Catalytic partial oxidation

Fonzy

I want to model CPO interactions with the flow with Fluent without enabling reactions, only species transport. I have a solid area, adjacent to a mixture gas-phase. I have reactions in the gas phase, but also catalytic reaction on the solid surface.

This way, I intend to model everything related to reactions by myself, like species production rate in the gas phase, with UDF. But I should model other production rates/fluxes, I suppose.

1°) gas phase species production rate: ok, no pb. I have the kinetics.

2°) gas phase energy production rate (due to chemical reaction): Do I have to model it? Is the energy equation taking standard formation enthalpies in account (so it shouldn't be necessary) or no? ... I suppose it isn't according to UG chapter 11, so I'd have to explicit it.

3°) surface species production rate: There, I suppose it would be better to compute the species diffusion flux at the wall (non-zero due to catalytic reaction). I have closure equations to compute them all (I linked species production rate and time-dependent surfacic mass fraction of adsorbed species)

4°) surface energy production rate:that's the big problem for me. If I make the balance, I find out that heat flux is not continue due to surface heat release after catalytic reactions. Problem is: I don't see this value in Fluent. There's a heat production rate for a wall, but in W/m3 whereas it should be in W/m2 (same dimension as a flux). Other problem (linked to 2°): must I explicit this energy production rate or is it implicitly taken in account in solid/fluid energy equation?

Thank you for reading this long post. I know this problem can be time-consuming, but if you have already in your knowledge some direct explanations, it would be great.

Thanks in advance.