Production Methods of Liquid Hydrogen Fuel

Liquid hydrogen is used as a powerful and efficient propellant in spacecraft industries. This paper first presents the main principles of hydrogen liquefaction. Then, different methods for hydrogen liquefaction, including four general categories: precooled Linde-Hampson process, Claude process, helium-precooled Claude process and liquefaction by small cryo-coolers, are expressed along with their advantages and disadvantages. Considering native technology, the precooled Linde-Hampson process for small scale hydrogen liquefaction has been selected.