ReactingMultiphaseParcel.C

Go to the documentation of this file.

/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Copyright (C) 2011-2024 OpenFOAM Foundation
     \\/     M anipulation  |
-------------------------------------------------------------------------------
License
    This file is part of OpenFOAM.
 
    OpenFOAM is free software: you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
 
    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    for more details.
 
    You should have received a copy of the GNU General Public License
    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
 
\*---------------------------------------------------------------------------*/
 
#include "ReactingMultiphaseParcel.H"
#include "CompositionModel.H"
#include "NoDevolatilisation.H"
#include "NoSurfaceReaction.H"
#include "mathematicalConstants.H"
 
using namespace Foam::constant::mathematical;
 
 
// * * * * * * * * * * * *  Private Member Functions * * * * * * * * * * * * //
 
template<class ParcelType>
template<class TrackCloudType>
Foam::scalar Foam::ReactingMultiphaseParcel<ParcelType>::CpEff
(
    TrackCloudType& cloud,
    trackingData& td,
    const scalar p,
    const scalar T,
    const label idG,
    const label idL,
    const label idS
) const
{
    return
        this->Y_[idG]*cloud.composition().Cp(idG, YGas_, p, T)
      + this->Y_[idL]*cloud.composition().Cp(idL, YLiquid_, p, T)
      + this->Y_[idS]*cloud.composition().Cp(idS, YSolid_, p, T);
}
 
 
template<class ParcelType>
template<class TrackCloudType>
Foam::scalar Foam::ReactingMultiphaseParcel<ParcelType>::hsEff
(
    TrackCloudType& cloud,
    trackingData& td,
    const scalar p,
    const scalar T,
    const label idG,
    const label idL,
    const label idS
) const
{
    return
        this->Y_[idG]*cloud.composition().hs(idG, YGas_, p, T)
      + this->Y_[idL]*cloud.composition().hs(idL, YLiquid_, p, T)
      + this->Y_[idS]*cloud.composition().hs(idS, YSolid_, p, T);
}
 
 
template<class ParcelType>
template<class TrackCloudType>
Foam::scalar Foam::ReactingMultiphaseParcel<ParcelType>::LEff
(
    TrackCloudType& cloud,
    trackingData& td,
    const scalar p,
    const scalar T,
    const label idG,
    const label idL,
    const label idS
) const
{
    return
        this->Y_[idG]*cloud.composition().L(idG, YGas_, p, T)
      + this->Y_[idL]*cloud.composition().L(idL, YLiquid_, p, T)
      + this->Y_[idS]*cloud.composition().L(idS, YSolid_, p, T);
}
 
 
template<class ParcelType>
Foam::scalar Foam::ReactingMultiphaseParcel<ParcelType>::updateMassFractions
(
    const scalar mass0,
    const scalarField& dMassGas,
    const scalarField& dMassLiquid,
    const scalarField& dMassSolid,
    const label idG,
    const label idL,
    const label idS
)
{
    scalarField& YMix = this->Y_;
 
    scalar massGas =
        this->updateMassFraction(mass0*YMix[idG], dMassGas, YGas_);
    scalar massLiquid =
        this->updateMassFraction(mass0*YMix[idL], dMassLiquid, YLiquid_);
    scalar massSolid =
        this->updateMassFraction(mass0*YMix[idS], dMassSolid, YSolid_);
 
    scalar massNew = max(massGas + massLiquid + massSolid, rootVSmall);
 
    YMix[idG] = massGas/massNew;
    YMix[idL] = massLiquid/massNew;
    YMix[idS] = 1.0 - YMix[idG] - YMix[idL];
 
    return massNew;
}
 
 
// * * * * * * * * * * *  Protected Member Functions * * * * * * * * * * * * //
 
template<class ParcelType>
template<class TrackCloudType>
void Foam::ReactingMultiphaseParcel<ParcelType>::setCellValues
(
    TrackCloudType& cloud,
    trackingData& td
)
{
    ParcelType::setCellValues(cloud, td);
}
 
