combustion efficiency

aravind vashista · November 20, 2018, 02:26

Hii,
I am modeling a a flow involving supersonic flows with the effects of combustion. my fuel is hydrogen and air is oxidizer. i use laminar flamelet model to model reacting flows. the calculation is complete. i want to find out combustion efficiency which is (1-mass flow rate of hydrogen/ unburnt hydrogen mass flow rate). I simply get the mass flow rate of hydrogen burnt / consumed by integrating (density*Yhydrogen*V*A) (Y_hydrogen at a given streamwise location) along the leangth of the combustor. But how do i find out the unburnt hydrogen mass fraction present along the combustor length.

I thank readers for their valuable suggestions.

LuckyTran · November 20, 2018, 10:46

Don't you have a progress variable in this model? The progress variable helps you distinguish between burnt/unburnt.

aravind vashista · November 21, 2018, 03:28

Quote:

Originally Posted by LuckyTran

Don't you have a progress variable in this model? The progress variable helps you distinguish between burnt/unburnt.

i use non-premixed laminar steady flamelet model. I dont know about progress variable, and how to set values for it

November 20, 2018, 02:26	combustion efficiency	#1
aravind vashista Member ARAVIND SRIDHARA Join Date: Jan 2017 Posts: 32 Rep Power: 9	Hii, I am modeling a a flow involving supersonic flows with the effects of combustion. my fuel is hydrogen and air is oxidizer. i use laminar flamelet model to model reacting flows. the calculation is complete. i want to find out combustion efficiency which is (1-mass flow rate of hydrogen/ unburnt hydrogen mass flow rate). I simply get the mass flow rate of hydrogen burnt / consumed by integrating (densityYhydrogenV*A) (Y_hydrogen at a given streamwise location) along the leangth of the combustor. But how do i find out the unburnt hydrogen mass fraction present along the combustor length. I thank readers for their valuable suggestions.

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November 20, 2018, 10:46		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,761 Rep Power: 66	Don't you have a progress variable in this model? The progress variable helps you distinguish between burnt/unburnt.