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========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Copyright (C) 2024-2026 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/>.
Class
Foam::fv::wallBoiling
Description
Model for nucleate wall boiling between two phases on the surface of a
number of wall patches.
This model implements a version of the well-known RPI wall boiling model
(Kurul & Podowski, 1991). The model is based on an implementation described
in Peltola et al. (2019) and is similar to the model described by Peltola &
Pättikangas (2012).
References:
\verbatim
Kurul, N., & Podowski, M.Z. (1991).
On the modeling of multidimensional effects in boiling channels.
ANS. Proc. National Heat Transfer Con. Minneapolis, Minnesota, USA,
1991.
ISBN: 0-89448-162-1, pp. 30-40.
\endverbatim
\verbatim
Peltola, J., Pättikangas, T., Bainbridge, W., Lehnigk, R., Schlegel, F.
(2019).
On Development and validation of subcooled nucleate boiling models for
OpenFOAM Foundation Release.
NURETH-18 Conference Proceedings, Portland, Oregon, United States, 2019.
\endverbatim
\verbatim
Peltola, J., & Pättikangas, T.J.H. (2012).
Development and validation of a boiling model for OpenFOAM multiphase
solver.
CFD4NRS-4 Conference Proceedings, Daejeon, Korea, 2012.
paper 59.
\endverbatim
Usage
Example usage:
\verbatim
wallBoiling
{
type wallBoiling;
libs ("libmultiphaseEulerFvModels.so");
// Note: Order is important. This model is one-way. It turns liquid
// into vapour. The phases should be specified in this order.
phases (water steam);
energySemiImplicit no;
saturationTemperature
{
type constant;
value 372.76;
}
partitioningModel
{
type Lavieville;
alphaCrit 0.2;
}
nucleationSiteModel
{
type LemmertChawla;
Cn 1;
NRef 30000000;
deltaTRef 10;
}
departureDiameterModel
{
type TolubinskiKostanchuk;
dRef 0.00024;
dMax 0.0014;
dMin 1e-06;
}
departureFrequencyModel
{
type KocamustafaogullariIshii;
Cf 1.18;
}
}
\endverbatim
In addition to the above fvModel specification, wall patches on which
boiling is to be calculated should have an alphatPhaseChangeWallFunction
boundary condition applied to the turbulent thermal diffusivity field.
See also
Foam::alphatPhaseChangeWallFunctionFvPatchScalarField
SourceFiles
wallBoiling.C
\*---------------------------------------------------------------------------*/
#ifndef wallBoiling_H
#define wallBoiling_H
#include "wallPhaseChange.H"
#include "nucleation.H"
#include "phaseSystem.H"
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
namespace Foam
{
// Forward declaration of classes
namespace wallBoilingModels
{
class partitioningModel;
class nucleationSiteModel;
class departureDiameterModel;
class departureFrequencyModel;
}
class wallBoilingPhaseChangeRateFvPatchScalarField;
namespace fv
{
/*---------------------------------------------------------------------------*\
Class wallBoiling Declaration
\*---------------------------------------------------------------------------*/
class wallBoiling
:
public wallPhaseChange,
public nucleation
{
private:
// Private classes
//- Struct to hold properties that are held constant during the
// iterative solution procedure
struct laggedProperties;
// Private Data
//- Reference to the liquid phase
const phaseModel& liquid_;
//- Reference to the vapour phase
const phaseModel& vapour_;
//- Reference to the liquid turbulent thermal diffusivity
const volScalarField& alphatLiquid_;
//- Reference to the vapour turbulent thermal diffusivity
const volScalarField& alphatVapour_;
//- Reference to the field associated with the pressure equation
const volScalarField& p_rgh_;
//- Solution tolerance
scalar tolerance_;
//- Estimate liquid temperature using logarithmic wall function?
