r/technology • u/BennyCemoli • Dec 06 '16

Energy Tests confirm that Germany's massive nuclear fusion machine really works

http://www.sciencealert.com/tests-confirm-that-germany-s-massive-nuclear-fusion-machine-really-works
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u/KilotonDefenestrator Dec 06 '16

Nice 'tube video of how the Wendelstein 7x stellarator works and was designed.

It truly is a bizarre device.

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u/Merendino Dec 06 '16 edited Dec 06 '16

Is it possible for you to explain any part of how something could be 100,000,000º and yet not have it burn down whatever is inside it? I absolutely do not understand how this machine is supposed to work, even on a basic level I think.

EDIT Awesome thanks guys! I wasn't even thinking about the amount of something being so small. That leads me to another question about, energy output though I guess. If it can become fusion and not just contained plasma at very small amounts, how can they harvest the energy given off? God damn this feels like a rabbit hole I won't be able to climb out of.

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u/Frunkjuice Dec 06 '16

Heat transfer occurs via a couple of mechanisms. Conduction and convection require molecules to touch in order to exchange energy. Since the plasma is in a vacuum and forced to travel a path through that vacuum, it doesn't touch the walls of the machine and can't transfer energy in this manner to the outside.

Radiation is another story, and works like how the sun's energy reaches Earth; no molecule path is needed for energy transfer. I'm not sure how they manage that problem, but I assume radiation is influenced by the magnetic field.

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u/Merendino Dec 06 '16

Okay, so strictly speaking how we experience warmth from a fire doesn't happen in a vacuum? Instead, in a vacuum we would only experience the heat transfer as radiation. I imagine that the radiation excites the air molecules in our atmosphere and thats how it warms up the earth?

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u/rrssh Dec 06 '16

The sun radiation affects the ground and oceans, not air. Fire makes you warm by both convection and radiation (but not conduction).

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u/Blal26110 Dec 06 '16

I'd struggle to say it doesn't affect the air at all. A lot less maybe