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Author Topic: is a cold flame possible?  (Read 5547 times)

paul.fr

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is a cold flame possible?
« on: 31/08/2007 09:08:30 »
is it possible to have a cold flame, or one cold enough that you could touch it without getting burnt?


 

Offline JP

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is a cold flame possible?
« Reply #1 on: 31/08/2007 18:45:44 »
The usual definition of flame is the gas/soot mixture given off in a combustion reaction.  In these cases, the answer is probably "no."  The primary reason the gas/soot mixture glows is that it's heated and is giving off blackbody radiation, which (as has been discussed on here recently) depends strongly on temperature.  In other words, to get visible light from this gas and soot, you need it to be hot.

Now, you could probably tailor some gas to glow like a flame, since there are ways of making matter glow without heating it, but it's not the traditional definition of a flame.
 

Offline Soul Surfer

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is a cold flame possible?
« Reply #2 on: 31/08/2007 22:46:22 »
It might just be possible within the definition of a flame if you could find  a low energy gaseous chemical reaction that generated light rather than heat like the luminescent chemical reactions you get in those chemical light tubes.  but I can't think of one at the moment.  A mixture of ammonia and hydrogen chloride gas will produce lots of white "smoke" of ammonium chloride but that's not the same thing.
 

Offline BillJx

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is a cold flame possible?
« Reply #3 on: 04/09/2007 01:45:15 »
During the Yukon gold rush there were jokes and tall tales along the lines of "it was so cold that night, the flame froze right there on the candle.  I left it there all day, and come nightfall I  warmed it against my body to resurrect it."
 

Offline syhprum

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is a cold flame possible?
« Reply #4 on: 04/09/2007 07:29:12 »
I think circus performers use Phosphorous compounds to produce a low temperature flame simulation but it is very poisonous
« Last Edit: 04/09/2007 07:51:16 by syhprum »
 

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is a cold flame possible?
« Reply #4 on: 04/09/2007 07:29:12 »

 

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