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Radiation Model: Discrete Ordinate method

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Old   August 1, 2010, 02:04
Question Radiation Model: Discrete Ordinate method
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rabbahs
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Dear All,

I am trying to model combustion in a reactor. The geometry is 2D-axi symmetric, composed of a rectangle having an inlet and out let. From inlet the coal particles (via injector) along with oxygen is coming, after combustion mixture of CO2, CO and other gases leave the reactor.

From short side of the rectangle there is a heat flux is coming into the reactor which is supposed to be absorbed by coal, refractory wall of reactor and gases.

Now, when I select the Discrete ordinate method for radiation Heat transfer in Fluent. It always ask Absorption coefficient, Scattering coefficient and reflective index for all solid and fluid material type in MATERIAL panel.

So, Specifically my questions are,

1) for each gas phase (CO2, CO, H2, H2S and other gas species) where I can find the absorption coefficient, scattering coefficient and reflective index ? Is there some sort of data base available ? Please keep this in mind that the temperature and pressure of the mixture of gas will change during combustion.

2) For solid species ( coal particle and Re-factory wall of reactor) where I can I find the absorption, scattering coefficient and reflective index. Or the value of these coefficients are zero, as these material are opaque ?


This is really very confusing, because in all my heat transfer studies I only learn about emissivity, transmittance, reflectivity, absorptivity etc.

I will be glad that any one can answers my question.



Thanks
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Old   March 2, 2014, 22:55
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Muhammad Uwais Zuraidi
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hi shabbarraza2000

did you manage to find the coefficients?
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Old   March 3, 2014, 01:04
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New fluent version provides the absorption coefficient for most of the species. I am using fluent 14. let me know.
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Old   April 11, 2014, 21:48
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Quote:
Originally Posted by Muhammed_iraq View Post
Hi all
Please i need tutorial or example by FLUENT for parabolic solar collector
Thanks
Dear Bro,
I am unsure that you can find some specific example for your case. but try to start the 3D version of fluent and do some baseline work to match your results with analytical calculation.
Thanks
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absorption coefficient, discrete ordinate model, radiation, refective index, scattering coefficient

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