void DiFeliceDrag::setForce() const { if (scaleDia_ > 1) Info << typeName << " using scale = " << scaleDia_ << endl; else if (particleCloud_.cg() > 1){ scaleDia_=particleCloud_.cg(); Info << typeName << " using scale from liggghts cg = " << scaleDia_ << endl; } const volScalarField& nufField = forceSubM(0).nuField(); const volScalarField& rhoField = forceSubM(0).rhoField(); vector position(0,0,0); scalar voidfraction(1); vector Ufluid(0,0,0); vector drag(0,0,0); vector dragExplicit(0,0,0); scalar dragCoefficient(0); label cellI=0; vector Us(0,0,0); vector Ur(0,0,0); scalar ds(0); scalar nuf(0); scalar rho(0); scalar magUr(0); scalar Rep(0); scalar Cd(0); interpolationCellPoint<scalar> voidfractionInterpolator_(voidfraction_); interpolationCellPoint<vector> UInterpolator_(U_); #include "setupProbeModel.H" for(int index = 0;index < particleCloud_.numberOfParticles(); index++) { cellI = particleCloud_.cellIDs()[index][0]; drag = vector(0,0,0); dragExplicit = vector(0,0,0); Ufluid =vector(0,0,0); if (cellI > -1) // particle Found { if(forceSubM(0).interpolation()) { position = particleCloud_.position(index); voidfraction = voidfractionInterpolator_.interpolate(position,cellI); Ufluid = UInterpolator_.interpolate(position,cellI); }else { voidfraction = voidfraction_[cellI]; Ufluid = U_[cellI]; } Us = particleCloud_.velocity(index); Ur = Ufluid-Us; ds = 2*particleCloud_.radius(index); nuf = nufField[cellI]; rho = rhoField[cellI]; magUr = mag(Ur); Rep = 0; Cd = 0; dragCoefficient = 0; if (magUr > 0) { // calc particle Re Nr Rep = ds/scaleDia_*voidfraction*magUr/(nuf+SMALL); // calc fluid drag Coeff Cd = sqr(0.63 + 4.8/sqrt(Rep)); // calc model coefficient Xi scalar Xi = 3.7 - 0.65 * exp(-sqr(1.5-log10(Rep))/2); // calc particle's drag dragCoefficient = 0.125*Cd*rho *M_PI *ds*ds *scaleDia_ *pow(voidfraction,(2-Xi))*magUr *scaleDrag_; if (modelType_=="B") dragCoefficient /= voidfraction; drag = dragCoefficient*Ur; //total drag force! forceSubM(0).explicitCorr(drag,dragExplicit,dragCoefficient,Ufluid,U_[cellI],Us,UsField_[cellI],forceSubM(0).verbose(),index); } if(forceSubM(0).verbose() && index >-1 && index <102) { Pout << "index = " << index << endl; Pout << "scaleDrag_ = " << scaleDrag_ << endl; Pout << "Us = " << Us << endl; Pout << "Ur = " << Ur << endl; Pout << "ds/scale = " << ds/scaleDia_ << endl; Pout << "rho = " << rho << endl; Pout << "nuf = " << nuf << endl; Pout << "voidfraction = " << voidfraction << endl; Pout << "Rep = " << Rep << endl; Pout << "Cd = " << Cd << endl; Pout << "drag (total) = " << drag << endl; } //Set value fields and write the probe if(probeIt_) { #include "setupProbeModelfields.H" vValues.append(drag); //first entry must the be the force vValues.append(Ur); sValues.append(Rep); sValues.append(Cd); sValues.append(voidfraction); particleCloud_.probeM().writeProbe(index, sValues, vValues); } } // write particle based data to global array forceSubM(0).partToArray(index,drag,dragExplicit,Ufluid,dragCoefficient); } }
void virtualMassForce::setForce() const { reAllocArrays(); scalar dt = U_.mesh().time().deltaT().value(); vector position(0,0,0); vector Ufluid(0,0,0); vector Ur(0,0,0); vector DDtU(0,0,0); //Compute extra vfields in case it is needed volVectorField DDtU_(0.0*U_/U_.mesh().time().deltaT()); if(splitUrelCalculation_) DDtU_ = fvc::ddt(U_) + fvc::div(phi_, U_); //Total Derivative of fluid velocity interpolationCellPoint<vector> UInterpolator_( U_); interpolationCellPoint<vector> DDtUInterpolator_(DDtU_); #include "setupProbeModel.H" bool haveUrelOld_(false); for(int index = 0; index < particleCloud_.numberOfParticles(); index++) { vector virtualMassForce(0,0,0); label cellI = particleCloud_.cellIDs()[index][0]; if (cellI > -1) // particle Found { if(forceSubM(0).interpolation()) { position = particleCloud_.position(index); Ufluid = UInterpolator_.interpolate(position,cellI); } else { Ufluid = U_[cellI]; } if(splitUrelCalculation_) //if split, just use total derivative of fluid velocity if(forceSubM(0).interpolation()) { DDtU = DDtUInterpolator_.interpolate(position,cellI); } else { DDtU = DDtU_[cellI]; } else { vector Us = particleCloud_.velocity(index); Ur = Ufluid - Us; } //Check of particle was on this CPU the last step if(UrelOld_[index][0]==NOTONCPU) //use 1. element to indicate that particle was on this CPU the last time step haveUrelOld_ = false; else haveUrelOld_ = true; vector UrelOld(0.,0.,0.); vector ddtUrel(0.,0.,0.); for(int j=0; j<3; j++) { UrelOld[j] = UrelOld_[index][j]; UrelOld_[index][j] = Ur[j]; } if(haveUrelOld_ ) //only compute force if we have old (relative) velocity ddtUrel = (Ur-UrelOld)/dt; if(splitUrelCalculation_) //we can always compute the total derivative in case we split ddtUrel = DDtU; scalar ds = 2*particleCloud_.radius(index); scalar Vs = ds*ds*ds*M_PI/6; scalar rho = forceSubM(0).rhoField()[cellI]; virtualMassForce = Cadd_ * rho * Vs * ddtUrel; if( forceSubM(0).verbose() ) //&& index>100 && index < 105) { Pout << "index / cellI = " << index << tab << cellI << endl; Pout << "position = " << particleCloud_.position(index) << endl; } //Set value fields and write the probe if(probeIt_) { #include "setupProbeModelfields.H" vValues.append(virtualMassForce); //first entry must the be the force vValues.append(Ur); vValues.append(UrelOld); vValues.append(ddtUrel); sValues.append(Vs); sValues.append(rho); particleCloud_.probeM().writeProbe(index, sValues, vValues); } } else //particle not on this CPU UrelOld_[index][0]=NOTONCPU; // write particle based data to global array forceSubM(0).partToArray(index,virtualMassForce,vector::zero); } }
