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How to express the difference in temperature between two elements? (Lumped radiation)
Posted 25 giu 2012, 09:59 GMT-4 Heat Transfer & Phase Change, Materials, Mesh, Parameters, Variables, & Functions Version 4.2a 1 Reply
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Hello dear colleagues,
I am modeling heat transfer in a porous packed bed and I want to avoid T^4 terms (numerical stability), so, I want to model radiation in a simple way. The idea is to either lump radiation into conduction or make a simple source term for it.
The latter option would yield something like:
Radiation heat transferred = Boltzmann_constant * emissivity * surface_between_elements * average_temperature * (temperature_element_1-temperature_element_2)
OR: Q_rad = sigma * epsilon * T_av^3 * (T_1 - T_0)
But for this I need the temperature of the neighboring elements. How do I call those? Is there a better way to describe this idea? Is there a way to properly describe this using dT/dx (like conduction) ?
Thanks for any suggestions. Kind regards,
Ray
1 Reply Last Post 26 giu 2012, 04:04 GMT-4