ENH: nutWallFunctions - provided option to specify alternative velocity field

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutLowReWallFunction/nutLowReWallFunctionFvPatchScalarField.C

@@ -114,7 +114,7 @@ tmp<scalarField> nutLowReWallFunctionFvPatchScalarField::yPlus() const
     const scalarField& y = turbModel.y()[patchi];
     const tmp<scalarField> tnuw = turbModel.nu(patchi);
     const scalarField& nuw = tnuw();
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
 
     return y*sqrt(nuw*mag(Uw.snGrad()))/nuw;
 }

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutUBlendedWallFunction/nutUBlendedWallFunctionFvPatchScalarField.C

@@ -44,7 +44,7 @@ Foam::nutUBlendedWallFunctionFvPatchScalarField::calcNut() const
             internalField().group()
         )
     );
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     const scalarField magGradU(mag(Uw.snGrad()));
     const tmp<scalarField> tnuw = turbModel.nu(patchi);
     const scalarField& nuw = tnuw();
@@ -80,7 +80,7 @@ Foam::nutUBlendedWallFunctionFvPatchScalarField::calcUTau
     const scalarField& nuw = tnuw();
 
     const vectorField n(patch().nf());
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     vectorField Up(Uw.patchInternalField() - Uw);
     Up -= n*(n & Up);
     const scalarField magUp(mag(Up));
@@ -197,7 +197,7 @@ Foam::nutUBlendedWallFunctionFvPatchScalarField::yPlus() const
     const scalarField& y = turbModel.y()[patchi];
     const tmp<scalarField> tnuw = turbModel.nu(patchi);
     const scalarField& nuw = tnuw();
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     const scalarField magGradU(mag(Uw.snGrad()));
 
     return y*calcUTau(magGradU)/nuw;

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutURoughWallFunction/nutURoughWallFunctionFvPatchScalarField.C

@@ -51,7 +51,7 @@ tmp<scalarField> nutURoughWallFunctionFvPatchScalarField::calcNut() const
         )
     );
     const scalarField& y = turbModel.y()[patchi];
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     const tmp<scalarField> tnuw = turbModel.nu(patchi);
     const scalarField& nuw = tnuw();
 
@@ -314,7 +314,7 @@ tmp<scalarField> nutURoughWallFunctionFvPatchScalarField::yPlus() const
             internalField().group()
         )
     );
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     tmp<scalarField> magUp = mag(Uw.patchInternalField() - Uw);
 
     return calcYPlus(magUp());

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutUSpaldingWallFunction/nutUSpaldingWallFunctionFvPatchScalarField.C

@@ -50,7 +50,7 @@ tmp<scalarField> nutUSpaldingWallFunctionFvPatchScalarField::calcNut() const
             internalField().group()
         )
     );
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     const scalarField magGradU(mag(Uw.snGrad()));
     const tmp<scalarField> tnuw = turbModel.nu(patchi);
     const scalarField& nuw = tnuw();
@@ -120,7 +120,7 @@ tmp<scalarField> nutUSpaldingWallFunctionFvPatchScalarField::calcUTau
     );
     const scalarField& y = turbModel.y()[patchi];
 
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     const scalarField magUp(mag(Uw.patchInternalField() - Uw));
 
     const tmp<scalarField> tnuw = turbModel.nu(patchi);
@@ -327,7 +327,7 @@ tmp<scalarField> nutUSpaldingWallFunctionFvPatchScalarField::yPlus() const
         )
     );
     const scalarField& y = turbModel.y()[patchi];
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     const tmp<scalarField> tnuw = turbModel.nu(patchi);
     const scalarField& nuw = tnuw();
 

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutUTabulatedWallFunction/nutUTabulatedWallFunctionFvPatchScalarField.C

@@ -51,7 +51,7 @@ tmp<scalarField> nutUTabulatedWallFunctionFvPatchScalarField::calcNut() const
         )
     );
     const scalarField& y = turbModel.y()[patchi];
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     const scalarField magUp(mag(Uw.patchInternalField() - Uw));
     const scalarField magGradU(mag(Uw.snGrad()));
     const tmp<scalarField> tnuw = turbModel.nu(patchi);
@@ -193,7 +193,7 @@ tmp<scalarField> nutUTabulatedWallFunctionFvPatchScalarField::yPlus() const
         )
     );
     const scalarField& y = turbModel.y()[patchi];
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     const scalarField magUp(mag(Uw.patchInternalField() - Uw));
     const tmp<scalarField> tnuw = turbModel.nu(patchi);
     const scalarField& nuw = tnuw();

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutUWallFunction/nutUWallFunctionFvPatchScalarField.C