void BeetstraDrag::setForce() const { scale_=cg(); Info << "BeetstraDrag using scale from liggghts cg = " << scale_ << endl; // get viscosity field #ifdef comp const volScalarField nufField = particleCloud_.turbulence().mu()/rho_; #else const volScalarField& nufField = particleCloud_.turbulence().nu(); #endif vector position(0,0,0); scalar voidfraction(1); vector Ufluid(0,0,0); vector drag(0,0,0); label cellI=0; scalar beta(0); vector Us(0,0,0); vector Ur(0,0,0); scalar ds(0); scalar nuf(0); scalar rho(0); scalar magUr(0); scalar Rep(0); scalar Vs(0); scalar localPhiP(0); scalar filterDragPrefactor(1.0); scalar cCorrParcelSize_(1.0) ; scalar vCell(0); scalar FfFilterPrime(1); scalar F0=0.; scalar G0=0.; interpolationCellPoint<scalar> voidfractionInterpolator_(voidfraction_); interpolationCellPoint<vector> UInterpolator_(U_); #include "setupProbeModel.H" for(int index = 0;index < particleCloud_.numberOfParticles(); index++) { //if(mask[index][0]) //{ cellI = particleCloud_.cellIDs()[index][0]; drag = vector(0,0,0); Ufluid= vector(0,0,0); if (cellI > -1) // particle Found { if(interpolation_) { position = particleCloud_.position(index); voidfraction = voidfractionInterpolator_.interpolate(position,cellI); Ufluid = UInterpolator_.interpolate(position,cellI); //Ensure interpolated void fraction to be meaningful // Info << " --> voidfraction: " << voidfraction << endl; if(voidfraction>1.00) voidfraction = 1.00; if(voidfraction<0.10) voidfraction = 0.10; } else { voidfraction = voidfraction_[cellI]; Ufluid = U_[cellI]; } Us = particleCloud_.velocity(index); Ur = Ufluid-Us; ds = 2*particleCloud_.radius(index); dPrim_ = ds/scale_; nuf = nufField[cellI]; rho = rho_[cellI]; magUr = mag(Ur); Rep = 0; Vs = ds*ds*ds*M_PI/6; localPhiP = 1-voidfraction+SMALL; vCell = U_.mesh().V()[cellI]; if (magUr > 0) { // calc particle Re Nr Rep = dPrim_*voidfraction*magUr/(nuf+SMALL); // 3 - C - 1 - In this section we could insert parameters // or functions // that come from a database // calc model coefficient F0 F0 = 10.f * localPhiP / voidfraction / voidfraction + voidfraction * voidfraction * ( 1.0+1.5*sqrt(localPhiP) ); // calc model coefficient G0 G0 = 0.01720833 * Rep / voidfraction / voidfraction //0.0172083 = 0.413/24 * ( 1.0 / voidfraction + 3.0 * localPhiP * voidfraction + 8.4 * powf(Rep,-0.343) ) / ( 1.0 + powf( 10., 3.0* localPhiP ) * powf( Rep,-(1.0+4.0*localPhiP)/2.0 ) ); // calc model coefficient beta beta = 18.*nuf*rho/(dPrim_*dPrim_) *voidfraction *(F0 + G0); //Apply filtered drag correction if(useFilteredDragModel_) { FfFilterPrime = FfFilterFunc( filtDragParamsLChar2_, vCell, 0 ); filterDragPrefactor = 1 - fFuncFilteredDrag(FfFilterPrime, localPhiP) * hFuncFilteredDrag(localPhiP); beta *= filterDragPrefactor; } if(useParcelSizeDependentFilteredDrag_) //Apply filtered drag correction { scalar dParceldPrim = scale_; cCorrParcelSize_ = cCorrFunctionFilteredDrag( filtDragParamsK_, filtDragParamsALimit_, filtDragParamsAExponent_, localPhiP, dParceldPrim ); beta *= cCorrParcelSize_; } // calc particle's drag drag = Vs * beta * Ur; if (modelType_=="B") drag /= voidfraction; } // 3 - C - 2 - This is a standardized debug and report section if( verbose_ ) //&& index>100 && index < 105) { Info << "index / cellI = " << index << tab << cellI << endl; Info << "position = " << particleCloud_.position(index) << endl; Info << "Us = " << Us << endl; Info << "Ur = " << Ur << endl; Info << "ds = " << ds << endl; Info << "rho = " << rho << endl; Info << "nuf = " << nuf << endl; Info << "voidfraction = " << voidfraction << endl; Info << "voidfraction_[cellI]: " << voidfraction_[cellI] << endl; Info << "Rep = " << Rep << endl; Info << "filterDragPrefactor = " << filterDragPrefactor << endl; Info << "fFuncFilteredDrag: " << fFuncFilteredDrag(FfFilterPrime, localPhiP) << endl; Info << "hFuncFilteredDrag: " << hFuncFilteredDrag(localPhiP) << endl; Info << "cCorrParcelSize: " << cCorrParcelSize_ << endl; Info << "F0 / G0: " << F0 << tab << G0 << endl; Info << "beta: " << beta << endl; Info << "drag = " << drag << endl; Info << "\nBeetstra drag model settings: treatExplicit " << treatExplicit_ << tab << "verbose: " << verbose_ << tab << "dPrim: " << dPrim_ << tab << "interpolation: " << interpolation_ << tab << "filteredDragM: " << useFilteredDragModel_ << tab << "parcelSizeDepDrag: " << useParcelSizeDependentFilteredDrag_ << endl << endl; } //Set value fields and write the probe if(probeIt_) { #include "setupProbeModelfields.H" vValues.append(drag); //first entry must the be the force vValues.append(Ur); sValues.append(Rep); sValues.append(beta); sValues.append(voidfraction); sValues.append(filterDragPrefactor); particleCloud_.probeM().writeProbe(index, sValues, vValues); } } // set force on particle if(treatExplicit_) for(int j=0;j<3;j++) expForces()[index][j] += drag[j]; else for(int j=0;j<3;j++) impForces()[index][j] += drag[j]; // set Cd if(implDEM_) { for(int j=0;j<3;j++) fluidVel()[index][j]=Ufluid[j]; if (modelType_=="B") Cds()[index][0] = Vs*beta/voidfraction; else Cds()[index][0] = Vs*beta; }else{ for(int j=0;j<3;j++) DEMForces()[index][j] += drag[j]; } //} } }
