[Mihir]

I am trying to make a solver for binary species. I need to add enthalpy diffusion terms in the energy equation. I am using rhoSimpleFoam. Energy equation for rhoSimpleFoam is

volScalarField& he = thermo.he();
  
  fvScalarMatrix EEqn
  (
      fvm::ddt(rho, he) + fvm::div(phi, he)
    + fvc::ddt(rho, K) + fvc::div(phi, K)
    + (
          he.name() == "e"
        ? fvc::div
          (
              fvc::absolute(phi/fvc::interpolate(rho), U),
              p,
              "div(phiv,p)"
          )
        : -dpdt
      )
    - fvm::laplacian(turbulence->alphaEff(), he)
   ==
      fvOptions(rho, he)
  );

I need to these extra terms in the energy equation.

Ca, Cb are the mass fraction of the two species. Dab is the ordinary diffusion while DT is the thermal diffusion coefficient. Cao is the initial mass fraction of specie A. I have already added specie transport equation and the solver is working but could not figure out how to add these terms.