CONTRIBUTION: Turbulence - updated SpalartAlmaras & kOmegaSST DES, DDES and IDDES

Code supplied by CFD Software E+F GmbH

src/TurbulenceModels/schemes/DEShybrid/DEShybrid.H

@@ -45,7 +45,7 @@ Description
         w_2   | scheme 2 weights
     \endvartable
 
-    Reference:
+    First published in:
     \verbatim
         A. Travin, M. Shur, M. Strelets, P. Spalart (2000).
         Physical and numerical upgrades in the detached-eddy simulation of
@@ -54,6 +54,16 @@ Description
         Transition and Turbulent Flows, Munich, Germany
     \endverbatim
 
+    Original publication contained a typo for C_H3 constant. Corrected version
+    with minor changes for 2 lower limiters published in:
+    \verbatim
+        P. Spalart, M. Shur, M. Strelets, A. Travin (2012).
+        Sensitivity of Landing-Gear Noise Predictions by Large-Eddy
+        Simulation to Numerics and Resolution.
+        AIAA Paper 2012-1174, 50th AIAA Aerospace Sciences Meeting,
+        Nashville / TN, Jan. 2012
+    \endverbatim
+
     Example of the DEShybrid scheme specification using linear within the LES
     region and linearUpwind within the RAS region:
     \verbatim
@@ -65,7 +75,9 @@ Description
             linear                        // scheme 1
             linearUpwind grad(U)          // scheme 2
             0.65                          // DES coefficient, typically = 0.65
-            10                            // Reference time scale (Uref/Lref)
+            30                            // Reference velocity scale
+            2                             // Reference length scale
+            0                             // Minimum sigma limit (0-1)
             1;                            // Maximum sigma limit (0-1)
         .
         .
@@ -119,17 +131,22 @@ class DEShybrid
         //- DES Coefficient
         scalar CDES_;
 
-        //- Time scale coefficient [1/s]
+        //- Reference velocity scale [m/s]
-        dimensionedScalar invTau_;
+        dimensionedScalar U0_;
 
-        //- Maximum bound for sigma (limited to 1)
+        //- Reference length scale [m]
+        dimensionedScalar L0_;
+
+        //- Minimum bound for sigma (0 <= sigmaMin <= 1)
+        scalar sigmaMin_;
+
+        //- Maximum bound for sigma (0 <= sigmaMax <= 1)
         scalar sigmaMax_;
 
-        //- Lower limit for `B' coefficient
+        //- constants of scheme
-        dimensionedScalar B0_;
+        scalar CH1_;
-
+        scalar CH2_;
-        //- Small length scale to avoid division by zero
+        scalar CH3_;
-        dimensionedScalar d0_;
 
         //- Disallow default bitwise copy construct
         DEShybrid(const DEShybrid&);
@@ -152,31 +169,48 @@ class DEShybrid
             tmp<volTensorField> gradU(fvc::grad(U));
             const volScalarField S(sqrt(2.0)*mag(symm(gradU())));
             const volScalarField Omega(sqrt(2.0)*mag(skew(gradU())));
-            const volScalarField magSqrGradU(magSqr(gradU));
+            const dimensionedScalar tau0_ = L0_/U0_;
 
             const volScalarField B
             (
-                0.5*Omega*max(S, Omega)
+                CH3_*Omega*max(S, Omega)
-               /max(0.5*magSqrGradU, B0_)
+               /max(0.5*(sqr(S)+sqr(Omega)), sqr(1.0e-3/tau0_))
             );
             const volScalarField K
             (
-                max(Foam::sqrt(0.5*magSqrGradU), 0.1*invTau_)
+                max(Foam::sqrt(0.5*(sqr(S)+sqr(Omega))), 0.1/tau0_)
             );
+
             const volScalarField lTurb(Foam::sqrt(nuEff/(pow(0.09, 1.5)*K)));
             const volScalarField g(tanh(pow4(B)));
             const volScalarField A
             (
-                 max(scalar(0), CDES_*delta/max(lTurb*g, d0_) - 0.5)
+                 CH2_*max(scalar(0), CDES_*delta/max(lTurb*g, 1.0e-15*L0_) - 0.5)
             );
-            const surfaceScalarField Af(fvc::interpolate(A));
+
+            const volScalarField IOhybrid
+            (
+                IOobject
+                (
+                    "DEShybridFactor",
+                    this->mesh().time().timeName(),
+                    this->mesh(),
+                    IOobject::NO_READ,
+                    IOobject::NO_WRITE
+                ),
+                max(sigmaMax_*tanh(pow(A, CH1_)), sigmaMin_)
+            );
+            if (this->mesh().time().outputTime())
+            {
+                IOhybrid.write();
+            }
 
