[ex-bmx]

I am doing the simulation of non-premixed combustion, the gas that enters is gasified biomass, and this by having contact with the secondary air, but it handles well on several variables such as income fluent the molecular content of each fluid, but in the conditions I have boundary issues, I want to perform this simulation using the LES method, attached a picture for better understanding of the problem, I hope your help Thanks

You think I have problems with the geometry gambit because I believe "internal default" when extrude the face, not a problem or if there should be 3d geometry