 
template<class ParcelType>
template<class TrackCloudType>
void Foam::ReactingMultiphaseParcel<ParcelType>::cellValueSourceCorrection
(
    TrackCloudType& cloud,
    trackingData& td,
    const scalar dt
)
{
    // Reuse correction from reacting parcel
    ParcelType::cellValueSourceCorrection(cloud, td, dt);
}
 
 
template<class ParcelType>
template<class TrackCloudType>
void Foam::ReactingMultiphaseParcel<ParcelType>::calc
(
    TrackCloudType& cloud,
    trackingData& td,
    const scalar dt
)
{
    typedef typename TrackCloudType::thermoCloudType thermoCloudType;
    const CompositionModel<thermoCloudType>& composition =
        cloud.composition();
 
 
    // Define local properties at beginning of timestep
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
    const scalar np0 = this->nParticle_;
    const scalar d0 = this->d_;
    const vector& U0 = this->U_;
    const scalar T0 = this->T_;
    const scalar mass0 = this->mass();
 
    const scalar pc = td.pc();
 
    const scalarField& YMix = this->Y_;
    const label idG = composition.idGas();
    const label idL = composition.idLiquid();
    const label idS = composition.idSolid();
 
 
    // Calc surface values
    scalar Ts, rhos, mus, Prs, kappas;
    this->calcSurfaceValues(cloud, td, T0, Ts, rhos, mus, Prs, kappas);
    scalar Res = this->Re(rhos, U0, td.Uc(), d0, mus);
 
 
    // Sources
    //~~~~~~~~
 
    // Explicit momentum source for particle
    vector Su = Zero;
 
    // Linearised momentum source coefficient
    scalar Spu = 0.0;
 
    // Momentum transfer from the particle to the carrier phase
    vector dUTrans = Zero;
 
    // Explicit enthalpy source for particle
    scalar Sh = 0.0;
 
    // Linearised enthalpy source coefficient
    scalar Sph = 0.0;
 
    // Sensible enthalpy transfer from the particle to the carrier phase
    scalar dhsTrans = 0.0;
 
 
    // 1. Compute models that contribute to mass transfer - U, T held constant
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
    // Phase change in liquid phase
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
    // Mass transfer due to phase change
    scalarField dMassPC(YLiquid_.size(), 0.0);
 
    // Molar flux of species emitted from the particle (kmol/m^2/s)
    scalar Ne = 0.0;
 
    // Sum Ni*Cpi*Wi of emission species
    scalar NCpW = 0.0;
 
    // Surface concentrations of emitted species
    scalarField Cs(composition.carrier().species().size(), 0.0);
 
    // Calc mass and enthalpy transfer due to phase change
    this->calcPhaseChange
    (
        cloud,
        td,
        dt,
        Res,
        Prs,
        Ts,
        mus/rhos,
        d0,
        T0,
        mass0,
        idL,
        YMix[idL],
        YLiquid_,
        dMassPC,
        Sh,
        Ne,
        NCpW,
        Cs
    );
 
 
    // Devolatilisation
    // ~~~~~~~~~~~~~~~~
 
    // Mass transfer due to devolatilisation
    scalarField dMassDV(YGas_.size(), 0.0);
 
    // Calc mass and enthalpy transfer due to devolatilisation
    calcDevolatilisation
    (
        cloud,
        td,
        dt,
        Ts,
        d0,
        T0,
        mass0,
        mass0_,
        YMix[idG]*YGas_,
        YMix[idL]*YLiquid_,
        YMix[idS]*YSolid_,
        canCombust_,
        dMassDV,
        Sh,
        Ne,
        NCpW,
        Cs
    );
 
 
    // Surface reactions
    // ~~~~~~~~~~~~~~~~~
 
    // Change in carrier phase composition due to surface reactions
    scalarField dMassSRGas(YGas_.size(), 0.0);
    scalarField dMassSRLiquid(YLiquid_.size(), 0.0);
    scalarField dMassSRSolid(YSolid_.size(), 0.0);
    scalarField dMassSRCarrier(composition.carrier().species().size(), 0.0);
 
