热容和热阻法抑制低温制冷机冷头温度波动实验研究  

Experimental Study on Suppressing Temperature Oscillation on Cold Head of Cryocooler by Heat Capacitance and Thermal Resistance Method

作　　者：胡子峰[1] 朱佳奇[1] 陈功[1] 杨忠衡 黄永华[2] HU Zifeng;ZHU Jiaqi;CHEN Gong;YANG Zhongheng;HUANG Yonghua(Shanghai Institute of Quality Inspection and Technical Research,Shanghai 201114,China;Institute of Refrigeration and Cryogenics,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海市质量监督检验技术研究院,上海201114 [2]上海交通大学制冷与低温工程研究所,上海200240

出　　处：《制冷技术》2022年第4期1-7,14,共8页Chinese Journal of Refrigeration Technology

基　　金：上海市市场监督管理局科技项目(No.2021-33)。

摘　　要：为了满足基于低温制冷机的干式低温恒温器温度稳定性需求,本文采用基于氦气的热容法和基于不锈钢叠片的热阻法,研究了4~20 K温区其对二级G-M低温制冷机冷头温度波动的抑制效果。实验结果表明:在4.2 K温区热容模块充注9 mL液氦可将冷头温度波动减小75%左右;但随着恒温器控温点的升高,难以保持高效的控温稳定性和波动抑制效果;相比热容法,热阻法可有效地将与冷头相连的恒温块温度波动降低一个数量级;对比分析不同厚度热阻片的作用效果,发现采用厚度超过0.5 mm以上的不锈钢热阻片可使恒温块的温度波动抑制在10 mK以内。In order to meet the temperature stability requirements by dry cryostats based on cryocoolers, the helium-based heat capacity method and the stainless-steel lamination-based thermal resistance method have been adopted to investigate their temperature fluctuation suppression effect on the second stage cold head of a G-M cryocooler in the range of(4-20) K. The experimental results showed that the temperature fluctuation on the second-stage cold head can be reduced by approximately 75% by filling the heat capacity module with 9 mL of liquid helium at 4.2 K. However, with the increase of the temperature set point, it becomes difficult to maintain temperature control stability and achieve the fluctuation suppression effect. Compared to the heat capacity method,the temperature fluctuation of the isothermal block connected to the cold head can be reduced by an order of magnitude by using the thermal resistance method. The effect of the steel sheets with different thicknesses was compared and analyzed. It is found that the temperature fluctuation on the isothermal block can be suppressed to within 10 mK when the thickness is greater than 0.5 mm.

关 键 词：低温恒温器 温度波动 抑制方法 热阻法 热容法 

分 类 号：TB651[一般工业技术—制冷工程] O514.2[理学—低温物理]