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Heat Flux and Radiation at same boundary

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Old   March 11, 2015, 15:20
Default Heat Flux and Radiation at same boundary
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Mario Arias
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Hello,

I am trying to model a heat flux boundary condition on a surface, and would like to allow it to radiate into a vacuum. Is P-1 the correct radiation module?And if so, Do i just change the emissivity to a gray body where i want it to radiate, and 0 to any i want shielded in the boundary conditions?

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Mario Arias
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Old   March 12, 2015, 09:56
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Paritosh Vasava
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I did not understand what you mean by 'shielded'. Anyways with P1-model you will only have emissivity (for radiations) in the boundary setup. 'External Emissivity' for walls and 'Internal emissivity' for walls shared by the interfaces.

The choice of model would depend upon optical thickness. P-1 is good for optical thickness larger than 1. DO and DTRM do not have any such limitations and are more widely applicable. Also with DO you will have more choices over boundary conditions as you can also have semi-transparent material (e.g. glass) in the simulation.

P.S: I too have started learning about radiation since last week. My answer is based on my very brief experience with simulating radiations with fluent.
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Old   March 13, 2015, 05:47
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Mario Arias
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All I have is a square microchannel heat exchanger. I am set a heat flux boundary condition on a single wall of that heat exchanger, and I would like to let it radiate to a vacuum.
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fluent parallel memory, heat flux, p-1, radiation, radiation flux

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