Cooling a craft if the external temperature is higher than the medium you are using to cool it is?

[Wraithlabs]

I am trying to figure out how to cool a craft's internal space but i am running into a problem where i am having trouble understanding how a craft could be cooled if the external temperature would be hotter where the heat dump is. I need some help understanding how you could transfer the internal heat and transfer it out of the craft and away from the vehicle if the external temperature is higher than the medium you are using to cool the craft would be. For instance if you were sending a craft into the core of the planet, how could you cool the craft if the external temperature is higher than the temperature of the fluid you are using to care the heat away with is exceeded. Would that not reverse the heat flow and pump heat back into the system thus defeating the purpose of the cooling system? Any help with this subject would be greatly appreciated. I look forward to hearing from all of you. Yes, i know this is a basic thermodynamics question, but i am just looking to get my head around this and understand any way to transfer the heat out of the internal area of the craft and into the surrounding environment. Also please let me know if i am totally not understanding how this could work and that there is no way to cool the internal space. I just want to know if i'm either correct in assuming that heat transfers from high temperature to low temperature or if there is other ways to transfer the heat that i don't know of.

 

[GregLocock]

How exactly did you get through uni without understanding how a refrigerator works? You may have noticed that the freezer compartment is bit colder than the air in your kitchen.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[Wraithlabs]

I totally understand how a refrigerator works. That's not my question. What I have learned and understand tells me that you would be unable to cool an area if the area in which you are dumping the heat is hotter than the refrigerant in the exterior stage. Thus the heat would flow back into the system and not away from it. All I am asking is am I correct in my thought that this would not function as a cooling system?

Thank you.

 

[IRstuff]

If you know how a refrigerator works, then you know that your premise is incorrect, as Greg had already made clear.

TTFN
I can do absolutely anything. I'm an expert!
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faq731-376 forum1529

 

[Wraithlabs]

That's all I was asking. I just wanted to confirm I wasn't missing something. Thanks for your help and your kind words.

 

[amorrison]

Check out the Russian Venus landers in the 1960's .
The surface temperature of Venus is 700 F , the landers internal electronics will fry at 300 F.
Solution - insulated box - with electronics inside, liquid next then the insulation on the hot outside.
Some liquid was chosen that would vaporize to "take away the heat" that was flowing from the 700 F to the 300 F.
Once all the liquid had vaporized the electronics fried - maybe 2 hours since landing.