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Acoustic wall

Jaime Guilherme Leal Alves

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Sirs,

I need some help. I'm tring to do a basic simulation: I need to calculate how much energy pass through a simple concrete wall.

I did the following geometry: a box filled with air and in the middle a concrete wall. I have selected the frequency domain study on the acoustic-solid interaction module. I inserted the pressure on some edge and a rigid wall on the other air wall and on study settings, I put the frequency Range (0,100, 1000). I made the mesh and when I try to evaluate values ​​I'm with the following error (image attached):

Division by zero. - Function: / Failed to evaluate variable. - Variable: comp1.acpr.delta - Defined as: 1/(comp1.acpr.omega^2) Failed to evaluate expression. - Expression: dvol_spatial((1/comp1.acpr.rho_c)(comp1.acpr.delta(-comp1.acpr.gradpz))) Failed to evaluate Jacobian of expression. - Expression: ((-comp1.acpr.gradpxcomp1.acpr.gradtestpx-comp1.acpr.gradpycomp1.acpr.gradtestpy-comp1.acpr.gradpzcomp1.acpr.gradtestpz-comp1.acpr.p_ttest(comp1.p)comp1.acpr.ik^2)comp1.acpr.delta/comp1.acpr.rho_c)(dvol_spatial

What I must to change?

Thanks!



3 Replies Last Post 2020年3月28日 GMT-4 08:16
Edgar J. Kaiser Certified Consultant

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Posted: 5 years ago 2020年3月25日 GMT-4 03:23

My guess is that the zero frequency you start with is not valid in frequency domain.

Cheers Edgar

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
My guess is that the zero frequency you start with is not valid in frequency domain. Cheers Edgar

Jaime Guilherme Leal Alves

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Posted: 5 years ago 2020年3月27日 GMT-4 20:41

My guess is that the zero frequency you start with is not valid in frequency domain.

Cheers Edgar

It was not enough to evaluate the results. The same mistake happened.

>My guess is that the zero frequency you start with is not valid in frequency domain. > >Cheers >Edgar It was not enough to evaluate the results. The same mistake happened.

Edgar J. Kaiser Certified Consultant

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Posted: 5 years ago 2020年3月28日 GMT-4 08:16
Updated: 5 years ago 2020年3月28日 GMT-4 08:29

Well, as I said this was a guess. For anything beyond guessing we would need to see the model.

-------------------
Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
Well, as I said this was a guess. For anything beyond guessing we would need to see the model.

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