Merge pull request #1208 from su2code/fix_cskin_friction

Fix skin friction coefficient

Author: pcarruscag

SU2_CFD/include/solvers/CFVMFlowSolverBase.hpp

@@ -2413,7 +2413,7 @@ class CFVMFlowSolverBase : public CSolver {
    */
   inline su2double GetCSkinFriction(unsigned short val_marker, unsigned long val_vertex,
                                     unsigned short val_dim) const final {
-    return CSkinFriction[val_marker][val_dim][val_vertex];
+    return CSkinFriction[val_marker](val_vertex,val_dim);
   }
 
   /*!

SU2_CFD/include/solvers/CFVMFlowSolverBase.inl

@@ -197,9 +197,7 @@ void CFVMFlowSolverBase<V, R>::Allocate(const CConfig& config) {
 
   /*--- Skin friction in all the markers ---*/
 
-  CSkinFriction.resize(nMarker);
-  for (iMarker = 0; iMarker < nMarker; iMarker++)
-    CSkinFriction[iMarker].resize(nDim, nVertex[iMarker]) = su2double(0.0);
+  Alloc3D(nMarker, nVertex, nDim, CSkinFriction);
 
   /*--- Wall Shear Stress in all the markers ---*/
 
@@ -2412,8 +2410,8 @@ void CFVMFlowSolverBase<V, FlowRegime>::Friction_Forces(const CGeometry* geometr
   unsigned long iVertex, iPoint, iPointNormal;
   unsigned short iMarker, iMarker_Monitoring, iDim, jDim;
   unsigned short T_INDEX = 0, TVE_INDEX = 0, VEL_INDEX = 0;
-  su2double Viscosity = 0.0, WallDist[3] = {0.0}, Area, TauNormal, RefVel2 = 0.0, dTn, dTven,
-            RefDensity = 0.0, GradTemperature, Density = 0.0, WallDistMod, FrictionVel,
+  su2double Viscosity = 0.0, WallDist[3] = {0.0}, Area, TauNormal, dTn, dTven,
+            GradTemperature, Density = 0.0, WallDistMod, FrictionVel,
             UnitNormal[3] = {0.0}, TauElem[3] = {0.0}, TauTangent[3] = {0.0}, Tau[3][3] = {{0.0}}, Cp,
             thermal_conductivity, MaxNorm = 8.0, Grad_Vel[3][3] = {{0.0}}, Grad_Temp[3] = {0.0}, AxiFactor;
   const su2double *Coord = nullptr, *Coord_Normal = nullptr, *Normal = nullptr;
@@ -2443,6 +2441,7 @@ void CFVMFlowSolverBase<V, FlowRegime>::Friction_Forces(const CGeometry* geometr
   }
 
   const su2double factor = 1.0 / AeroCoeffForceRef;
+  const su2double factorFric = config->GetRefArea() * factor;
 
   /*--- Variables initialization ---*/
 
@@ -2546,7 +2545,7 @@ void CFVMFlowSolverBase<V, FlowRegime>::Friction_Forces(const CGeometry* geometr
       WallShearStress[iMarker][iVertex] = 0.0;
       for (iDim = 0; iDim < nDim; iDim++) {
         TauTangent[iDim] = TauElem[iDim] - TauNormal * UnitNormal[iDim];
-        CSkinFriction[iMarker][iDim][iVertex] = TauTangent[iDim] / (0.5 * RefDensity * RefVel2);
+        CSkinFriction[iMarker](iVertex,iDim) = TauTangent[iDim] * factorFric;
         WallShearStress[iMarker][iVertex] += TauTangent[iDim] * TauTangent[iDim];
       }
       WallShearStress[iMarker][iVertex] = sqrt(WallShearStress[iMarker][iVertex]);

SU2_CFD/src/solvers/CNSSolver.cpp

@@ -184,16 +184,11 @@ void CNSSolver::Viscous_Residual(unsigned long iEdge, CGeometry *geometry, CSolv
 void CNSSolver::Buffet_Monitoring(const CGeometry *geometry, const CConfig *config) {
 
   unsigned long iVertex;
-  unsigned short Boundary, Monitoring, iMarker, iMarker_Monitoring, iDim;
+  unsigned short iMarker, iMarker_Monitoring;
   const su2double* Vel_FS = Velocity_Inf;
-  su2double VelMag_FS = 0.0, SkinFrictionMag = 0.0, SkinFrictionDot = 0.0, *Normal, Area, Sref = config->GetRefArea();
-  su2double k = config->GetBuffet_k(), lam = config->GetBuffet_lambda();
-  string Marker_Tag, Monitoring_Tag;
+  const su2double k = config->GetBuffet_k(), lam = config->GetBuffet_lambda(), Sref = config->GetRefArea();
 
