Serach for mixture fraction codes
 

Hello, everyone, I am a beginer at combustion simulation. Now I want to find some tutorial codes about mixture fraction. Could you tell me where I can find it (it is better to be written by c langurage ). Thanks a lot!

Re: Serach for mixture fraction codes
 

Can you elaborate? Do you want to solve for chemical equilibrium in exhaust gasses?

Re: Serach for mixture fraction codes
 

Hi, Dear Steve, First thanks for your response. I have written a c program for mixture fraction. But I found that there are some errors in the advection-diffusiong equation of the mixture fraction.The main error is that the flame length is too long. Until now I can not find the reason. So I want to see other's program to debug my program. The reaction in my program bases on single step reaction.

Re: Serach for mixture fraction codes
 

Hi, Dear Steve, First thanks for your response. I have written a c program for mixture fraction. But I found that there are some errors in the advection-diffusiong equation of the mixture fraction.The main error is that the flame length is too long. Until now I can not find the reason. So I want to see other's program to debug my program. The reaction in my program bases on single step reaction. So I want to find a diffusion flame codes including mixture fraction evolving.

Re: Serach for mixture fraction codes
 

The use of single-step kinetics may be a problem. Unless you do something ad hoc such as reduce the heat released per mole of fuel to account for the fact that products contain radicals, the post-flame temperature will be too high. Also, a global reaction rate generally is valid over a very limited range of conditions. What have you done to make sure your problem is the advection-diffusion equation and not something else, such as simplistic physical models?

Re: Serach for mixture fraction codes
 

Talking about that, I have written too a Matlab program simulating a diffusion flame. But I have employed MacCormack's algorithm. It does not work nowadays, but do you think it is not appropiate for these equations?

Re: Serach for mixture fraction codes
 

Hi,everyone, Thanks for your responses. I have written a program for diffusion flame with mixture fraction. There is a problem that the mixture fraction will diffuse to the whole domain. So the flame length is too longer than the analytic solutions got by Ropper(Roper, F. G, The prediction of laminar jet diffusion flame sizes,Combustion and Flame, 29, 219-234 (1977)). Thus I want to find a correct codes to check my program. Because now my purpose is not simulating actual diffusion flame, the single step reaction is enough for my program. And the mixture fraction is governed by a advection-diffusion equation. Could you help me? Thanks a lot. Kind regard, Sheng Chen