rhocentralFoam supersonic flow issues
 

Dear all,

I am now running a 2D axisymmetric supersonic impinging jet case using rhocentralFoam.

The current timestep is 8e-10s and CFL number is restricted to be less than 0.4. But results seems not correct. The pressure near the plate will be higher than the stagnation pressure. I have run this simulation very long for about 20 days already. However, the pressure is still sometimes larger than the stagnation pressure but it wont blow up. It seems like singularity points emerging near the plate or the axis sometimes, while the mesh is already very fine. The average y+ near the plate is below 2.

CheckMesh is done and no errors or warnings pop up.
BC should be correct. The only uncertainty is the axis should be empty or symmetry?

I found CFL number has to be less than 0.2 in other threads, but I found some papers using rhocentralfoam only below 0.5 for supersonic flows. I am quite confused how to select the CFL number for rhocentralfoam? I am also suspicious of my fvschemes and fvsolutions? Could anyone help me check it?

fvSolutions
solvers
{
"(rho|rhoU|rhoE)"
{
solver diagonal;
}

U
{
solver smoothSolver;
smoother GaussSeidel;
nSweeps 2;
tolerance 1e-09;
relTol 1e-05;
}

e
{
$U;
relTol 1e-05;
}
}

fvSchemes
fluxScheme Kurganov;

ddtSchemes
{
default backward;
}

gradSchemes
{
default Gauss linear;
}

divSchemes
{
default none;
div(tauMC) Gauss linear;
}

laplacianSchemes
{
default Gauss linear corrected;
}

interpolationSchemes
{
default linear;
reconstruct(rho) vanLeer;
reconstruct(U) vanLeerV;
reconstruct(T) vanLeer;
}

snGradSchemes
{
default corrected;
}


Any ideas please?

Really appreciate help from the Forum.

Thanks.

Sam