Learning Forum

[Zoelle Wong]

Dear ANSYS Forum Team,

I'm confused how the radiation heat transfer rate is calculated in FLUENT. I know there's a way to see the heat transfer rate by going to: flux reports >> Total Heat Transfer Rate >> select boundaries >>  results.

I'm trying to validate my results using the following equation:

where sigma is the Stephan-Boltzman constant, epsilon the internal emissivity (in this case I have prescribed as 1 for black-body), A the area of the surface, and T, the weighted average Temperature.  

The boundaries' areas and temperatures are taken from: reports >> surface integrals, which I have also double checked by hand. 

Is the equation above the same method that FLUENT is calculating the radiation heat transfer rate? I saw in the manuals that Q_rad can be computed differently between a fluid-fluid, or solid-fluid interface. In my case, I have a fluid-solid interface where the fluid is much hotter than the surface. My model is also using the P1 radiation module. 

 

Thanks!!

 

[Nilay Pedram]

Hello,
Please refer to Fluent's User Guide - 5.3.3. P-1 Radiation Model Theory (ansys.com)
If you are not able to access the link, refer to this forum discussion: How to access the ANSYS Online Help
Thanks!