Adding new MixedDiffuseSpecular wall collision model.

src/lagrangian/dsmc/parcels/derived/dsmcParcel/makeDsmcParcelWallInteractionModels.C

@@ -28,6 +28,7 @@ License
 #include "DsmcCloud.H"
 #include "MaxwellianThermal.H"
 #include "SpecularReflection.H"
+#include "MixedDiffuseSpecular.H"
 
 namespace Foam
 {
@@ -46,6 +47,12 @@ namespace Foam
         DsmcCloud,
         dsmcParcel
     );
+    makeWallInteractionModelType
+    (
+        MixedDiffuseSpecular,
+        DsmcCloud,
+        dsmcParcel
+    );
 };
 
 

src/lagrangian/dsmc/submodels/WallInteractionModel/MixedDiffuseSpecular/MixedDiffuseSpecular.C

@@ -0,0 +1,140 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2009-2009 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 2 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, write to the Free Software Foundation,
+    Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+\*---------------------------------------------------------------------------*/
+
+#include "MixedDiffuseSpecular.H"
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+template <class CloudType>
+Foam::MixedDiffuseSpecular<CloudType>::MixedDiffuseSpecular
+(
+    const dictionary& dict,
+    CloudType& cloud
+)
+:
+    WallInteractionModel<CloudType>(dict, cloud, typeName),
+    diffuseFraction_(readScalar(this->coeffDict().lookup("diffuseFraction")))
+{}
+
+
+// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
+
+template <class CloudType>
+Foam::MixedDiffuseSpecular<CloudType>::~MixedDiffuseSpecular()
+{}
+
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+template <class CloudType>
+void Foam::MixedDiffuseSpecular<CloudType>::correct
+(
+    const wallPolyPatch& wpp,
+    const label faceId,
+    vector& U,
+    scalar& Ei,
+    label typeId
+)
+{
+    label wppIndex = wpp.index();
+
+    label wppLocalFace = wpp.whichFace(faceId);
+
+    vector nw = wpp.faceAreas()[wppLocalFace];
+
+    // Normal unit vector
+    nw /= mag(nw);
+
+    // Normal velocity magnitude
+    scalar magUn = U & nw;
+
+    CloudType& cloud(this->owner());
+
+    Random& rndGen(cloud.rndGen());
+
+    if (diffuseFraction_ > rndGen.scalar01())
+    {
+        // Diffuse reflection
+
+        // Wall tangential velocity (flow direction)
+        vector Ut = U - magUn*nw;
+
+        while (mag(Ut) < SMALL)
+        {
+            // If the incident velocity is parallel to the face normal, no
+            // tangential direction can be chosen.  Add a perturbation to the
+            // incoming velocity and recalculate.
+
+            U = vector
+            (
+                U.x()*(0.8 + 0.2*rndGen.scalar01()),
+                U.y()*(0.8 + 0.2*rndGen.scalar01()),
+                U.z()*(0.8 + 0.2*rndGen.scalar01())
+            );
+
+            magUn = U & nw;
+
+            Ut = U - magUn*nw;
+        }
+
+        // Wall tangential unit vector
+        vector tw1 = Ut/mag(Ut);
+
+        // Other tangential unit vector
+        vector tw2 = nw^tw1;
+
+        scalar T = cloud.T().boundaryField()[wppIndex][wppLocalFace];
+
+        scalar mass = cloud.constProps(typeId).mass();
+
+        scalar iDof = cloud.constProps(typeId).internalDegreesOfFreedom();
+
+        U =
+        sqrt(CloudType::kb*T/mass)
+       *(
+            rndGen.GaussNormal()*tw1
+          + rndGen.GaussNormal()*tw2
+          - sqrt(-2.0*log(max(1 - rndGen.scalar01(), VSMALL)))*nw
+        );
+
+        U += cloud.U().boundaryField()[wppIndex][wppLocalFace];
+
+        Ei = cloud.equipartitionInternalEnergy(T, iDof);
+    }
+    else
+    {
+        // Specular reflection
+
+        if (magUn > 0.0)
+        {
+            U -= 2.0*magUn*nw;
+        }
+    }
+
+}
+
+
+// ************************************************************************* //

src/lagrangian/dsmc/submodels/WallInteractionModel/MixedDiffuseSpecular/MixedDiffuseSpecular.H

@@ -0,0 +1,106 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2009-2009 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 2 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, write to the Free Software Foundation,
+    Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+Class
+    Foam::MixedDiffuseSpecular
+
+Description
+    Wall interaction setting microscopic velocity to a random one drawn from a
+    Maxwellian distribution corresponding to a specified temperature
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef MixedDiffuseSpecular_H
+#define MixedDiffuseSpecular_H
+
+#include "WallInteractionModel.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+/*---------------------------------------------------------------------------*\
+                    Class MixedDiffuseSpecular Declaration
+\*---------------------------------------------------------------------------*/
+
+template<class CloudType>
+class MixedDiffuseSpecular
+:
+    public WallInteractionModel<CloudType>
+{
+    // Private data
+
+        //- Fraction of wall interactions that are diffuse
+        scalar diffuseFraction_;
+
+
+public:
+
+    //- Runtime type information
+    TypeName("MixedDiffuseSpecular");
+
+
+    // Constructors
+
+        //- Construct from dictionary
+        MixedDiffuseSpecular
+        (
+            const dictionary& dict,
+            CloudType& cloud
+        );
+
+
+    // Destructor
+    virtual ~MixedDiffuseSpecular();
+
+
+    // Member Functions
+
+        //- Apply wall correction
+        virtual void correct
+        (
+            const wallPolyPatch& wpp,
+            const label faceId,
+            vector& U,
+            scalar& Ei,
+            label typeId
+        );
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#ifdef NoRepository
+#   include "MixedDiffuseSpecular.C"
+#endif
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //