how can we duplicate Chinise powerless freezing technology?

[inbilya]

When the Chinese built their high altitude railway , a 550km section of permafrost had to be crossed. They built these simple freezers to keep the permafrost frozen. These were long pipes filled with liquid nitrogen, and installed vertically into the ground about halfway in. Somehow the circulation of liquid nitrogen through I guess - evapuration and condensation causes the bottom portion to work as a freezer. I don't know much about this at all , my Idea is - if it does not take power to work, why not put it to use . I want to convert my shed into a huge refrigirator. wonder if it will work and how many pipes it would take for a 10x10 shed? what diameter pipe to use? how much to fill it. ? if any of you guys know any information please share. please don't laugh too hard as I don't know much about refrigiration. more information can be found on google , just type - altitude railway , a 550km section of permafrost.

[flyinkiwi]

Ah, the familiar blasphemy of perpetual motion!

http://bit.ly/WuUBfh
http://bit.ly/10hjnYp

Only if your ambient is below your desired space temperature... if that is that case, why not just ventilate and humidify like a Colorado or Idaho potato shed?

[SeanB]

Watched the video, and they are using ammonia heat pipes to keep the ground cold. Basically in winter they freeze the ground as the air is so much colder than the ground that the simple heat pipe will run to transfer heat up the pipe as vapour to condense and run back down as liquid ammonia. In summer or when the top is warm the pressure increases so the ammonia will not boil, so then there is minimal heat transfer back down. Basically a heat pipe with no wicking so the unit is unidirectional, only pumping heat from the bottom to the top. It works because there are very few hot days, and many cold nights where the pipes can transfer heat up to radiate to space in the clear dry air. Really interesting show that was.

[inbilya]

thanks for replies. I guess this was another vain idea , well at least I learned something out of this.