Reaction rate too slow

drb764 · March 30, 2011, 12:48

Hello.

I try to simulate combustion in a porous structure using eddy dissipation model. Convergence is okay, but the reaction rate is too small. The combusion should be (nearly) completed at the burner outlet, but the ch4 mass fraction is only half the inlet value. Is there a way to speed up the reaction?

THANK YOU A LOT IN ADVANCE!

joey2007 · April 6, 2011, 14:49

Standard values are adjusted to standard cases without porous media. Increase EDM A and EDM B, will increase reaction rate.

drb764 · April 6, 2011, 14:51

thank you joey!

riccia · September 16, 2011, 08:44

Hi,

I am also trying to simulate reactions in porous medium but i do not get even half conversion of species.

I cannot find anything on the internet about mixing rates and how to change them logically.

I would be glad if you could give me some insights.

Thank you,
Mehtap

March 30, 2011, 12:48	Reaction rate too slow	#1
drb764 New Member K. D. Join Date: Feb 2011 Posts: 6 Rep Power: 15	Hello. I try to simulate combustion in a porous structure using eddy dissipation model. Convergence is okay, but the reaction rate is too small. The combusion should be (nearly) completed at the burner outlet, but the ch4 mass fraction is only half the inlet value. Is there a way to speed up the reaction? THANK YOU A LOT IN ADVANCE!

April 6, 2011, 14:49		#2
joey2007 Senior Member Join Date: Mar 2009 Location: Europe Posts: 169 Rep Power: 17	Standard values are adjusted to standard cases without porous media. Increase EDM A and EDM B, will increase reaction rate. __________________ - - - - - ------------------------------------------------------------------------ Please do not forget: I am not paid for answering your questions. Thousands of issues can cause a division by zero. Please do not capture a thread, with the argument: "I have the same issue ...."

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April 6, 2011, 14:51		#3
drb764 New Member K. D. Join Date: Feb 2011 Posts: 6 Rep Power: 15	thank you joey!

September 16, 2011, 08:44		#4
riccia New Member m Join Date: May 2011 Posts: 6 Rep Power: 15	Hi, I am also trying to simulate reactions in porous medium but i do not get even half conversion of species. I cannot find anything on the internet about mixing rates and how to change them logically. I would be glad if you could give me some insights. Thank you, Mehtap