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-   -   premixed combustion using Zimont model (http://www.cfd-online.com/Forums/fluent/33666-premixed-combustion-using-zimont-model.html)

 bob May 7, 2004 10:19

premixed combustion using Zimont model

Hi Is somebody has done some premixed combustion simulations using zimont I want to discuss some issues. Please respond. Bob

 Tom May 7, 2004 10:29

Re: premixed combustion using Zimont model

I have used this model for methane-air combustion. It works well.

 bob May 7, 2004 11:24

Re: premixed combustion using Zimont model

Thanks I have some simple questions.

I started simulating the propane-air combustion using Zimnot model and adiabatic.

During starting of the simulation residual was decresing and then suddenly it started to increase do you know th reason or help me.

Also how can I dcribe outflow boundary condition for progress variable is it specified in pressure outlet boundary condition where back flow progress variable is taken to be 1.0.

Also what is the best way do simulations first compute the steady using non-reactive flows and then start the combustion calculation.

 Tom May 7, 2004 11:47

Re: premixed combustion using Zimont model

1. If you post your e-mail address I can send you some information that may help.

2. What residuals started to increase. This could be for many reasons, for example, grid quality, how you initialized the solution, under relaxation factors etc...

3. For your outlet condition you can either use Pressure Outlet or Outflow. Pressure Outlet may be more stable and in a combustion simulation which is never easy may give better stability. The progress variable states that if the mixture is burnt then c=1, therefore at the outlet where you would expect this the backflow value should be set to 1.

4. This is up to you and depends on the complexity of the flow field. In general you should start with a isothermal model and build up. I have used this model with combustion form the start and patched a fluid region to iginite the mixture.

Hope this helps Tom

 bob May 7, 2004 12:33

Re: premixed combustion using Zimont model

Thanks it works fine when you have non-adiabatic combustion when you have adiabatic combustion it is giving me a problem.

By the way how to specify equaivalence ratio of the mixture let us say I want to simulate lean premix so Equivalence ratio=0.6. Thanks for your response bob

 bob May 10, 2004 01:49

Re: premixed combustion using Zimont model

Hi tom I am expecting answers for this question I hope you know the answer. Bye Bob By the way you can send me the helpful document in

bob_00_bob2001@yahoo.com

Thanks for your help Bye bob

 Tom May 10, 2004 05:48

Re: premixed combustion using Zimont model

Hope it helps.

 HeKhalil November 22, 2012 06:50

How to specify equivalence ratio in premixed combustion model?

Hey guys, i have the same problem of not knowing how to specify the equivalence ratio in the premixed combustion model either in adiabatic or non-adiabatic case?

 Howard March 19, 2015 06:04

Quote:
 Originally Posted by bob ;112380 Hi Is somebody has done some premixed combustion simulations using zimont I want to discuss some issues. Please respond. Bob
Hello, I'm a new user of OpenFoam. Could I ask how to use this zimont model? In XiFoam or reactiongFoam? Could you give me some information

 ngothientu August 16, 2015 06:03

Hi Tom,
Can you help me that If I want to simulation LPG (60%Propane, 40% Butane) with air Premixed combustion in Fluent. How can I set it??? My email: ngothientu_tn@yahoo.com.vn.
Thank you so much

 Purushottam More October 21, 2015 13:07

premixed flame

HI,
I am a newer in premixed combustion. When I use the FLUENT to modeling, I am confusing about the premixed combustion using Zimont with G-equation model in FLUENT. I can't find where can I specify the mixture(methane-air) equivalence ratio or about the mixture materials.