Problem using EDM for combustion

nakul · May 30, 2011, 06:39

Hi,

I am trying to simulate combustion in a cylindrical pipe using Eddy Dissipation Model of FLUENT. At the inlet and outlet of the pipe I have made "far-field" domains as the flow around the inlet and outlet is also important.

The boundaries of "far-field" are assigned "pressure far-field" BC with ambient pressure and temperature and zero velocity.

In this setup, I am not being able to initiate combustion. I have solved the flow-field (cold flow analysis) but when I switch on the reaction, no product formation occurs.

I am simulating a completely unsteady problem. I think there is some problem with EDM setup as I got acceptable flow-field from cold flow simulation.

Please Help.

Nakul

aulu · August 11, 2011, 06:01

Hallo.

I have got a question concerning the eddy-dissipation model. I have read that it's possible to modell 2-step-reactions with this modell. But if I look for the mass fraction of the product of the second reaction it's always 0. For the mixing rate I used the default values for both reactions. Is it right? I also tried other ones (A=0.1, B=-1), but the mass fraction is still 0.

Thanks in advance.

May 30, 2011, 06:39	Problem using EDM for combustion	#1
nakul Senior Member Nakul Join Date: Apr 2010 Location: India Posts: 147 Rep Power: 16	Hi, I am trying to simulate combustion in a cylindrical pipe using Eddy Dissipation Model of FLUENT. At the inlet and outlet of the pipe I have made "far-field" domains as the flow around the inlet and outlet is also important. The boundaries of "far-field" are assigned "pressure far-field" BC with ambient pressure and temperature and zero velocity. In this setup, I am not being able to initiate combustion. I have solved the flow-field (cold flow analysis) but when I switch on the reaction, no product formation occurs. I am simulating a completely unsteady problem. I think there is some problem with EDM setup as I got acceptable flow-field from cold flow simulation. Please Help. Nakul

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August 11, 2011, 06:01		#2
aulu New Member Join Date: Aug 2011 Posts: 3 Rep Power: 15	Hallo. I have got a question concerning the eddy-dissipation model. I have read that it's possible to modell 2-step-reactions with this modell. But if I look for the mass fraction of the product of the second reaction it's always 0. For the mixing rate I used the default values for both reactions. Is it right? I also tried other ones (A=0.1, B=-1), but the mass fraction is still 0. Thanks in advance.