adding explanation enthalpy as passive scalar and updating zimont pywrapper

Author: Cristopher-Morales

SU2_CFD/src/fluid/CFluidFlamelet.cpp

@@ -118,6 +118,13 @@ CFluidFlamelet::~CFluidFlamelet() {
 }
 
 void CFluidFlamelet::SetTDState_h(su2double val_enthalpy, const su2double* val_scalars) {
+  /*--- For the fluid flamelet model, the enthalpy (and the temperature) are passive scalars.
+  val_scalars contains the enthalpy as the second variable: val_scalars= (Progress_variable, enthalpy,..).
+  Consequently, the energy equation is not solved when the fluid flamelet model is used, instead the energy equation for
+  enthalpy is solved in the species flamelet solver, and the enthalpy solution is overwritten in the CIncEulerSolver.
+  Likewise, The temperature is retrieved from the look up table. Then, the thermodynamics state is fully determined with
+  the val_scalars. This is the reason why enthalpy (or temperature) can be passed in either SetTDSTtate_T or
+  SetTDState_h without affecting the solution.---*/
   SetTDState_T(val_enthalpy, val_scalars);
 }
 

TestCases/py_wrapper/turbulent_premixed_psi/run.py

@@ -95,8 +95,14 @@ def update_temperature(SU2Driver, iPoint):
     iFLOWSOLVER = SU2Driver.GetSolverIndices()['INC.FLOW']
     # the list with names
     solindex = getsolvar(SU2Driver)
+    primindex = SU2Driver.GetPrimitiveIndices()
+    # get Cp
+    iCp = primindex.get("CP_TOTAL")
+    Cp = SU2Driver.Primitives()(iPoint,iCp)
+    # get solution index for energy equation
     iTEMP = solindex.get("TEMPERATURE")
-    SU2Driver.Solution(iFLOWSOLVER).Set(iPoint,iTEMP,T)
+    # set enthalpy, for Ideal Gas model, enthalpy is Cp*T
+    SU2Driver.Solution(iFLOWSOLVER).Set(iPoint,iTEMP,Cp*T)
 
 
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