             return tmp<surfaceScalarField>
             (
                 new surfaceScalarField
                 (
                     vf.name() + "BlendingFactor",
-                    max(sigmaMax_*tanh(pow3(Af)), scalar(0))
+                    fvc::interpolate(IOhybrid)
                 )
             );
         }
@@ -205,16 +239,43 @@ public:
                 surfaceInterpolationScheme<Type>::New(mesh, is)
             ),
             CDES_(readScalar(is)),
-            invTau_("invTau", dimless/dimTime, readScalar(is)),
+            U0_("U0", dimLength/dimTime, readScalar(is)),
+            L0_("L0", dimLength, readScalar(is)),
+            sigmaMin_(readScalar(is)),
             sigmaMax_(readScalar(is)),
-            B0_("B0", dimless/sqr(dimTime), 1e-20),
+            CH1_(3.0),
-            d0_("d0", dimLength, SMALL)
+            CH2_(1.0),
+            CH3_(2.0)
         {
-            if (invTau_.value() <= 0)
+            if (U0_.value() <= 0)
             {
                 FatalErrorInFunction
-                    << "invTau coefficient must be greater than 0. "
+                    << "U0 coefficient must be greater than 0. "
-                    << "Current value: " << invTau_ << exit(FatalError);
+                    << "Current value: " << U0_ << exit(FatalError);
+            }
+            if (L0_.value() <= 0)
+            {
+                FatalErrorInFunction
+                    << "L0 coefficient must be greater than 0. "
+                    << "Current value: " << L0_ << exit(FatalError);
+            }
+            if (sigmaMin_ < 0)
+            {
+                FatalErrorInFunction
+                    << "sigmaMin coefficient must be greater than or equal to 0. "
+                    << "Current value: " << sigmaMin_ << exit(FatalError);
+            }
+            if (sigmaMax_ < 0)
+            {
+                FatalErrorInFunction
+                    << "sigmaMax coefficient must be greater than or equal to 0. "
+                    << "Current value: " << sigmaMax_ << exit(FatalError);
+            }
+            if (sigmaMin_ > 1)
+            {
+                FatalErrorInFunction
+                    << "sigmaMin coefficient must be less than or equal to 1. "
+                    << "Current value: " << sigmaMin_ << exit(FatalError);
             }
             if (sigmaMax_ > 1)
             {
@@ -242,16 +303,43 @@ public:
                 surfaceInterpolationScheme<Type>::New(mesh, faceFlux, is)
             ),
             CDES_(readScalar(is)),
-            invTau_("invTau", dimless/dimTime, readScalar(is)),
+            U0_("U0", dimLength/dimTime, readScalar(is)),
+            L0_("L0", dimLength, readScalar(is)),
+            sigmaMin_(readScalar(is)),
             sigmaMax_(readScalar(is)),
-            B0_("B0", dimless/sqr(dimTime), 1e-20),
+            CH1_(3.0),
-            d0_("d0", dimLength, SMALL)
+            CH2_(1.0),
+            CH3_(2.0)
         {
-            if (invTau_.value() <= 0)
+            if (U0_.value() <= 0)
             {
                 FatalErrorInFunction
-                    << "invTau coefficient must be greater than 0. "
+                    << "U0 coefficient must be greater than 0. "
-                    << "Current value: " << invTau_ << exit(FatalError);
+                    << "Current value: " << U0_ << exit(FatalError);
+            }
+            if (L0_.value() <= 0)
+            {
+                FatalErrorInFunction
+                    << "L0 coefficient must be greater than 0. "
+                    << "Current value: " << U0_ << exit(FatalError);
+            }
+            if (sigmaMin_ < 0)
+            {
+                FatalErrorInFunction
+                    << "sigmaMin coefficient must be greater than or equal to 0. "
+                    << "Current value: " << sigmaMin_ << exit(FatalError);
+            }
+            if (sigmaMax_ < 0)
+            {
+                FatalErrorInFunction
+                    << "sigmaMax coefficient must be greater than or equal to 0. "
+                    << "Current value: " << sigmaMax_ << exit(FatalError);
+            }
+            if (sigmaMin_ > 1)
+            {
+                FatalErrorInFunction
+                    << "sigmaMin coefficient must be less than or equal to 1. "
+                    << "Current value: " << sigmaMin_ << exit(FatalError);
             }
             if (sigmaMax_ > 1)
             {

