Initialization of compressible flows
 

Good evening everyone,



I am working on a compressible unsteady flow case that is conceptually similar to a flow inside a duct containing a bluff body and would like to know if there is a smart way to initialize the flow.



I know that unsteady simulation are such because the unknown is generally the response to some external forcing, but in this situation I just need a reasonable representation of what is going on behind the bluff body ( Von Karman vortex - which is intrinsically unsteady) and I do not really care how the system reaches the final state (which is unsteady but hopefully periodic).



If it were incompressible I would use potentialFoam, and then run rhoPimpleFoam but this procedure gives me an error (obviously since in the first the pressure is a sort of Lagrangian multiplier whereas in the latter it is actually a pressure and has different dimensions). Is there a way to initialize at least the U field by potentialFoam? How to do it?


I thought of mapFields utility too, that is reasonable if I had a previous simulation of the same kind which I have not (I have just the incompressible equivalent which suffers the same problem of the output of laplacianFoam).


Thanks in advance.