[saidc.]

Hi everyone,

I have problem which I can't solve. I've 2 different case with same geometry. One of them is simpleFoam (RAS) case and other pisoFoam (LES) case. I ran the simulations 15 seconds with their own solvers and the results looks good so there isn't any problem. But when I try particle-tracking with icoUncoupledKinematicParcelFoam some things are not going well.

Both case, my Reynolds number is 5e4 but if i change to this number in icoUncoupledKinematicParcelFoam the case run just a few step and stop. In any case, when I didn't change kinematic viscosity the loop didn't complete. I give 3 second but it run like 1.9 second.

pisoFoam is worse than simpleFoam. I mean, simpleFoam ran about 1.9 second at least. pisoFoam ran like 0.3 second and stop suddenly. Also there is no error.

Can someone who knows these situations give an idea? I am open to any advice.

This is gif of simpleFoam particle-tracking:
https://gfycat.com/energeticdecisivecurlew

simpleFoam

controlDict

application     icoUncoupledKinematicParcelFoam;

startFrom       latestTime;

startTime       0;

stopAt          endTime;

endTime         3;

deltaT          0.005;

writeControl    adjustableRunTime;

writeInterval   0.01;

purgeWrite      0;

writeFormat     ascii;

writePrecision  6;

writeCompression off;

timeFormat      general;

timePrecision   6;

runTimeModifiable yes;

kinematicCloudProperties

solution
{
    active          true;
    coupled         false;
    transient       yes;
    cellValueSourceCorrection off;
    maxCo           0.3;

    interpolationSchemes
    {
        rho             cell;
        U               cellPoint;
        mu              cell;
    }

    integrationSchemes
    {
        U               Euler;
    }
}

constantProperties
{
    rho0            1.2;
    youngsModulus   6e8;
    poissonsRatio   0.35;
}

subModels
{
    particleForces
    {
        sphereDrag;
        gravity;
    }

    injectionModels
    {
        model1
        {
            type            patchInjection;
            parcelBasisType fixed;
            patchName       inlet;
            nParticle       1;
            SOI             0;
            U0              (10 0 0);
            parcelsPerSecond 1000;
            sizeDistribution
            {
                type        normal;
                normalDistribution
                {
                    expectation 650e-6;
                    variance 25e-6;
                    minValue 500e-6;
                    maxValue 800e-6;
                }
            }
            flowRateProfile constant 1;
            massTotal       0;
            duration 100;
        }
    }

    dispersionModel none;

    patchInteractionModel none;

    surfaceFilmModel none;

    stochasticCollisionModel none;

    collisionModel none;

    pairCollisionCoeffs
    {
        maxInteractionDistance  0.0001;

        writeReferredParticleCloud no;

        pairModel pairSpringSliderDashpot;

        pairSpringSliderDashpotCoeffs
        {
            useEquivalentSize   no;
            alpha               0.12;
            b                   1.5;
            mu                  0.52;
            cohesionEnergyDensity 0;
            collisionResolutionSteps 12;
        };

        wallModel    wallLocalSpringSliderDashpot;

        wallLocalSpringSliderDashpotCoeffs
        {
            useEquivalentSize no;
            collisionResolutionSteps 12;
            upperWall
            {
                youngsModulus   1e10;
                poissonsRatio   0.23;
                alpha           0.12;
                b               1.5;
                mu              0.43;
                cohesionEnergyDensity 0;
            }
            lowerWall
            {
                youngsModulus   1e10;
                poissonsRatio   0.23;
                alpha           0.12;
                b               1.5;
                mu              0.43;
                cohesionEnergyDensity 0;
            }
            frontAndBack
            {
                youngsModulus   1e10;
                poissonsRatio   0.23;
                alpha           0.12;
                b               1.5;
                mu              0.1;
                cohesionEnergyDensity 0;
            }
        };
    }
}


cloudFunctions
{}

pisoFoam

controlDict

application     icoUncoupledKinematicParcelFoam;

startFrom       startTime;

startTime       0;

stopAt          endTime;

endTime         1;

deltaT          0.005;

writeControl    adjustableRunTime;

writeInterval   0.01;

purgeWrite      0;

writeFormat     ascii;

writePrecision  6;

writeCompression off;

timeFormat      general;

timePrecision   6;

runTimeModifiable yes;

kinematicCloudProperties

solution
{
    active          true;
    coupled         false;
    transient       yes;
    cellValueSourceCorrection off;
    maxCo           0.5;

    interpolationSchemes
    {
        rho             cell;
        U               cellPoint;
        mu              cell;
    }

    integrationSchemes
    {
        U               Euler;
    }
}

constantProperties
{
    rho0            1.2;
    youngsModulus   6e8;
    poissonsRatio   0.35;
}

subModels
{
    particleForces
    {
        sphereDrag;
        gravity;
    }

    injectionModels
    {
        model1
        {
            type            patchInjection;
            parcelBasisType fixed;
            patchName       inlet;
            nParticle       1;
            SOI             0;
            U0              (10 0 0);
            parcelsPerSecond 1000;
            sizeDistribution
            {
                type        normal;
                normalDistribution
                {
                    expectation 650e-6;
                    variance 25e-6;
                    minValue 500e-6;
                    maxValue 800e-6;
                }
            }
            flowRateProfile constant 1;
            massTotal       0;
            duration 1;
        }
    }

    dispersionModel none;

    patchInteractionModel none;

    surfaceFilmModel none;

    stochasticCollisionModel none;

    collisionModel none;

    pairCollisionCoeffs
    {
        maxInteractionDistance  0.0001;

        writeReferredParticleCloud no;

        pairModel pairSpringSliderDashpot;

        pairSpringSliderDashpotCoeffs
        {
            useEquivalentSize   no;
            alpha               0.12;
            b                   1.5;
            mu                  0.52;
            cohesionEnergyDensity 0;
            collisionResolutionSteps 12;
        };

        wallModel    wallLocalSpringSliderDashpot;

        wallLocalSpringSliderDashpotCoeffs
        {
            useEquivalentSize no;
            collisionResolutionSteps 12;
            upperWall
            {
                youngsModulus   1e10;
                poissonsRatio   0.23;
                alpha           0.12;
                b               1.5;
                mu              0.43;
                cohesionEnergyDensity 0;
            }
            lowerWall
            {
                youngsModulus   1e10;
                poissonsRatio   0.23;
                alpha           0.12;
                b               1.5;
                mu              0.43;
                cohesionEnergyDensity 0;
            }
            frontAndBack
            {
                youngsModulus   1e10;
                poissonsRatio   0.23;
                alpha           0.12;
                b               1.5;
                mu              0.1;
                cohesionEnergyDensity 0;
            }
        };
    }
}

cloudFunctions
{}

Stops like this

Time = 0.291

Evolving kinematicCloud

Solving 3-D cloud kinematicCloud

Cloud: kinematicCloud injector: model1
    Added 5 new parcels

Cloud: kinematicCloud
    Current number of parcels       = 1455
    Current mass in system          = 2.50729e-07
    Linear momentum                 = (1.9443e-07 4.27472e-08 1.03438e-12)
   |Linear momentum|                = 1.99073e-07
    Linear kinetic energy           = 1.09353e-07
    model1:
        number of parcels added     = 1455
        mass introduced             = 2.50729e-07
    Rotational kinetic energy       = 0

ExecutionTime = 260.49 s  ClockTime = 262 s

Time = 0.292

Evolving kinematicCloud

Solving 3-D cloud kinematicCloud

Cloud: kinematicCloud injector: model1
    Added 5 new parcels

Best regards,
Said.