Fluent Propeller Noise Simulation with Permeable FW-H Sources

[kym.visyon]

I am simulating propeller noise in ANSYS Fluent 2023 R2 and would like to capture broadband noise using the FW-H model with a permeable surface.

My case:

• Propeller, sliding mesh, transient RANS then LES
• V = 20 m/s, tip Mach ≈ 0.46
• Goal: tonal + broadband noise

Questions:

1. In Fluid Flow (Fluent), how do I correctly create a permeable FW-H surface?
• Should it be defined inside Fluent or in DesignModeler?
2. What is the recommended shape and size?
• Is a cylindrical surface around the whole propeller appropriate?
• How large should it be relative to the propeller and rotating domain?
3. For two propellers in tandem, should the permeable surface enclose both propellers and their interacting wakes, or should each propeller have its own permeable surface?

Any guidance on the correct workflow in Fluent 2023 R2 would be appreciate