[ghorrocks]

Thank you karachun...but I expected more help...

People answer questions on the forum because they like helping people. If you expect a more complete answer then you can pay for it and talk to ANSYS Support. Demanding answers from the forum is only going to get your question ignored.

Alexander has missed mentioning one important way of making simulations faster - which is to go parallel (or add more parallel nodes if you are already parallel).

[pashazanousi]

Thanks Karachun for your attention and your time spent
I mean coding is programming for Boundary value problem of solution in Matlab or some other software...
the solution is in a infinite time when the system reach a stable state...You definitely know the time dependent part of solution frequency is known and we assume a Sinusoid wave...I need the boundary value problem part of solution...I'm trying use CFX to solve it...May be I should programming a CFD code in Matlab...If you have a idea I will be happy to read about it...
Thank you all

[ghorrocks]

You may well be able to speed this up using boundary element methods, spectral methods, modal analysis or any of the myriad of other methods out there. But CFX supports none of this, it can only do steady state and transient (ie time domain) simulations.... Although noting it does have a frequency domain model for rotating machinery.

But it sounds like you should forget CFX and look at all the other approaches. But this is the CFX forum, so we won't be able to help you much there.

[pashazanousi]

I know this question was long ago, but It is worth saying that I solved my problem using Ansys's Acoustic harmonic module, using a FEM-based solver, instead of CFX, which is a CFD-based solver. Ansys's Acoustic harmonic can accurately simulate harmonic loads and boundary conditions. Although this method is based on FEM, not CFD, It is a promising method to study FSI under harmonic loads. If you need to investigate a thermal or electrical field simultaneously with the acoustic field, use Ansys Coupled Field Harmonic.