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Extracting Eigenvalues and Eigenvector using Eigenfrequency study

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Hello,

I was successfully able to extract the first N (~ 50) eigenvalues, using Eigenfrequency study and Solid Mechanics physics setup. I use the export option to write out the frequencies and eigenvalues (lambda).
However, now I also need the corresponding Eigenvectors. I am not able to do the same, since the exporter does not show Eigenvectors in the export list.

Pls let me know how I can export the first N eigenvalue and eigenvectors pairs. Is there is a simpler way to do this using Matlab LiveLink?

Thanks,
Gaurav

2 Replies Last Post 3 dic 2014, 08:31 GMT-5

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Posted: 10 years ago 2 dic 2014, 22:26 GMT-5
Could someone pls answer. I have seen posts (e.g. www.comsol.com/community/forums/general/thread/31634/) where people talk about having Eigenvectors data access, but am not sure how they actually extract it from COMSOL.

Thanks,
Gaurav
Could someone pls answer. I have seen posts (e.g. http://www.comsol.com/community/forums/general/thread/31634/) where people talk about having Eigenvectors data access, but am not sure how they actually extract it from COMSOL. Thanks, Gaurav

Henrik Sönnerlind COMSOL Employee

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Posted: 10 years ago 3 dic 2014, 08:31 GMT-5
Hi,

You should be able to select displacements in the Expressions section of Results->Export->Data. If you do not find them in the list, you can always write u, v and w explicitly in the list of expressions.

Which physics interface (element type) are you using? If it is 'subdimensional' (like a shell which lives on surfaces in 3D) you may have to do a manual selection for 'Geometry Level' in Results->Export->Data.

Regards,
Henrik
Hi, You should be able to select displacements in the Expressions section of Results->Export->Data. If you do not find them in the list, you can always write u, v and w explicitly in the list of expressions. Which physics interface (element type) are you using? If it is 'subdimensional' (like a shell which lives on surfaces in 3D) you may have to do a manual selection for 'Geometry Level' in Results->Export->Data. Regards, Henrik

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