[hg2lf]

hello,foamers,
I'm trying to calculate a nozzle flow using rhoCentralFoam. We know that in the entry of a laval nozzle,the flow is subsonic,and speeded to supersonic at the exit.
I set the initial condition like this(I just calculate half of a nozzle):
inlet:fixedValue(p:1e5;T:1800;U:10);
outlet:T/U:zeroGradient;P:fixedValue:1000;
Wall:T/p:zeroGradient;U:fixedValue(0 0 0)
sym:symmetryPlane;

when I run rhoCentralFoam, ""maximum number of iterations exeeded" appear at the first time step.But if I chane the entry and the internal field of U to 1000m/s,the calculation could go on.
In fact, rhoCentralFoam could solve forwardstep flow,which is consisted of both subsonic and supersonic flow.
So,could someone give me some advice to solve the problem to calculate the laval nozzle flow?
Thanks a lot.