I been trying to find details for how cryocooling works, how do they make liquefied oxygen, hydrogen, helium, what are the energy efficiencies and throughputs, details. If you wanted to store LH2 and LO2 in space in say a L1 deport and keep it cool, how would you do it?
It is well known that the air liquefaction system developed by Carl Linde in 1895 was the first commercially successful cryogenic system. Most of the modem industrial cryogenics was later developed based on inventions of Carl Linde. The works of Linde were highly appreciated by D. Mendeleew and N. Umov in Russia. Moscow University purchased the air liquefier made by Linde in 1898, thus the first cryogenic laboratory for education purposes was organized in Russia. Though the process developed by Linde was relatively simple and reliable, it had some disadvantages, the major one of which was poor efficiency and thus high power consumption. Today we know, that the thermodynamic efficiency of the cold part of the Linde's system r/e was lower than 10 % due to the huge temperature difference between warm and cold streams in the heat exchanger. Of course, C. Linde, as well as other engineers and inventors, tried to improve the efficiency of the process For example, C. Linde introduced an additional precooling system based on a classic ammonia refrigerator. That way he managed to reduce a temperature difference between the warm and cold streams in heat exchanger, consequently reducing the temperature of the stream before throttling valve, and increasing efficiency of the process. Peter Kapitza developed further the idea of G. Claude; he developed a highly efficient turbine-expander (isentropic efficiency higher than 80 %) and reduced the operation pressure further to 6---8 bar. The temperature difference in the heat exchanger was reduced, the expansion losses in the turbine were small, so the cold part of this process was practically loss-free compare to the original Linde's system; the efficiency of the cycle was increased essentially.