src/TurbulenceModels/turbulenceModels/DES/SpalartAllmarasDDES/SpalartAllmarasDDES.C

@@ -68,7 +68,7 @@ tmp<volScalarField> SpalartAllmarasDDES<BasicTurbulenceModel>::fd
     const volScalarField& magGradU
 ) const
 {
-    return 1 - tanh(pow(fdFactor_*rd(magGradU), fdExponent_));
+    return 1 - tanh(pow(Cd1_*rd(magGradU), Cd2_));
 }
 
 
@@ -82,13 +82,16 @@ tmp<volScalarField> SpalartAllmarasDDES<BasicTurbulenceModel>::dTilda
     const volTensorField& gradU
 ) const
 {
+    const volScalarField lRAS(this->y_);
+    const volScalarField lLES(this->psi(chi, fv1)*this->CDES_*this->delta());
+
     return max
     (
-        this->y_
+        lRAS
       - fd(mag(gradU))
        *max
         (
-            this->y_ - this->psi(chi, fv1)*this->CDES_*this->delta(),
+            lRAS - lLES,
             dimensionedScalar("zero", dimLength, 0)
         ),
         dimensionedScalar("small", dimLength, SMALL)
@@ -119,27 +122,34 @@ SpalartAllmarasDDES<BasicTurbulenceModel>::SpalartAllmarasDDES
         alphaRhoPhi,
         phi,
         transport,
-        propertiesName
+        propertiesName,
+        type
     ),
-    fdFactor_
+
+    Cd1_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "fdFactor",
+            "Cd1",
             this->coeffDict_,
             8
         )
     ),
-    fdExponent_
+    Cd2_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "fdExponent",
+            "Cd2",
             this->coeffDict_,
             3
         )
     )
-{}
+{
+    if (type == typeName)
+    {
+        this->printCoeffs(type);
+    }
+}
 
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
@@ -149,8 +159,9 @@ bool SpalartAllmarasDDES<BasicTurbulenceModel>::read()
 {
     if (SpalartAllmarasDES<BasicTurbulenceModel>::read())
     {
-        fdFactor_.readIfPresent(this->coeffDict());
+        Cd1_.readIfPresent(this->coeffDict());
-        fdExponent_.readIfPresent(this->coeffDict());
+        Cd2_.readIfPresent(this->coeffDict());
+
         return true;
     }
     else

src/TurbulenceModels/turbulenceModels/DES/SpalartAllmarasDDES/SpalartAllmarasDDES.H

@@ -81,11 +81,10 @@ protected:
 
     // Protected data
 
-        //- fd function pre-factor
+        // Model coefficients
-        dimensionedScalar fdFactor_;
 
-        //- fd function exponent
+            dimensionedScalar Cd1_;
-        dimensionedScalar fdExponent_;
+            dimensionedScalar Cd2_;
 
 
     // Protected Member Functions

src/TurbulenceModels/turbulenceModels/DES/SpalartAllmarasDES/SpalartAllmarasDES.C

@@ -73,16 +73,6 @@ tmp<volScalarField> SpalartAllmarasDES<BasicTurbulenceModel>::ft2
 }
 
 
-template<class BasicTurbulenceModel>
-tmp<volScalarField> SpalartAllmarasDES<BasicTurbulenceModel>::S
-(
-    const volTensorField& gradU
-) const
-{
-    return sqrt(2.0)*mag(symm(gradU));
-}
-
-
 template<class BasicTurbulenceModel>
 tmp<volScalarField> SpalartAllmarasDES<BasicTurbulenceModel>::Omega
 (

src/TurbulenceModels/turbulenceModels/DES/SpalartAllmarasDES/SpalartAllmarasDES.H