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // void scalarGeneralExchange::manipulateScalarField(volScalarField& explicitEulerSource, volScalarField& implicitEulerSource, int speciesID) const { // reset Scalar field explicitEulerSource.internalField() = 0.0; implicitEulerSource.internalField() = 0.0; if(speciesID>=0 && particleSpeciesValue_[speciesID]<0.0) //skip if species is not active return; //Set the names of the exchange fields word fieldName; word partDatName; word partFluxName; word partTransCoeffName; word partFluidName; scalar transportParameter; // realloc the arrays to pull particle data if(speciesID<0) //this is the temperature - always pull from LIGGGHTS { fieldName = tempFieldName_; partDatName = partTempName_; partFluxName = partHeatFluxName_; partTransCoeffName = partHeatTransCoeffName_; partFluidName = partHeatFluidName_; transportParameter = lambda_; allocateMyArrays(0.0); particleCloud_.dataExchangeM().getData(partDatName,"scalar-atom", partDat_); } else { fieldName = eulerianFieldNames_[speciesID]; partDatName = partSpeciesNames_[speciesID]; partFluxName = partSpeciesFluxNames_[speciesID]; partTransCoeffName = partSpeciesTransCoeffNames_[speciesID]; partFluidName = partSpeciesFluidNames_[speciesID]; transportParameter = DMolecular_[speciesID]; allocateMyArrays(0.0); if(particleSpeciesValue_[speciesID]>ALARGECONCENTRATION) particleCloud_.dataExchangeM().getData(partDatName,"scalar-atom", partDat_); } if (scaleDia_ > 1) Info << typeName << " using scale = " << scaleDia_ << endl; else if (particleCloud_.cg() > 1) { scaleDia_=particleCloud_.cg(); Info << typeName << " using scale from liggghts cg = " << scaleDia_ << endl; } //============================== // get references const volScalarField& voidfraction_(particleCloud_.mesh().lookupObject<volScalarField> (voidfractionFieldName_)); // ref to voidfraction field const volVectorField& U_(particleCloud_.mesh().lookupObject<volVectorField> (velFieldName_)); const volScalarField& fluidScalarField_(particleCloud_.mesh().lookupObject<volScalarField> (fieldName)); // ref to scalar field const volScalarField& nufField = forceSubM(0).nuField(); //============================== // calc La based heat flux vector position(0,0,0); scalar voidfraction(1); vector Ufluid(0,0,0); scalar fluidValue(0); label cellI=0; vector Us(0,0,0); vector Ur(0,0,0); scalar dscaled(0); scalar nuf(0); scalar magUr(0); scalar As(0); scalar Rep(0); scalar Pr(0); scalar sDth(scaleDia_*scaleDia_*scaleDia_); interpolationCellPoint<scalar> voidfractionInterpolator_(voidfraction_); interpolationCellPoint<vector> UInterpolator_(U_); interpolationCellPoint<scalar> fluidScalarFieldInterpolator_(fluidScalarField_); #include "setupProbeModel.H" for(int index = 0;index < particleCloud_.numberOfParticles(); ++index) { cellI = particleCloud_.cellIDs()[index][0]; if(cellI >= 0) { if(forceSubM(0).interpolation()) { position = particleCloud_.position(index); voidfraction = voidfractionInterpolator_.interpolate(position,cellI); Ufluid = UInterpolator_.interpolate(position,cellI); fluidValue = fluidScalarFieldInterpolator_.interpolate(position,cellI); }else { voidfraction = voidfraction_[cellI]; Ufluid = U_[cellI]; fluidValue = fluidScalarField_[cellI]; } // calc relative velocity Us = particleCloud_.velocity(index); Ur = Ufluid-Us; magUr = mag(Ur); dscaled = 2*particleCloud_.radius(index)/scaleDia_; As = dscaled*dscaled*M_PI*sDth; nuf = nufField[cellI]; Rep = dscaled*magUr/nuf; if(speciesID<0) //have temperature Pr = Prandtl_; else Pr = max(SMALL,nuf/transportParameter); //This is Sc for species scalar alpha = transportParameter*(this->*Nusselt)(Rep,Pr,voidfraction)/(dscaled); // calc convective heat flux [W] scalar areaTimesTransferCoefficient = alpha * As; scalar tmpPartFlux = areaTimesTransferCoefficient * (fluidValue - partDat_[index][0]); partDatFlux_[index][0] = tmpPartFlux; // split implicit/explicit contribution forceSubM(0).explicitCorrScalar( partDatTmpImpl_[index][0], partDatTmpExpl_[index][0], areaTimesTransferCoefficient, fluidValue, fluidScalarField_[cellI], partDat_[index][0], forceSubM(0).verbose() ); if(validPartTransCoeff_) partDatTransCoeff_[index][0] = alpha; if(validPartFluid_) partDatFluid_[index][0] = fluidValue; if( forceSubM(0).verbose()) { Pout << "fieldName = " << fieldName << endl; Pout << "partTransCoeffName = " << partTransCoeffName << endl; Pout << "index = " <<index << endl; Pout << "partFlux = " << tmpPartFlux << endl; Pout << "magUr = " << magUr << endl; Pout << "As = " << As << endl; Pout << "r = " << particleCloud_.radius(index) << endl; Pout << "dscaled = " << dscaled << endl; Pout << "nuf = " << nuf << endl; Pout << "Rep = " << Rep << endl; Pout << "Pr/Sc = " << Pr << endl; Pout << "Nup/Shp = " << (this->*Nusselt)(Rep,Pr,voidfraction) << endl; Pout << "partDatTransCoeff: " << partDatTransCoeff_[index][0] << endl; Pout << "voidfraction = " << voidfraction << endl; Pout << "partDat_[index][0] = " << partDat_[index][0] << endl ; Pout << "fluidValue = " << fluidValue << endl ; } //Set value fields and write the probe if(probeIt_) { #include "setupProbeModelfields.H" vValues.append(Ur); sValues.append((this->*Nusselt)(Rep,Pr,voidfraction)); sValues.append(Rep); particleCloud_.probeM().writeProbe(index, sValues, vValues); } } } //Handle explicit and implicit source terms on the Euler side //these are simple summations! particleCloud_.averagingM().setScalarSum ( explicitEulerSource, partDatTmpExpl_, particleCloud_.particleWeights(), NULL ); particleCloud_.averagingM().setScalarSum ( implicitEulerSource, partDatTmpImpl_, particleCloud_.particleWeights(), NULL ); // scale with the cell volume to get (total) volume-specific source explicitEulerSource.internalField() /= -explicitEulerSource.mesh().V(); implicitEulerSource.internalField() /= -implicitEulerSource.mesh().V(); // limit explicit source term scalar explicitEulerSourceInCell; forAll(explicitEulerSource,cellI) { explicitEulerSourceInCell = explicitEulerSource[cellI]; if(mag(explicitEulerSourceInCell) > maxSource_ ) { explicitEulerSource[cellI] = sign(explicitEulerSourceInCell) * maxSource_; } }
