From bad26bee71be1b56c0cc41e4bedbf491b5832567 Mon Sep 17 00:00:00 2001 From: Henry Weller Date: Tue, 1 May 2018 15:59:00 +0100 Subject: [PATCH] solidificationMeltingSource: Added support for non-isothermal phase-change Requires the following changes to the corresponding entry in the fvOptions dictionary: i. Use Tsol instead Tmelt as previously to define melting temperature in isothermal phase change (for pure substance or eutectic mixture -> Tsol = Tliq); ii. Optionally define new Tliq > Tsol to consider liquidus temperature in non-isothermal phase change (for miscible mixture), where previous defined Tsol defines solidus temperature; iii. optionally define also alpha1e to consider max eutectic melt fraction (that should be the percentage of solvent phase changed from initial to eutectic liquid concentration) in partially isothermal (at Tsol=Teutectic) and non-isothermal (from Tsol=Teutectic to Tliq) phase change (for solid not miscible mixture) (alpha1e=0 -> pure substance; alpha1e=1 -> eutectic mixture that is strictely not permitted). Description This source is designed to model the effect of solidification and melting processes, e.g. windhield defrosting. The isotherm phase change occurs at the melting temperature, \c Tsol (= \c Tliq). The not isotherm phase change occurs between solidus and liquidus temperature, \c Tsol < \c Tliq respectively, as long as the melt fraction is greater than the max eutectic melt fraction, \c alpha1e (0 = pure_substance, 1 = eutectic_mixture is not permitted) , i.e. eutectic to initial solvent concentration difference, where a linear eutectic melt fraction to temperature relation is considered - lever rule. The presence of the solid phase in the flow field is incorporated into the model as a momentum porosity contribution; the energy associated with the phase change is added as an enthalpy contribution. References: \verbatim Voller, V. R., & Prakash, C. (1987). A fixed grid numerical modelling methodology for convection-diffusion mushy region phase-change problems. International Journal of Heat and Mass Transfer, 30(8), 1709-1719. Swaminathan, C. R., & Voller, V. R. (1992). A general enthalpy method for modeling solidification processes. Metallurgical transactions B, 23(5), 651-664. \endverbatim The model generates the field \c \:alpha1 which can be visualised to to show the melt distribution as a fraction [0-1]. Usage Example usage: \verbatim solidificationMeltingSource1 { type solidificationMeltingSource; active yes; selectionMode cellZone; cellZone iceZone; Tsol 273; L 334000; thermoMode thermo; beta 50e-6; rhoRef 800; } \endverbatim Where: \table Property | Description | Required | Default value Tsol | Solidus temperature [K] | yes | Tliq | Liquidus temperature [K] | no | Tsol alpha1e | Max eutectic melt fraction [0-1[ | no | 0 L | Latent heat of fusion [J/kg] | yes | relax | Relaxation coefficient [0-1] | no | 0.9 thermoMode | Thermo mode [thermo|lookup] | yes | rhoRef | Reference (solid) density [kg/m^3] | yes | rho | Name of density field | no | rho T | Name of temperature field | no | T Cp | Name of specific heat field | no | Cp U | Name of velocity field | no | U phi | Name of flux field | no | phi Cu | Model coefficient [1/s] | no | 100000 q | Model coefficient | no | 0.001 beta | Thermal expansion coefficient [1/K] | yes | g | Accelerartion due to gravity | no | \endtable Patch contributed by Lorenzo Trevisan and integrated by CFD Direct. Resolves patch request https://bugs.openfoam.org/view.php?id=2907 --- .../solidificationMeltingSource.C | 342 ++++++++++++++++++ .../solidificationMeltingSource.H | 289 +++++++++++++++ 2 files changed, 631 insertions(+) create mode 100644 src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSource.C create mode 100644 src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSource.H diff --git a/src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSource.C b/src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSource.C new file mode 100644 index 000000000..5f336ca33 --- /dev/null +++ b/src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSource.C @@ -0,0 +1,342 @@ +/*---------------------------------------------------------------------------*\ + ========= | + \\ / F ield | OpenFOAM: The Open Source CFD Toolbox + \\ / O peration | + \\ / A nd | Copyright (C) 2014-2018 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 . + +\*---------------------------------------------------------------------------*/ + +#include "solidificationMeltingSource.H" +#include "fvMatrices.H" +#include "basicThermo.H" +#include "uniformDimensionedFields.H" +#include "zeroGradientFvPatchFields.H" +#include "extrapolatedCalculatedFvPatchFields.H" +#include "addToRunTimeSelectionTable.H" +#include "geometricOneField.H" + +// * * * * * * * * * * * * * Static Member Functions * * * * * * * * * * * * // + +namespace Foam +{ + template<> + const char* NamedEnum + < + fv::solidificationMeltingSource::thermoMode, + 2 + >::names[] = + { + "thermo", + "lookup" + }; + + namespace fv + { + defineTypeNameAndDebug(solidificationMeltingSource, 0); + + addToRunTimeSelectionTable + ( + option, + solidificationMeltingSource, + dictionary + ); + } +} + +const Foam::NamedEnum + Foam::fv::solidificationMeltingSource::thermoModeTypeNames_; + + +// * * * * * * * * * * * * * Private Member Functions * * * * * * * * * * * // + +Foam::tmp +Foam::fv::solidificationMeltingSource::Cp() const +{ + switch (mode_) + { + case mdThermo: + { + const basicThermo& thermo = + mesh_.lookupObject(basicThermo::dictName); + + return thermo.Cp(); + break; + } + case mdLookup: + { + if (CpName_ == "CpRef") + { + scalar CpRef = readScalar(coeffs_.lookup("CpRef")); + + return tmp + ( + new volScalarField + ( + IOobject + ( + name_ + ":Cp", + mesh_.time().timeName(), + mesh_, + IOobject::NO_READ, + IOobject::NO_WRITE + ), + mesh_, + dimensionedScalar + ( + "Cp", + dimEnergy/dimMass/dimTemperature, + CpRef + ), + extrapolatedCalculatedFvPatchScalarField::typeName + ) + ); + } + else + { + return mesh_.lookupObject(CpName_); + } + + break; + } + default: + { + FatalErrorInFunction + << "Unhandled thermo mode: " << thermoModeTypeNames_[mode_] + << abort(FatalError); + } + } + + return tmp(nullptr); +} + + +Foam::vector Foam::fv::solidificationMeltingSource::g() const +{ + if (mesh_.foundObject("g")) + { + const uniformDimensionedVectorField& value = + mesh_.lookupObject("g"); + return value.value(); + } + else + { + return coeffs_.lookup("g"); + } +} + + +void Foam::fv::solidificationMeltingSource::update(const volScalarField& Cp) +{ + if (curTimeIndex_ == mesh_.time().timeIndex()) + { + return; + } + + if (debug) + { + Info<< type() << ": " << name_ << " - updating phase indicator" << endl; + } + + // update old time alpha1 field + alpha1_.oldTime(); + + const volScalarField& T = mesh_.lookupObject(TName_); + + forAll(cells_, i) + { + const label celli = cells_[i]; + + const scalar Tc = T[celli]; + const scalar Cpc = Cp[celli]; + const scalar alpha1New = + alpha1_[celli] + + relax_*Cpc + *( + Tc + - max + ( + Tsol_, + Tsol_ + + (Tliq_ - Tsol_)*(alpha1_[celli] - alpha1e_)/(1 - alpha1e_) + ) + )/L_; + + alpha1_[celli] = max(0, min(alpha1New, 1)); + deltaT_[i] = + Tc + - max + ( + Tsol_, + Tsol_ + + (Tliq_ - Tsol_)*(alpha1_[celli] - alpha1e_)/(1 - alpha1e_) + ); + } + + alpha1_.correctBoundaryConditions(); + + curTimeIndex_ = mesh_.time().timeIndex(); +} + + +// * * * * * * * * * * * * * * * * Constructors * * * * * * * * * * * * * * // + +Foam::fv::solidificationMeltingSource::solidificationMeltingSource +( + const word& sourceName, + const word& modelType, + const dictionary& dict, + const fvMesh& mesh +) +: + cellSetOption(sourceName, modelType, dict, mesh), + Tsol_(readScalar(coeffs_.lookup("Tsol"))), + Tliq_(coeffs_.lookupOrDefault("Tliq", Tsol_)), + alpha1e_(coeffs_.lookupOrDefault("alpha1e", 0)), + L_(readScalar(coeffs_.lookup("L"))), + relax_(coeffs_.lookupOrDefault("relax", 0.9)), + mode_(thermoModeTypeNames_.read(coeffs_.lookup("thermoMode"))), + rhoRef_(readScalar(coeffs_.lookup("rhoRef"))), + TName_(coeffs_.lookupOrDefault("T", "T")), + CpName_(coeffs_.lookupOrDefault("Cp", "Cp")), + UName_(coeffs_.lookupOrDefault("U", "U")), + phiName_(coeffs_.lookupOrDefault("phi", "phi")), + Cu_(coeffs_.lookupOrDefault("Cu", 100000)), + q_(coeffs_.lookupOrDefault("q", 0.001)), + beta_(readScalar(coeffs_.lookup("beta"))), + alpha1_ + ( + IOobject + ( + name_ + ":alpha1", + mesh.time().timeName(), + mesh, + IOobject::READ_IF_PRESENT, + IOobject::AUTO_WRITE + ), + mesh, + dimensionedScalar("alpha1", dimless, 0), + zeroGradientFvPatchScalarField::typeName + ), + curTimeIndex_(-1), + deltaT_(cells_.size(), 0) +{ + fieldNames_.setSize(2); + fieldNames_[0] = UName_; + + switch (mode_) + { + case mdThermo: + { + const basicThermo& thermo = + mesh_.lookupObject(basicThermo::dictName); + + fieldNames_[1] = thermo.he().name(); + break; + } + case mdLookup: + { + fieldNames_[1] = TName_; + break; + } + default: + { + FatalErrorInFunction + << "Unhandled thermo mode: " << thermoModeTypeNames_[mode_] + << abort(FatalError); + } + } + + applied_.setSize(fieldNames_.size(), false); +} + + +// * * * * * * * * * * * * * * * Member Functions * * * * * * * * * * * * * // + +void Foam::fv::solidificationMeltingSource::addSup +( + fvMatrix& eqn, + const label fieldi +) +{ + apply(geometricOneField(), eqn); +} + + +void Foam::fv::solidificationMeltingSource::addSup +( + const volScalarField& rho, + fvMatrix& eqn, + const label fieldi +) +{ + apply(rho, eqn); +} + + +void Foam::fv::solidificationMeltingSource::addSup +( + fvMatrix& eqn, + const label fieldi +) +{ + if (debug) + { + Info<< type() << ": applying source to " << eqn.psi().name() << endl; + } + + const volScalarField Cp(this->Cp()); + + update(Cp); + + vector g = this->g(); + + scalarField& Sp = eqn.diag(); + vectorField& Su = eqn.source(); + const scalarField& V = mesh_.V(); + + forAll(cells_, i) + { + const label celli = cells_[i]; + + const scalar Vc = V[celli]; + const scalar alpha1c = alpha1_[celli]; + + const scalar S = -Cu_*sqr(1.0 - alpha1c)/(pow3(alpha1c) + q_); + const vector Sb = rhoRef_*g*beta_*deltaT_[i]; + + Sp[celli] += Vc*S; + Su[celli] += Vc*Sb; + } +} + + +void Foam::fv::solidificationMeltingSource::addSup +( + const volScalarField& rho, + fvMatrix& eqn, + const label fieldi +) +{ + // Momentum source uses a Boussinesq approximation - redirect + addSup(eqn, fieldi); +} + + +// ************************************************************************* // diff --git a/src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSource.H b/src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSource.H new file mode 100644 index 000000000..441ee1a08 --- /dev/null +++ b/src/fvOptions/sources/derived/solidificationMeltingSource/solidificationMeltingSource.H @@ -0,0 +1,289 @@ +/*---------------------------------------------------------------------------*\ + ========= | + \\ / F ield | OpenFOAM: The Open Source CFD Toolbox + \\ / O peration | + \\ / A nd | Copyright (C) 2014-2018 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 . + +Class + Foam::fv::solidificationMeltingSource + +Description + This source is designed to model the effect of solidification and melting + processes, e.g. windhield defrosting. + + The isotherm phase change occurs at the melting temperature, \c Tsol (= \c + Tliq). The not isotherm phase change occurs between solidus and liquidus + temperature, \c Tsol < \c Tliq respectively, as long as the melt fraction is + greater than the max eutectic melt fraction, \c alpha1e (0 = + pure_substance, 1 = eutectic_mixture is not permitted) , i.e. eutectic to + initial solvent concentration difference, where a linear eutectic melt + fraction to temperature relation is considered - lever rule. + + The presence of the solid phase in the flow field is incorporated into the + model as a momentum porosity contribution; the energy associated with the + phase change is added as an enthalpy contribution. + + References: + \verbatim + Voller, V. R., & Prakash, C. (1987). + A fixed grid numerical modelling methodology for convection-diffusion + mushy region phase-change problems. + International Journal of Heat and Mass Transfer, 30(8), 1709-1719. + + Swaminathan, C. R., & Voller, V. R. (1992). + A general enthalpy method for modeling solidification processes. + Metallurgical transactions B, 23(5), 651-664. + \endverbatim + + The model generates the field \c \:alpha1 which can be visualised to + to show the melt distribution as a fraction [0-1]. + +Usage + Example usage: + \verbatim + solidificationMeltingSource1 + { + type solidificationMeltingSource; + active yes; + + selectionMode cellZone; + cellZone iceZone; + + Tsol 273; + L 334000; + thermoMode thermo; + beta 50e-6; + rhoRef 800; + } + \endverbatim + + Where: + \table + Property | Description | Required | Default value + Tsol | Solidus temperature [K] | yes | + Tliq | Liquidus temperature [K] | no | Tsol + alpha1e | Max eutectic melt fraction [0-1[ | no | 0 + L | Latent heat of fusion [J/kg] | yes | + relax | Relaxation coefficient [0-1] | no | 0.9 + thermoMode | Thermo mode [thermo|lookup] | yes | + rhoRef | Reference (solid) density [kg/m^3] | yes | + rho | Name of density field | no | rho + T | Name of temperature field | no | T + Cp | Name of specific heat field | no | Cp + U | Name of velocity field | no | U + phi | Name of flux field | no | phi + Cu | Model coefficient [1/s] | no | 100000 + q | Model coefficient | no | 0.001 + beta | Thermal expansion coefficient [1/K] | yes | + g | Accelerartion due to gravity | no | + \endtable + +SourceFiles + solidificationMeltingSource.C + solidificationMeltingSourceIO.C + +\*---------------------------------------------------------------------------*/ + +#ifndef solidificationMeltingSource_H +#define solidificationMeltingSource_H + +#include "fvMesh.H" +#include "volFields.H" +#include "cellSetOption.H" +#include "NamedEnum.H" + +// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // + +namespace Foam +{ +namespace fv +{ + +/*---------------------------------------------------------------------------*\ + Class solidificationMeltingSource Declaration +\*---------------------------------------------------------------------------*/ + +class solidificationMeltingSource +: + public cellSetOption +{ +public: + + enum thermoMode + { + mdThermo, + mdLookup + }; + + static const NamedEnum thermoModeTypeNames_; + + +private: + + // Private data + + //- Temperature at which isotherm melting occurs + // and not isotherm melting starts e.g. eutectic [K] + scalar Tsol_; + + //- Temperature at which not isotherm melting stops (Tliq > Tsol) [K] + scalar Tliq_; + + //- Max eutectic melt fraction [0-1[ + // where 0 = pure substance is default value, + // 1 = eutectic mixture is not permitted + scalar alpha1e_; + + //- Latent heat of fusion [J/kg] + scalar L_; + + //- Phase fraction under-relaxation coefficient + scalar relax_; + + //- Thermodynamics mode + thermoMode mode_; + + //- Reference density - typically the solid density + scalar rhoRef_; + + //- Name of temperature field - default = "T" (optional) + word TName_; + + //- Name of specific heat capacity field - default = "Cp" (optional) + word CpName_; + + //- Name of velocity field - default = "U" (optional) + word UName_; + + //- Name of flux field - default = "phi" (optional) + word phiName_; + + //- Mushy region momentum sink coefficient [1/s]; default = 10^5 + scalar Cu_; + + //- Coefficient used in porosity calc - default = 0.001 + scalar q_; + + //- Thermal expansion coefficient [1/K] + scalar beta_; + + //- Phase fraction indicator field + volScalarField alpha1_; + + //- Current time index (used for updating) + label curTimeIndex_; + + //- Temperature change cached for source calculation when alpha1 updated + scalarField deltaT_; + + + // Private Member Functions + + //- Return the specific heat capacity field + tmp Cp() const; + + //- Return the gravity vector + vector g() const; + + //- Update the model + void update(const volScalarField& Cp); + + //- Helper function to apply to the energy equation + template + void apply(const RhoFieldType& rho, fvMatrix& eqn); + + //- Disallow default bitwise copy construct + solidificationMeltingSource(const solidificationMeltingSource&); + + //- Disallow default bitwise assignment + void operator=(const solidificationMeltingSource&); + + +public: + + //- Runtime type information + TypeName("solidificationMeltingSource"); + + + // Constructors + + //- Construct from explicit source name and mesh + solidificationMeltingSource + ( + const word& sourceName, + const word& modelType, + const dictionary& dict, + const fvMesh& mesh + ); + + + // Member Functions + + // Add explicit and implicit contributions + + //- Add explicit contribution to enthalpy equation + virtual void addSup(fvMatrix& eqn, const label fieldi); + + //- Add implicit contribution to momentum equation + virtual void addSup(fvMatrix& eqn, const label fieldi); + + + // Add explicit and implicit contributions to compressible equation + + //- Add explicit contribution to compressible enthalpy equation + virtual void addSup + ( + const volScalarField& rho, + fvMatrix& eqn, + const label fieldi + ); + + //- Add implicit contribution to compressible momentum equation + virtual void addSup + ( + const volScalarField& rho, + fvMatrix& eqn, + const label fieldi + ); + + + // IO + + //- Read source dictionary + virtual bool read(const dictionary& dict); +}; + + +// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // + +} // End namespace fv +} // End namespace Foam + +// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // + +#ifdef NoRepository + #include "solidificationMeltingSourceTemplates.C" +#endif + +// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // + +#endif + +// ************************************************************************* //