@@ -133,8 +133,6 @@ protected:
 
         tmp<volScalarField> ft2(const volScalarField& chi) const;
 
-        tmp<volScalarField> S(const volTensorField& gradU) const;
-
         tmp<volScalarField> Omega(const volTensorField& gradU) const;
 
         tmp<volScalarField> Stilda

src/TurbulenceModels/turbulenceModels/DES/SpalartAllmarasIDDES/SpalartAllmarasIDDES.C

@@ -34,15 +34,24 @@ namespace LESModels
 
 // * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * * //
 
+template<class BasicTurbulenceModel>
+const IDDESDelta& SpalartAllmarasIDDES<BasicTurbulenceModel>::setDelta() const
+{
+    if (!isA<IDDESDelta>(this->delta_()))
+    {
+        FatalErrorInFunction
+            << "The delta function must be set to a " << IDDESDelta::typeName
+            << " -based model" << exit(FatalError);
+    }
+
+    return refCast<const IDDESDelta>(this->delta_());
+}
+
+
 template<class BasicTurbulenceModel>
 tmp<volScalarField> SpalartAllmarasIDDES<BasicTurbulenceModel>::alpha() const
 {
-    // Equation 9 (plus limits)
+    return max(0.25 - this->y_/IDDESDelta_.hmax(), scalar(-5));
-    return max
-    (
-        0.25 - this->y_/static_cast<const volScalarField&>(IDDESDelta_.hmax()),
-        scalar(-5)
-    );
 }
 
 
@@ -52,8 +61,7 @@ tmp<volScalarField> SpalartAllmarasIDDES<BasicTurbulenceModel>::ft
     const volScalarField& magGradU
 ) const
 {
-    // Equation 13
+    return tanh(pow3(sqr(Ct_)*rd(this->nut_, magGradU)));
-    return tanh(pow3(sqr(ct_)*rd(this->nut_, magGradU)));
 }
 
 
@@ -63,8 +71,7 @@ tmp<volScalarField> SpalartAllmarasIDDES<BasicTurbulenceModel>::fl
     const volScalarField& magGradU
 ) const
 {
-    // Equation 13
+    return tanh(pow(sqr(Cl_)*rd(this->nu(), magGradU), 10));
-    return tanh(pow(sqr(cl_)*rd(this->nu(), magGradU), 10));
 }
 
 
@@ -75,7 +82,9 @@ tmp<volScalarField> SpalartAllmarasIDDES<BasicTurbulenceModel>::rd
     const volScalarField& magGradU
 ) const
 {
-    return min
+    tmp<volScalarField> tr
+    (
+        min
         (
             nur
            /(
@@ -83,10 +92,15 @@ tmp<volScalarField> SpalartAllmarasIDDES<BasicTurbulenceModel>::rd
                 (
                     magGradU,
                     dimensionedScalar("SMALL", magGradU.dimensions(), SMALL)
-           )*sqr(this->kappa_*this->y_)
+                )
+                *sqr(this->kappa_*this->y_)
             ),
             scalar(10)
+        )
     );
+    tr().boundaryField() == 0.0;
+
+    return tr;
 }
 
 
@@ -98,8 +112,7 @@ tmp<volScalarField> SpalartAllmarasIDDES<BasicTurbulenceModel>::fdt
     const volScalarField& magGradU
 ) const
 {
-    // Related to equation 16
+    return 1 - tanh(pow(Cdt1_*rd(this->nut_, magGradU), Cdt2_));
-    return 1 - tanh(pow3(8*rd(this->nuEff(), magGradU)));
 }
 
 
@@ -111,31 +124,38 @@ tmp<volScalarField> SpalartAllmarasIDDES<BasicTurbulenceModel>::dTilda
     const volTensorField& gradU
 ) const
 {
+    const volScalarField magGradU(mag(gradU));
+    const volScalarField psi(this->psi(chi, fv1));
+
+    const volScalarField lRAS(this->y_);
+    const volScalarField lLES(psi*this->CDES_*this->delta());
+
     const volScalarField alpha(this->alpha());
     const volScalarField expTerm(exp(sqr(alpha)));
-    const volScalarField magGradU(mag(gradU));
 
