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Domain Overlapping after simulation

Please refer to the attached figure, where I have a part of the object I am simulating shown. After simulation the two legs overlaps each other. how does it affect the results? How to remove this overlapping? This is a 2D plane stress model with eigenfrequency analysis.


3 Replies Last Post 2013年10月15日 GMT-0400上午2:18
Henrik Sönnerlind COMSOL Employee
Posted: 4 years ago 2013年10月14日 GMT-0400上午2:14
Dear Ruzbeh,

Since it is an eigenfrequency analysis, the size of the deformations is arbitrary. So without running a forced response analysis with actual loads in for example frequency domain, there is no way to know whether these parts would actually get in to contact or not. But if they do, there is nothing such as an eigenfrequency of the structure.

Regards,
Henrik
Dear Ruzbeh, Since it is an eigenfrequency analysis, the size of the deformations is arbitrary. So without running a forced response analysis with actual loads in for example frequency domain, there is no way to know whether these parts would actually get in to contact or not. But if they do, there is nothing such as an eigenfrequency of the structure. Regards, Henrik

Posted: 4 years ago 2013年10月14日 GMT-0400上午7:06
Dear Henrik

Thank you for the reply. Basically this is a resonator. The frequency I got from my simulation has good agreement with experimental result. Since the deformations are arbitrary, I hope the contact between parts does not matter really. Does the problem become Non-linear when considering contact between parts?

I know the driving frequency of the resonator, is it possible to have a freqeuncy response analysis using this?

Thanks.
Dear Henrik Thank you for the reply. Basically this is a resonator. The frequency I got from my simulation has good agreement with experimental result. Since the deformations are arbitrary, I hope the contact between parts does not matter really. Does the problem become Non-linear when considering contact between parts? I know the driving frequency of the resonator, is it possible to have a freqeuncy response analysis using this? Thanks.

Henrik Sönnerlind COMSOL Employee
Posted: 4 years ago 2013年10月15日 GMT-0400上午2:18
Hi Ruzbeh,

If the parts would actually come in contact at resonance, the problem becomes severely nonlinear and can only be simulated in time domain, and to a great effort. The solutions are no longer harmonic, and a lot of high frequencies will be generated by the impact.

If you know the driving frequency and load amplitude, then you should do a frequency response simulation to check that there is no contact. Note however that if you are close to resonance, the computed amplitudes will be strongly dependent on the damping values that you select.

Regards,
Henrik
Hi Ruzbeh, If the parts would actually come in contact at resonance, the problem becomes severely nonlinear and can only be simulated in time domain, and to a great effort. The solutions are no longer harmonic, and a lot of high frequencies will be generated by the impact. If you know the driving frequency and load amplitude, then you should do a frequency response simulation to check that there is no contact. Note however that if you are close to resonance, the computed amplitudes will be strongly dependent on the damping values that you select. Regards, Henrik

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