Hi

I have set up a case in which I have opening & total pressure at the inlet, and opening & static pressure at the outlet. I am running compressible simulation. Is it ok to use openings at both ends with compressible simulation?

If I do not use opening on either end, I get a message from solver stating "A wall has been placed the outlet/inlet". Under what circumstances one can ignore this message. Thank you.

Hi, Assuming a subsonic flow, you should check with the following

Subsonic Inlet: 4 characteristics go in (u,u,u,u+c) 1 characteristics go out (u-c) You need to feed in information about 4 variables. Usually density is left out

Subsonic Outlet: 1 characteristics go in (u-c) 4 characteristics go out (u,u,u,u+c) One boundary condition need to be fixed. Can be anything. Usually pressure in case of nozzle flows.

Open boundaries need to be used for these BCs.