@@ -50,7 +50,7 @@ tmp<scalarField> nutUWallFunctionFvPatchScalarField::calcNut() const
             internalField().group()
         )
     );
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     const scalarField magUp(mag(Uw.patchInternalField() - Uw));
     const tmp<scalarField> tnuw = turbModel.nu(patchi);
     const scalarField& nuw = tnuw();
@@ -187,7 +187,7 @@ tmp<scalarField> nutUWallFunctionFvPatchScalarField::yPlus() const
             internalField().group()
         )
     );
-    const fvPatchVectorField& Uw = turbModel.U().boundaryField()[patchi];
+    const fvPatchVectorField& Uw = U(turbModel).boundaryField()[patchi];
     const scalarField magUp(mag(Uw.patchInternalField() - Uw));
 
     return calcYPlus(magUp);

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutWallFunction/nutWallFunctionFvPatchScalarField.C

@@ -29,6 +29,7 @@ License
 #include "fvPatchFieldMapper.H"
 #include "volFields.H"
 #include "wallFvPatch.H"
+#include "turbulenceModel.H"
 #include "addToRunTimeSelectionTable.H"
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
@@ -54,11 +55,32 @@ void Foam::nutWallFunctionFvPatchScalarField::checkType()
 }
 
 
+const Foam::volVectorField& Foam::nutWallFunctionFvPatchScalarField::U
+(
+    const turbulenceModel& turb
+) const
+{
+    if (UName_ == word::null)
+    {
+        return turb.U();
+    }
+    else
+    {
+        return db().lookupObject<volVectorField>(UName_);
+    }
+}
+
+
 void Foam::nutWallFunctionFvPatchScalarField::writeLocalEntries
 (
     Ostream& os
 ) const
 {
+    if (UName_ != word::null)
+    {
+        os.writeEntry("U", UName_);
+    }
+
     os.writeEntry("Cmu", Cmu_);
     os.writeEntry("kappa", kappa_);
     os.writeEntry("E", E_);
@@ -74,6 +96,7 @@ Foam::nutWallFunctionFvPatchScalarField::nutWallFunctionFvPatchScalarField
 )
 :
     fixedValueFvPatchScalarField(p, iF),
+    UName_(word::null),
     Cmu_(0.09),
     kappa_(0.41),
     E_(9.8),
@@ -92,6 +115,7 @@ Foam::nutWallFunctionFvPatchScalarField::nutWallFunctionFvPatchScalarField
 )
 :
     fixedValueFvPatchScalarField(ptf, p, iF, mapper),
+    UName_(ptf.UName_),
     Cmu_(ptf.Cmu_),
     kappa_(ptf.kappa_),
     E_(ptf.E_),
@@ -109,6 +133,7 @@ Foam::nutWallFunctionFvPatchScalarField::nutWallFunctionFvPatchScalarField
 )
 :
     fixedValueFvPatchScalarField(p, iF, dict),
+    UName_(dict.lookupOrDefault<word>("U", word::null)),
     Cmu_(dict.lookupOrDefault<scalar>("Cmu", 0.09)),
     kappa_(dict.lookupOrDefault<scalar>("kappa", 0.41)),
     E_(dict.lookupOrDefault<scalar>("E", 9.8)),
@@ -124,6 +149,7 @@ Foam::nutWallFunctionFvPatchScalarField::nutWallFunctionFvPatchScalarField
 )
 :
     fixedValueFvPatchScalarField(wfpsf),
+    UName_(wfpsf.UName_),
     Cmu_(wfpsf.Cmu_),
     kappa_(wfpsf.kappa_),
     E_(wfpsf.E_),
@@ -140,6 +166,7 @@ Foam::nutWallFunctionFvPatchScalarField::nutWallFunctionFvPatchScalarField
 )
 :
     fixedValueFvPatchScalarField(wfpsf, iF),
+    UName_(wfpsf.UName_),
     Cmu_(wfpsf.Cmu_),
     kappa_(wfpsf.kappa_),
     E_(wfpsf.E_),

src/TurbulenceModels/turbulenceModels/derivedFvPatchFields/wallFunctions/nutWallFunctions/nutWallFunction/nutWallFunctionFvPatchScalarField.H

@@ -76,6 +76,8 @@ SourceFiles
 namespace Foam
 {
 
+class turbulenceModel;
+
 /*---------------------------------------------------------------------------*\
              Class nutWallFunctionFvPatchScalarField Declaration
 \*---------------------------------------------------------------------------*/
@@ -88,6 +90,11 @@ protected:
 
     // Protected data
 
+        //- Name of velocity field
+        //  Defult is null (not specified) in which case the velocity is
+        //  retrieved from the turbulence model
+        word UName_;
+
         //- Cmu coefficient
         scalar Cmu_;
 
@@ -103,6 +110,10 @@ protected:
 
     // Protected Member Functions
 
+        //- Helper to return the velocity field either from the turbulence
+        //- model (default) or the mesh database
+        virtual const volVectorField& U(const turbulenceModel& turb) const;
+
         //- Check the type of the patch
         virtual void checkType();