-    // Equation 9
     tmp<volScalarField> fB = min(2*pow(expTerm, -9.0), scalar(1));
-
-    // Equation 11
     tmp<volScalarField> fe1 =
         2*(pos(alpha)*pow(expTerm, -11.09) + neg(alpha)*pow(expTerm, -9.0));
-
-    // Equation 12
     tmp<volScalarField> fe2 = 1 - max(ft(magGradU), fl(magGradU));
-
-    // Equation 10
-    const volScalarField psi(this->psi(chi, fv1));
     tmp<volScalarField> fe = max(fe1 - 1, scalar(0))*psi*fe2;
 
-    // Equation 16
     const volScalarField fdTilda(max(1 - fdt(magGradU), fB));
 
-    // Equation 17 (plus limits)
+    // Simplified formulation from Gritskevich et al. paper (2011) where fe = 0
+    /*
     return max
     (
-        fdTilda*(1 + fe)*this->y_ + (1 - fdTilda)*psi*this->CDES_*this->delta(),
+        fdTilda*lRAS 
+      + (1 - fdTilda)*lLES, 
+        dimensionedScalar("SMALL", dimLength, SMALL)
+    );
+    */
+
+    // Original formulation from Shur et al. paper (2008)
+    return max
+    (
+        fdTilda*(1 + fe)*lRAS 
+      + (1 - fdTilda)*lLES,
         dimensionedScalar("SMALL", dimLength, SMALL)
     );
 }
@@ -164,37 +184,53 @@ SpalartAllmarasIDDES<BasicTurbulenceModel>::SpalartAllmarasIDDES
         alphaRhoPhi,
         phi,
         transport,
-        propertiesName
+        propertiesName,
+        type
     ),
-    fwStar_
+
+    Cdt1_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "fwStar",
+            "Cdt1",
             this->coeffDict_,
-            0.424
+            8
         )
     ),
-    cl_
+    Cdt2_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "cl",
+            "Cdt2",
+            this->coeffDict_,
+            3
+        )
+    ),
+    Cl_
+    (
+        dimensioned<scalar>::lookupOrAddToDict
+        (
+            "Cl",
             this->coeffDict_,
             3.55
         )
     ),
-    ct_
+    Ct_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "ct",
+            "Ct",
             this->coeffDict_,
             1.63
         )
     ),
-    IDDESDelta_(refCast<IDDESDelta>(this->delta_()))
+    IDDESDelta_(setDelta())
-{}
+{
+    if (type == typeName)
+    {
+        this->printCoeffs(type);
+    }
+}
 
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
@@ -204,9 +240,10 @@ bool SpalartAllmarasIDDES<BasicTurbulenceModel>::read()
 {
     if (SpalartAllmarasDES<BasicTurbulenceModel>::read())
     {
-        fwStar_.readIfPresent(this->coeffDict());
+        Cdt1_.readIfPresent(this->coeffDict());
-        cl_.readIfPresent(this->coeffDict());
+        Cdt2_.readIfPresent(this->coeffDict());
-        ct_.readIfPresent(this->coeffDict());
+        Cl_.readIfPresent(this->coeffDict());
+        Ct_.readIfPresent(this->coeffDict());
 
         return true;
     }

src/TurbulenceModels/turbulenceModels/DES/SpalartAllmarasIDDES/SpalartAllmarasIDDES.H

@@ -66,21 +66,11 @@ class SpalartAllmarasIDDES
 :
     public SpalartAllmarasDES<BasicTurbulenceModel>
 {
-    // Private data
-
-        // Model constants
-
-            dimensionedScalar fwStar_;
-            dimensionedScalar cl_;
-            dimensionedScalar ct_;
-
-        // Fields
-
-            const IDDESDelta& IDDESDelta_;
-
-
     // Private Member Functions
 
+        //- Check that the supplied delta is an IDDESDelta
+        const IDDESDelta& setDelta() const;
+
         tmp<volScalarField> alpha() const;
         tmp<volScalarField> ft(const volScalarField& magGradU) const;
         tmp<volScalarField> fl(const volScalarField& magGradU) const;
@@ -101,6 +91,19 @@ class SpalartAllmarasIDDES
 
 protected:
 
