Design and component development of a 17 l/d liquefier for helium recondensation

27th International Cryogenics Engineering Conference and International Cryogenic Materials Conference 2018

Kranthi Kumar, J.^1 ; Jacob, S.^1 ; Karunanithi, R.^1 ; Narasimham, Gsvl^2

Center for Cryogenic Technology, Indian Institute of Science, Bengaluru, India^1

Dept. of Mechanical Engineering, Indian Institute of Science, Bengaluru, India^2

关键词: Cooling power;    Design and Development;    Discharge pressures;    Liquid fraction;    Primary cooling;    Pulse tube coolers;    Recondensation;    Recuperative heat exchangers;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/502/1/012010/pdf
DOI  :  10.1088/1757-899X/502/1/012010

来源: IOP

【 摘 要 】

This paper describes the design and component development of a 17 l/d liquefier for helium recondensation. The liquefier uses an oil-free linear motor compressor with suction and discharge pressures at 1 and 22 bar respectively. The liquefier is a hybrid cryocooler consisting of an interchanging component made up of recuperative heat exchangers, an 80 K pulse tube cooler (PTC) and a 25 K two stage PTC. The cooling powers required of the PTC's are 14.2 W at 80 K and 1.6 W at 25 K. The primary cooling mechanism is two stage J-T expansion at 22 bar and 11 bar resulting in liquefaction with a liquid fraction of 0.19. This corresponds to a cooling power of 0.54 W at 4.2 K and a liquefaction rate of 17.8 litres per day. An overview of the design and development of the PTC's, heat exchangers and JT valves is presented.