TurbulenceModels::generalizedNewtonian: New structure to support gene…

…ralized Newtonian laminar transport

Within this structure the BirdCarreau, Casson, CrossPowerLaw, HerschelBulkley,
powerLaw and strainRateFunction strain-dependent viscosity based non-Newtonian
fluid models may be selected for incompressible or compressible flow.

In the case of compressible flow the strain-dependent viscosity functions are
applied to the temperature dependent viscosity so that if the WLF viscosity
model is chosen in conjunction with the CrossPowerLaw the effective model is
Cross-WLF which is commonly used for polymer flow.

These models are selected in the constant/turbulenceProperties file, e.g.

simulationType  laminar;

laminar
{
    laminarModel generalizedNewtonian;

    viscosityModel CrossPowerLaw;

    nuInf      10;
    m          0.4;
    n          3;
}

This new implementation is more general and flexible than the previous
incompressible only non-Newtonian viscosity models, which were selected in the
constant/transportProperties file.  This implementation is now deprecated and
will be phased-out.

src/TurbulenceModels/compressible/turbulentFluidThermoModels/turbulentFluidThermoModels.C

@@ -45,6 +45,9 @@ makeBaseTurbulenceModel
 #include "Stokes.H"
 makeLaminarModel(Stokes);
 
+#include "generalizedNewtonian.H"
+makeLaminarModel(generalizedNewtonian);
+
 #include "Maxwell.H"
 makeLaminarModel(Maxwell);
 

src/TurbulenceModels/incompressible/turbulentTransportModels/turbulentTransportModels.C

@@ -44,6 +44,9 @@ makeBaseTurbulenceModel
 #include "Stokes.H"
 makeLaminarModel(Stokes);
 
+#include "generalizedNewtonian.H"
+makeLaminarModel(generalizedNewtonian);
+
 #include "Maxwell.H"
 makeLaminarModel(Maxwell);
 

src/TurbulenceModels/turbulenceModels/Make/files

@@ -63,5 +63,14 @@ RASBCs = RAS/derivedFvPatchFields
 $(RASBCs)/turbulentMixingLengthDissipationRateInlet/turbulentMixingLengthDissipationRateInletFvPatchScalarField.C
 $(RASBCs)/turbulentMixingLengthFrequencyInlet/turbulentMixingLengthFrequencyInletFvPatchScalarField.C
 
+generalizedNewtonianViscosityModels = laminar/generalizedNewtonian/generalizedNewtonianViscosityModels
+$(generalizedNewtonianViscosityModels)/generalizedNewtonianViscosityModel/generalizedNewtonianViscosityModel.C
+$(generalizedNewtonianViscosityModels)/generalizedNewtonianViscosityModel/generalizedNewtonianViscosityModelNew.C
+$(generalizedNewtonianViscosityModels)/CrossPowerLaw/CrossPowerLaw.C
+$(generalizedNewtonianViscosityModels)/BirdCarreau/BirdCarreau.C
+$(generalizedNewtonianViscosityModels)/Casson/Casson.C
+$(generalizedNewtonianViscosityModels)/HerschelBulkley/HerschelBulkley.C
+$(generalizedNewtonianViscosityModels)/powerLaw/powerLaw.C
+$(generalizedNewtonianViscosityModels)/strainRateFunction/strainRateFunction.C
 
 LIB = $(FOAM_LIBBIN)/libturbulenceModels

src/TurbulenceModels/turbulenceModels/laminar/generalizedNewtonian/generalizedNewtonian.C

