Numerical study of a cryogen-free vuilleumier type pulse tube cryocooler operating below 10 K

[摘要] This paper presents a numerical investigation on a Vuilleumier (VM) type pulse tube cooler. Different from previous systems that use liquid nitrogen, Stirling type pre-coolers are used to provide the cooling power for the thermal compressor, which leads to a convenient cryogen-free system and offers the flexibility of changing working temperature range of the thermal compressor to obtain an optimum efficiency. Firstly, main component dimensions were optimized with lowest no-load temperature as the target. Then the dependence of system performance on average pressure, frequency, displacer displacement amplitude and thermal compressor pre-cooling temperature were studied. Finally, the effect of pre-cooling temperature on overall cooling efficiency at 5 K was studied. A highest relative Carnot efficiency of 0.82 % was predicted with an average pressure of 2.5 MPa, a frequency of 3 Hz, a displacer displacement amplitude of 6.5 mm, ambient end temperature 300 K and pre-cooling temperature 65 K, respectively.

[发布机构] Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, China^1;University of Chinese Academy of Sciences, Beijing, China^2

[效力级别] 物理学 [学科分类] 材料科学（综合）

[关键词] Component dimensions;Cooling efficiency;Displacement amplitudes;Numerical investigations;Optimum efficiency;Pulse tube cryocoolers;Thermal compressors;Working temperatures