Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Hannah LS on 27/11/2018 12:00:01
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Donald asks:
My vacuum double walled stainless steel tumbler maintains my coffee hot for 12 hours, without adding heat! If the International Space Station is wrapped in metal and in a vacuum, with continuous heat production internally from people and electronics, how do they ever get rid of the heat? Yes I know, cooling, but how?
What do you think?
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The ISS has thermal radiation panels which radiate excess heat into space. 0ne reason your stainless steel tumbler works as well as it does is that it is also designed to minimize heat loss through radiation. With the ISS, excess heat is carried by a fluid (ammonia), from the interior to the radiator panels, which are designed to be good radiators of heat. (vacuum only prevents heat loss via conduction or convection). The fluid is pumped back to the interior and picks up more heat.
The space shuttle used a similar system and its radiators where mounted on the inside surface of the cargo bay doors. One of the first things the shuttle did after achieving orbit was to open the doors in order to deploy the radiator system. If the doors had failed to open they would have had to shorten the mission in order to prevent overheating.