Hi, everyone, First thanks for your help! I am a beginer at combustion simulating. Now I am plan to simulate a laminar diffusion flame(methane-air and propane-air ). But I do not know how to get the temperature from the mixture fraction. I hear that the corresponding relationship between the mixture fraction and the temperature can be got by some existed program codes. Could you tell me where I can find such codes and references? Thanks a lot!

The temperature is found from r*E=r*h(T,Y_i) -P(r,T,Y_i) + 0.5*r* V^2. Once you know the total total Energy r*E, the mass fraction Y_i, density r, and volocity V, you can compute T implicitly by a iteration scheme such as Newton method from above Eq, or by interpolation from a tabulated h_i ---- T data. The later needs a small code. The known quantities above are from flowfield solution.

Hi,

You can try to simulate laminar combustion be resolving the full reactive system as explained by versi: solve energy and species.

From the mention of mixture fraction, I believe you aim at resolving for a passive scalar and from that deduce temperature T and mass fractions Yk. There is two way you can relate mixture fraction and (T, Yk):

1) equilibrium asumption: from Z deduce enthalpy and Yk at the unreactive state; then compute the chemical equilibrium to obtain the final Yk, enthalpy and temperature

2) flamelet asumption: compute a flamelet (counter-flow?) based on your condition. The flamelet will then provide the relation Z -> (T,Yk)

Where to find such codes? a) if you are surrounded by people who know chemkin, they may have the tools to do equilibrium and/or flamelet

b) if not, there is a "improved" (or is it a remake) of chemkin known as Cantera http://rayleigh.cds.caltech.edu/~goo...era/index.html

Hoppe being helpfull. Julien