zhyang-dev/OpenFOAM-12
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

turbulenceModels/laminar: Maxwell, Giesekus: Added multi-mode support

Browse Source 
By specifying a list of coefficients in turbulenceProperties, e.g. for the
generalised Maxwell model:

        modes
        (
            {
                lambda          0.01;
            }

            {
                lambda          0.04;
            }
        );

of for the generalised Giesekus model:

        modes
        (
            {
                lambda          0.01;
                alphaG          0.05;
            }

            {
                lambda          0.04;
                alphaG          0.2;
            }
        );

Visco-elasticity stress tensors (sigma0, sigma1...) are solved for each mode and
summed to create the effective stress of the complex fluid:

Any number of modes can be specified and if only one mode is required the
'modes' entry is not read and the coefficients are obtained as before.

The mode sigma? fields are read if present otherwise are constructed and
initialised from the sigma field but all of the mode sigma? fields are written
for restart and the sigma field contains the sum.

    References:
        http://en.wikipedia.org/wiki/Generalized_Maxwell_model

        Wiechert, E. (1889). Ueber elastische Nachwirkung.
        (Doctoral dissertation, Hartungsche buchdr.).

        Wiechert, E. (1893).
        Gesetze der elastischen Nachwirkung für constante Temperatur.
        Annalen der Physik, 286(11), 546-570.
This commit is contained in:
Henry Weller
2020-03-11 23:24:08 +00:00
parent 262a3366f9
commit a7eb350536
5 changed files with 285 additions and 60 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
src/TurbulenceModels/turbulenceModels/laminar/Giesekus/Giesekus.C
View File

@ -2,7 +2,7 @@
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Copyright (C) 2019 OpenFOAM Foundation
\\ / A nd | Copyright (C) 2019-2020 OpenFOAM Foundation
\\/ M anipulation |
-------------------------------------------------------------------------------
License
@ -60,7 +60,7 @@ Giesekus<BasicTurbulenceModel>::Giesekus
type
),
alphaG_("alphaG", dimless, this->coeffDict_)
alphaGs_(this->readModeCoefficients("alphaG", dimless))
{
if (type == typeName)
{
@ -76,7 +76,7 @@ bool Giesekus<BasicTurbulenceModel>::read()
{
if (Maxwell<BasicTurbulenceModel>::read())
{
alphaG_.read(this->coeffDict());
alphaGs_ = this->readModeCoefficients("alphaG", dimless);
return true;
}
@ -89,12 +89,16 @@ bool Giesekus<BasicTurbulenceModel>::read()
template<class BasicTurbulenceModel>
tmp<fvSymmTensorMatrix>
Giesekus<BasicTurbulenceModel>::sigmaSource() const
Giesekus<BasicTurbulenceModel>::sigmaSource
(
const label modei,
volSymmTensorField& sigma
) const
{
return fvm::Su
(
this->alpha_*this->rho_
*alphaG_*innerSqr(this->sigma_)/this->nuM_, this->sigma_
*alphaGs_[modei]*innerSqr(sigma)/this->nuM_, sigma
);
}

15
src/TurbulenceModels/turbulenceModels/laminar/Giesekus/Giesekus.H
View File

@ -2,7 +2,7 @@
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Copyright (C) 2019 OpenFOAM Foundation
\\ / A nd | Copyright (C) 2019-2020 OpenFOAM Foundation
\\/ M anipulation |
-------------------------------------------------------------------------------
License
@ -25,7 +25,8 @@ Class
Foam::laminarModels::Giesekus
Description
Giesekus model for viscoelasticity.
Giesekus model for viscoelasticity using the upper-convected time
derivative of the stress tensor with support for multiple modes.
Reference:
\verbatim
@ -68,14 +69,18 @@ protected:
// Protected data
// Model coefficients
// Mode coefficients
dimensionedScalar alphaG_;
PtrList<dimensionedScalar> alphaGs_;
// Protected Member Functions
virtual tmp<fvSymmTensorMatrix> sigmaSource() const;
virtual tmp<fvSymmTensorMatrix> sigmaSource
(
const label modei,
volSymmTensorField& sigma
) const;
public:

