[evelknevel]

Hey guys,

I programmed a little solver for solving the compressible Reynoldsequation.

 surfaceScalarField  phis = fvc::interpolate(U*h/(R*T)) & mesh.Sf();
 
 { 
     tmp<fvScalarMatrix> PEqn 
       (            
          fvm::laplacian(p*(pow(h,3))/ (12 * (nu)),p)  
 
        - fvc::div(phis,p)  
         );
   
   PEqn().solve();

For a high velocity of the shaft i get highly oscillating results. With a really really low relaxation (0.0001) its converge very slow to the expected Values for p.

My schemes i use are:

divSchemes
{
    default     none;
  div((interpolate(((Uwelle*h)|(R*T)))&S),p) Gauss upwind;
     
}
laplacianSchemes
{
    default         Gauss linear corrected;
    laplacian(((rho*pow(h,3))|(12*nu)),p) Gauss linear corrected;
    }

I tried to use an upwind scheme for the laplacian term as well but i got some Errors.
How can i discretize the laplacian term with an upwind scheme, and do you have some other ideas to get it stable ?

Thanks,
Daniel