    // Calc mass and enthalpy transfer due to surface reactions
    calcSurfaceReactions
    (
        cloud,
        td,
        dt,
        d0,
        T0,
        mass0,
        canCombust_,
        Ne,
        YMix,
        YGas_,
        YLiquid_,
        YSolid_,
        dMassSRGas,
        dMassSRLiquid,
        dMassSRSolid,
        dMassSRCarrier,
        Sh,
        dhsTrans
    );
 
 
    // 2. Update the parcel properties due to change in mass
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
    scalarField dMassGas(dMassDV + dMassSRGas);
    scalarField dMassLiquid(dMassPC + dMassSRLiquid);
    scalarField dMassSolid(dMassSRSolid);
    scalar mass1 =
        updateMassFractions
        (
            mass0,
            dMassGas,
            dMassLiquid,
            dMassSolid,
            idG,
            idL,
            idS
        );
 
    this->Cp_ = CpEff(cloud, td, pc, T0, idG, idL, idS);
 
    // Update particle density or diameter
    if (cloud.constProps().constantVolume())
    {
        this->rho_ = mass1/this->volume();
    }
    else
    {
        this->d_ = cbrt(mass1/this->rho_*6.0/pi);
    }
 
    // Remove the particle when mass falls below minimum threshold
    if (np0*mass1 < cloud.constProps().minParcelMass())
    {
        td.keepParticle = false;
 
        if (cloud.solution().coupled())
        {
            scalar dm = np0*mass0;
 
            // Absorb parcel into carrier phase
            forAll(YGas_, i)
            {
                label gid = composition.localToCarrierId(idG, i);
                cloud.rhoTrans(gid)[this->cell()] += dm*YMix[idG]*YGas_[i];
            }
            forAll(YLiquid_, i)
            {
                label gid = composition.localToCarrierId(idL, i);
                cloud.rhoTrans(gid)[this->cell()] += dm*YMix[idL]*YLiquid_[i];
            }
 
            // No mapping between solid components and carrier phase
            /*
            forAll(YSolid_, i)
            {
                label gid = composition.localToCarrierId(idS, i);
                cloud.rhoTrans(gid)[this->cell()] += dm*YMix[idS]*YSolid_[i];
            }
            */
 
            cloud.UTransRef()[this->cell()] += dm*U0;
 
            cloud.hsTransRef()[this->cell()] +=
                dm*hsEff(cloud, td, pc, T0, idG, idL, idS);
 
            cloud.phaseChange().addToPhaseChangeMass(np0*mass1);
        }
 
        return;
    }
 
    // Correct surface values due to emitted species
    this->correctSurfaceValues(cloud, td, Ts, Cs, rhos, mus, Prs, kappas);
    Res = this->Re(rhos, U0, td.Uc(), this->d_, mus);
 
 
    // 3. Compute heat- and momentum transfers
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
    // Heat transfer
    // ~~~~~~~~~~~~~
 
    // Calculate new particle temperature
    this->T_ =
        this->calcHeatTransfer
        (
            cloud,
            td,
            dt,
            Res,
            Prs,
            kappas,
            NCpW,
            Sh,
            dhsTrans,
            Sph
        );
 
 
    this->Cp_ = CpEff(cloud, td, pc, this->T_, idG, idL, idS);
 
 
    // Motion
    // ~~~~~~
 
    // Calculate new particle velocity
    this->U_ =
        this->calcVelocity(cloud, td, dt, Res, mus, mass1, Su, dUTrans, Spu);
 
 
    // 4. Accumulate carrier phase source terms
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
    if (cloud.solution().coupled())
    {
        // Transfer mass lost to carrier mass, momentum and enthalpy sources
        forAll(YGas_, i)
        {
            scalar dm = np0*dMassGas[i];
            label gid = composition.localToCarrierId(idG, i);
            scalar hs = composition.carrier().hsi(gid, pc, T0);
            cloud.rhoTrans(gid)[this->cell()] += dm;
            cloud.UTransRef()[this->cell()] += dm*U0;
            cloud.hsTransRef()[this->cell()] += dm*hs;
        }
        forAll(YLiquid_, i)
        {
            scalar dm = np0*dMassLiquid[i];
            label gid = composition.localToCarrierId(idL, i);
            scalar hs = composition.carrier().hsi(gid, pc, T0);
            cloud.rhoTrans(gid)[this->cell()] += dm;
            cloud.UTransRef()[this->cell()] += dm*U0;
            cloud.hsTransRef()[this->cell()] += dm*hs;
        }
 