208
src/TurbulenceModels/turbulenceModels/laminar/Maxwell/Maxwell.C
View File

@ -2,7 +2,7 @@
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Copyright (C) 2016-2019 OpenFOAM Foundation
\\ / A nd | Copyright (C) 2016-2020 OpenFOAM Foundation
\\/ M anipulation |
-------------------------------------------------------------------------------
License
@ -37,14 +37,75 @@ namespace laminarModels
// * * * * * * * * * * * * Protected Member Functions * * * * * * * * * * * //
template<class BasicTurbulenceModel>
tmp<fvSymmTensorMatrix> Maxwell<BasicTurbulenceModel>::sigmaSource() const
Foam::PtrList<Foam::dimensionedScalar>
Maxwell<BasicTurbulenceModel>::readModeCoefficients
(
const word& name,
const dimensionSet& dims
) const
{
PtrList<dimensionedScalar> modeCoeffs(nModes_);
if (nModes_ > 1)
{
if (this->coeffDict().found(name))
{
IOWarningInFunction(this->coeffDict())
<< "For multi-mode entry '" << name << "' will be ignored."
<< endl;
}
forAll(modeCoefficients_, modei)
{
modeCoeffs.set
(
modei,
new dimensioned<scalar>
(
name,
dims,
modeCoefficients_[modei].lookup(name)
)
);
}
}
else
{
if (modeCoefficients_.size() == 1)
{
IOWarningInFunction(this->coeffDict())
<< "For single mode 'modes' entry will be ignored." << endl;
}
modeCoeffs.set
(
0,
new dimensioned<scalar>
(
name,
dims,
this->coeffDict_.lookup(name)
)
);
}
return modeCoeffs;
}
template<class BasicTurbulenceModel>
tmp<fvSymmTensorMatrix> Maxwell<BasicTurbulenceModel>::sigmaSource
(
const label modei,
volSymmTensorField& sigma
) const
{
return tmp<fvSymmTensorMatrix>
(
new fvSymmTensorMatrix
(
sigma_,
dimVolume*this->rho_.dimensions()*sigma_.dimensions()/dimTime
sigma,
dimVolume*this->rho_.dimensions()*sigma.dimensions()/dimTime
)
);
}
@ -77,6 +138,18 @@ Maxwell<BasicTurbulenceModel>::Maxwell
propertiesName
),
modeCoefficients_
(
this->coeffDict().found("modes")
? PtrList<dictionary>
(
this->coeffDict().lookup("modes")
)
: PtrList<dictionary>()
),
nModes_(modeCoefficients_.size() ? modeCoefficients_.size() : 1),
nuM_
(
dimensioned<scalar>
@ -87,15 +160,7 @@ Maxwell<BasicTurbulenceModel>::Maxwell
)
),
lambda_
(
dimensioned<scalar>
(
"lambda",
dimTime,
this->coeffDict_.lookup("lambda")
)
),
lambdas_(readModeCoefficients("lambda", dimTime)),
sigma_
(
@ -110,6 +175,65 @@ Maxwell<BasicTurbulenceModel>::Maxwell
this->mesh_
)
{
if (nModes_ > 1)
{
sigmas_.setSize(nModes_);
forAll(sigmas_, modei)
{
IOobject header
(
IOobject::groupName("sigma" + name(modei), alphaRhoPhi.group()),
this->runTime_.timeName(),
this->mesh_,
IOobject::NO_READ
);
// Check if mode field exists and can be read
if (header.typeHeaderOk<volSymmTensorField>(true))
{
Info<< " Reading mode stress field "
<< header.name() << endl;
sigmas_.set
(
modei,
new volSymmTensorField
(
IOobject
(
header.name(),
this->runTime_.timeName(),
this->mesh_,
IOobject::MUST_READ,
IOobject::AUTO_WRITE
),
this->mesh_
)
);
}
else
{
sigmas_.set
(
modei,
new volSymmTensorField
(
IOobject
(
header.name(),
this->runTime_.timeName(),
this->mesh_,
IOobject::NO_READ,
IOobject::AUTO_WRITE
),
sigma_
)
);
}
}
}
if (type == typeName)
{
this->printCoeffs(type);
@ -124,8 +248,14 @@ bool Maxwell<BasicTurbulenceModel>::read()
{
if (laminarModel<BasicTurbulenceModel>::read())
{
if (modeCoefficients_.size())
{
this->coeffDict().lookup("modes") >> modeCoefficients_;
}
nuM_.readIfPresent(this->coeffDict());
lambda_.readIfPresent(this->coeffDict());
lambdas_ = readModeCoefficients("lambda", dimTime);
return true;
}
@ -135,6 +265,7 @@ bool Maxwell<BasicTurbulenceModel>::read()
}
}
template<class BasicTurbulenceModel>
tmp<Foam::volSymmTensorField>
Maxwell<BasicTurbulenceModel>::R() const
@ -142,6 +273,7 @@ Maxwell<BasicTurbulenceModel>::R() const
return sigma_;
}
template<class BasicTurbulenceModel>
tmp<Foam::volSymmTensorField>
Maxwell<BasicTurbulenceModel>::devRhoReff() const
@ -205,7 +337,6 @@ void Maxwell<BasicTurbulenceModel>::correct()
const rhoField& rho = this->rho_;
const surfaceScalarField& alphaRhoPhi = this->alphaRhoPhi_;
const volVectorField& U = this->U_;
volSymmTensorField& sigma = this->sigma_;
fv::options& fvOptions(fv::options::New(this->mesh_));
laminarModel<BasicTurbulenceModel>::correct();
@ -213,40 +344,67 @@ void Maxwell<BasicTurbulenceModel>::correct()
tmp<volTensorField> tgradU(fvc::grad(U));
const volTensorField& gradU = tgradU();
forAll(lambdas_, modei)
{
volSymmTensorField& sigma = nModes_ == 1 ? sigma_ : sigmas_[modei];
uniformDimensionedScalarField rLambda
(
IOobject
(
IOobject::groupName("rLambda", this->alphaRhoPhi_.group()),
IOobject::groupName
(
"rLambda"
+ (nModes_ == 1 ? word::null : name(modei)),
this->alphaRhoPhi_.group()
),
this->runTime_.constant(),
this->mesh_
),
1.0/(lambda_)
1/lambdas_[modei]
);
// Note sigma is positive on lhs of momentum eqn
volSymmTensorField P
const volSymmTensorField P
(
twoSymm(sigma & gradU)
- nuM_*rLambda*twoSymm(gradU)
);
// Viscoelastic stress equation
tmp<fvSymmTensorMatrix> sigmaEqn
fvSymmTensorMatrix sigmaEqn
(
fvm::ddt(alpha, rho, sigma)
+ fvm::div(alphaRhoPhi, sigma)
+ fvm::div
(
alphaRhoPhi,
sigma,
"div(" + alphaRhoPhi.name() + ',' + sigma_.name() + ')'
)
+ fvm::Sp(alpha*rho*rLambda, sigma)
==
alpha*rho*P
+ sigmaSource()
+ sigmaSource(modei, sigma)
+ fvOptions(alpha, rho, sigma)
);
sigmaEqn.ref().relax();
fvOptions.constrain(sigmaEqn.ref());
solve(sigmaEqn);
fvOptions.correct(sigma_);
sigmaEqn.relax();
fvOptions.constrain(sigmaEqn);
sigmaEqn.solve("sigma");
fvOptions.correct(sigma);
}
if (sigmas_.size())
{
volSymmTensorField sigmaSum("sigmaSum", sigmas_[0]);
for (label modei = 1; modei<sigmas_.size(); modei++)
{
sigmaSum += sigmas_[modei];
}
sigma_ == sigmaSum;
}
}

