Stability in compressible pimple application
 

Hi all,

I started to implement an acoustic flow solver by using the Euler equations. Further I modified the rhoPimpleFoam solver and included the new set of equations. The theory of the acoustic solver follows the EIF Method which is been developed by Hardin and Pope.

The solver gives some resonable results but as the title describes, I have some problems concerning the stability of the system when I use time steps of co> 0.6. As a test case I calculate the radiation of a pressure impulse. Please find two pictures showing the instabilities attached.

Cane someone give me an advice about how to improve the stability for such kind of equation? If you need more information about my settings I will be happy to write them.

Thank you very much for your help.

Thilo