ENH: fvOptions - added new acousticDampingSource to damp spurious pressure perturbations

src/fvOptions/Make/files

@@ -12,6 +12,7 @@ $(generalSources)/codedSource/codedSource.C
 $(generalSources)/semiImplicitSource/semiImplicitSource.C
 
 derivedSources=sources/derived
+$(derivedSources)/acousticDampingSource/acousticDampingSource.C
 $(derivedSources)/actuationDiskSource/actuationDiskSource.C
 $(derivedSources)/buoyancyForce/buoyancyForce.C
 $(derivedSources)/buoyancyForce/buoyancyForceIO.C

src/fvOptions/sources/derived/acousticDampingSource/acousticDampingSource.C

@@ -0,0 +1,218 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2016 OpenCFD Ltd.
+     \\/     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 "acousticDampingSource.H"
+#include "fvMesh.H"
+#include "fvMatrices.H"
+#include "fvmSup.H"
+#include "addToRunTimeSelectionTable.H"
+#include "mathematicalConstants.H"
+#include "zeroGradientFvPatchFields.H"
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+
+namespace Foam
+{
+namespace fv
+{
+    defineTypeNameAndDebug(acousticDampingSource, 0);
+    addToRunTimeSelectionTable
+    (
+        option,
+        acousticDampingSource,
+        dictionary
+    );
+}
+}
+
+
+// * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
+
+void Foam::fv::acousticDampingSource::setBlendingFactor()
+{
+    blendFactor_.internalField() = 1;
+
+    const vectorField& Cf = mesh_.C();
+
+    const scalar pi = constant::mathematical::pi;
+ 
+    forAll(cells_, i)
+    {
+        label celli = cells_[i];
+        scalar d = mag(Cf[celli] - x0_);
+
+        if (d < r1_)
+        {
+            blendFactor_[celli] = 0.0;
+        }
+        else if ((d >= r1_) && (d <= (r1_ + r2_)))
+        {
+            blendFactor_[celli] = (1.0 - cos(pi*mag(d - r1_)/r2_))/2.0;
+        }
+    }
+
+    blendFactor_.correctBoundaryConditions();
+}
+
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+Foam::fv::acousticDampingSource::acousticDampingSource
+(
+    const word& name,
+    const word& modelType,
+    const dictionary& dict,
+    const fvMesh& mesh
+)
+:
+    cellSetOption(name, modelType, dict, mesh),
+    frequency_("frequency", dimless/dimTime, 0),
+    blendFactor_
+    (
+        volScalarField
+        (
+            IOobject
+            (
+                name_ + ":blend",
+                mesh_.time().timeName(),
+                mesh_,
+                IOobject::NO_READ,
+                IOobject::NO_WRITE
+            ),
+            mesh_,
+            dimensionedScalar("blend0", dimless, 1.0),
+            zeroGradientFvPatchField<vector>::typeName
+        )
+    ),
+    URefName_("unknown-URefName"),
+    x0_(Zero),
+    r1_(0),
+    r2_(0),
+    w_(20)
+{
+    read(dict);
+}
+
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+void Foam::fv::acousticDampingSource::addSup
+(
+    fvMatrix<vector>& eqn,
+    const label fieldI
+)
+{
+    const volVectorField& U = eqn.psi();
+    const volScalarField coeff(name_ + ":coeff", w_*frequency_*blendFactor_);
+    const volVectorField& URef(mesh().lookupObject<volVectorField>(URefName_));
+
+    fvMatrix<vector> dampingEqn
+    (
+        fvm::Sp(coeff, U) - coeff*URef
+    );
+    eqn -= dampingEqn;
+}
+
+
+void Foam::fv::acousticDampingSource::addSup
+(
+    const volScalarField& rho,
+    fvMatrix<vector>& eqn,
+    const label fieldI
+)
+{
+    const volVectorField& U = eqn.psi();
+    const volScalarField coeff(name_ + ":coeff", w_*frequency_*blendFactor_);
+    const volVectorField& URef(mesh().lookupObject<volVectorField>(URefName_));
+
+    fvMatrix<vector> dampingEqn
+    (
+        fvm::Sp(rho*coeff, U) - rho*coeff*URef
+    );
+    eqn -= dampingEqn;
+}
+
+
+void Foam::fv::acousticDampingSource::addSup
+(
+    const volScalarField& alpha,
+    const volScalarField& rho,
+    fvMatrix<vector>& eqn,
+    const label fieldI
+)
+{
+    const volVectorField& U = eqn.psi();
+    const volScalarField coeff(name_ + ":coeff", w_*frequency_*blendFactor_);
+    const volVectorField& URef(mesh().lookupObject<volVectorField>(URefName_));
+
+    fvMatrix<vector> dampingEqn
+    (
+        fvm::Sp(alpha*rho*coeff, U) - alpha*rho*coeff*URef
+    );
+    eqn -= dampingEqn;
+}
+
+
+bool Foam::fv::acousticDampingSource::read(const dictionary& dict)
+{
+    if (cellSetOption::read(dict))
+    {
+        if (coeffs_.found("UNames"))
+        {
+            coeffs_.lookup("UNames") >> fieldNames_;
+        }
+        else if (coeffs_.found("UName"))
+        {
+            word UName(coeffs_.lookup("UName"));
+            fieldNames_ = wordList(1, UName);
+        }
+        else
+        {
+            fieldNames_ = wordList(1, "U");
+        }
+
+        applied_.setSize(fieldNames_.size(), false);
+
+        coeffs_.lookup("frequency") >> frequency_.value();
+        coeffs_.lookup("URef") >> URefName_;
+        coeffs_.lookup("centre") >> x0_;
+        coeffs_.lookup("radius1") >> r1_;
+        coeffs_.lookup("radius2") >> r2_;
+
+        if (coeffs_.readIfPresent("w", w_))
+        {
+            Info<< name_ << ": Setting stencil width to " << w_ << endl;
+        }
+
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
+
+// ************************************************************************* //

