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Author Topic: Is there a maximum temperature for a solar oven/furnace?  (Read 3220 times)

Offline CliffordK

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Is there a maximum temperature for a solar oven/furnace on Earth, or on the Moon?

Obviously the temperatures depend on the collector size and focal size, and perhaps the refractory nature of the solid/liquid, or perhaps gas being used in the collector.

However, is there any reason why one couldn't make a solar oven that was "hotter than the sun"?


 

Offline syhprum

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #1 on: 13/09/2013 20:09:29 »
I believe that this question has been discussed before on TNS and the surprising conclusion was that with the aid of multiple lenses you could
 

Offline yor_on

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #2 on: 16/09/2013 22:15:18 »
There should be. Heat is something in motion relative something else right? 'Bounces' translated into radiation. It depends on the material you use, circumstances defining where it is, etc. but i expect that there is a upper limit. although, if we talk 'temperatures' without source, I don't know.
 

Offline yor_on

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #3 on: 16/09/2013 22:32:20 »
Look at it like this, assume there is 'photons', then assume that to make a impact in our reality they have to be there for a measurable while. Then those are regulated by 'c', right? so, is there a ultimate frame of reference from where you can measure a photons energy, relative yourself? (temperature-wise)
 

Offline CliffordK

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #4 on: 16/09/2013 23:09:51 »
I've seen notes about some mirrored solar furnaces rated for about 3000C.  Perhaps the selection is because most materials melt below about 3000C.

If one's collector was a refractory material like Tantalum hafnium carbide, perhaps one could hit up to about 4000C before melting.  If one allowed a liquid collector, the boiling point of Tungsten Carbide is about 6000C, but then one runs into problems with containing it and insulating it.

I suppose the question might be why one would need anything quite so hot, although undoubtedly there would be industrial uses for the ability to melt and vaporize many substances.
 
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Offline syhprum

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #5 on: 18/09/2013 20:20:08 »
I think it can be done with a lens/mirror system that does not actually produce an image but I am unable to find the article describing how this was done but I well remember reading it !
 

Offline AlexBot

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #6 on: 24/07/2014 19:15:03 »
Hello,

teorically you may build a solar concentration adding mirrors and so adding energy from every mirror.
In small and medium scale this is always true.
I'm including a link to my solar oven page where there are also the calculation to know the maximum temperature it can reach.
This calculation is based to the fact that if you send energy in a box and do not let that go out then the system reach arising the temperature to push the energy to go out. So in the case of the oven temperature will be the equilibrium energy in = energy out. ;)
newbielink:https://plus.google.com/u/0/b/117106484937664501696/117106484937664501696/photos [nonactive]

In practice you cannot build a box to keep very high temperature (like the sun), and also every time you and a mirror you need to do it even far away from the center (from the hot) and this last mirror will add less energy of any closer. So for sure there will be a practical limit, but I do not see how to calculate it. :-\

Regards, Alex
 

Offline Bored chemist

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #7 on: 24/07/2014 20:46:16 »
Many of the important ideas were discussed here
http://www.thenakedscientists.com/forum/index.php?topic=41679.0
 

Offline Devora Kyles

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #8 on: 02/07/2016 16:22:19 »
It is not possible to make any tool/appliance that is hotter than sun.
 

Offline chiralSPO

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #9 on: 03/07/2016 03:06:05 »
This article might be useful here: https://what-if.xkcd.com/145/
 

Offline Bored chemist

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #10 on: 03/07/2016 14:17:00 »
It is not possible to make any tool/appliance that is hotter than sun.
Yes it is.
An arc welder will get things hotter than the surface of the sun.
Something like this
http://www.wired.co.uk/article/fusion-hots-up
 will get things hotter than the core of the sun.
 

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Re: Is there a maximum temperature for a solar oven/furnace?
« Reply #10 on: 03/07/2016 14:17:00 »

 

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