空间用液氦温区节流制冷机最小总功耗参数匹配策略研究

Research on the Matching Strategy of Minimum Power Consumption for Space Application Liquid Helium Temperature JT Cryocooler

氦节流(JT)制冷机已成为目前空间液氦温区制冷的主流技术之一。典型的氦JT制冷机包含了预冷机和节流压缩机两大耗功部件,对于氦JT制冷机的空间应用而言,预冷机和节流压缩机的总功耗是关键指标之一。研究100 mW@4.2 K的氦JT制冷机的最小总功耗,通过分析预冷温度和高压压力两个参数组合下制冷机所需的最小功耗,获得氦JT制冷机的最优运行参数。基于中国科学院上海技术物理研究所研制的两级脉管预冷机进行氦JT制冷机整机功耗的计算。计算结果表明,在100 mW@4.2 K的制冷目标下,当二级预冷温度为17.5 K,高压压力为1.85 MPa时,氦JT制冷机整机能效最高,总功耗为358 W,相对卡诺效率(rCOP)为1.96%。该最优运行参数匹配策略可用于选取两级预冷的大型节流装置最优运行参数。

Helium Joule-Thomson(JT)cryocooler has become one of the mainstream technologies for space liquid helium temperature cooling.The typical helium JT cryocooler contains two power-consuming components:precooler and JT compressor.For space application of helium JT cryocooler,the total power consumption of the precooler and JT compressor is the key indicator.This paper takes the 100 mW@4.2 K JT cryocooler as the research object,and the minimum power consumption as the goal.By analyzing the minimum power consumption required by the cryocooler under the parameter combination of precooling temperature and high-pressure,the optimal operating parameters of helium JT cryocooler are obtained.Based on the two stage pulse tube precooler develop by the Shanghai Institute of Technical Physics,the total power consumption of the JT cryocooler is calculated.The calculation results show that under the cooling target of 100 mW@4.2 K,when Tpre2 is 18 K,ph is 1.85 MPa,the overall energy efficiency of the cryocooler is the highest,the total power consumption is 358 W,and the relative Carnot efficiency(rCOP)is 1.96%.The optimal operating parameter matching strategy can also be used to select the optimal operating parameters of a two-stage precooling large-scale JT device.