+    // Protected data
+
+        // Model coefficients
+
+            dimensionedScalar Cdt1_;
+            dimensionedScalar Cdt2_;
+            dimensionedScalar Cl_;
+            dimensionedScalar Ct_;
+
+        // Fields
+
+            const IDDESDelta& IDDESDelta_;
+
     // Protected Member Functions
 
         //- Length scale

src/TurbulenceModels/turbulenceModels/DES/kOmegaSSTDDES/kOmegaSSTDDES.C

@@ -37,7 +37,6 @@ namespace LESModels
 template<class BasicTurbulenceModel>
 tmp<volScalarField> kOmegaSSTDDES<BasicTurbulenceModel>::rd
 (
-    const volScalarField& nur,
     const volScalarField& magGradU
 ) const
 {
@@ -45,7 +44,7 @@ tmp<volScalarField> kOmegaSSTDDES<BasicTurbulenceModel>::rd
     (
         min
         (
-            nur
+            this->nuEff()
            /(
                 max
                 (
@@ -69,7 +68,7 @@ tmp<volScalarField> kOmegaSSTDDES<BasicTurbulenceModel>::fd
     const volScalarField& magGradU
 ) const
 {
-    return 1 - tanh(pow(cd1_*rd(this->nuEff(), magGradU), cd2_));
+    return 1 - tanh(pow(Cd1_*rd(magGradU), Cd2_));
 }
 
 
@@ -87,9 +86,18 @@ tmp<volScalarField> kOmegaSSTDDES<BasicTurbulenceModel>::dTilda
 
     const volScalarField lRAS(sqrt(k)/(this->betaStar_*omega));
     const volScalarField lLES(CDES*this->delta());
-    const dimensionedScalar d0("SMALL", dimLength, SMALL);
 
-    return max(lRAS - fd(magGradU)*max(lRAS - lLES, d0), d0);
+    return max
+    (
+        lRAS 
+      - fd(magGradU)
+       *max
+        (
+            lRAS - lLES,
+            dimensionedScalar("zero", dimLength, 0)
+        ),
+        dimensionedScalar("small", dimLength, SMALL)
+    );
 }
 
 
@@ -120,20 +128,20 @@ kOmegaSSTDDES<BasicTurbulenceModel>::kOmegaSSTDDES
         type
     ),
 
-    cd1_
+    Cd1_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "cd1",
+            "Cd1",
             this->coeffDict_,
             20
         )
     ),
-    cd2_
+    Cd2_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "cd2",
+            "Cd2",
             this->coeffDict_,
             3
         )
@@ -153,8 +161,8 @@ bool kOmegaSSTDDES<BasicTurbulenceModel>::read()
 {
     if (kOmegaSSTDES<BasicTurbulenceModel>::read())
     {
-        cd1_.readIfPresent(this->coeffDict());
+        Cd1_.readIfPresent(this->coeffDict());
-        cd2_.readIfPresent(this->coeffDict());
+        Cd2_.readIfPresent(this->coeffDict());
 
         return true;
     }

src/TurbulenceModels/turbulenceModels/DES/kOmegaSSTDDES/kOmegaSSTDDES.H

@@ -66,14 +66,10 @@ class kOmegaSSTDDES
 {
     // Private Member Functions
 
-        tmp<volScalarField> rd
-        (
-            const volScalarField& nur,
-            const volScalarField& magGradU
-        ) const;
-
         tmp<volScalarField> fd(const volScalarField& magGradU) const;
 
+        tmp<volScalarField> rd(const volScalarField& magGradU) const;
+
         // Disallow default bitwise copy construct and assignment
         kOmegaSSTDDES(const kOmegaSSTDDES&);
         kOmegaSSTDDES& operator=(const kOmegaSSTDDES&);
@@ -85,8 +81,8 @@ protected:
 
         // Model coefficients
 
-            dimensionedScalar cd1_;
+            dimensionedScalar Cd1_;
-            dimensionedScalar cd2_;
+            dimensionedScalar Cd2_;
 
 
     // Protected Member Functions
@@ -144,11 +140,13 @@ public:
 } // End namespace Foam
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
 #ifdef NoRepository
 #   include "kOmegaSSTDDES.C"
 #endif
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
 #endif
 
