This video shows how to get a Transmission Loss (TL) of a perforated media (glass wool) using the JCA model. All walls are defined as a rigid wall condition. And then sorry, this video has some errors (contact condition, Port of source).
Hi, thanks for great video I just have one question, what does Viscous and Thermal Characteristic Length mean? I am trying to do similar analysis but I dont know what sould I input into these parameters. Thank you
Thanks for sharing. Very useful material indeed! I've got a related question, I modelled two chabers and a concrete wall between to see the sound isolation. However, I am forced to choose a rigid zone and i cant select the concrete wall as acoustic zone to have the sound transfer inside the wall, yet here you have 3 objects and all bodies are acoustic and no rigid body eith solid element described. What would be the problem of my model that I can't have all bodies as acoustic region?
The model shown in the video has the following configuration Pure acoustic domain - Porous acoustic domain - Pure acoustic domain The porous acoustic region is a solid region, like a sponge, but it has microscopic hollow spaces inside which sound waves are transmitted. To generate the transmission of sound waves in a porous region, set it as an acoustic region and use the JCA model to apply the characteristics of the porous region. However, the concrete wall is a dense solid region. It cannot be set as an acoustic domain. It is recommended to set it as an FSI problem. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-YN-ZQzwFE0E.htmlsi=pByA9ML7uPC7vjVO
We suggest the following Create three regions with a node sharing model. [Acoustic region]-[Structural region]-[Acoustic region] In the Acoustic region, define material properties for air density and sound velocity. In the Structural region, define material properties for density, elastic modulus, and Poisson's ratio. For the constraint of Structural region, enter 0 for x, y, and z as the Displacement Support condition. Never use Fixed Support. This will result in zero PRES degrees of freedom. Set an FSI condition on the surface of the Acoustic region that is in contact with the Structural region.
@@jonghak.lee_simulation Many thanks for detailed reply! Can you please also mention that for the FSI, in these cases, what type of contact is recommended? bonded, frictional, etc... ?
This is a very interesting tutorial, when I run this tutorial I got the following error similar to your video. “The input power at the driven port is zero” same as in your video tutorial at 13:20. How can I fix this error?
I don't remember exactly. However, it did not hide the setting to correct errors in the video. So, if the settings are the same as in the video, the error should be resolved.
