[robdeb]

Hi everybody!

I'm trying to simulate a subsonic flow in a nozzle.
I've tried to do this with rhoCentralFoam but the simulation didn't give good results. I don't know if it comes from my BC's or if rhoCentralFoam can't deal with subsonic flow.

I've attached my 0 folder to show you my BC's.

Thank you for your help.

[treima]

Hello,

what do you mean when you say "no good results"? Don´t they reach a steady state or anything else?


regards
treima

[robdeb]

After one iteration, I've got a Mach number of 0.43 but I know after analytical calculations that my maximum Mach number has to be more or less 0.1 at steady state.

Thank you!

[mturcios777]

Your case looks like its adapted from a 2D case. If this is what you want, then the frontAndBack boundaries should be of tpe "empty" for all your variables; in some of them they are "empty", in some they are "zeroGradient".

[treima]

For a Mach number about 0.1, is it really necessary to use a compressible solver?

[robdeb]

Originally Posted by treima

For a Mach number about 0.1, is it really necessary to use a compressible solver?

Yes, you're right. But what I would like to do is to test different solvers for different flows. I've already tested sonicFoam for a large range of Mach Number (subsonic to supersonic flows). It works good. And now I would like to test with rhoCentralFoam and compare the results.

[robdeb]

Originally Posted by mturcios777

Your case looks like its adapted from a 2D case. If this is what you want, then the frontAndBack boundaries should be of tpe "empty" for all your variables; in some of them they are "empty", in some they are "zeroGradient".

Yes, it's adapted from a 2D case. I'll test your boundaries and see what it gives.

Thank you for your advise.