bool liquidTemperatureWallFunction_;
//- Turbulent Prandtl number
scalar Prt_;
//- Bubble waiting time ratio
scalar bubbleWaitingTimeRatio_;
//- Saturation temperature as a function of pressure
autoPtr<Function1<scalar>> Tsat_;
//- Run-time selected heat flux partitioning model
autoPtr<wallBoilingModels::partitioningModel> partitioningModel_;
//- Run-time selected nucleation site density model
autoPtr<wallBoilingModels::nucleationSiteModel> nucleationSiteModel_;
//- Run-time selected bubble departure diameter model
autoPtr<wallBoilingModels::departureDiameterModel>
departureDiameterModel_;
//- Run-time selected bubble departure frequency model
autoPtr<wallBoilingModels::departureFrequencyModel>
departureFrequencyModel_;
//- Counter for the evaluations of the pressure equation sources
mutable label pressureEquationIndex_;
//- The phase change rate
mutable volScalarField mDot_;
// Private Member Functions
//- Non-virtual read
void readCoeffs(const dictionary& dict);
//- Get the liquid temperature patch field and the parameters
// associated with its boundary condition that are necessary for
// approximately evaluating the boundary condition's heat flux at
// a given wall temperature.
const fvPatchScalarField& getLiquidTemperaturePatchField
(
const laggedProperties& lagProps,
scalarField& isFixed,
scalarField& h,
scalarField& hTaPlusQa
) const;
//- Calculate the boiling for the given wall temperature. Return
// the total sum of all heat fluxes. Set the properties passed by
// non-const reference. Used by the functions below.
tmp<scalarField> calcBoiling
(
const laggedProperties& lagProps,
const scalarField& TLiquid,
const scalarField& wetFraction,
scalarField& dDeparture,
scalarField& fDeparture,
scalarField& nucleationSiteDensity,
scalarField& qQuenching,
scalarField& qEvaporative,
scalarField& mDot
) const;
//- Calculate the boiling for the given wall temperature. Return
// the total sum of all heat fluxes. Use this to solve the balance
// between the heat fluxes specified by the boiling models and the
// temperature boundary condition without changing the stored
// boiling state.
tmp<scalarField> calcBoiling
(
const wallBoilingPhaseChangeRateFvPatchScalarField& mDot,
const laggedProperties& lagProps,
const scalarField& TLiquid
) const;
//- Calculate the boiling for the given wall temperature. Return
// the total sum of all heat fluxes. Also set the stored boiling
// state. Use this after solving with the final wall temperature
// to set the boiling state.
tmp<scalarField> evaluateBoiling
(
wallBoilingPhaseChangeRateFvPatchScalarField& mDot,
const laggedProperties& lagProps,
const scalarField& TLiquid
) const;
//- Correct the phase change rate
void correctMDot() const;
public:
//- Runtime type information
TypeName("wallBoiling");
// Constructors
//- Construct from explicit source name and mesh
wallBoiling
(
const word& name,
const word& modelType,
const fvMesh& mesh,
const dictionary& dict
);
// Member Functions
// Access
//- Return a mask indicating whether phase change is occurring
virtual const scalarField& active(const label) const;
//- Access the turbulent thermal diffusivities for a patch
virtual Pair<const scalarField&> alphats(const label) const;
// Evaluation
//- Return the fraction of the latent heat that is transferred into
// the second phase
virtual tmp<DimensionedField<scalar, fvMesh>> Lfraction() const;
//- Return the diameter of nuclei
virtual tmp<DimensionedField<scalar, fvMesh>> d() const;
//- Return the number rate at which nuclei are generated
virtual tmp<DimensionedField<scalar, fvMesh>> nDot() const;
//- Return the nucleation time scale
virtual tmp<DimensionedField<scalar, fvMesh>> tau() const;
// Sources
//- Return the mass transfer rate
virtual tmp<DimensionedField<scalar, fvMesh>> mDot() const;
//- Return the mass transfer rate for the given patch
const wallBoilingPhaseChangeRateFvPatchScalarField& mDotPf
(
const label patchi
) const;
//- Return the mass transfer rate for the given patch
wallBoilingPhaseChangeRateFvPatchScalarField& mDotPfRef
(
const label patchi
) const;
//- Use phaseChange's source functions
using phaseChange::addSup;
//- Override the pressure equation to add the mass transfer rate
// linearised in the pressure
void addSup
(
const volScalarField& alpha,
const volScalarField& rho,
fvMatrix<scalar>& eqn
) const;
//- Correct the fvModel
virtual void correct();
// IO
//- Read source dictionary
virtual bool read(const dictionary& dict);
};
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
} // End namespace fv
} // End namespace Foam
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
#endif
// ************************************************************************* //
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