        // No mapping between solid components and carrier phase
        /*
        forAll(YSolid_, i)
        {
            scalar dm = np0*dMassSolid[i];
            label gid = composition.localToCarrierId(idS, i);
            scalar hs = composition.carrier().hsi(gid, pc, T0);
            cloud.rhoTrans(gid)[this->cell()] += dm;
            cloud.UTransRef()[this->cell()] += dm*U0;
            cloud.hsTransRef()[this->cell()] += dm*hs;
        }
        */
 
        forAll(dMassSRCarrier, i)
        {
            scalar dm = np0*dMassSRCarrier[i];
            scalar hs = composition.carrier().hsi(i, pc, T0);
            cloud.rhoTrans(i)[this->cell()] += dm;
            cloud.UTransRef()[this->cell()] += dm*U0;
            cloud.hsTransRef()[this->cell()] += dm*hs;
        }
 
        // Update momentum transfer
        cloud.UTransRef()[this->cell()] += np0*dUTrans;
        cloud.UCoeffRef()[this->cell()] += np0*Spu;
 
        // Update sensible enthalpy transfer
        cloud.hsTransRef()[this->cell()] += np0*dhsTrans;
        cloud.hsCoeffRef()[this->cell()] += np0*Sph;
 
        // Update radiation fields
        if (cloud.radiation())
        {
            const scalar ap = this->areaP();
            const scalar T4 = pow4(T0);
            cloud.radAreaP()[this->cell()] += dt*np0*ap;
            cloud.radT4()[this->cell()] += dt*np0*T4;
            cloud.radAreaPT4()[this->cell()] += dt*np0*ap*T4;
        }
    }
}
 
 
// * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
 
template<class ParcelType>
template<class TrackCloudType>
void Foam::ReactingMultiphaseParcel<ParcelType>::calcDevolatilisation
(
    TrackCloudType& cloud,
    trackingData& td,
    const scalar dt,
    const scalar Ts,
    const scalar d,
    const scalar T,
    const scalar mass,
    const scalar mass0,
    const scalarField& YGasEff,
    const scalarField& YLiquidEff,
    const scalarField& YSolidEff,
    label& canCombust,
    scalarField& dMassDV,
    scalar& Sh,
    scalar& N,
    scalar& NCpW,
    scalarField& Cs
) const
{
    // Check that model is active
    if
    (
        isType
        <
            NoDevolatilisation
            <
                typename TrackCloudType::reactingMultiphaseCloudType
            >
        >
        (
            cloud.devolatilisation()
        )
    )
    {
        if (canCombust != -1)
        {
            canCombust = 1;
        }
        return;
    }
 
    // Initialise demand-driven constants
    (void)cloud.constProps().TDevol();
    (void)cloud.constProps().LDevol();
 
    // Check that the parcel temperature is within necessary limits for
    // devolatilisation to occur
    if (T < cloud.constProps().TDevol() || canCombust == -1)
    {
        return;
    }
 
    typedef typename TrackCloudType::thermoCloudType thermoCloudType;
    const CompositionModel<thermoCloudType>& composition =
        cloud.composition();
 
    const label idG = composition.idGas();
 
    const typename TrackCloudType::parcelType& p =
        static_cast<const typename TrackCloudType::parcelType&>(*this);
    typename TrackCloudType::parcelType::trackingData& ttd =
        static_cast<typename TrackCloudType::parcelType::trackingData&>(td);
 
    // Total mass of volatiles evolved
    cloud.devolatilisation().calculate
    (
        p,
        ttd,
        dt,
        mass0,
        mass,
        T,
        YGasEff,
        YLiquidEff,
        YSolidEff,
        canCombust,
        dMassDV
    );
 
    scalar dMassTot = sum(dMassDV);
 
    cloud.devolatilisation().addToDevolatilisationMass
    (
        this->nParticle_*dMassTot
    );
 
