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COMSOL 4: "Reradiating Surface"

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Hi there,

I'm interested about new features of COMSOL 4.

Especially I would like to know what the "Reradiating Surface" boundary condition is, which is avaivible in the heat Transfer Module. Is it a diffusive reflector?

I'm using 3.5a and there is no such feature.

kind regards

3 Replies Last Post Dec 8, 2010, 7:28 a.m. EST
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Dec 7, 2010, 10:43 a.m. EST
Hi

if you take the HT user guide V4.1 on p89 you will read

The Reradiating Surface feature is a variant of the surface-to-surface radiation feature
with e = 0. Reradiation surfaces are common as an approximation of a surface that is
well insulated on one side and for which convection effects can be neglected on the
opposite (radiating) side.
It resembles a mirror that absorbs all irradiation and then
radiates it back in all directions: J = G. The feature adds the radiosity dependent
variable to its selection and uses it as surface radiosity.

Heat flux on surface-to-surface boundary is zero:

.....

--
Good luck
Ivar
Hi if you take the HT user guide V4.1 on p89 you will read The Reradiating Surface feature is a variant of the surface-to-surface radiation feature with e = 0. Reradiation surfaces are common as an approximation of a surface that is well insulated on one side and for which convection effects can be neglected on the opposite (radiating) side. It resembles a mirror that absorbs all irradiation and then radiates it back in all directions: J = G. The feature adds the radiosity dependent variable to its selection and uses it as surface radiosity. Heat flux on surface-to-surface boundary is zero: ..... -- Good luck Ivar

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Posted: 1 decade ago Dec 8, 2010, 5:09 a.m. EST
Hi Ivar,

if I had Comsol 4.1, then I would take the HT user guide and then I would read on page 89 " .... " but ... I haven't ;)

So thanks (again). I expected that this boundray condition would work like this.


Best regards
Hi Ivar, if I had Comsol 4.1, then I would take the HT user guide and then I would read on page 89 " .... " but ... I haven't ;) So thanks (again). I expected that this boundray condition would work like this. Best regards

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Dec 8, 2010, 7:28 a.m. EST
Hi

well then you have part of the page on my previous post. You should get in contact with your local rep or xou COMSOl administrator to get access to latest 4.1 as ist much better documented and more stable than the first 4.0a even.

Another way is to search on the web ...

--
Good luck
Ivar
Hi well then you have part of the page on my previous post. You should get in contact with your local rep or xou COMSOl administrator to get access to latest 4.1 as ist much better documented and more stable than the first 4.0a even. Another way is to search on the web ... -- Good luck Ivar

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