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Victor May 7, 2007 13:13

abnormally high flame temperatures in C2H2/Air com
 
What might be the reason for C2H2/air flame temperature being too high (over 3300 K). I am using 1 global reaction mechanism with eddy-dissip/finite rate model. Adiabatic flame temperature for this mixture should be 1000K lower. Also, CO and H2O do not converge. The geomery and the physics of the problem are very simple.


Allan Walsh May 7, 2007 16:25

Re: abnormally high flame temperatures in C2H2/Air
 
Heat capacity of gases not set to be a function of temperature?

Victor May 7, 2007 16:47

Re: abnormally high flame temperatures in C2H2/Air
 
Thank you !

Phil May 7, 2007 18:00

Re: abnormally high flame temperatures in C2H2/Air
 
These basic models normally over predict the flame temp.

Non-smooth transitions between coarse and dense mesh regions, or highly skewed elements are the usual reasons for poor convergence - OR NON-REALISTIC PHYSICS STRUGGLING TO SATISFY THE FUNDAMENTAL EQUATIONS. This is usually caused by getting the boundary conditions wrong or adding walls you don't notice.


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