COxidationKineticDiffusionLimitedRate.C

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#include "COxidationKineticDiffusionLimitedRate.H"
#include "mathematicalConstants.H"
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
template<class CloudType>
Foam::COxidationKineticDiffusionLimitedRate<CloudType>::
COxidationKineticDiffusionLimitedRate
(
    const dictionary& dict,
    CloudType& owner
)
:
    SurfaceReactionModel<CloudType>(dict, owner, typeName),
    Sb_(this->coeffDict().getScalar("Sb")),
    C1_(this->coeffDict().getScalar("C1")),
    C2_(this->coeffDict().getScalar("C2")),
    E_(this->coeffDict().getScalar("E")),
    CsLocalId_(-1),
    O2GlobalId_(owner.composition().carrierId("O2")),
    CO2GlobalId_(owner.composition().carrierId("CO2")),
    WC_(0.0),
    WO2_(0.0),
    HcCO2_(0.0)
{
    // Determine Cs ids
    label idSolid = owner.composition().idSolid();
    CsLocalId_ = owner.composition().localId(idSolid, "C");
 
    // Set local copies of thermo properties
    WO2_ = owner.thermo().carrier().W(O2GlobalId_);
    const scalar WCO2 = owner.thermo().carrier().W(CO2GlobalId_);
    WC_ = WCO2 - WO2_;
 
    HcCO2_ = owner.thermo().carrier().Hc(CO2GlobalId_);
 
    const scalar YCloc = owner.composition().Y0(idSolid)[CsLocalId_];
    const scalar YSolidTot = owner.composition().YMixture0()[idSolid];
    Info<< "    C(s): particle mass fraction = " << YCloc*YSolidTot << endl;
}
 
 
template<class CloudType>
Foam::COxidationKineticDiffusionLimitedRate<CloudType>::
COxidationKineticDiffusionLimitedRate
(
    const COxidationKineticDiffusionLimitedRate<CloudType>& srm
)
:
    SurfaceReactionModel<CloudType>(srm),
    Sb_(srm.Sb_),
    C1_(srm.C1_),
    C2_(srm.C2_),
    E_(srm.E_),
    CsLocalId_(srm.CsLocalId_),
    O2GlobalId_(srm.O2GlobalId_),
    CO2GlobalId_(srm.CO2GlobalId_),
    WC_(srm.WC_),
    WO2_(srm.WO2_),
    HcCO2_(srm.HcCO2_)
{}
 
 
// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
template<class CloudType>
Foam::scalar Foam::COxidationKineticDiffusionLimitedRate<CloudType>::calculate
(
    const scalar dt,
    const scalar Re,
    const scalar nu,
    const label celli,
    const scalar d,
    const scalar T,
    const scalar Tc,
    const scalar pc,
    const scalar rhoc,
    const scalar mass,
    const scalarField& YGas,
    const scalarField& YLiquid,
    const scalarField& YSolid,
    const scalarField& YMixture,
    const scalar N,
    scalarField& dMassGas,
    scalarField& dMassLiquid,
    scalarField& dMassSolid,
    scalarField& dMassSRCarrier
) const
{
    // Fraction of remaining combustible material
    const label idSolid = CloudType::parcelType::SLD;
    const scalar fComb = YMixture[idSolid]*YSolid[CsLocalId_];
 
    // Surface combustion active combustible fraction is consumed
    if (fComb < SMALL)
    {
        return 0.0;
    }
 
    const SLGThermo& thermo = this->owner().thermo();
 
    // Local mass fraction of O2 in the carrier phase
    const scalar YO2 = thermo.carrier().Y(O2GlobalId_)[celli];
 
    // Diffusion rate coefficient
    const scalar D0 = C1_/d*pow(0.5*(T + Tc), 0.75);
 
    // Kinetic rate
    const scalar Rk = C2_*exp(-E_/(RR*Tc));
 
    // Particle surface area
    const scalar Ap = constant::mathematical::pi*sqr(d);
 
    // Change in C mass [kg]
    scalar dmC = Ap*rhoc*RR*Tc*YO2/WO2_*D0*Rk/(D0 + Rk)*dt;
 
    // Limit mass transfer by availability of C
    dmC = min(mass*fComb, dmC);
 
    // Molar consumption
    const scalar dOmega = dmC/WC_;
 
    // Change in O2 mass [kg]
    const scalar dmO2 = dOmega*Sb_*WO2_;
 
    // Mass of newly created CO2 [kg]
    const scalar dmCO2 = dOmega*(WC_ + Sb_*WO2_);
 
    // Update local particle C mass
    dMassSolid[CsLocalId_] += dOmega*WC_;
 
    // Update carrier O2 and CO2 mass
    dMassSRCarrier[O2GlobalId_] -= dmO2;
    dMassSRCarrier[CO2GlobalId_] += dmCO2;
 
    const scalar HsC = thermo.solids().properties()[CsLocalId_].Hs(T);
 
    // carrier sensible enthalpy exchange handled via change in mass
 
    // Heat of reaction [J]
    return dmC*HsC - dmCO2*HcCO2_;
}
 
 
// ************************************************************************* //