[AntonioMezzacapo]

Greetings all, I am carrying on an unsteady turbulent 3D wind turbine blade simulation, using rhoPimpleFoam solver. I noticed my simulation takes many time to run . I read somewhere I might use some preconditioner in order to speed my simulation up.
I used: solver PCG; preconditioner DIC; for pressure
solver PBiCGStab preconditioner DILU; for velocity

but after a while my time step decreaes and the simulation becames instable.
Do you have any advices in order to speed it up? Thanks!

  /*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  8
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
  
    format      ascii;
    class       dictionary;
    location    "system";
    object      fvSchemes;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

ddtSchemes
{
    default         Euler;
}

gradSchemes
{
    default         Gauss linear;

    limited         cellLimited Gauss linear 1;
    grad(U)         $limited;
    grad(k)         $limited;
    grad(omega)     $limited;
}

divSchemes
{
    default             none;
div(phi,h)          Gauss linearUpwind limited;
    div(phi,U)          Gauss linearUpwind limited;
 div(meshPhi,p)          Gauss linearUpwind limited;


    turbulence          Gauss linearUpwind limited;
    energy              Gauss linearUpwind limited;

    div(phi,k)          $turbulence;
    div(phi,omega)      $turbulence;

    div(phi,e)          $energy;
    div(phi,K)          $energy;
    div(phi,Ekp)        $energy;
  div(phi,(p|rho))    $energy;

div((phi|interpolate(rho)),p) Gauss upwind;

    div(((rho*nuEff)*dev2(T(grad(U))))) Gauss linear;
}

laplacianSchemes
{
    default         Gauss linear corrected;
}

interpolationSchemes
{
    default         linear;
}

snGradSchemes
{
    default         corrected;
}

wallDist
{
    method meshWave;
}
// ************************************************************************* //

  /*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  8
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
   
    format      ascii;
    class       dictionary;
    location    "system";
    object      fvSolution;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //


solvers
{
    p
    {
        solver          smoothSolver;
        smoother        symGaussSeidel;

        tolerance       1e-12;
        relTol          0.01;
    }

    pFinal
    {
        $p;
        relTol          0;
    }

    "pcorr.*"
    {
        $p;
        tolerance       1e-2;
        relTol          0;
    }

    "(rho|e|U|h|k|epsilon|omega|eFinal|ecorr.*)"
    {
        solver          smoothSolver;
        smoother        symGaussSeidel;
        tolerance       1e-06;
        relTol          0.1;
    }

    "(rho|U|h|k|epsilon|omega)Final"
    {
        $U;
        relTol          0;
    }

}

PIMPLE
{
    momentumPredictor   yes;
    transonic           no;
    nOuterCorrectors    3;
    nCorrectors         1;
    nNonOrthogonalCorrectors 0;
}

relaxationFactors
{
    equations
    {
        "(U|h|k|epsilon|omega).*" 1;
    }
}


// ************************************************************************* //