 // ************************************************************************* //

src/TurbulenceModels/turbulenceModels/DES/kOmegaSSTDES/kOmegaSSTDES.C

@@ -62,12 +62,7 @@ tmp<volScalarField> kOmegaSSTDES<BasicTurbulenceModel>::dTilda
     const volScalarField& k = this->k_;
     const volScalarField& omega = this->omega_;
 
-    return
+    return min(CDES*this->delta(), sqrt(k)/(this->betaStar_*omega));
-        min
-        (
-            CDES*this->delta(),
-            sqrt(k + this->kMin_)/(this->betaStar_*omega)
-        );
 }
 
 
@@ -113,7 +108,7 @@ kOmegaSSTDES<BasicTurbulenceModel>::kOmegaSSTDES
         (
             "CDESkom",
             this->coeffDict_,
-            0.78
+            0.82
         )
     ),
     CDESkeps_
@@ -122,7 +117,7 @@ kOmegaSSTDES<BasicTurbulenceModel>::kOmegaSSTDES
         (
             "CDESkeps",
             this->coeffDict_,
-            0.61
+            0.60
         )
     )
 {

src/TurbulenceModels/turbulenceModels/DES/kOmegaSSTDES/kOmegaSSTDES.H

@@ -37,6 +37,9 @@ Description
         39th AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV
     \endverbatim
 
+    Note: DES constants CDES_kom and CDES_keps have been re-calibrated to 
+          OpenFOAM numerics via decaying isotropic turbulence test case
+
 SourceFiles
     kOmegaSSTDES.C
 

src/TurbulenceModels/turbulenceModels/DES/kOmegaSSTIDDES/kOmegaSSTIDDES.C

@@ -61,7 +61,7 @@ tmp<volScalarField> kOmegaSSTIDDES<BasicTurbulenceModel>::ft
     const volScalarField& magGradU
 ) const
 {
-    return tanh(pow3(sqr(ct_)*rd(this->nut_, magGradU)));
+    return tanh(pow3(sqr(Ct_)*rd(this->nut_, magGradU)));
 }
 
 
@@ -71,7 +71,7 @@ tmp<volScalarField> kOmegaSSTIDDES<BasicTurbulenceModel>::fl
     const volScalarField& magGradU
 ) const
 {
-    return tanh(pow(sqr(cl_)*rd(this->nu(), magGradU), 10));
+    return tanh(pow(sqr(Cl_)*rd(this->nu(), magGradU), 10));
 }
 
 
@@ -104,18 +104,18 @@ tmp<volScalarField> kOmegaSSTIDDES<BasicTurbulenceModel>::rd
 }
 
 
+// * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
+
 template<class BasicTurbulenceModel>
-tmp<volScalarField> kOmegaSSTIDDES<BasicTurbulenceModel>::fd
+tmp<volScalarField> kOmegaSSTIDDES<BasicTurbulenceModel>::fdt
 (
     const volScalarField& magGradU
 ) const
 {
-    return 1 - tanh(pow(cdt1_*rd(this->nuEff(), magGradU), cdt2_));
+    return 1 - tanh(pow(Cdt1_*rd(this->nut_, magGradU), Cdt2_));
 }
 
 
-// * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
-
 template<class BasicTurbulenceModel>
 tmp<volScalarField> kOmegaSSTIDDES<BasicTurbulenceModel>::dTilda
 (
@@ -128,22 +128,35 @@ tmp<volScalarField> kOmegaSSTIDDES<BasicTurbulenceModel>::dTilda
 
     const volScalarField lRAS(sqrt(k)/(this->betaStar_*omega));
     const volScalarField lLES(CDES*this->delta());
-    const dimensionedScalar d0("SMALL", dimLength, SMALL);
 
     const volScalarField alpha(this->alpha());
     const volScalarField expTerm(exp(sqr(alpha)));
 