void GidaspowDrag::setForce() const { if (scaleDia_ > 1) Info << "Gidaspow using scale = " << scaleDia_ << endl; else if (particleCloud_.cg() > 1){ scaleDia_=particleCloud_.cg(); Info << "Gidaspow using scale from liggghts cg = " << scaleDia_ << endl; } // get viscosity field #ifdef comp const volScalarField nufField = particleCloud_.turbulence().mu() / rho_; #else const volScalarField& nufField = particleCloud_.turbulence().nu(); #endif vector position(0,0,0); scalar voidfraction(1); vector Ufluid(0,0,0); vector drag(0,0,0); label cellI=0; vector Us(0,0,0); vector Uturb(0,0,0); vector Ur(0,0,0); scalar ds(0); scalar nuf(0); scalar rho(0); scalar magUr(0); scalar Rep(0); scalar Vs(0); scalar localPhiP(0); scalar CdMagUrLag(0); //Cd of the very particle scalar KslLag(0); //momentum exchange of the very particle (per unit volume) scalar betaP(0); //momentum exchange of the very particle interpolationCellPoint<scalar> voidfractionInterpolator_(voidfraction_); interpolationCellPoint<vector> UInterpolator_(U_); #include "setupProbeModel.H" for(int index = 0;index < particleCloud_.numberOfParticles(); ++index) { //if(mask[index][0]) //{ cellI = particleCloud_.cellIDs()[index][0]; drag = vector(0,0,0); betaP = 0; Vs = 0; Ufluid =vector(0,0,0); voidfraction=0; if (cellI > -1) // particle Found { position = particleCloud_.position(index); if(interpolation_) { //position = particleCloud_.position(index); voidfraction = voidfractionInterpolator_.interpolate(position,cellI); Ufluid = UInterpolator_.interpolate(position,cellI); //Ensure interpolated void fraction to be meaningful // Info << " --> voidfraction: " << voidfraction << endl; if(voidfraction>1.00) voidfraction = 1.0; if(voidfraction<0.10) voidfraction = 0.10; } else { voidfraction = voidfraction_[cellI]; Ufluid = U_[cellI]; } Us = particleCloud_.velocity(index); Ur = Ufluid-Us; //accounting for turbulent dispersion if(particleCloud_.dispersionM().isActive()) { Uturb=particleCloud_.fluidTurbVel(index); Ur=(Ufluid+Uturb)-Us; } magUr = mag(Ur); ds = 2*particleCloud_.radius(index)*phi_; rho = rho_[cellI]; nuf = nufField[cellI]; Rep=0.0; localPhiP = 1.0f-voidfraction+SMALL; Vs = ds*ds*ds*M_PI/6; //Compute specific drag coefficient (i.e., Force per unit slip velocity and per m³ SUSPENSION) //Wen and Yu, 1966 if(voidfraction > 0.8) //dilute { Rep=ds/scaleDia_*voidfraction*magUr/nuf; CdMagUrLag = (24.0*nuf/(ds/scaleDia_*voidfraction)) //1/magUr missing here, but compensated in expression for KslLag! *(scalar(1)+0.15*Foam::pow(Rep, 0.687)); KslLag = 0.75*( rho*localPhiP*voidfraction*CdMagUrLag / (ds/scaleDia_*Foam::pow(voidfraction,2.65)) ); } //Ergun, 1952 else //dense { KslLag = (150*Foam::pow(localPhiP,2)*nuf*rho)/ (voidfraction*ds/scaleDia_*ds/scaleDia_+SMALL) + (1.75*(localPhiP) * magUr * rho)/ ((ds/scaleDia_)); } // calc particle's drag coefficient (i.e., Force per unit slip velocity and per m³ PARTICLE) betaP = KslLag / localPhiP; // calc particle's drag drag = Vs * betaP * Ur * scaleDrag_; if (modelType_=="B") drag /= voidfraction; if(verbose_ && index >=0 && index <1) { Pout << " "<< endl; Pout << "Gidaspow drag force verbose: " << endl; Pout << "magUr = " << magUr << endl; Pout << "localPhiP = " << localPhiP << endl; Pout << "CdMagUrLag = " << CdMagUrLag << endl; Pout << "treatExplicit_ = " << treatExplicit_ << endl; Pout << "implDEM_ = " << implDEM_ << endl; Pout << "modelType_ = " << modelType_ << endl; Pout << "KslLag = " << KslLag << endl; Pout << "cellI = " << cellI << endl; Pout << "index = " << index << endl; Pout << "Ufluid = " << Ufluid << endl; Pout << "Uturb = " << Uturb << endl; Pout << "Us = " << Us << endl; Pout << "Ur = " << Ur << endl; Pout << "Vs = " << Vs << endl; Pout << "ds = " << ds << endl; Pout << "ds/scale = " << ds/scaleDia_ << endl; Pout << "phi = " << phi_ << endl; Pout << "rho = " << rho << endl; Pout << "nuf = " << nuf << endl; Pout << "voidfraction = " << voidfraction << endl; Pout << "Rep = " << Rep << endl; Pout << "localPhiP = " << localPhiP << endl; Pout << "betaP = " << betaP << endl; Pout << "drag = " << drag << endl; Pout << "position = " << position << endl; Pout << " "<< endl; } //Set value fields and write the probe if(probeIt_) { #include "setupProbeModelfields.H" vValues.append(drag); //first entry must the be the force vValues.append(Ur); sValues.append(Rep); sValues.append(betaP); sValues.append(voidfraction); particleCloud_.probeM().writeProbe(index, sValues, vValues); } } // set force on particle //treatExplicit_ = false by default if(treatExplicit_) for(int j=0;j<3;j++) expForces()[index][j] += drag[j]; else for(int j=0;j<3;j++) impForces()[index][j] += drag[j]; // set Cd //implDEM_ = false by default if(implDEM_) { for(int j=0;j<3;j++) fluidVel()[index][j]=Ufluid[j]; if (modelType_=="B" && cellI > -1) Cds()[index][0] = Vs*betaP/voidfraction*scaleDrag_; else Cds()[index][0] = Vs*betaP*scaleDrag_; }else{ for(int j=0;j<3;j++) DEMForces()[index][j] += drag[j]; } //}// end if mask }// end loop particles }
void KochHillDrag::setForce ( double** const& mask, double**& impForces, double**& expForces, double**& DEMForces ) const { // get viscosity field #ifdef comp const volScalarField nufField = particleCloud_.turbulence().mu()/rho_; #else const volScalarField& nufField = particleCloud_.turbulence().nu(); #endif vector position(0,0,0); scalar voidfraction(1); vector Ufluid(0,0,0); vector drag(0,0,0); label cellI=0; vector Us(0,0,0); vector Ur(0,0,0); scalar ds(0); scalar nuf(0); scalar rho(0); scalar magUr(0); scalar Rep(0); scalar Vs(0); scalar volumefraction(0); interpolationCellPoint<scalar> voidfractionInterpolator_(voidfraction_); interpolationCellPoint<vector> UInterpolator_(U_); for(int index = 0;index < particleCloud_.numberOfParticles(); index++) { if(mask[index][0]) { cellI = particleCloud_.cellIDs()[index][0]; drag = vector(0,0,0); if (cellI > -1) // particle Found { if(interpolation_) { position = particleCloud_.position(index); voidfraction = voidfractionInterpolator_.interpolate(position,cellI); Ufluid = UInterpolator_.interpolate(position,cellI); }else { voidfraction = particleCloud_.voidfraction(index); Ufluid = U_[cellI]; } Us = particleCloud_.velocity(index); Ur = Ufluid-Us; ds = 2*particleCloud_.radius(index); nuf = nufField[cellI]; rho = rho_[cellI]; magUr = mag(Ur); Rep = 0; Vs = ds*ds*ds*M_PI/6; volumefraction = 1-voidfraction+SMALL; if (magUr > 0) { // calc particle Re Nr Rep = ds/scale_*voidfraction*magUr/(nuf+SMALL); // calc model coefficient F0 scalar F0=0.; if(volumefraction < 0.4) { F0 = (1+3*sqrt((volumefraction)/2)+135/64*volumefraction*log(volumefraction)+16.14*volumefraction)/ (1+0.681*volumefraction-8.48*sqr(volumefraction)+8.16*volumefraction*volumefraction*volumefraction); } else { F0 = 10*volumefraction/(voidfraction*voidfraction*voidfraction); } // calc model coefficient F3 scalar F3 = 0.0673+0.212*volumefraction+0.0232/pow(voidfraction,5); // calc model coefficient beta scalar beta = 18*nuf*rho*voidfraction*voidfraction*volumefraction/(ds/scale_*ds/scale_)* (F0 + 0.5*F3*Rep); // calc particle's drag drag = Vs*beta/volumefraction*Ur; if (modelType_=="B") drag /= voidfraction; } if(verbose_ && index >=0 && index <2) { Info << "index = " << index << endl; Info << "Us = " << Us << endl; Info << "Ur = " << Ur << endl; Info << "ds = " << ds << endl; Info << "ds/scale = " << ds/scale_ << endl; Info << "rho = " << rho << endl; Info << "nuf = " << nuf << endl; Info << "voidfraction = " << voidfraction << endl; Info << "Rep = " << Rep << endl; Info << "drag = " << drag << endl; } } // set force on particle if(treatExplicit_) for(int j=0;j<3;j++) expForces[index][j] += drag[j]; else for(int j=0;j<3;j++) impForces[index][j] += drag[j]; } } }
void KochHillDrag::setForce() const { const volScalarField& nufField = forceSubM(0).nuField(); const volScalarField& rhoField = forceSubM(0).rhoField(); //update force submodels to prepare for loop for (int iFSub=0;iFSub<nrForceSubModels();iFSub++) forceSubM(iFSub).preParticleLoop(forceSubM(iFSub).verbose()); vector position(0,0,0); scalar voidfraction(1); vector Ufluid(0,0,0); vector drag(0,0,0); vector dragExplicit(0,0,0); scalar dragCoefficient(0); label cellI=0; vector Us(0,0,0); vector Ur(0,0,0); scalar ds(0); scalar dParcel(0); scalar nuf(0); scalar rho(0); scalar magUr(0); scalar Rep(0); scalar Vs(0); scalar volumefraction(0); scalar betaP(0); scalar piBySix(M_PI/6); int couplingInterval(particleCloud_.dataExchangeM().couplingInterval()); #include "resetVoidfractionInterpolator.H" #include "resetUInterpolator.H" #include "setupProbeModel.H" for(int index = 0;index < particleCloud_.numberOfParticles(); index++) { cellI = particleCloud_.cellIDs()[index][0]; drag = vector(0,0,0); dragExplicit = vector(0,0,0); dragCoefficient=0; betaP = 0; Vs = 0; Ufluid =vector(0,0,0); voidfraction=0; if (cellI > -1) // particle Found { if(forceSubM(0).interpolation()) { position = particleCloud_.position(index); voidfraction = voidfractionInterpolator_().interpolate(position,cellI); Ufluid = UInterpolator_().interpolate(position,cellI); //Ensure interpolated void fraction to be meaningful // Info << " --> voidfraction: " << voidfraction << endl; if(voidfraction>1.00) voidfraction = 1.00; if(voidfraction<0.40) voidfraction = 0.40; }else { voidfraction = voidfraction_[cellI]; Ufluid = U_[cellI]; } ds = particleCloud_.d(index); dParcel = ds; forceSubM(0).scaleDia(ds); //caution: this fct will scale ds! nuf = nufField[cellI]; rho = rhoField[cellI]; Us = particleCloud_.velocity(index); //Update any scalar or vector quantity for (int iFSub=0;iFSub<nrForceSubModels();iFSub++) forceSubM(iFSub).update( index, cellI, ds, Ufluid, Us, nuf, rho, forceSubM(0).verbose() ); Ur = Ufluid-Us; magUr = mag(Ur); Rep = 0; Vs = ds*ds*ds*piBySix; volumefraction = max(SMALL,min(1-SMALL,1-voidfraction)); if (magUr > 0) { // calc particle Re Nr Rep = ds*voidfraction*magUr/(nuf+SMALL); // calc model coefficient F0 scalar F0=0.; if(volumefraction < 0.4) { F0 = (1. + 3.*sqrt((volumefraction)/2.) + (135./64.)*volumefraction*log(volumefraction) + 16.14*volumefraction )/ (1+0.681*volumefraction-8.48*sqr(volumefraction) +8.16*volumefraction*volumefraction*volumefraction ); } else { F0 = 10*volumefraction/(voidfraction*voidfraction*voidfraction); } // calc model coefficient F3 scalar F3 = 0.0673+0.212*volumefraction+0.0232/pow(voidfraction,5); //Calculate F (the factor 0.5 is introduced, since Koch and Hill, ARFM 33:619–47, use the radius //to define Rep, and we use the particle diameter, see vanBuijtenen et al., CES 66:2368–2376. scalar F = voidfraction * (F0 + 0.5*F3*Rep); // calc drag model coefficient betaP betaP = 18.*nuf*rho/(ds*ds)*voidfraction*F; // calc particle's drag dragCoefficient = Vs*betaP; if (modelType_=="B") dragCoefficient /= voidfraction; forceSubM(0).scaleCoeff(dragCoefficient,dParcel); if(forceSubM(0).switches()[7]) // implForceDEMaccumulated=true { //get drag from the particle itself for (int j=0 ; j<3 ; j++) drag[j] = particleCloud_.fAccs()[index][j]/couplingInterval; }else { drag = dragCoefficient * Ur; // explicitCorr for (int iFSub=0;iFSub<nrForceSubModels();iFSub++) forceSubM(iFSub).explicitCorr( drag, dragExplicit, dragCoefficient, Ufluid, U_[cellI], Us, UsField_[cellI], forceSubM(iFSub).verbose() ); } } if(forceSubM(0).verbose() && index >=0 && index <2) { Pout << "cellI = " << cellI << endl; Pout << "index = " << index << endl; Pout << "Us = " << Us << endl; Pout << "Ur = " << Ur << endl; Pout << "dprim = " << ds << endl; Pout << "rho = " << rho << endl; Pout << "nuf = " << nuf << endl; Pout << "voidfraction = " << voidfraction << endl; Pout << "Rep = " << Rep << endl; Pout << "betaP = " << betaP << endl; Pout << "drag = " << drag << endl; } //Set value fields and write the probe if(probeIt_) { #include "setupProbeModelfields.H" // Note: for other than ext one could use vValues.append(x) // instead of setSize vValues.setSize(vValues.size()+1, drag); //first entry must the be the force vValues.setSize(vValues.size()+1, Ur); sValues.setSize(sValues.size()+1, Rep); sValues.setSize(sValues.size()+1, betaP); sValues.setSize(sValues.size()+1, voidfraction); particleCloud_.probeM().writeProbe(index, sValues, vValues); } } // write particle based data to global array forceSubM(0).partToArray(index,drag,dragExplicit,Ufluid,dragCoefficient); } }
void DiFeliceDrag::setForce() const { if (scaleDia_ > 1) Info << "DiFeliceDrag using scale = " << scaleDia_ << endl; else if (particleCloud_.cg() > 1){ scaleDia_=particleCloud_.cg(); Info << "DiFeliceDrag using scale from liggghts cg = " << scaleDia_ << endl; } // get viscosity field #ifdef comp const volScalarField nufField = particleCloud_.turbulence().mu() / rho_; #else const volScalarField& nufField = particleCloud_.turbulence().nu(); #endif vector position(0,0,0); scalar voidfraction(1); vector Ufluid(0,0,0); vector drag(0,0,0); label cellI=0; vector Us(0,0,0); vector Ur(0,0,0); scalar ds(0); scalar nuf(0); scalar rho(0); scalar magUr(0); scalar Rep(0); scalar Cd(0); vector UfluidFluct(0,0,0); vector UsFluct(0,0,0); vector dragExplicit(0,0,0); scalar dragCoefficient(0); interpolationCellPoint<scalar> voidfractionInterpolator_(voidfraction_); interpolationCellPoint<vector> UInterpolator_(U_); #include "setupProbeModel.H" for(int index = 0;index < particleCloud_.numberOfParticles(); index++) { //if(mask[index][0]) //{ cellI = particleCloud_.cellIDs()[index][0]; drag = vector(0,0,0); if (cellI > -1) // particle Found { if(interpolation_) { position = particleCloud_.position(index); voidfraction = voidfractionInterpolator_.interpolate(position,cellI); Ufluid = UInterpolator_.interpolate(position,cellI); }else { voidfraction = voidfraction_[cellI]; Ufluid = U_[cellI]; } Us = particleCloud_.velocity(index); Ur = Ufluid-Us; ds = 2*particleCloud_.radius(index); nuf = nufField[cellI]; rho = rho_[cellI]; magUr = mag(Ur); Rep = 0; Cd = 0; dragCoefficient = 0; if (magUr > 0) { // calc particle Re Nr Rep = ds/scaleDia_*voidfraction*magUr/(nuf+SMALL); // calc fluid drag Coeff Cd = sqr(0.63 + 4.8/sqrt(Rep)); // calc model coefficient Xi scalar Xi = 3.7 - 0.65 * exp(-sqr(1.5-log10(Rep))/2); // calc particle's drag dragCoefficient = 0.125*Cd*rho *M_PI *ds*ds *scaleDia_ *pow(voidfraction,(2-Xi))*magUr *scaleDrag_; if (modelType_=="B") dragCoefficient /= voidfraction; drag = dragCoefficient*Ur; //total drag force! //Split forces if(splitImplicitExplicit_) { UfluidFluct = Ufluid - U_[cellI]; UsFluct = Us - UsField_[cellI]; dragExplicit = dragCoefficient*(UfluidFluct - UsFluct); //explicit part of force } } if(verbose_ && index >-1 && index <102) { Pout << "index = " << index << endl; Pout << "Us = " << Us << endl; Pout << "Ur = " << Ur << endl; Pout << "ds/scale = " << ds/scaleDia_ << endl; Pout << "rho = " << rho << endl; Pout << "nuf = " << nuf << endl; Pout << "voidfraction = " << voidfraction << endl; Pout << "Rep = " << Rep << endl; Pout << "Cd = " << Cd << endl; Pout << "drag (total) = " << drag << endl; if(splitImplicitExplicit_) { Pout << "UfluidFluct = " << UfluidFluct << endl; Pout << "UsFluct = " << UsFluct << endl; Pout << "dragExplicit = " << dragExplicit << endl; } } //Set value fields and write the probe if(probeIt_) { #include "setupProbeModelfields.H" vValues.append(drag); //first entry must the be the force vValues.append(Ur); sValues.append(Rep); sValues.append(Cd); sValues.append(voidfraction); particleCloud_.probeM().writeProbe(index, sValues, vValues); } } // set force on particle if(treatExplicit_) for(int j=0;j<3;j++) expForces()[index][j] += drag[j]; else //implicit treatment, taking explicit force contribution into account { for(int j=0;j<3;j++) { impForces()[index][j] += drag[j] - dragExplicit[j]; //only consider implicit part! expForces()[index][j] += dragExplicit[j]; } } for(int j=0;j<3;j++) DEMForces()[index][j] += drag[j]; } //} }
