[Rundeli]

Hello all:

I am trying to set up a 3D numerial water channel which contains particles in the middle part using DPMFoam v2412.

My case setup is as follows:

0/U.water:

internalField   uniform (0 0 0);

boundaryField
{
    bottom
    {
        type            noSlip;
    }

    top
    {
       type            noSlip;
    }

    inlet
    {
        type            fixedValue;
        value           uniform (5 0 0);
    }

    outlet
    {
        type            zeroGradient;
    }

    frontAndBack
    {
        type            symmetry;
    }
}

0/p:

internalField   uniform 0;

boundaryField
{
    inlet
    {
        type            fixedFluxPressure;
        phi             phi.water;
        value           $internalField;
    }

    bottom
    {
        type            zeroGradient;
    }

    top
    {
        type            zeroGradient;
    }

    outlet
    {
        type            fixedValue;
        value           uniform 0;
    }

    frontAndBack
    {
        type            symmetry;
    }
}]

constant/kinematicCloudProperties:

solution
{
    active          true;
    coupled         true;
    transient       yes;
    cellValueSourceCorrection on;

    interpolationSchemes
    {
        rho.water         cell;
        U.water           cellPoint;
        mu.water          cellPoint;
        DUcDt             cellPoint;
    }

    integrationSchemes
    {
        U            Euler;
    }

    sourceTerms
    {
        schemes
        {
            U semiImplicit 1;
        }
    }
}

constantProperties
{
    parcelTypeId 1;

    rhoMin          1e-15;
    minParcelMass   1e-15;

    rho0            2526;
    youngsModulus   5e6;
    poissonsRatio   0.45;

    constantVolume  false;

    alphaMax        0.9;
}

subModels
{
    particleForces
    {
        ErgunWenYuDrag
        {
            alphac alpha.water;
        }
        gravity;
    }

    injectionModels
    {
        model1
        {
            type            manualInjection;
            massTotal       0;
            parcelBasisType fixed;
            nParticle       1;
            SOI             0;
            positionsFile   "kinematicCloudPositions";
            U0              (0 0 0);
            sizeDistribution
            {
                type        fixedValue;
                fixedValueDistribution
                {
                    value   0.0004;
                }
            }
        }
    }

    packingModel none;

    dispersionModel none;

    patchInteractionModel multiInteraction;
    multiInteractionCoeffs
    {
        oneInteractionOnly false;

        model1
        {
            patchInteractionModel localInteraction;
            localInteractionCoeffs
            {
                patches
                (
                    "(bottom|frontAndBack|top)"
                    {
                        type rebound;
                        e 0.91;
                        mu 0.17;
                    }
                    "(outlet|inlet)"
                    {
                        type none;
                    }   
                );
            }
        }

        model2
        {
            patchInteractionModel periodInteraction;
            periodInteractionCoeffs
            {
                recyclePatches
                (
                    (inlet outlet)
                );
                recycleFraction 1;
            }
        }
       
    }

    surfaceFilmModel none;

    collisionModel pairCollision;

    pairCollisionCoeffs
    {
        maxInteractionDistance  0.0002;

        writeReferredParticleCloud no;

        pairModel pairSpringSliderDashpot;

        pairSpringSliderDashpotCoeffs
        {
            useEquivalentSize   no;
            alpha               0.02;
            b                   1.5;
            mu                  0.10;
            cohesionEnergyDensity 0;
            collisionResolutionSteps 12;
        };
    
        wallModel wallSpringSliderDashpot;

        wallSpringSliderDashpotCoeffs
        {
            useEquivalentSize no;
            collisionResolutionSteps 12;
            youngsModulus   1e10;
            poissonsRatio   0.23;
            alpha           0.01;
            b               1.5;
            mu              0.09;
            cohesionEnergyDensity 0;
        };

        U     U.water;
    }

    stochasticCollisionModel none;
}


cloudFunctions
{

}

with timestep of 5e-7 and this is the result of 1e-5 which is clearly not realistic.

velocity field with particles:
up.jpg

velocity field:
u.jpg

pressure field:
p.jpg

what is wrong with my case setup ?