src/fvOptions/sources/derived/acousticDampingSource/acousticDampingSource.H

@@ -0,0 +1,184 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2016 OpenCFD Ltd.
+     \\/     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::acousticDampingSource
+
+Group
+    grpFvOptionsSources
+
+Description
+    Acoustic damping source
+
+    \heading Source usage
+
+    Example usage:
+    \verbatim
+    acousticDampingSourceCoeffs
+    {
+    }
+    \endverbatim
+
+SourceFiles
+    acousticDampingSource.C
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef acousticDampingSource_H
+#define acousticDampingSource_H
+
+#include "cellSetOption.H"
+#include "volFields.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+
+class porosityModel;
+
+namespace fv
+{
+
+
+/*---------------------------------------------------------------------------*\
+                    Class acousticDampingSource Declaration
+\*---------------------------------------------------------------------------*/
+
+class acousticDampingSource
+:
+    public cellSetOption
+{
+
+protected:
+
+    // Protected data
+
+        //- Frequency [Hz]
+        dimensionedScalar frequency_;
+
+        //- Blending factor []
+        volScalarField blendFactor_;
+
+        //- Name of reference velocity field
+        word URefName_;
+
+        // Sphere centre location or damping
+        point x0_;
+
+        // Inner radius at which to start damping
+        scalar r1_;
+
+        // Outer radius beyond which damping is applied
+        scalar r2_;
+
+        //- Stencil width, default = 20
+        label w_;
+
+
+    // Protected Member Functions
+
+        //- Helper function to set the blending factor
+        void setBlendingFactor();
+
+
+private:
+
+    // Private Member Functions
+
+        //- Disallow default bitwise copy construct
+        acousticDampingSource(const acousticDampingSource&);
+
+        //- Disallow default bitwise assignment
+        void operator=(const acousticDampingSource&) = delete;
+
+
+public:
+
+    //- Runtime type information
+    TypeName("acousticDampingSource");
+
+
+    // Constructors
+
+        //- Construct from components
+        acousticDampingSource
+        (
+            const word& name,
+            const word& modelType,
+            const dictionary& dict,
+            const fvMesh& mesh
+        );
+
+
+    //- Destructor
+    virtual ~acousticDampingSource()
+    {}
+
+
+    // Member Functions
+
+        // Add explicit and implicit contributions
+
+            //- Add implicit contribution to momentum equation
+            virtual void addSup
+            (
+                fvMatrix<vector>& eqn,
+                const label fieldI
+            );
+
+            //- Add implicit contribution to compressible momentum equation
+            virtual void addSup
+            (
+                const volScalarField& rho,
+                fvMatrix<vector>& eqn,
+                const label fieldI
+            );
+
+            //- Add implicit contribution to phase momentum equation
+            virtual void addSup
+            (
+                const volScalarField& alpha,
+                const volScalarField& rho,
+                fvMatrix<vector>& eqn,
+                const label fieldI
+            );
+
+
+        // IO
+
+            //- Read dictionary
+            virtual bool read(const dictionary& dict);
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace fv
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //