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Is there any model about anchor damping in COMSOL?

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Hi everyone

I am a beginner in COMSOL and I want to calculte the anchor-loss-limited Q in MEMS resonator (square plate resonator which has four anchors at its four corners). I think the perfectly matched layers (PMLs) should be used to absorp the outgoing elastic energy. Could anyone share a model about anchor damping? Thanks.

James

4 Replies Last Post 27.03.2012, 06:26 GMT-4
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Hello James

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Posted: 1 decade ago 16.03.2012, 13:20 GMT-4
Hi James,

You can refer to the attached paper. In this paper, the material properties that you can enter for the Matched Layer is mentioned.:

Good luck,
Amir
Hi James, You can refer to the attached paper. In this paper, the material properties that you can enter for the Matched Layer is mentioned.: Good luck, Amir


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Posted: 1 decade ago 20.03.2012, 08:00 GMT-4

Hi James,

You can refer to the attached paper. In this paper, the material properties that you can enter for the Matched Layer is mentioned.:

Good luck,
Amir


Hi Amir

Thanks for your help. I have one question for this paper. Do you know how to calculate the attenuation constant alpha? The author of this paper sets it to 3 but gives no reason.

Regards,

James
[QUOTE] Hi James, You can refer to the attached paper. In this paper, the material properties that you can enter for the Matched Layer is mentioned.: Good luck, Amir [/QUOTE] Hi Amir Thanks for your help. I have one question for this paper. Do you know how to calculate the attenuation constant alpha? The author of this paper sets it to 3 but gives no reason. Regards, James

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Posted: 1 decade ago 26.03.2012, 17:22 GMT-4
James:

I think you have figure that out by yourself. It is geometry dependent and for high Q-factors you require a different a than 3. Play with mesh size and a and see when your result converges.

Cheers,
Hadi
James: I think you have figure that out by yourself. It is geometry dependent and for high Q-factors you require a different a than 3. Play with mesh size and a and see when your result converges. Cheers, Hadi

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Posted: 1 decade ago 27.03.2012, 06:26 GMT-4
Hello,

Can you guys tell me how to calculate Q-factor using Eigen frequency analysis? Basically I have cantilever beam, but I do not how to calculate Q-factor.

Thanks

Sankha
Hello, Can you guys tell me how to calculate Q-factor using Eigen frequency analysis? Basically I have cantilever beam, but I do not how to calculate Q-factor. Thanks Sankha

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