[cassio]

Hi All,


I'm trying to simulate the drying of water present in one phase. For that, I'm using the multiphaseEulerFoam solver in Openfoam8.


The problem I found is that the two species (“fibras” “H2O”) present in the phase (particles) are losing mass.


phaseProperties

type    interfaceCompositionPhaseChangeMultiphaseSystem;



phases (particles gas);


particles
{
    type           multiComponentPhaseModel;

    diameterModel constant;    
    constantCoeffs
    {
        d              1e-2;
    }

    alphaMax        0.62;
    residualAlpha   1e-6;
}

gas
{
    type          multiComponentPhaseModel;

    diameterModel constant;
    constantCoeffs
    {
        d               1;
    }

    residualAlpha   0;
}

blending
{
    default
    {
    type            linear;
        minFullyContinuousAlpha.gas 0.7;
        minPartlyContinuousAlpha.gas 0.3;
        minFullyContinuousAlpha.particles 0.7;
        minPartlyContinuousAlpha.particles 0.3;
    }

    heatTransfer
    {
        type            linear;
        minPartlyContinuousAlpha.gas 0;
        minFullyContinuousAlpha.gas 1;
        minPartlyContinuousAlpha.particles 0;
        minFullyContinuousAlpha.particles 1;
    }

    diffusiveMassTransfer
    {
        $heatTransfer;
    }

};

surfaceTension
(
    (gas and particles)
    {
        type            constant;
        sigma           0;
    }
);

aspectRatio
(

    (gas in particles)
    {
        type            constant;
        E0              1.0;
    }

    (particles in gas)
    {
        type            constant;
        E0              1.0;
    }

);



drag
(
    (particles in gas)
    {
        type            GidaspowErgunWenYu;
        residualRe      1e-3;
        swarmCorrection
        {
            type        none;
        }
    }


);

virtualMass
(

);

interfaceComposition.gas
(
    (gas and particles)
    {
        type saturated;        
        species ( "H2O" );    
        Le 1.0;
        saturationPressure
        {
            type ArdenBuck;
        }
    }
);

interfaceComposition.particles
(

);

heatTransfer.gas
(
    (gas in particles)
    {
        type            spherical;
        residualAlpha   1e-4;
    }

    (particles in gas)
    {
        type            RanzMarshall;
        residualAlpha   1e-4;
    }
);

heatTransfer.particles
(
    (gas in particles)
    {
        type            spherical;
        residualAlpha   1e-4;
    }

    (particles in gas)
    {
        type            RanzMarshall;
        residualAlpha   1e-4;
    }
);

diffusiveMassTransfer.gas
(
    (gas in particles)
    {
        type spherical;
        Le 1.0;
    }

    (particles in gas)
    {
        type Frossling;
        Le 1.0;
    }
);

diffusiveMassTransfer.particles
(
    (gas in particles)
    {
        type Frossling;
        Le 1.0;
    }

    (particles in gas)
    {
        type spherical;
        Le 1.0;
    }
);

phaseTransfer
(
);

lift
(
);

wallLubrication
(
);

turbulentDispersion
(
);

interfaceCompression
();

// Minimum allowable pressure
pMin            10000;


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

Any idea on how to fix this?


Thanks
Cassio


thermophysicalProperties.gas

thermoType
{
    type            heRhoThermo;
    mixture         multiComponentMixture;
    transport       sutherland;
    thermo          janaf;
    equationOfState perfectGas;
    specie          specie;
    energy          sensibleInternalEnergy;
}



species
(
    air
    H2O  
);

H2O
{
    specie
    {
        molWeight       18.0153;
    }
    thermodynamics
    {
        Tlow            200;
        Thigh           3500;
        Tcommon         1000;
        highCpCoeffs    ( 3.03399 0.00217692 -1.64073e-07 -9.7042e-11 1.68201e-14 -30004.3 4.96677 );
        lowCpCoeffs     ( 4.19864 -0.00203643 6.5204e-06 -5.48797e-09 1.77198e-12 -30293.7 -0.849032 );
    }
    transport
    {
        As              1.67212e-06;
        Ts              170.672;
    }
}

air
{
    specie
    {
        molWeight       28.9596;
    }
    thermodynamics
    {
        Tlow            200;
        Thigh           3500;
        Tcommon         1000;
        highCpCoeffs    ( 3.57304 -7.24383e-04 1.67022e-06 -1.26501e-10 -4.20580e-13 -1047.41 3.12431 );
        lowCpCoeffs     ( 3.09589 1.22835e-03 -4.14267e-07 6.56910e-11 -3.87021e-15 -983.191 5.34161 );
    }
    transport
    {
        As              1.67212e-06;
        Ts              170.672;
    }
}

thermophysicalProperties.particles

thermoType
{
    type            heRhoThermo;
    mixture         multiComponentMixture;
    transport       const;
    thermo          hConst;
    equationOfState rPolynomial;
    specie          specie;
    energy          sensibleInternalEnergy;

}


species
(
    fibras
    H2O

);


H2O
{

    specie
    {
        molWeight       18.0153;
    }
    equationOfState
    {

        C (0.001278 -2.1055e-06 3.9689e-09 4.3772e-13 -2.0225e-16);
    }
    thermodynamics
    {
        Cp          4195;
        Hf          -1.5879e+07;

    }
    transport
    {
        mu          3.645e-4;
        Pr          2.289;
    }
}

fibras
{
    specie
    {
        molWeight   9.72;
    }
    equationOfState
    {
        
        C (0.000680272108843537 0 0 0 0);
    }
    thermodynamics
    {
        Cp          3090;
        Hf          0;
    }
    transport
    {
        mu          0;
        Pr          1;
    }
}

p { margin-bottom: 0.25cm; line-height: 120% }

[Vitor Monteiro]

I'm facing the same problem, Cassio.

Using OF8 and the same solver, I could not avoid the "evaporation" of carbon.particles instead of H2O.particles only.

My continuous fase is composed by air.gas and H2O.gas.

So I just want H2O.particles turning into H2O.gas. However, carbon.particles species is also changing and "evaporating".



Does anyone know how to deal with it?