    Sh -= dMassTot*cloud.constProps().LDevol()/dt;
 
    // Update molar emissions
    if (cloud.heatTransfer().BirdCorrection())
    {
        // Molar average molecular weight of carrier mix
        const scalar Wc = max(small, td.rhoc()*RR*td.Tc()/td.pc());
 
        // Note: hardcoded gaseous diffusivities for now
        // TODO: add to carrier thermo
        const scalar beta = sqr(cbrt(15.0) + cbrt(15.0));
 
        forAll(dMassDV, i)
        {
            const label id = composition.localToCarrierId(idG, i);
            const scalar Cp = composition.carrier().Cpi(id, td.pc(), Ts);
            const scalar W = composition.carrier().WiValue(id);
            const scalar Ni = dMassDV[i]/(this->areaS(d)*dt*W);
 
            // Dab calc'd using API vapour mass diffusivity function
            const scalar Dab =
                3.6059e-3*(pow(1.8*Ts, 1.75))
               *sqrt(1.0/W + 1.0/Wc)
               /(td.pc()*beta);
 
            N += Ni;
            NCpW += Ni*Cp*W;
            Cs[id] += Ni*d/(2.0*Dab);
        }
    }
}
 
 
template<class ParcelType>
template<class TrackCloudType>
void Foam::ReactingMultiphaseParcel<ParcelType>::calcSurfaceReactions
(
    TrackCloudType& cloud,
    trackingData& td,
    const scalar dt,
    const scalar d,
    const scalar T,
    const scalar mass,
    const label canCombust,
    const scalar N,
    const scalarField& YMix,
    const scalarField& YGas,
    const scalarField& YLiquid,
    const scalarField& YSolid,
    scalarField& dMassSRGas,
    scalarField& dMassSRLiquid,
    scalarField& dMassSRSolid,
    scalarField& dMassSRCarrier,
    scalar& Sh,
    scalar& dhsTrans
) const
{
    // Check that model is active
    if
    (
        isType
        <
            NoSurfaceReaction
            <
                typename TrackCloudType::reactingMultiphaseCloudType
            >
        >
        (
            cloud.surfaceReaction()
        )
    )
    {
        return;
    }
 
    // Initialise demand-driven constants
    (void)cloud.constProps().hRetentionCoeff();
    (void)cloud.constProps().TMax();
 
    // Check that model is active
    if (canCombust != 1)
    {
        return;
    }
 
 
    // Update surface reactions
    const scalar hReaction = cloud.surfaceReaction().calculate
    (
        dt,
        this->cell(),
        d,
        T,
        td.Tc(),
        td.pc(),
        td.rhoc(),
        mass,
        YGas,
        YLiquid,
        YSolid,
        YMix,
        N,
        dMassSRGas,
        dMassSRLiquid,
        dMassSRSolid,
        dMassSRCarrier
    );
 
    cloud.surfaceReaction().addToSurfaceReactionMass
    (
        this->nParticle_
       *(sum(dMassSRGas) + sum(dMassSRLiquid) + sum(dMassSRSolid))
    );
 
    const scalar xsi = min(T/cloud.constProps().TMax(), 1.0);
    const scalar coeff =
        (1.0 - xsi*xsi)*cloud.constProps().hRetentionCoeff();
 
    Sh += coeff*hReaction/dt;
 
    dhsTrans += (1.0 - coeff)*hReaction;
}
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
template<class ParcelType>
Foam::ReactingMultiphaseParcel<ParcelType>::ReactingMultiphaseParcel
(
    const ReactingMultiphaseParcel<ParcelType>& p
)
:
    ParcelType(p),
    mass0_(p.mass0_),
    YGas_(p.YGas_),
    YLiquid_(p.YLiquid_),
    YSolid_(p.YSolid_),
    canCombust_(p.canCombust_)
{}
 
 
// * * * * * * * * * * * * * * IOStream operators  * * * * * * * * * * * * * //
 
#include "ReactingMultiphaseParcelIO.C"
 
// ************************************************************************* //