[levivad]

I'm simulating an unsteady, low Mach number (M<0.1) flow. I also want to measure the generated sound.
I know that to find the sound caused by vortices I must enclose them by a "permeable surface" and define it as the sound source.
This also means that I must use compressible simulations with the ideal gas law.

The question remaining is whether I must reduce the time step to achieve a Currant number less then 1, even if the flow frequency is very small?

Since I'm capturing the boundary layer, this will cause a time step 3 orders of magnitude smaller then the flow time scale.

[HPUR]

Hi! I'm trying to simulate jet noise in subsonic nozzles and I came across your post here.I would like to know how I can introduce an acoustic permeable surface in order to enclose the noise sources along my computational domain.I appreciate it if you could give me some guidance about it.

[jasonbot]

Originally Posted by HPUR

Hi! I'm trying to simulate jet noise in subsonic nozzles and I came across your post here.I would like to know how I can introduce an acoustic permeable surface in order to enclose the noise sources along my computational domain.I appreciate it if you could give me some guidance about it.

Create a new named selection in your geometry/mesh that encloses your model.