38
src/TurbulenceModels/turbulenceModels/laminar/Maxwell/Maxwell.H
View File

@ -2,7 +2,7 @@
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Copyright (C) 2016-2019 OpenFOAM Foundation
\\ / A nd | Copyright (C) 2016-2020 OpenFOAM Foundation
\\/ M anipulation |
-------------------------------------------------------------------------------
License
@ -25,9 +25,11 @@ Class
Foam::laminarModels::Maxwell
Description
Maxwell model for viscoelasticity using the upper-convected time
derivative of the stress tensor.
Generalised Maxwell model for viscoelasticity using the upper-convected time
derivative of the stress tensor with support for multiple modes.
See http://en.wikipedia.org/wiki/Upper-convected_Maxwell_model
http://en.wikipedia.org/wiki/Generalized_Maxwell_model
The model includes an additional viscosity (nu) from the transport
model from which it is instantiated, which makes it equivalent to
@ -37,6 +39,13 @@ Description
Reference:
\verbatim
Wiechert, E. (1889). Ueber elastische Nachwirkung.
(Doctoral dissertation, Hartungsche buchdr.).
Wiechert, E. (1893).
Gesetze der elastischen Nachwirkung für constante Temperatur.
Annalen der Physik, 286(11), 546-570.
Amoreira, L. J., & Oliveira, P. J. (2010).
Comparison of different formulations for the numerical calculation
of unsteady incompressible viscoelastic fluid flow.
@ -76,24 +85,43 @@ protected:
// Model coefficients
PtrList<dictionary> modeCoefficients_;
label nModes_;
dimensionedScalar nuM_;
dimensionedScalar lambda_;
PtrList<dimensionedScalar> lambdas_;
// Fields
//- Single or mode sum viscoelastic stress
volSymmTensorField sigma_;
//- Mode viscoelastic stresses
PtrList<volSymmTensorField> sigmas_;
// Protected Member Functions
PtrList<dimensionedScalar> readModeCoefficients
(
const word& name,
const dimensionSet& dims
) const;
//- Return the turbulence viscosity
tmp<volScalarField> nu0() const
{
return this->nu() + nuM_;
}
virtual tmp<fvSymmTensorMatrix> sigmaSource() const;
virtual tmp<fvSymmTensorMatrix> sigmaSource
(
const label modei,
volSymmTensorField& sigma
) const;
public:

30
tutorials/incompressible/pimpleFoam/laminar/planarContraction/constant/turbulenceProperties
View File

@ -23,14 +23,44 @@ laminar
MaxwellCoeffs
{
nuM 0.002;
// Single mode coefficient
lambda 0.03;
// Example 2-mode specification
// modes
// (
// {
// lambda 0.01;
// }
// {
// lambda 0.04;
// }
// );
}
GiesekusCoeffs
{
nuM 0.002;
// Single mode coefficients
lambda 0.03;
alphaG 0.1;
// Example 2-mode specification
// modes
// (
// {
// lambda 0.01;
// alphaG 0.05;
// }
// {
// lambda 0.04;
// alphaG 0.2;
// }
// );
}
printCoeffs on;