Learning Forum

[vashista]

Hii all,

I am modeling supersonic flows with the effect of reaction. i am using steady laminar non-premixed flamelet model to model combustion. i use 9 species 19 step reaction for hydrogen-air mixture. within the combustor i want to identify the burnt and unburnt mixture of hydrogen. can we do this by using progess variable. if so how do we do it.

i thabk readers for their valuable suggestions

[DrAmine]

Here you need to use the partially-premixed model.

[vashista]

Thank you for your kind reply.

how do we identify the burnt/ unburt fuel in the case of non premixed model.

in my geometry air is injected at x=0.0 mm and hydrogen is injected at 67.00 mm in the stream wise direction. and the combustion begings after 67.00 mm

[DrAmine]

You cannot identify burnt and unburnt regions in Non-Premxied apporach as there is no flame front acting as surface discontinuity between burnt and unburnt regions.

[vashista]

ok thank you for your kind reply. i will consider your suggestion. I wanted to calculate combustion efficiency, which is nothing but the rate of consumption of hydrogen as indicated in the literature. In order to calculate this, I have found out the ratio of the difference in mass flow rate of hydrogen from fuel inlet and at any particular streamwise direction to that of the mass flow rate of hydrogen at the fuel inlet I.e (). In my geometry combustion is getting completed within the combustor itself so the entire hydrogen is getting consumed which means efficiency is 100%. I want to know if this result is correct or not.

Thank you