks for the prompt reply. The goal is to replace the MSC DB Toolbox with H5 output. Currently I can use the toolbox with version 2013 and prior to get the ASET directly from the DBALL/MASTER, without knowing what it is beforehand. I can create the SET you mention, but what about the cases where I don't define it ahead of time? Can I ask NASTRAN to create the SET for me? In my test case I don't manually create the ASET, NASTRAN does that internally. When I do specify the ASET your solution works great. An option like DISP(...)=ASET would be nice.
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0 Ken Walker over 5 years ago

Matthew, this isn't directly supported in Nastran. However, you can use DMAP to extract and write the ASET to HDF5 with the CRDB_MTX function. The data will be in the job.mtx.h5 file, in group: /NASTRAN/RESULT/MATRIX/GENERAL (3 datasets, same indexing method as other matrix output).
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