[ChenZhan]

hello everyone!
i have a problem about how to correctly set the parameters of the radiation to ensure the accurity of the computation with the fluent.Now, i want to simulate a combution of methane and air mixture(premixed combustion).
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o o o o o o o o o o o o o o o o o o o o o
o o o o o o o o o o o o o o o o o o o o o
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(it is a diagram of my simulation geometry model.The left side is a velocity inlet,and the right side is outflow boundary condition.The letter of "o" represents the solid ball,the top side is the outerwall).
Who can give me some suggustion on how to chose a radiation model in my case, and tell me which handbook include some information on the solid material radiation parameters which i can use in the fluent,for example,absorption coefficient,refractive index and so on.Especially wish you can tell me how to set the boundary condition of radiation,for instance,internal emissivity.
Good luck,eveybody!
Wish your help.
Email:chenzhana@163.com

[wwa]

Hello Chenzhan,
in your case you can try DO radiation model. For better accuracy, increase the angular discretization for theta and phi (e.g. 6 for division and 3 for pixels).
If you don't know the emissivities of the surfaces, try several of them to see the effect on your computation.
And for the literature, you may start with references in fluent user's guide...

regards,

Peter