采用Gd_2O_2S回热填料的带预冷4K斯特林型高频脉管制冷机性能研究（英文）  

Performance of a precooled 4K Stirling type high frequency pulse tube cryocooler with Gd_2O_2S

作　　者：Zhuo-pei LI Yan-long JIANG Zhi-hua GAN Li-min QIU Jie CHEN 

机构地区：[1]Man-machine Environment Engineering, College of Aerospace Engineering,Nanjing University of Aeronautics and Astronautics [2]Institute of Refrigeration and Cryogenics, Zhejiang University [3]Nanjing Cooltech Cryogenic Technology Co., Ltd.

出　　处：《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》2014年第7期508-516,共9页浙江大学学报（英文版）A辑（应用物理与工程）

基　　金：Project supported by the National Natural Science Foundation of China(No.51106071);the Priority Academic Program Development of Jiangsu Higher Education Institutions,China

摘　　要：研究目的:研究新型磁性回热填料Gd2O2S对液氦温区高频脉管制冷机多级回热器损失特性的影响。创新要点:确定了不同回热填料以及运行参数(频率、平均压力)下液氦温区多级脉管制冷机的制冷温度和各级预冷量,进一步明确了4 K高频回热损失机理。研究方法:采用理论研究与实验验证相结合的方法,基于一台两级G-M型低频脉管制冷机预冷的单极斯特林型高频脉管制冷机,研究多级回热器在高频以及4 K温区下的损失特性。选取新型回热填料Gd2O2S替代部分回热填料HoCu2,比较回热器采用两种填料时在不同运行频率及平均压力下的冷端制冷温度(图10)、各级预冷量和预冷温度(图11–12)。重要结论:采用孔隙率较小的新型磁性回热填料Gd2O2S可显著改善第一级回热器内压力波与质量流的相位关系,从而减小该级回热损失。减小平均压力可以降低制冷机无负荷制冷温度并减小第二级预冷量,但制冷工质氦的体积比热容会急剧增大,从而使低温级回热器的换热对频率非常敏感。此外,频率对高温级回热器的回热特性影响不明显。该方法可以为三级斯特林型4 K多级脉管制冷机提供设计依据。The efficiency of 4 K Stirling type pulse tube cryocoolers （SPTCs） is rather low due to significant regenerator losses associated with the unique properties of helium around 4 K and the high operating frequencies. In this paper, regenerator per- formance at liquid helium temperature regions under high frequencies is investigated based on a single-stage SPTC precooled by a two-stage Gifford-McMahon type pulse tube cryocooler （GMPTC）. The 4 K SPTC used a 10 K cold inertance tube as phase shiflers for better phase relationship between pressure and mass flow. The effect of the operating parameters, including frequency and average pressure on the performance of the 4 K SPTC, was investigated and the first and second precooling powers provided by the GMPTC were obtained. To reduce the regenerator heat transfer losses, a multi-layer regenerator matrix, including Gd202S （GOS） and HoCu2, was used instead of a single-layer HoCu2 around 4 K. A theoretical and experimental comparison between the two types of regenerator materials was made and the precooling requirements for a regenerator operating at high frequencies to reach liquid helium temperatures were given, which provided guidance for the design of a three-stage SPTC.

关 键 词：斯特林型脉管制冷机 回热填料 4K 高频 预冷 低温惯性管 

分 类 号：TB651[一般工业技术—制冷工程]