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Vibrating horizontal plate.

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Good Evening everyone,

I have a really simple question, I'm sure someone knows the answer to my problem.
I'm trying to make a model of a plate, platform, anything you want to call it, that vibrates only horizontally, like a piezoelectric device. Can anyone give me some kind of explanation on how to do it?

Thank you very much.

9 Replies Last Post 2013年6月14日 GMT-4 13:48
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2013年2月28日 GMT-5 02:19
Hi
Here is an example with a horizontal acceleration at one end, you see you excite the poston compression mode
But this you should manage to do too no ?

model is4.3a I do not have any older ones up running

--
Good luck
Ivar
Hi Here is an example with a horizontal acceleration at one end, you see you excite the poston compression mode But this you should manage to do too no ? model is4.3a I do not have any older ones up running -- Good luck Ivar


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Posted: 1 decade ago 2013年2月28日 GMT-5 06:14
Dear Ivar,

My Comsol License is older than the one with which this example was made, so I cannot open it.
I really can't manage to do that. I've worked with Comsol before but not with the Structural Mechanics module.
In principle, what I want to do is really simple, just create a 2D geometry, a square, and then add some vibration to it, in only one direction and this is my problem.

Thank you very much for your help.
Dear Ivar, My Comsol License is older than the one with which this example was made, so I cannot open it. I really can't manage to do that. I've worked with Comsol before but not with the Structural Mechanics module. In principle, what I want to do is really simple, just create a 2D geometry, a square, and then add some vibration to it, in only one direction and this is my problem. Thank you very much for your help.

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2013年2月28日 GMT-5 08:20
Hi

that is what I did, made a rectangle, added an acceleration BC on one lateral side, and then used a harmonic sweep solver to see the response.

One easily see the compression or longitudinal frequency resonace at 1320 Hz for ma 1m x 0.1 m Al plate example in 2D

I did not use any other BC so the solution might integrate away due to roundoff errors, probably not in frequency domain solving, but in time solving, but then one need to use a sin() acceleration, or simply a sin() displacement

--
Good luck
Ivar
Hi that is what I did, made a rectangle, added an acceleration BC on one lateral side, and then used a harmonic sweep solver to see the response. One easily see the compression or longitudinal frequency resonace at 1320 Hz for ma 1m x 0.1 m Al plate example in 2D I did not use any other BC so the solution might integrate away due to roundoff errors, probably not in frequency domain solving, but in time solving, but then one need to use a sin() acceleration, or simply a sin() displacement -- Good luck Ivar

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Posted: 1 decade ago 2013年3月2日 GMT-5 09:21
Thank you very much Ivar. :)

I'll try that.
Thank you very much Ivar. :) I'll try that.

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Posted: 1 decade ago 2013年3月4日 GMT-5 11:22
Dear Ivar,

I'm trying to develop the model as you indicated.
Can you please tell me which module you used? I'm currently using Pressure Acoustics, Frequency Domain and adding a BC (acceleration). Is this the right way?

Thank you for your help.
Dear Ivar, I'm trying to develop the model as you indicated. Can you please tell me which module you used? I'm currently using Pressure Acoustics, Frequency Domain and adding a BC (acceleration). Is this the right way? Thank you for your help.

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2013年3月4日 GMT-5 14:39
Hi

I do not have the acoustic module, so my case was simply in "solid", I do not know which BC exist in "ACO"

--
Good luck
Ivar
Hi I do not have the acoustic module, so my case was simply in "solid", I do not know which BC exist in "ACO" -- Good luck Ivar

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Posted: 1 decade ago 2013年3月5日 GMT-5 08:26
Thank you very much for your help Ivar :)
Thank you very much for your help Ivar :)

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Posted: 1 decade ago 2013年3月12日 GMT-4 05:56

Hello!

With the a simple plate in Acoustics module, you should solve an eigenvalue problem first to see at what frequency your plate will vibrate with most naturally. You can of course excite at what frequency you wish but the eigen frequencies are very important to know nevertheless. Note that while using acoustics module, you may have to enter the speed of sound in the material properties if you use solid materials.

After finding the natural frequencies of vibration you can just do study in frequency domain with the acceleration BC. I entered an "inward acceleration" with an amplitude 0.5*sin(2*pi*f0).
--
Hope this helps
--
/RVN
Hello! With the a simple plate in Acoustics module, you should solve an eigenvalue problem first to see at what frequency your plate will vibrate with most naturally. You can of course excite at what frequency you wish but the eigen frequencies are very important to know nevertheless. Note that while using acoustics module, you may have to enter the speed of sound in the material properties if you use solid materials. After finding the natural frequencies of vibration you can just do study in frequency domain with the acceleration BC. I entered an "inward acceleration" with an amplitude 0.5*sin(2*pi*f0). -- Hope this helps -- /RVN

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Posted: 1 decade ago 2013年6月14日 GMT-4 13:48
RVN,
I am doing something similar. (a flat panel with 4 exciters) I just started using this program. What tab is BC acceleration located, and what is the f0 value? Do you have any advice for simulating the vibration created by the exciters?
RVN, I am doing something similar. (a flat panel with 4 exciters) I just started using this program. What tab is BC acceleration located, and what is the f0 value? Do you have any advice for simulating the vibration created by the exciters?

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