A machine compresses air from 15 to 3,000 pounds per square inch (psi).This is the same pressure used in SCUBA tanks. When you compress air, it heats up. We run that hot air through some coils of tubing. By blowing room temperature air over the coils, we cool the compressed air.
Then we let that compressed air expand. It gets cold when it expands. We let that cold air blow over the coils of tubing to cool some more compressed air even colder. Eventually, the compressed air is so cold that when it can expand it doesn’t. It has become a liquid!
EJ
(published on 10/22/2007)
(published on 09/29/2009)
