[sjohn2]

I am using the interfaceCompositionPhaseChangeTwoPhaseSystem, model to phase change from water to steam using the saturation pressure which is computed using Antoine equation. I checked that the coefficients A,B and C using a seperate code they seem to be accurate. Please have a look at my phaseProperties file:

PHP Code:

 /*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
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     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    location    "constant";
    object      phaseProperties;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

 
type  interfaceCompositionPhaseChangeTwoPhaseSystem; 

phases (gas liquid);

phaseChange on;

gas
{
    type            multiComponentPhaseModel;
    diameterModel   isothermal;
    constantCoeffs
    {
        d               0.00045;
    }

    isothermalCoeffs
    {
        d0               0.00045;
        p0              1e5;
    }
    Sc              0.7;

    residualAlpha   1e-4;
}

liquid
{
    type            multiComponentPhaseModel;
    diameterModel   constant;
    constantCoeffs
    {
        d               0.00045;
    }
    Sc              0.7;

    residualAlpha   1e-4;
}

blending
{
    default
    {
        type            linear;
        minFullyContinuousAlpha.gas 0.7;
        minPartlyContinuousAlpha.gas 0.3;
        minFullyContinuousAlpha.liquid 0.7;
        minPartlyContinuousAlpha.liquid 0.3;
    }
 
     heatTransfer
    {
        type            linear;
        minFullyContinuousAlpha.gas 1;
        minPartlyContinuousAlpha.gas 0;
        minFullyContinuousAlpha.liquid 1;
        minPartlyContinuousAlpha.liquid 0;
    }
 
        massTransfer
    {
        $heatTransfer;
    }
}


surfaceTension
( 

(gas and liquid)
    {
        type            constant;
        sigma           0.07;
    }

    
);

aspectRatio
(
    (gas in liquid)
    {
        type            constant;
        E0              1.0;
    }

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


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

    (liquid in gas)
    {
        type            SchillerNaumann;
        residualRe      1e-3;
        swarmCorrection
        {
            type        none;
        }
    }
);

virtualMass
(
    (gas in liquid)
    {
        type            constantCoefficient;
        Cvm             0.5;
    }
    
        (liquid in gas)
    {
        type            constantCoefficient;
        Cvm             0.5;
    }
);


interfaceComposition
( 
(gas in liquid)
    {
        type saturated;
        species (water);
        Le 1.0;
        saturationPressure
        {
            type Antoine;
            A 23.640509179;
            B -4170.59482;
            C -28.285;
        }
    }    
);



heatTransfer.gas
(
    (gas in liquid)
    {
        type spherical;
        residualAlpha 1e-3;
    }
);

heatTransfer.liquid
(
    (gas in liquid)
    {
        type RanzMarshall;
        residualAlpha 1e-3;
    }
);

 
massTransfer.gas
(
    (gas in liquid)
    {
        type spherical;
        Le 1.0;
    }

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

massTransfer.liquid
(
    (gas in liquid)
    {
        type Frossling;
        Le 1.0;
    }

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

phaseTransfer
();

lift
();

wallLubrication
();

turbulentDispersion
(
    (gas in liquid)
    {
        type                Burns;
        sigma               0.7;
        Ctd                 1.0;
        residualAlpha       1e-3;
    }
);

// Minimum allowable pressure
pMin            10000;


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


Other important files are the

PHP Code:

/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  6
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    location    "constant";
    object      thermophysicalProperties.liquid;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

species
(
    water
);
 

water
{
    specie
    {
        molWeight       18.0153;
    }
    equationOfState
    {
        R           461.9;
        rho0        917.938;
    }
    thermodynamics
    {
        Hf          0;
        Cp          4195;
    }
    transport
    {
        mu          0.1839239e-3;
        Pr          2.289;
    }
}


 


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


PHP Code:

/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  6
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    location    "constant";
    object      thermophysicalProperties.gas;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

species
(
    water
);
 

water
{
    specie
    {
        molWeight       18.0153;
    }
    
    equationOfState
    {
        R           461.9;
        rho0        917.938;
    }
    
    thermodynamics
    {
        Hf          0;
        Cp          1901;
    }
    transport
    {
        mu          1.2256e-5;
        Pr          2.289;
    }
}

 

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


The simulation works fine and converges and I do see the pressures dropping below saturation values in the nozzle but there is no apparent mass transfer.


Does anyone have an idea what might be wrong?
How do I output an variable pSat tmp<volScalarField> that is used in the computations just to check if my saturation pressure is being computed properly?

[sjohn2]

Please see attached my pressure plot. The correct calculated saturation pressure value is 4.6e5 and the pressure values within my nozzle is easily below that. Not sure why the phase change is being triggered.

I have also checked the densities of individual densities and they are close to expected values.

[sjohn2]

Here are rest of the files for setup:


alpha.liquid

PHP Code:

/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  6
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    location    "0";
    object      alpha.liquid;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 0 0 0 0 0 0];

internalField   uniform 1 ;

boundaryField
{
    INLET
    {
      type          fixedValue;
      value          uniform 1;
    }

    OUTLET
    {
     type       zeroGradient;
     
    }

    WALL
    {
        type       zeroGradient;
    }
}



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


alpha.gas

PHP Code:

/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  6
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    location    "0";
    object      alpha.gas;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 0 0 0 0 0 0];

internalField   uniform 0;

boundaryField
{
    INLET
    {
      type          fixedValue;
      value          uniform 0;
    }

    OUTLET
    {
       type            zeroGradient;
     
    }

    WALL
    {
        type            zeroGradient;
    }
}


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


mass fractions:

water.gas

PHP Code:

/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  6
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    location    "0";
    object      water.gas;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 0 0 0 0 0 0];

internalField   uniform 1e-8;

boundaryField
{
    INLET
    {
        type            fixedValue;
        value           $internalField;
    }
    OUTLET
    {
        type            inletOutlet;
        phi             phi.gas;
        inletValue      $internalField;
        value           $internalField;
    }
    WALL
    {
        type            zeroGradient;
    }
}

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


water.liquid

PHP Code:

/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  6
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    location    "0";
    object      water.liquid;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 0 0 0 0 0 0];

internalField   uniform 1e-8;

boundaryField
{
    INLET
    {
        type            fixedValue;
        value           $internalField;
    }
    OUTLET
    {
        type            inletOutlet;
        phi             phi.gas;
        inletValue      $internalField;
        value           $internalField;
    }
    WALL
    {
        type            zeroGradient;
    }
}

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


[sjohn2]

All the setup files.

CD_NOZ_3D_rtpef_BNL_291_gon_vm_eq_p_bc_pin_prghtotal_phasechange_test_upload.tar.gz

[sjohn2]

Further look at the results just after one timestep:

Solving the species transport equation yields mass fraction for water.liquid and water.gas of 1 throughout the domain. So I did output the source terms Su and Sp which is attached below.

From these I can find the interface species fraction Yf, which is also attached.

From the values of Su and Sp, I still cannot figure out why the mass fractions of the species water in both the phases turn to 1 after 1 timestep

Sp_t1.jpg

Su_t1.jpg

water.gas.t1.png

water.liquid.t1.jpg

[sjohn2]

I have narrowed down the problem, to the temperature in the gas phase dropping down near the inlet due to pressure drop. Please find attached figure.
Cannot figure why this is happening ??




Tgas.png

[sjohn2]

This problem has been resolved in the latest developmental version

[Vitor Monteiro]

Originally Posted by sjohn2

This problem has been resolved in the latest developmental version

Please, could you inform what version you were using (facing tha problem) and what version you are using now (with the problem solved)?

[杨星辰]

I'm also want to know this question.