Flexible setup of flamelet boundary conditions

[bigfooted]

Proposed Changes

Give a brief overview of your contribution here in a few sentences.

Enthalpy boundary conditions for the flamelet equation can now be set to use either the BC's coming from the flow solver (defined in terms of temperature) or the species BC's
This was a bit confusing before because we did a mix of both.

We now have

FLAMELET_ENTHALPY_BC=FLOW_MARKERS
FLAMELET_ENTHALPY_BC=SPECIES_MARKERS

To either use temperature or heat flux from the flow solver (MARKER_INLET, MARKER_ISOTHERMAL/MARKER_HEATFLUX) , or use enthalpy directly from the species solver (MARKER_INLET_SPECIES, MARKER_WALL_SPECIES).

There will be a tutorial + regression coupled to this.

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[joshkellyjak]

If this is also intended to impact inlet bc's do you also have to modify the inlet implementation in CSpeciesFlameletSolver also? The enthalpy here is calculated from temperature and PV which regardless of whether species or flow is selected in this option?

void CSpeciesFlameletSolver::BC_Inlet(CGeometry* geometry, CSolver** solver_container, CNumerics* conv_numerics,
                                      CNumerics* visc_numerics, CConfig* config, unsigned short val_marker) {
  SU2_ZONE_SCOPED
  string Marker_Tag = config->GetMarker_All_TagBound(val_marker);

  su2double temp_inlet = config->GetInletTtotal(Marker_Tag);

  /*--- We compute inlet enthalpy from the temperature and progress variable. ---*/
  su2double enth_inlet;
  GetEnthFromTemp(solver_container[FLOW_SOL]->GetFluidModel(), temp_inlet, config->GetInlet_SpeciesVal(Marker_Tag),
                  &enth_inlet);
  SU2_OMP_FOR_STAT(OMP_MIN_SIZE)
  for (auto iVertex = 0u; iVertex < geometry->nVertex[val_marker]; iVertex++) {
    Inlet_SpeciesVars[val_marker][iVertex][I_ENTH] = enth_inlet;
  }
  END_SU2_OMP_FOR

  /*--- Call the general inlet boundary condition implementation. ---*/
  CSpeciesSolver::BC_Inlet(geometry, solver_container, conv_numerics, visc_numerics, config, val_marker);
}

Here the enthalpy is overwritten regardless of whether you specify flow or species markers.

[bigfooted]

Hi @joshkellyjak! Yes, you are right, I forgot to update this routine. I have added it to the PR.

[pcarruscag]

What is the difference between FLAME and FLAMELET?

[bigfooted]

We were quite sloppy in the past in the use of FLAME vs FLAMELET.
Flamelet is (should be) a specific model, flame is (should be) a physics concept that works for more than the flamelet model. so FLAME_INIT_METHOD should also initialize for instance the detailed chemistry model. FLAMELET_ENTHALPY_BC should only work for the flamelet model. We can already anticipate that we would like FLAMELET_ENTHALPY_BC to work for detailed chemistry and call it FLAME_ENTHALPY_BC. Should I rename it FLAME_ENTHALPY_MODEL?

[pcarruscag]

It it can be consistent I think it should.