CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   OpenFOAM Running, Solving & CFD (https://www.cfd-online.com/Forums/openfoam-solving/)
-   -   Compressible flow issues in rhoCentralFoam solver (https://www.cfd-online.com/Forums/openfoam-solving/186327-compressible-flow-issues-rhocentralfoam-solver.html)

sibo April 16, 2017 17:51
Compressible flow issues in rhoCentralFoam solver
 
4 Attachment(s)
Dear All,

I was using rhoCentralFoam solver to calculate the compressible flow around an airfoil. Ma=0.75, T=260K and P=85000.
The simulation looks good at the beginning, the pressure plot at the beginning is posted here.
But since the simulation does not converge, i keep it running and something weird happened here. As shown in the picture, the cells next to the inlet boundary has a very high temperature and pressure. Also, the shock at the airfoil looks more dissipated than before.

Can anybody help me with this? Thanks in advance!

sibo April 16, 2017 17:54
boundary conditions
 
The boundary conditions I am using in this case:
P:
Code:
boundaryField
{
    inlet
    {
        type            fixedValue;
        value          uniform 85418.9;
    }

    outlet
    {
        type            zeroGradient;
      // value          uniform 85418.9;
    }

    walls
    {
        type            slip;
    }

    defaultFaces
    {
        type            empty;
    }
}
U:
Code:
boundaryField
{
    inlet
    {
        type            freestream;
        freestreamValue uniform (241.84 16.84 0);
    }

    outlet
    {
        type            freestream;
        freestreamValue uniform (241.84 16.84 0);
    }

    walls
    {
        type            slip;
        //type            fixedValue;
        //value          uniform (0 0 0);
    }

    defaultFaces
    {
        type            empty;
    }
}
T:
Code:
boundaryField
{
    inlet
    {
        type            fixedValue;
        value          uniform 260;
    }

    outlet
    {
        type            zeroGradient;
      // value          uniform 260;
    }

    walls
    {
        type            slip;
    }

    defaultFaces
    {
        type            empty;
    }
}

sibo April 16, 2017 17:55
fvSchemes and fvSolutions
 
fvSchemes:
Code:
fluxScheme      Kurganov;

ddtSchemes
{
    default        Euler;
}

gradSchemes
{
    default        Gauss linear;
}

divSchemes
{
    default        Gauss upwind;
  //  div(phi,nuTilda) Gauss linearUpwind grad(nuTilda);
    div(tauMC)      Gauss linear;
}

laplacianSchemes
{
    default        Gauss linear corrected;
}

interpolationSchemes
{
    default        linear;
    reconstruct(rho) Gamma  1.0;
    reconstruct(U)  GammaV 1.0;
    reconstruct(T)  Gamma  1.0;
}

snGradSchemes
{
    default        corrected;
}
fvSolutions:
Code:
solvers
{
    rho
    {
        solver          diagonal;
    }

    rhoU
    {
        solver          diagonal;
    }

    rhoE
    {
        solver          diagonal;
    }

    U
    {
        solver          smoothSolver;
        smoother        GaussSeidel;
        nSweeps        2;
        tolerance      1e-09;
        relTol          0.01;
    }

    e
    {
        $U;
        tolerance      1e-08;
        relTol          0.01;
    }
}

sibo April 23, 2017 23:09
Modified Bcs and it works now.

ousoweak May 6, 2017 04:17
Quote:
Originally Posted by sibo (Post 646073)
Modified Bcs and it works now.
hi sibo

Which BC has you changed ,can you post your case here? Thanks~

Yiming

sibo May 10, 2017 17:19
Quote:
Originally Posted by ousoweak (Post 647856)
hi sibo

Which BC has you changed ,can you post your case here? Thanks~

Yiming
I used totalpressure for pressure. Also pay attention to the grid.


All times are GMT -4. The time now is 15:17.