Study of Refrigerant Circulation System and Cryofan for Cooling High Temperature Superconducting Coil

A circulation cooling system is mentioned as a method for efficiently cooling high-temperature superconducting coils (HTS coil), and the purpose is to keep the temperature of the HTS coil to about 50 K or less. In addition, it is necessary to clarify what kind of change occurs if a room temperature compressor or a cryofan are used for the circulation device as the cooling performance of the circulation cooling system. In this study, we analyzed the cases where multiple HTS coils were cooled, using a room temperature compressor and cryofan as the circulation device, and using helium and hydrogen as the refrigerant, and compared their characteristics. As a result, it was shown that the cooling capacity the system that uses the cryofan is higher than that of using the compressor. Focusing on the refrigerant, it was shown that hydrogen has better cooling performance than helium.