-    tmp<volScalarField> fStep = min(2*pow(expTerm, -9.0), scalar(1));
+    tmp<volScalarField> fB = min(2*pow(expTerm, -9.0), scalar(1));
-    const volScalarField fHyb(max(1 - fd(magGradU), fStep));
+    tmp<volScalarField> fe1 =
-    // Simplified version where fRestore = 0
-    // return max(d0, fHyb*lRAS + (1 - fHyb)*lLES);
-
-    // Original form
-    tmp<volScalarField> fHill =
         2*(pos(alpha)*pow(expTerm, -11.09) + neg(alpha)*pow(expTerm, -9.0));
-    tmp<volScalarField> fAmp = 1 - max(ft(magGradU), fl(magGradU));
+    tmp<volScalarField> fe2 = 1 - max(ft(magGradU), fl(magGradU));
-    tmp<volScalarField> fRestore = max(fHill - 1, scalar(0))*fAmp;
+    tmp<volScalarField> fe = max(fe1 - 1, scalar(0))*fe2;
-    return max(d0, fHyb*(1 + fRestore)*lRAS + (1 - fHyb)*lLES);
+
+    const volScalarField fdTilda(max(1 - fdt(magGradU), fB));
+
+    // Simplified formulation from Gritskevich et al. paper (2011) where fe = 0
+    /*
+    return max
+    (
+        fdTilda*lRAS 
+      + (1 - fdTilda)*lLES, 
+        dimensionedScalar("SMALL", dimLength, SMALL)
+    );
+    */
+
+    // Original formulation from Shur et al. paper (2008)
+    return max
+    (
+        fdTilda*(1 + fe)*lRAS 
+      + (1 - fdTilda)*lLES,
+        dimensionedScalar("SMALL", dimLength, SMALL)
+    );
 }
 
 
@@ -173,38 +186,39 @@ kOmegaSSTIDDES<BasicTurbulenceModel>::kOmegaSSTIDDES
         propertiesName,
         type
     ),
-    cdt1_
+
+    Cdt1_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "cdt1",
+            "Cdt1",
             this->coeffDict_,
             20
         )
     ),
-    cdt2_
+    Cdt2_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "cdt2",
+            "Cdt2",
             this->coeffDict_,
             3
         )
     ),
-    cl_
+    Cl_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "cl",
+            "Cl",
             this->coeffDict_,
             5
         )
     ),
-    ct_
+    Ct_
     (
         dimensioned<scalar>::lookupOrAddToDict
         (
-            "ct",
+            "Ct",
             this->coeffDict_,
             1.87
         )
@@ -225,10 +239,10 @@ bool kOmegaSSTIDDES<BasicTurbulenceModel>::read()
 {
     if (kOmegaSSTDES<BasicTurbulenceModel>::read())
     {
-        cdt1_.readIfPresent(this->coeffDict());
+        Cdt1_.readIfPresent(this->coeffDict());
-        cdt2_.readIfPresent(this->coeffDict());
+        Cdt2_.readIfPresent(this->coeffDict());
-        cl_.readIfPresent(this->coeffDict());
+        Cl_.readIfPresent(this->coeffDict());
-        ct_.readIfPresent(this->coeffDict());
+        Ct_.readIfPresent(this->coeffDict());
 
         return true;
     }

src/TurbulenceModels/turbulenceModels/DES/kOmegaSSTIDDES/kOmegaSSTIDDES.H

@@ -81,7 +81,7 @@ class kOmegaSSTIDDES
         ) const;
 
         //- Delay function
-        tmp<volScalarField> fd(const volScalarField& maggradU) const;
+        tmp<volScalarField> fdt(const volScalarField& magGradU) const;
 
         // Disallow default bitwise copy construct and assignment
         kOmegaSSTIDDES(const kOmegaSSTIDDES&);
@@ -94,15 +94,16 @@ protected:
 
         // Model coefficients
 
-            dimensionedScalar cdt1_;
+            dimensionedScalar Cdt1_;
-            dimensionedScalar cdt2_;
+            dimensionedScalar Cdt2_;
-            dimensionedScalar cl_;
+            dimensionedScalar Cl_;
-            dimensionedScalar ct_;
+            dimensionedScalar Ct_;
 
         // Fields
 
             const IDDESDelta& IDDESDelta_;
 
+    // Protected Member Functions
 
         //- Length scale
         virtual tmp<volScalarField> dTilda
@@ -157,11 +158,13 @@ public:
 } // End namespace Foam
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
 #ifdef NoRepository
 #   include "kOmegaSSTIDDES.C"
 #endif
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
 #endif
 
 // ************************************************************************* //