Hydrogen combustion with swirl of coaxial air
 

I have been modelling hydrogen-air supersonic combustion..The axial position of maximum temperature is supposed to be closer to the burner exit by imparting swirl.But Iam observing it to be more distant after convergence of the solution.Can anyone explain what could be the reason? Iam using RNG k-e turbulence model and eddy dissipation reaction model.