脉管制冷机室温换热器强化辐射换热研究  

Research on Radiation Heat Transfer Enhancement of Room-temperature Heat Exchanger of Pulse Tube Cryocoolers

作　　者：李政坤 俎红叶 戴巍[1,2] 李永 李珂[1] 李江涛[1,2] LI Zhengkun;ZU Hongye;DAI Wei;LI Yong;LI Ke;LI Jiangtao(Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院理化技术研究所,北京100190 [2]中国科学院大学,北京100049

出　　处：《工程热物理学报》2023年第4期1023-1029,共7页Journal of Engineering Thermophysics

基　　金：科技部重点研发计划课题(No.2021YFC2203303)。

摘　　要：脉管制冷机是目前最常用的高效小型低温制冷机之一。相对于主动散热,采用被动散热的室温换热器具有可靠性高与使用便捷等优点。辐射换热强化是提高室温换热器性能的一种方法。本文选取了一种小型脉管制冷机,研究在其主肋片换热器表面涂覆高发射率涂层对整机散热性能的影响。在自然对流条件下实验,对比涂覆高发射率涂层前后制冷机的运行温度。结果表明,喷涂高发射率涂层后,制冷机电机温度基本不变,冷指下方的辅助肋片换热器温度下降了约1~2℃,而主肋片换热器温度下降了约3~4℃。通过理论推算得,改变发射率前后主肋片换热器的辐射换热占比从8.6%提升至29.7%。结果证明强化辐射换热降低了制冷机室温换热器的工作温度,是一种改善小型制冷机散热的可行方法。Pulse tube cryocooler is one of the widely used cryogenic refrigerators.Compared with the active heat dissipation,the room-temperature heat exchanger with passive heat dissipation could improve reliability and convenience of the equipment.Enhanced radiative heat transfer can be applied to improve its heat dissipation performance.In this paper,a type of pulse tube refrigerator is selected and the influence of a high-emissivity coating on the heat dissipation performance of main finned heat exchanger is studied.Under natural convection conditions,the operating temperatures of the cryocooler without and with high emissivity coating are compared and analyzed.The experimental results show that after spraying the high emissivity coating,the motor temperature of the refrigerator was almost the same.The temperature of the auxiliary heat exchanger below the cold finger decreased by about 1~2℃,while the temperature of main finned heat exchanger decreased by about 3~4℃.The analysis shows that the radiation ratio of main finned heat exchanger with the high-emissivity coating increased from 8.6%to 29.7%.The results show that enhancing radiation heat transfer can reduce the operating temperature of the room-temperature heat exchanger,which is a feasible method to improve the heat dissipation performance of the cryocoolers.

关 键 词：高发射率涂层 换热器 辐射换热 自然对流 

分 类 号：TK124[动力工程及工程热物理—工程热物理]