void CalculateDragForce ( cfdemCloud& sm, const volScalarField& alpf_, const volVectorField& Uf_, const volScalarField& rho_, const bool& verbose_, vectorField& DragForce_, const labelListList& particleList_ ) { // get viscosity field #ifdef comp const volScalarField nufField = sm.turbulence().mu()/rho_; #else const volScalarField& nufField = sm.turbulence().nu(); #endif // Local variables label cellI(-1); vector drag(0,0,0); vector Ufluid(0,0,0); vector position(0,0,0); scalar voidfraction(1); vector Up(0,0,0); vector Ur(0,0,0); scalar ds(0); scalar nuf(0); scalar rhof(0); vector WenYuDrag(0,0,0); interpolationCellPoint<scalar> voidfractionInterpolator_(alpf_); interpolationCellPoint<vector> UInterpolator_(Uf_); // //_AO_Parallel DragForce_.resize(particleList_.size()); for(int ii =0; ii < particleList_.size(); ii++) { int index = particleList_[ii][0]; cellI = sm.cellIDs()[index][0]; drag = vector(0,0,0); Ufluid = vector(0,0,0); WenYuDrag = vector(0,0,0); DragForce_[ii] = vector(0,0,0); if (cellI > -1) // particle Found { position = sm.position(index); if ( alpf_[cellI] > 1. ) Pout << " voidfraction > 1 " << alpf_[cellI] << endl; voidfraction = voidfractionInterpolator_.interpolate(position,cellI); Ufluid = UInterpolator_.interpolate(position,cellI); if ( voidfraction > 1. ) { Pout << " Int. voidfraction > 1 " << " value= " << voidfraction; voidfraction = alpf_[cellI]; Pout << " mod. value = " << voidfraction << endl; } Up = sm.velocity(index); Ur = Ufluid-Up; ds = 2*sm.radius(index); rhof = rho_[cellI]; nuf = nufField[cellI]; // Drag force WenYuDragForce(Ur,ds,rhof,nuf,voidfraction,WenYuDrag); if(verbose_ && index <= 1) { Info << "" << endl; Pout << " index = " << index << endl; Pout << " position = " << position << endl; Pout << " Up = " << Up << endl; Pout << " Ur = " << Ur << endl; Pout << " dp = " << ds << endl; Pout << " rho = " << rhof << endl; Pout << " nuf = " << nuf << endl; Pout << " voidfraction = " << voidfraction << endl; Pout << " drag = " << WenYuDrag << endl; Info << " " << endl; } } for(int j=0;j<3;j++) DragForce_[ii][j] = WenYuDrag[j]; } }
void EulerianParticleVelocityForce ( cfdemCloud& sm, const fvMesh& mesh, volVectorField& Uf_, volVectorField& Up_, volScalarField& rho_, volScalarField& alpf_, volScalarField& Pg_, volVectorField& MappedDragForce_, const labelListList& particleList_, const bool& weighting_ ) { // Neighbouring cells CPCCellToCellStencil neighbourCells(mesh); // get viscosity field #ifdef comp const volScalarField nufField = sm.turbulence().mu()/rho_; #else const volScalarField& nufField = sm.turbulence().nu(); #endif // Gas pressure gradient volVectorField gradPg_ = fvc::grad(Pg_); interpolationCellPoint<vector> gradPgInterpolator_(gradPg_); // Local variables label cellID(-1); vector drag(0,0,0); vector Ufluid(0,0,0); vector position(0,0,0); scalar voidfraction(1); vector Up(0,0,0); vector Ur(0,0,0); scalar ds(0); scalar nuf(0); scalar rhof(0); vector WenYuDrag(0,0,0); interpolationCellPoint<scalar> voidfractionInterpolator_(alpf_); interpolationCellPoint<vector> UInterpolator_(Uf_); scalar dist_s(0); scalar sumWeights(0); scalarField weightScalar(27,scalar(0.0)); Field <Field <scalar> > particleWeights(particleList_.size(),weightScalar); //Info << " particle size " << particleList_.size() << endl; // Number of particle in a cell scalarField np(mesh.cells().size(),scalar(0)); // Particle volume scalar Volp(0); vector gradPg_int(0,0,0); for(int ii = 0; ii < particleList_.size(); ii++) { int index = particleList_[ii][0]; cellID = sm.cellIDs()[index][0]; position = sm.position(index); Ufluid = UInterpolator_.interpolate(position,cellID); Up = sm.velocity(index); Ur = Ufluid-Up; ds = 2*sm.radius(index); // Calculate WenYu Drag voidfraction = voidfractionInterpolator_.interpolate(position,cellID); nuf = nufField[cellID]; rhof = rho_[cellID]; WenYuDragForce(Ur,ds,rhof,nuf,voidfraction,WenYuDrag); Volp = ds*ds*ds*M_PI/6; gradPg_int = gradPgInterpolator_.interpolate(position,cellID); //if (cellID > -1) // particle centre is in domain //{ if(weighting_) { labelList& cellsNeigh = neighbourCells[cellID]; sumWeights = 0; dist_s = 0; //Info << " index = " << index << " ii = " << ii << " cellID = " << cellID << endl; forAll(cellsNeigh,jj) { // Find distances between particle and neighbouring cells dist_s = mag(sm.mesh().C()[cellsNeigh[jj]]-position)/pow(sm.mesh().V()[cellsNeigh[jj]],1./3.); if(dist_s <= 0.5) { particleWeights[ii][jj] = 1./4.*pow(dist_s,4)-5./8.*pow(dist_s,2)+115./192.; } else if (dist_s > 0.5 && dist_s <= 1.5) { particleWeights[ii][jj] = -1./6.*pow(dist_s,4)+5./6.*pow(dist_s,3)-5./4.*pow(dist_s,2)+5./24.*dist_s+55./96.; } else if (dist_s > 1.5 && dist_s <= 2.5) { particleWeights[ii][jj] = pow(2.5-dist_s,4)/24.; } else { particleWeights[ii][jj] = 0; } sumWeights += particleWeights[ii][jj]; } forAll(cellsNeigh,jj) { if ( sumWeights != 0 ) { Up_[cellID] += Up*particleWeights[ii][jj]/sumWeights; MappedDragForce_[cellID] += (WenYuDrag + Volp * gradPg_int) * particleWeights[ii][jj]/sumWeights; } else { Up_[cellID] = vector(0,0,0); MappedDragForce_[cellID] = vector(0,0,0); } } } else {
