[ufocfd]

rhoSimplecFoam convergence seems to be very dependent on the relaxation factors. Wrong relaxation factors and the solution Nans or diverges! These URFs work well for me (see convergence pic below)
transonic=ON, Mach 0.7 case.

fields:
p 0.3;
rho 0.1;
equations:
U 0.7;
h 0.7;
k 0.5;
omega 0.5;