@@ -0,0 +1,264 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     | Website:  https://openfoam.org
+    \\  /    A nd           | Copyright (C) 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 <http://www.gnu.org/licenses/>.
+
+\*---------------------------------------------------------------------------*/
+
+#include "generalizedNewtonian.H"
+#include "volFields.H"
+#include "surfaceFields.H"
+#include "fvcGrad.H"
+#include "fvcDiv.H"
+#include "fvmLaplacian.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+namespace laminarModels
+{
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+template<class BasicTurbulenceModel>
+generalizedNewtonian<BasicTurbulenceModel>::generalizedNewtonian
+(
+    const alphaField& alpha,
+    const rhoField& rho,
+    const volVectorField& U,
+    const surfaceScalarField& alphaRhoPhi,
+    const surfaceScalarField& phi,
+    const transportModel& transport,
+    const word& propertiesName
+)
+:
+    linearViscousStress<laminarModel<BasicTurbulenceModel>>
+    (
+        typeName,
+        alpha,
+        rho,
+        U,
+        alphaRhoPhi,
+        phi,
+        transport,
+        propertiesName
+    ),
+
+    viscosityModel_
+    (
+        generalizedNewtonianViscosityModel::New
+        (
+            this->coeffDict_
+        )
+    ),
+
+    nu_
+    (
+        IOobject
+        (
+            IOobject::groupName("generalizedNewtonian:nu", alphaRhoPhi.group()),
+            this->runTime_.timeName(),
+            this->mesh_,
+            IOobject::NO_READ,
+            IOobject::AUTO_WRITE
+        ),
+        viscosityModel_->nu(this->nu(), strainRate())
+    )
+{}
+
+
+// * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
+
+template<class BasicTurbulenceModel>
+Foam::tmp<Foam::volScalarField>
+generalizedNewtonian<BasicTurbulenceModel>::strainRate() const
+{
+    return sqrt(2.0)*mag(symm(fvc::grad(this->U())));
+}
+
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+template<class BasicTurbulenceModel>
+bool generalizedNewtonian<BasicTurbulenceModel>::read()
+{
+    viscosityModel_->read(this->coeffDict_);
+
+    return true;
+}
+
+
+template<class BasicTurbulenceModel>
+tmp<volScalarField>
+generalizedNewtonian<BasicTurbulenceModel>::nut() const
+{
+    return tmp<volScalarField>
+    (
+        new volScalarField
+        (
+            IOobject
+            (
+                IOobject::groupName("nut", this->alphaRhoPhi_.group()),
+                this->runTime_.timeName(),
+                this->mesh_,
+                IOobject::NO_READ,
+                IOobject::NO_WRITE,
+                false
+            ),
+            this->mesh_,
+            dimensionedScalar("nut", dimViscosity, 0.0)
+        )
+    );
+}
+
+
+template<class BasicTurbulenceModel>
+tmp<scalarField>
+generalizedNewtonian<BasicTurbulenceModel>::nut
+(
+    const label patchi
+) const
+{
+    return tmp<scalarField>
+    (
+        new scalarField(this->mesh_.boundary()[patchi].size(), 0.0)
+    );
+}
+
+
+template<class BasicTurbulenceModel>
+tmp<volScalarField>
+generalizedNewtonian<BasicTurbulenceModel>::nuEff() const
+{
+    return tmp<volScalarField>
+    (
+        new volScalarField
+        (
+            IOobject::groupName("nuEff", this->alphaRhoPhi_.group()), nu_
+        )
+    );
+}
+
+
+template<class BasicTurbulenceModel>
+tmp<scalarField>
+generalizedNewtonian<BasicTurbulenceModel>::nuEff
+(
+    const label patchi
+) const
+{
+    return nu_.boundaryField()[patchi];
+}
+
+
+template<class BasicTurbulenceModel>
+tmp<volScalarField>
+generalizedNewtonian<BasicTurbulenceModel>::k() const
+{
+    return tmp<volScalarField>
+    (
+        new volScalarField
+        (
+            IOobject
+            (
+                IOobject::groupName("k", this->alphaRhoPhi_.group()),
+                this->runTime_.timeName(),
+                this->mesh_,
+                IOobject::NO_READ,
+                IOobject::NO_WRITE,
+                false
+            ),
+            this->mesh_,
+            dimensionedScalar("k", sqr(this->U_.dimensions()), 0.0)
+        )
+    );
+}
+
+
+template<class BasicTurbulenceModel>
+tmp<volScalarField>
+generalizedNewtonian<BasicTurbulenceModel>::epsilon() const
+{
+    return tmp<volScalarField>
+    (
+        new volScalarField
+        (
+            IOobject
+            (
+                IOobject::groupName("epsilon", this->alphaRhoPhi_.group()),
+                this->runTime_.timeName(),
+                this->mesh_,
+                IOobject::NO_READ,
+                IOobject::NO_WRITE,
+                false
+            ),
+            this->mesh_,
+            dimensionedScalar
+            (
+                "epsilon", sqr(this->U_.dimensions())/dimTime, 0.0
+            )
+        )
+    );
+}
+
+
+template<class BasicTurbulenceModel>
+tmp<volSymmTensorField>
+generalizedNewtonian<BasicTurbulenceModel>::R() const
+{
+    return tmp<volSymmTensorField>
+    (
+        new volSymmTensorField
+        (
+            IOobject
+            (
+                IOobject::groupName("R", this->alphaRhoPhi_.group()),
+                this->runTime_.timeName(),
+                this->mesh_,
+                IOobject::NO_READ,
+                IOobject::NO_WRITE,
+                false
+            ),
+            this->mesh_,
+            dimensionedSymmTensor
+            (
+                "R", sqr(this->U_.dimensions()), Zero
+            )
+        )
+    );
+}
+
+
+template<class BasicTurbulenceModel>
+void generalizedNewtonian<BasicTurbulenceModel>::correct()
+{
+    nu_ = viscosityModel_->nu(this->nu(), strainRate());
+    laminarModel<BasicTurbulenceModel>::correct();
+}
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace laminarModels
+} // End namespace Foam
+
+// ************************************************************************* //