How to design a cryogenic Joule-Thomson cooling system: case study of small hydrogen lique er

Heat exchangers are the critical components of refrigeration and liquefaction processes. Selection of appropriate operational conditions for the cryogenic recuperative heat exchanger and expansion valve operating in a Joule-Thomsoncooling system results in improving the performance and ef ciency. In the current study, a straightforward procedure is introduced to design an ef cient Joule- Thomson cooling system. Determining the appropriate operational conditions and con guration of streams within the recuperative heat exchanger are discussed comprehensively. A Joule-Thomson cooling system including a helically coiled tube in the tube heat exchanger and expansion valve was considered as a case study. Simulation was performed by a procedure different from the conventional  nite element method and the results were validated versus data obtained from a small laboratory hydrogen lique er. In accordance with mathematical modeling performed on the recuperative heat exchanger, it is better to  ow low pressure hydrogen inside the inner tube and high pressure hydrogen within the annulus. This arrangement results in needing shorter length heat exchanger tubes as compared with the reverse arrangement.