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Transmission loss in simple model

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Hi,

I'd like to analyze the frequency dependency of the transmission loss (TL) of a simple structural/acoustic model, which is depicted here: www.alfwarnock.info/sound/images/tlsuite.gif

Some problems I stumbled upon:
1) I'm not sure how to apply the acoustic load. I want to model a pressure wave that excites the entire frequency spectrum (so, swept sine or white noise).
2) The pressure in the right reception room does not change, even though the middle panel deforms.

If anyone can help to get me started, that would be great!

3 Replies Last Post Sep 21, 2016, 10:33 p.m. EDT

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Posted: 1 decade ago Jul 1, 2012, 12:28 a.m. EDT
Hi Frits

You'll need to run the acsh (acoustic-shell interaction frequency domain) module. You'll need only the air in both room modeled with rigid reflective walls, and the plate as a shell model.
1) There is no "white noise" option - use stepped sine by specifying the start, end and step size frequencies.
2) Use one or more Sound Power Point Sources in the left room or make the left wall of the left room to provide a "plane wave radiation" (add this function from the list) and add an "incident pressure field" with a specified amplitude (option under the plane wave radiation). The second option will give you a normal incidence TL while the first option a random incidence TL.

Good luck!
Hi Frits You'll need to run the acsh (acoustic-shell interaction frequency domain) module. You'll need only the air in both room modeled with rigid reflective walls, and the plate as a shell model. 1) There is no "white noise" option - use stepped sine by specifying the start, end and step size frequencies. 2) Use one or more Sound Power Point Sources in the left room or make the left wall of the left room to provide a "plane wave radiation" (add this function from the list) and add an "incident pressure field" with a specified amplitude (option under the plane wave radiation). The second option will give you a normal incidence TL while the first option a random incidence TL. Good luck!

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Posted: 10 years ago Aug 14, 2014, 3:56 a.m. EDT
But what model of material should be used and what should be the equation in variables list?
But what model of material should be used and what should be the equation in variables list?

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Posted: 8 years ago Sep 21, 2016, 10:33 p.m. EDT
Hi KarelR,

I managed to perform the analysis based on your suggestions. It matches relatively well with experimental results. Thank you for the tips.
Hi KarelR, I managed to perform the analysis based on your suggestions. It matches relatively well with experimental results. Thank you for the tips.

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