[vaina74]

I'm going to study the aerodynamic aspect of ship superstructures. I started with a simple 2D model (see pic 1-2), a top view of a superstructure (abot 30x80 m). I used the simpleFoam solver (with wall functions) and I'd like to have some suggestions. I already studied airfoils and propeller blades in water (convergence before 1000 iterations and correct y+), but now I think I have a few problems about convergence and y+. Here are my boundary conditions:
p

#include        "initialConditions"

dimensions      [0 2 -2 0 0 0 0];

internalField   uniform $pressure;

boundaryField
{
    inlet
    {
        type            zeroGradient;
    }

    #include "frontBackPatches"

    outlet
    {
        type            fixedValue;
        value           $internalField;
    }

    main_body
    {
        type            kqRWallFunction;
        value           $internalField;
    }
}

U

#include        "initialConditions"

dimensions      [0 1 -1 0 0 0 0];

internalField   uniform $flowVelocity;

boundaryField
{
    #include "fixedInlet"

    #include "frontBackPatches"

    outlet
    {
        type            inletOutlet;
        inletValue      uniform (0 0 0);
        value           $internalField;
    }

    main_body
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
}

k

#include        "initialConditions"

dimensions      [0 2 -2 0 0 0 0];

internalField   uniform $turbulentK;

boundaryField
{
    #include "fixedInlet"

    #include "frontBackPatches"

    main_body
    {
        type            kqRWallFunction;
        value           $internalField;
    }

    outlet
    {
        type            inletOutlet;
        inletValue      $internalField;
        value           $internalField;
    }
}

omega

#include        "initialConditions"

dimensions      [0 0 -1 0 0 0 0];

internalField   uniform $turbulentOmega;

boundaryField
{
    #include "fixedInlet"

    #include "frontBackPatches"

    main_body
    {
        type            kqRWallFunction;
        value           $internalField;
    }

    outlet
    {
        type            inletOutlet;
        inletValue      $internalField;
        value           $internalField;
    }
}

My system settings are:

FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      fvSchemes;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

ddtSchemes
{
    default steadyState;
}

gradSchemes
{
    default         Gauss linear;
    grad(p)         Gauss linear;
    grad(U)         Gauss linear;
//    grad(U)         cellLimited Gauss linear 1;
}

divSchemes
{
    default         none;
    div(phi,U)      Gauss linearUpwindV Gauss linear;
    div(phi,k)      Gauss upwind;
    div(phi,omega)  Gauss upwind;
    div((nuEff*dev(grad(U).T()))) Gauss linear;
}

laplacianSchemes
{
    default         Gauss linear corrected;
//    default         Gauss linear limited 0.5;
//    default         Gauss linear limited 0.333;
}

interpolationSchemes
{
    default         linear;
    interpolate(U)  linear;
}

snGradSchemes
{
    default         corrected;
}

fluxRequired
{
    default         no;
    p;
}

and

FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      fvSolution;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

solvers
{
    p
    {
        solver           GAMG;
        tolerance        1e-7;
        relTol           0.1;
        smoother         GaussSeidel;
        nPreSweeps       0;
        nPostSweeps      2;
        cacheAgglomeration on;
        agglomerator     faceAreaPair;
        nCellsInCoarsestLevel 10;
        mergeLevels      1;
    };

    U
    {
        solver           smoothSolver;
        smoother         GaussSeidel;
        tolerance        1e-8;
        relTol           0.1;
        nSweeps          1;
    };

    k
    {
        solver           smoothSolver;
        smoother         GaussSeidel;
        tolerance        1e-8;
        relTol           0.1;
        nSweeps          1;
    };

    omega
    {
        solver           smoothSolver;
        smoother         GaussSeidel;
        tolerance        1e-8;
        relTol           0.1;
        nSweeps          1;
    };
}

SIMPLE
{
    nNonOrthogonalCorrectors 0;
    convergenceCriterion 1e-5;
}

relaxationFactors
{
    p               0.3;
    U               0.7;
    k               0.7;
    omega           0.7;
}

Maybe the mesh is bad, but I tried to refine it and I obtain worse , and y+. Any suggestions about domain dimensions, fvSchemes, initial conditions (=0.015 and =80) and so on?

I thought about a different mesh (see pic3) but I'm in troubles with inlet and outlet boundary conditions for p and U. I'd like to set different apparent winds, so I believe I can't establish which patch is an inlet or outlet one beforehand. Are there any derived boundary conditions, similar to inletOutlet and outletInlet, to that aim?

Thanks for your help.