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Old   June 25, 2009, 11:21
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Hey there!

If you simulate radiation, u need to know the so called optical thickness. Can someone help me with this? For example i want to calculate the optical thickness of a air-film with 10mm thickness.

Thx a lot!
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Old   June 25, 2009, 17:22
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google wiki optical thickness air
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Old   June 26, 2009, 10:07
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Hi!

I searched google up and down and found nothing, thats why i asked my question in this forum! By the way the first entry in google is this post in this forum here ;-).
Can you gibe me better tipps?

Thx a lot!
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Old   June 26, 2009, 10:27
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Quote:
Originally Posted by ehrenwirth View Post
Hi!

I searched google up and down and found nothing
eh??

http://en.wikipedia.org/wiki/Optical_depth

I think you'd probably need to visit your university library borrow a physics book and read it. especially the bits that refer to wavelength



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air-film with 10mm thickness
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Old   June 26, 2009, 10:59
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Quote from Wiki:

"One way of visualizing optical depth is to think of a fog. The fog between you and an object that is immediately in front of you has an optical depth of zero. As the object moves away, the optical depth increases until it reaches a large value and the object is no longer visible."

Means air always has optical thickness of 0? I just wonder about the fact that in this forum so many people simulate radiation and the optical thickness seems to be the significant parameter to choose the radiation modell. So there must be a paper where you could get those values. but i dont find anything...why?
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Old   June 26, 2009, 11:36
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before even touching cfx you need to understand the basic principles and what you want to do.

here's a link to read as I still think that you have some more reading to do

anyway in cfx there are a few different radiation models to chose from. the manual has all the information you need to describe how these radiation models work.
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Last edited by ckleanth; June 26, 2009 at 19:37.
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