FIX: Prevent zero-division in Cp calculation for zero free-stream velocity

Author: ayush4874

SU2_CFD/src/output/CFlowCompOutput.cpp

@@ -336,7 +336,11 @@ void CFlowCompOutput::LoadVolumeData(CConfig *config, CGeometry *geometry, CSolv
   SetVolumeOutputValue("MACH", iPoint, sqrt(Node_Flow->GetVelocity2(iPoint))/Node_Flow->GetSoundSpeed(iPoint));
 
   const su2double factor = solver[FLOW_SOL]->GetReferenceDynamicPressure();
-  SetVolumeOutputValue("PRESSURE_COEFF", iPoint, (Node_Flow->GetPressure(iPoint) - solver[FLOW_SOL]->GetPressure_Inf())/factor);
+      if (std::abs(factor) > 1e-10) {
+        SetVolumeOutputValue("PRESSURE_COEFF", iPoint, (Node_Flow->GetPressure(iPoint) - solver[FLOW_SOL]->GetPressure_Inf())/factor);
+      } else {
+        SetVolumeOutputValue("PRESSURE_COEFF", iPoint, 0.0);
+      }
   SetVolumeOutputValue("VELOCITY-X", iPoint, Node_Flow->GetVelocity(iPoint, 0));
   SetVolumeOutputValue("VELOCITY-Y", iPoint, Node_Flow->GetVelocity(iPoint, 1));
   if (nDim == 3){

SU2_CFD/src/output/CFlowIncOutput.cpp

@@ -416,7 +416,11 @@ void CFlowIncOutput::LoadVolumeData(CConfig *config, CGeometry *geometry, CSolve
   }
 
   const su2double factor = solver[FLOW_SOL]->GetReferenceDynamicPressure();
-  SetVolumeOutputValue("PRESSURE_COEFF", iPoint, (Node_Flow->GetPressure(iPoint) - solver[FLOW_SOL]->GetPressure_Inf())/factor);
+  if (std::abs(factor) > 1e-10) {
+    SetVolumeOutputValue("PRESSURE_COEFF", iPoint, (Node_Flow->GetPressure(iPoint) - solver[FLOW_SOL]->GetPressure_Inf())/factor);
+  } else {
+    SetVolumeOutputValue("PRESSURE_COEFF", iPoint, 0.0);
+  }
   SetVolumeOutputValue("DENSITY", iPoint, Node_Flow->GetDensity(iPoint));
 
   if (config->GetKind_Solver() == MAIN_SOLVER::INC_RANS || config->GetKind_Solver() == MAIN_SOLVER::INC_NAVIER_STOKES){

SU2_CFD/src/output/CNEMOCompOutput.cpp

@@ -346,7 +346,12 @@ void CNEMOCompOutput::LoadVolumeData(CConfig *config, CGeometry *geometry, CSolv
   SetVolumeOutputValue("MACH", iPoint, sqrt(Node_Flow->GetVelocity2(iPoint))/Node_Flow->GetSoundSpeed(iPoint));
 
   const su2double factor = solver[FLOW_SOL]->GetReferenceDynamicPressure();
-  SetVolumeOutputValue("PRESSURE_COEFF", iPoint, (Node_Flow->GetPressure(iPoint) - solver[FLOW_SOL]->GetPressure_Inf())/factor);
+  
+  if (std::abs(factor) > 1e-10) {
+    SetVolumeOutputValue("PRESSURE_COEFF", iPoint, (Node_Flow->GetPressure(iPoint) - solver[FLOW_SOL]->GetPressure_Inf())/factor);
+  } else {
+    SetVolumeOutputValue("PRESSURE_COEFF", iPoint, 0.0);
+  }
 
   if (config->GetViscous()){
     SetVolumeOutputValue("LAMINAR_VISCOSITY", iPoint, Node_Flow->GetLaminarViscosity(iPoint));