???Flame extinct (Methane-Air)

April 24, 2001, 22:18

Dear Mr. or Mrs:

I'm modeling premixed laminar combustion for methane/air.

I meet a great difficulty --> At the beginning of iteration, I set the Cp as constant(1000J/kg.k), then the flame front is basically formed as the iteration proceeds. But the temperature of the flame is too higher than 3000k. So in order to reduce the flame temperature to the reasonable level, I set the Cp as "Mixing Law", but the flame will be extinct soon after I set the Cp as "Mixing Law".

Can you tell me why?

Thank you. Sincerely yours, Harry.

April 25, 2001, 10:34

In addition to using the "mixing law" for the methane-air mixture, I suggest you verify the specific heat for each specie in the flowfield is defined using the piecewise-polynomial option.

April 26, 2001, 09:32

Hi,Steven:

Thank you for you reply. I do have set the specific heat for each specie in the flowfield as piecewise-polynomial(by default value). do you have any other suggestions? Thank you.

Sincerely yours, Harry.

April 24, 2001, 22:18	???Flame extinct (Methane-Air)	#1
Harry Qiu Guest Posts: n/a	Dear Mr. or Mrs: I'm modeling premixed laminar combustion for methane/air. I meet a great difficulty --> At the beginning of iteration, I set the Cp as constant(1000J/kg.k), then the flame front is basically formed as the iteration proceeds. But the temperature of the flame is too higher than 3000k. So in order to reduce the flame temperature to the reasonable level, I set the Cp as "Mixing Law", but the flame will be extinct soon after I set the Cp as "Mixing Law". Can you tell me why? Thank you. Sincerely yours, Harry.

April 25, 2001, 10:34	Re: ???Flame extinct (Methane-Air)	#2
Steven Smith Guest Posts: n/a	In addition to using the "mixing law" for the methane-air mixture, I suggest you verify the specific heat for each specie in the flowfield is defined using the piecewise-polynomial option.

April 26, 2001, 09:32	Re: ???Flame extinct (Methane-Air)	#3
Harry Qiu Guest Posts: n/a	Hi,Steven: Thank you for you reply. I do have set the specific heat for each specie in the flowfield as piecewise-polynomial(by default value). do you have any other suggestions? Thank you. Sincerely yours, Harry.

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