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Acoutics Module

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I am trying to model a sound source (speaker, just a "power point source" now) in a sphere and prove that the sound is concetrated in the center of the sphere. Then I want to add sound treatment to the walls to get rid of that effect.

I just started using this program, so I am getting the following errors just trying to model the sphere and sound source.

Failed to evaluate operator.
-Operator: mean
-Geometry:1
-Boundary: 5,6,7,8,11,12,14,15
Mean operator requires an adjacent entity of higher dimension
Failed to evaluate expression
-Expression: mean(mod1.acsl.c_c)
Failed to evaluate variable
-Variable: mod1.acsl.ik
-Defined as: (mod1.ascl.iomega/mod1.acsl.c_c)

Please help! I need some ideas on where to start.


1 Reply Last Post 21 giu 2013, 09:55 GMT-4

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Posted: 1 decade ago 21 giu 2013, 09:55 GMT-4
Hello,

I am sure there will be some other feedback on your model but to get you started I have prepared some comments depending on what I have seen, and they are as follows:

1- In the geometry tab, you have prepared two sphares sharing the same volume. If I am not mistaken you wanted to create a hard surrounding material for your air domain. You need to add a Boolean operation for those two spheres to introduce the interraction surface between the two domains/materials.

2- I have seen that you have used Spherical wave radiaton over the boundaries of your air domain. As far as I understand, it contradicts with what you want to observe if you want to see the reflected waves inside your air domain, therefore I just disabled it.

3- In your mesh, the Free Triangular option is used for surface/boundary meshing however what you have is a 3D object, therefore I have used Free tetrahedral option to mesh your domains.

I hope this will give you an initial idea to move further?

/Onur
Hello, I am sure there will be some other feedback on your model but to get you started I have prepared some comments depending on what I have seen, and they are as follows: 1- In the geometry tab, you have prepared two sphares sharing the same volume. If I am not mistaken you wanted to create a hard surrounding material for your air domain. You need to add a Boolean operation for those two spheres to introduce the interraction surface between the two domains/materials. 2- I have seen that you have used Spherical wave radiaton over the boundaries of your air domain. As far as I understand, it contradicts with what you want to observe if you want to see the reflected waves inside your air domain, therefore I just disabled it. 3- In your mesh, the Free Triangular option is used for surface/boundary meshing however what you have is a 3D object, therefore I have used Free tetrahedral option to mesh your domains. I hope this will give you an initial idea to move further? /Onur

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