Development of cold compressors for a 500 W@2 K superfluid helium refrigeration system

• Published in: Cryogenics (Guildford) 2023-06, Vol.132, p.103692, Article 103692
• Main Authors: Shang, Jin, Lv, Cui, Wang, Jinzhen, Chen, Huaiyu, Liu, Sihao, Li, Ziwei, Gong, Linghui, Wu, Jihao
• Format: Article
• Language: English
• Subjects: Cold compressor; External heat transfer; Superfluid helium
• ISSN: 0011-2275; 1879-2235
• DOI: 10.1016/j.cryogenics.2023.103692

•The first self-designed 500 W@ 2 K superfluid helium system including three cold compressors was operated stably in China.•Measuring the enthalpy difference between inlet and outlet helium gas can obtain the static heat leakages of cold compressors.•Reducing external heat leakages enhanced the isentropic efficiencies of cold compressors obviously. A superfluid helium refrigeration system is a necessity for the cooling equipment in many large-scale scientific facilities. As an essential device, a type of cold compressor is designed and manufactured in this paper. It mainly consists of motor, bearings, compressor components, and heat insulation. After conducting tests at both ambient temperature and low temperature, the target of long-term stable operation at 500 W@2 K was finally achieved. The structure and test results of the cold compressor are summarized. The isentropic efficiencies of cold compressors were between 50% and 70%, and the heat leakage was less than 40 W.