-  for (iDim = 0; iDim < nDim; iDim++){
-    VelMag_FS += Vel_FS[iDim]*Vel_FS[iDim];
-  }
-  VelMag_FS = sqrt(VelMag_FS);
+  const su2double VelMag_FS = GeometryToolbox::Norm(nDim, Vel_FS);
 
   /*-- Variables initialization ---*/
 
@@ -209,24 +204,18 @@ void CNSSolver::Buffet_Monitoring(const CGeometry *geometry, const CConfig *conf
 
     Buffet_Metric[iMarker] = 0.0;
 
-    Boundary   = config->GetMarker_All_KindBC(iMarker);
-    Monitoring = config->GetMarker_All_Monitoring(iMarker);
+    const auto Monitoring = config->GetMarker_All_Monitoring(iMarker);
 
-    if ((Boundary == HEAT_FLUX) || (Boundary == ISOTHERMAL) || (Boundary == HEAT_FLUX) || (Boundary == CHT_WALL_INTERFACE)) {
+    if (config->GetViscous_Wall(iMarker)) {
 
       /*--- Loop over the vertices to compute the buffet sensor ---*/
 
       for (iVertex = 0; iVertex < geometry->nVertex[iMarker]; iVertex++) {
 
         /*--- Perform dot product of skin friction with freestream velocity ---*/
 
-        SkinFrictionMag = 0.0;
-        SkinFrictionDot = 0.0;
-        for(iDim = 0; iDim < nDim; iDim++){
-          SkinFrictionMag += pow(CSkinFriction[iMarker][iDim][iVertex], 2);
-          SkinFrictionDot += CSkinFriction[iMarker][iDim][iVertex]*Vel_FS[iDim];
-        }
-        SkinFrictionMag = sqrt(SkinFrictionMag);
+        const su2double SkinFrictionMag = GeometryToolbox::Norm(nDim, CSkinFriction[iMarker][iVertex]);
+        su2double SkinFrictionDot = GeometryToolbox::DotProduct(nDim, CSkinFriction[iMarker][iVertex], Vel_FS);
 
         /*--- Normalize the dot product ---*/
 
@@ -238,27 +227,28 @@ void CNSSolver::Buffet_Monitoring(const CGeometry *geometry, const CConfig *conf
 
         /*--- Integrate buffet sensor ---*/
 
-        if(Monitoring == YES){
+        if (Monitoring == YES){
 
-          Normal = geometry->vertex[iMarker][iVertex]->GetNormal();
-          Area = GeometryToolbox::Norm(nDim, Normal);
+          auto Normal = geometry->vertex[iMarker][iVertex]->GetNormal();
+          su2double Area = GeometryToolbox::Norm(nDim, Normal);
 
           Buffet_Metric[iMarker] += Buffet_Sensor[iMarker][iVertex]*Area/Sref;
 
         }
 
       }
 
-      if(Monitoring == YES){
+      if (Monitoring == YES){
 
         Total_Buffet_Metric += Buffet_Metric[iMarker];
 
         /*--- Per surface buffet metric ---*/
 
         for (iMarker_Monitoring = 0; iMarker_Monitoring < config->GetnMarker_Monitoring(); iMarker_Monitoring++) {
-          Monitoring_Tag = config->GetMarker_Monitoring_TagBound(iMarker_Monitoring);
-          Marker_Tag = config->GetMarker_All_TagBound(iMarker);
-          if (Marker_Tag == Monitoring_Tag) Surface_Buffet_Metric[iMarker_Monitoring] = Buffet_Metric[iMarker];
+          auto Monitoring_Tag = config->GetMarker_Monitoring_TagBound(iMarker_Monitoring);
+          auto Marker_Tag = config->GetMarker_All_TagBound(iMarker);
+          if (Marker_Tag == Monitoring_Tag)
+            Surface_Buffet_Metric[iMarker_Monitoring] = Buffet_Metric[iMarker];
         }
 
       }