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Radiation Properties of MultiComponents

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Old   April 30, 2013, 14:43
Default Radiation Properties of MultiComponents
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Hello!

I write to ask about the configuration of the radiation properties of a reactive mixture. I'm modeling internal flow combustion in a boiler, after selecting the turbulence model and define the emissivity of the walls, the program gives me this warning:

"In Analysis 'Flow Analysis 1' - Domain 'Default Domain': Radiation properties for the Mixtures 'reaction mixture' will be based on a mass weighted average of the constitutive components, Unless overridden with explicit Mixture Property settings."

Reading the CFX help I found that by default the program calculates the radiation properties through a weighted sum of its components, which computationally is not recommended (my simulation has 10 components).

I wonder who could give me recommendation to avoid this problem, or how to calculate these properties.

Greetings.
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Old   April 30, 2013, 19:39
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Glenn Horrocks
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Unless you have a better model of what the mixture properties are then why not just accept the default?
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Old   May 1, 2013, 22:19
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Erik
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Right, I don't see why that would make it that much more computationally expensive. taking the average of 10 values is not hard far a computer to do considering all the other calculations its performing.
It has to do this for every other material property anyways, so whats the big deal?
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Old   May 27, 2013, 11:35
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Ok.

I thought these calculations represented a high computational cost.

Greetings!!!
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