turbulenceModels/RAS/LRR: Added optional Gibson-Launder wall-reflection

src/TurbulenceModels/turbulenceModels/RAS/LRR/LRR.C

@@ -24,6 +24,7 @@ License
 \*---------------------------------------------------------------------------*/
 
 #include "LRR.H"
+#include "wallFvPatch.H"
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
@@ -80,38 +81,38 @@ LRR<BasicTurbulenceModel>::LRR
             0.09
         )
     ),
-    Clrr1_
+    C1_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "Clrr1",
+            "C1",
             this->coeffDict_,
             1.8
         )
     ),
-    Clrr2_
+    C2_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "Clrr2",
+            "C2",
             this->coeffDict_,
             0.6
         )
     ),
-    C1_
+    Ceps1_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "C1",
+            "Ceps1",
             this->coeffDict_,
             1.44
         )
     ),
-    C2_
+    Ceps2_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "C2",
+            "Ceps2",
             this->coeffDict_,
             1.92
         )
@@ -135,6 +136,43 @@ LRR<BasicTurbulenceModel>::LRR
         )
     ),
 
+    wallReflection_
+    (
+        Switch::lookupOrAddToDict
+        (
+            "wallReflection",
+            this->coeffDict_,
+            true
+        )
+    ),
+    kappa_
+    (
+        dimensioned<scalar>::lookupOrAddToDict
+        (
+            "kappa",
+            this->coeffDict_,
+            0.41
+        )
+    ),
+    Cref1_
+    (
+        dimensioned<scalar>::lookupOrAddToDict
+        (
+            "Cref1",
+            this->coeffDict_,
+            0.5
+        )
+    ),
+    Cref2_
+    (
+        dimensioned<scalar>::lookupOrAddToDict
+        (
+            "Cref2",
+            this->coeffDict_,
+            0.3
+        )
+    ),
+
     k_
     (
         IOobject
@@ -179,10 +217,10 @@ bool LRR<BasicTurbulenceModel>::read()
     if (ReynoldsStress<RASModel<BasicTurbulenceModel> >::read())
     {
         Cmu_.readIfPresent(this->coeffDict());
-        Clrr1_.readIfPresent(this->coeffDict());
-        Clrr2_.readIfPresent(this->coeffDict());
         C1_.readIfPresent(this->coeffDict());
         C2_.readIfPresent(this->coeffDict());
+        Ceps1_.readIfPresent(this->coeffDict());
+        Ceps2_.readIfPresent(this->coeffDict());
         Cs_.readIfPresent(this->coeffDict());
         Ceps_.readIfPresent(this->coeffDict());
 
@@ -228,8 +266,8 @@ void LRR<BasicTurbulenceModel>::correct()
       + fvm::div(alphaRhoPhi, epsilon_)
       - fvm::laplacian(Ceps_*alpha*rho*(k_/epsilon_)*R, epsilon_)
      ==
-        C1_*alpha*rho*G*epsilon_/k_
-      - fvm::Sp(C2_*alpha*rho*epsilon_/k_, epsilon_)
+        Ceps1_*alpha*rho*G*epsilon_/k_
+      - fvm::Sp(Ceps2_*alpha*rho*epsilon_/k_, epsilon_)
     );
 
     epsEqn().relax();
@@ -268,13 +306,29 @@ void LRR<BasicTurbulenceModel>::correct()
         fvm::ddt(alpha, rho, R)
       + fvm::div(alphaRhoPhi, R)
       - fvm::laplacian(Cs_*alpha*rho*(k_/epsilon_)*R, R)
-      + fvm::Sp(Clrr1_*alpha*rho*epsilon_/k_, R)
+      + fvm::Sp(C1_*alpha*rho*epsilon_/k_, R)
       ==
         alpha*rho*P
-      - (2.0/3.0*(1 - Clrr1_)*I)*alpha*rho*epsilon_
-      - Clrr2_*alpha*rho*dev(P)
+      - (2.0/3.0*(1 - C1_)*I)*alpha*rho*epsilon_
+      - C2_*alpha*rho*dev(P)
     );
 
+    // Optionally add wall-refection term
+    if (wallReflection_)
+    {
+        const volVectorField& n_(wallDist::New(this->mesh_).n());
+        const volScalarField& y_(wallDist::New(this->mesh_).y());
+
+        const volSymmTensorField reflect
+        (
+            Cref1_*R - ((Cref2_*C2_)*(k_/epsilon_))*dev(P)
+        );
+
+        REqn() +=
+            ((3*pow(Cmu_, 0.75)/kappa_)*(alpha*rho*sqrt(k_)/y_))
+           *dev(symm((n_ & reflect)*n_));
+    }
+
     REqn().relax();
     solve(REqn);
 

src/TurbulenceModels/turbulenceModels/RAS/LRR/LRR.H

@@ -46,17 +46,31 @@ Description
         Physics of Fluids (1958-1988), 13(11), 2634-2649.
     \endverbatim
 
+    Optional Gibson-Launder wall-reflection is also provided:
+    \verbatim
+        Gibson, M. M., & Launder, B. E. (1978).
+        Ground effects on pressure fluctuations in the
+        atmospheric boundary layer.
+        Journal of Fluid Mechanics, 86(03), 491-511.
+    \endverbatim
+
     The default model coefficients are:
     \verbatim
         LRRCoeffs
         {
-            Cmu         0.09;
-            Clrr1       1.8;
-            Clrr2       0.6;
-            C1          1.44;
-            C2          1.92;
-            Cs          0.25;
-            Ceps        0.15;
+            Cmu             0.09;
+            C1              1.8;
+            C2              0.6;
+            Ceps1           1.44;
+            Ceps2           1.92;
+            Cs              0.25;
+            Ceps            0.15;
+
+            wallReflection  yes;
+            kappa           0.41
+            Cref1           0.5;
+            Cref2           0.3;
+
             couplingFactor  0.0;
         }
     \endverbatim
@@ -103,15 +117,23 @@ protected:
 
             dimensionedScalar Cmu_;
 
-            dimensionedScalar Clrr1_;
-            dimensionedScalar Clrr2_;
-
             dimensionedScalar C1_;
             dimensionedScalar C2_;
+
+            dimensionedScalar Ceps1_;
+            dimensionedScalar Ceps2_;
             dimensionedScalar Cs_;
             dimensionedScalar Ceps_;
 
 
+        // Wall-refection coefficients
+
+            Switch wallReflection_;
+            dimensionedScalar kappa_;
+            dimensionedScalar Cref1_;
+            dimensionedScalar Cref2_;
+
+
         // Fields
 
             volScalarField k_;