void DiFeliceDrag::setForce() const { // get viscosity field #ifdef comp const volScalarField nufField = particleCloud_.turbulence().mu() / rho_; #else const volScalarField& nufField = particleCloud_.turbulence().nu(); #endif vector position(0,0,0); scalar voidfraction(1); vector Ufluid(0,0,0); vector drag(0,0,0); label cellI=0; vector Us(0,0,0); vector Ur(0,0,0); scalar ds(0); scalar nuf(0); scalar rho(0); scalar magUr(0); scalar Rep(0); scalar Cd(0); interpolationCellPoint<scalar> voidfractionInterpolator_(voidfraction_); interpolationCellPoint<vector> UInterpolator_(U_); #include "setupProbeModel.H" for(int index = 0;index < particleCloud_.numberOfParticles(); index++) { //if(mask[index][0]) //{ cellI = particleCloud_.cellIDs()[index][0]; drag = vector(0,0,0); if (cellI > -1) // particle Found { if(interpolation_) { position = particleCloud_.position(index); voidfraction = voidfractionInterpolator_.interpolate(position,cellI); Ufluid = UInterpolator_.interpolate(position,cellI); }else { voidfraction = voidfraction_[cellI]; Ufluid = U_[cellI]; } Us = particleCloud_.velocity(index); Ur = Ufluid-Us; ds = 2*particleCloud_.radius(index); nuf = nufField[cellI]; rho = rho_[cellI]; magUr = mag(Ur); Rep = 0; Cd = 0; if (magUr > 0) { // calc particle Re Nr Rep = ds*voidfraction*magUr/(nuf+SMALL); // calc fluid drag Coeff Cd = sqr(0.63 + 4.8/sqrt(Rep)); // calc model coefficient Xi scalar Xi = 3.7 - 0.65 * exp(-sqr(1.5-log10(Rep))/2); // calc particle's drag drag = 0.125*Cd*rho*M_PI*ds*ds*pow(voidfraction,(2-Xi))*magUr*Ur; if (modelType_=="B") drag /= voidfraction; } if(verbose_ && index >100 && index <102) { Pout << "index = " << index << endl; Pout << "Us = " << Us << endl; Pout << "Ur = " << Ur << endl; Pout << "ds = " << ds << endl; Pout << "rho = " << rho << endl; Pout << "nuf = " << nuf << endl; Pout << "voidfraction = " << voidfraction << endl; Pout << "Rep = " << Rep << endl; Pout << "Cd = " << Cd << endl; Pout << "drag = " << drag << endl; } //Set value fields and write the probe if(probeIt_) { #include "setupProbeModelfields.H" vValues.append(drag); //first entry must the be the force vValues.append(Ur); sValues.append(Rep); sValues.append(Cd); sValues.append(voidfraction); particleCloud_.probeM().writeProbe(index, sValues, vValues); } } // set force on particle if(treatExplicit_) for(int j=0;j<3;j++) expForces()[index][j] += drag[j]; else for(int j=0;j<3;j++) impForces()[index][j] += drag[j]; for(int j=0;j<3;j++) DEMForces()[index][j] += drag[j]; } //} }
void KochHillDrag::setForce() const { if (scaleDia_ > 1) Info << "KochHill using scale = " << scaleDia_ << endl; else if (particleCloud_.cg() > 1){ scaleDia_=particleCloud_.cg(); Info << "KochHill using scale from liggghts cg = " << scaleDia_ << endl; } // get viscosity field #ifdef comp const volScalarField nufField = particleCloud_.turbulence().mu()/rho_; #else const volScalarField& nufField = particleCloud_.turbulence().nu(); #endif vector position(0,0,0); scalar voidfraction(1); vector Ufluid(0,0,0); vector drag(0,0,0); label cellI=0; vector Us(0,0,0); vector Ur(0,0,0); scalar ds(0); scalar nuf(0); scalar rho(0); scalar magUr(0); scalar Rep(0); scalar Vs(0); scalar volumefraction(0); scalar betaP(0); interpolationCellPoint<scalar> voidfractionInterpolator_(voidfraction_); interpolationCellPoint<vector> UInterpolator_(U_); #include "setupProbeModel.H" for(int index = 0;index < particleCloud_.numberOfParticles(); index++) { //if(mask[index][0]) //{ cellI = particleCloud_.cellIDs()[index][0]; drag = vector(0,0,0); betaP = 0; Vs = 0; Ufluid =vector(0,0,0); voidfraction=0; if (cellI > -1) // particle Found { if(interpolation_) { position = particleCloud_.position(index); voidfraction = voidfractionInterpolator_.interpolate(position,cellI); Ufluid = UInterpolator_.interpolate(position,cellI); //Ensure interpolated void fraction to be meaningful // Info << " --> voidfraction: " << voidfraction << endl; if(voidfraction>1.00) voidfraction = 1.00; if(voidfraction<0.40) voidfraction = 0.40; }else { voidfraction = voidfraction_[cellI]; Ufluid = U_[cellI]; } Us = particleCloud_.velocity(index); Ur = Ufluid-Us; ds = particleCloud_.d(index); nuf = nufField[cellI]; rho = rho_[cellI]; magUr = mag(Ur); Rep = 0; Vs = ds*ds*ds*M_PI/6; volumefraction = 1-voidfraction+SMALL; if (magUr > 0) { // calc particle Re Nr Rep = ds/scaleDia_*voidfraction*magUr/(nuf+SMALL); // calc model coefficient F0 scalar F0=0.; if(volumefraction < 0.4) { F0 = (1+3*sqrt((volumefraction)/2)+135/64*volumefraction*log(volumefraction) +16.14*volumefraction )/ (1+0.681*volumefraction-8.48*sqr(volumefraction) +8.16*volumefraction*volumefraction*volumefraction ); } else { F0 = 10*volumefraction/(voidfraction*voidfraction*voidfraction); } // calc model coefficient F3 scalar F3 = 0.0673+0.212*volumefraction+0.0232/pow(voidfraction,5); //Calculate F scalar F = voidfraction * (F0 + 0.5*F3*Rep); // calc drag model coefficient betaP betaP = 18.*nuf*rho/(ds/scaleDia_*ds/scaleDia_)*voidfraction*F; // calc particle's drag drag = Vs*betaP*Ur*scaleDrag_; if (modelType_=="B") drag /= voidfraction; } if(verbose_ && index >=0 && index <2) { Pout << "cellI = " << cellI << endl; Pout << "index = " << index << endl; Pout << "Us = " << Us << endl; Pout << "Ur = " << Ur << endl; Pout << "ds = " << ds << endl; Pout << "ds/scale = " << ds/scaleDia_ << endl; Pout << "rho = " << rho << endl; Pout << "nuf = " << nuf << endl; Pout << "voidfraction = " << voidfraction << endl; Pout << "Rep = " << Rep << endl; Pout << "betaP = " << betaP << endl; Pout << "drag = " << drag << endl; } //Set value fields and write the probe if(probeIt_) { #include "setupProbeModelfields.H" vValues.append(drag); //first entry must the be the force vValues.append(Ur); sValues.append(Rep); sValues.append(betaP); sValues.append(voidfraction); particleCloud_.probeM().writeProbe(index, sValues, vValues); } } // set force on particle if(treatExplicit_) for(int j=0;j<3;j++) expForces()[index][j] += drag[j]; else for(int j=0;j<3;j++) impForces()[index][j] += drag[j]; // set Cd if(implDEM_) { for(int j=0;j<3;j++) fluidVel()[index][j]=Ufluid[j]; if (modelType_=="B" && cellI > -1) Cds()[index][0] = Vs*betaP/voidfraction*scaleDrag_; else Cds()[index][0] = Vs*betaP*scaleDrag_; }else{ for(int j=0;j<3;j++) DEMForces()[index][j] += drag[j]; } //} } }