Hello everyone,
im currently trying to perform a simulation of a Hydrogen/Air supersonic combustion in a RadicalFraming scramjet using Fluent with the density based solver and AUSM, im using a Chemkin mechanism with 7 species with thermo data and transport data files.turbulence model is k omega SST.

my problem is when i choose the Eddy dissipation concept with CHEMKIN CFD SOLVER the flow equations are solved properly and the pressure distribution is good, but the kinetic rate of reaction stays at 0 kgmol/m3 s. and there is no flame formation . what could be the problem ?

is it the mechanism or the transport data ?

or could it be something else ? 

When i use the stiff chemistry solver it works fine and and im able to get a flame and formation of radicals.

Thank you