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Alex April 12, 2005 19:53

radiation on interfaces
 
Hello!!

I have to put a thermal radiation boundary condition (emissivity)on an interface between a solid domain and a fluid domain (air: non partecipating media). Have I to put same value of emissivity for both sides of the interface? Can I set an emiss=0 for the air side and an emiss=0.98 for the solid side of the interface? Am I rigth or this setting will give some problems?

Last question : when should I use "conservative interface flux" for a fluid-solid interface?

I use the monte carlo model

Thank you all for the help

Glenn Horrocks April 13, 2005 18:31

Re: radiation on interfaces
 
Hi,

It depends whether you want to model radiation in the solid or not. If the solid is transparent (eg glass) then radiation can propagate through the solid. If the solid is opaque (eg steel) then radiation cannot propagate and radiation can be turned off for that domain. In this case the interface boundary condition allows you to set an emissivity on one side of the interface only.

Therefore you use "conservative interface flux" at the fluid-solid interface for radiation when the solid is transparent and you model radiation; you set emissivity and diffuse fraction if the solid is opaque and you do not model radiation in it.

Regards, Glenn Horrocks


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