Not able to find transmissivity

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Grab
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Not able to find transmissivity

Post by Grab »

Dear Elmer users,

I used to work with heat radiation with opaque materials. Currently, I would like to start analyzing heat radiation with semi-transparent materials.
However, I am unable to find how to define the transmissivity of a material. In the Elmer Models Manual, it is specified after the emissivity but impossible to find it.
Please could one of you help me on this topic?

Best regards,
Ben
kevinarden
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Re: Not able to find transmissivity

Post by kevinarden »

You can provide it in the boundary condition or the material property as
emissivity=1.0 (or whatever value you need)
raback
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Re: Not able to find transmissivity

Post by raback »

Hi,

It seems that the code expects "Transmittivity", not "Transmissivity". Maybe tells that it hasn't been too much used. It is not in keyword database so you need to cast the type "Real".

-Peter
kevinarden
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Re: Not able to find transmissivity

Post by kevinarden »

Sorry I mis-read the post
So according to Peter
Transmittivity = Real 1.0
Grab
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Re: Not able to find transmissivity

Post by Grab »

Thank you very much Kevin and Peter for your reply.

I forgot to mention one important thing : I am using ElmerGUI, and the transmissivity (or transmittivity) does not appear anywhere as far as I know.

Would it be taken into account if I include it in the material file (the .xlm in the Elmer folder)?

Thanks again for your help!
Ben
kevinarden
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Re: Not able to find transmissivity

Post by kevinarden »

On any of the forms in ElmerGUI you can use the free text input block and it will add any text you type to that section.
raback
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Re: Not able to find transmissivity

Post by raback »

...and you can also add it to the "heatequation.xml" file.

Btw, I changed the name in the code to "transmissivity". An updated binary will complain about "transmittivity". The former was clear winner in google fight.

-Peter
Grab
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Re: Not able to find transmissivity

Post by Grab »

Thank you both for your explanations, I will make some tests to see if it works well.

And thanks a lot for this great software!

Kind regards,
Ben
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