热阻法抑制脉管制冷机冷头温度波动研究

Reduction of temperature oscillation with the thermal resistance method for a pulse tube cryocooler

低温冷冻靶等应用要求目标控温波动度小于1m K量级。为了实现这一亚毫开级的高精度控温,并揭示控制措施对抑制温度波动的定量作用机理,基于脉管低温制冷机搭建了深冷温控测试平台。采用热阻法,即通过在制冷机冷头和被测样品之间插入不锈钢薄片组合来引入传热热阻,对模拟样品的温度波动进行实验测量,获得了制冷机二级冷头在5~30K温区的温度波动情况和传热热阻之间的定量关系。增加传热热阻是抑制温度波动的有效手段。

Applications such as the cryogenic target require temperature oscillations within the order of 1 inK. To realize this high precise temperature control and reveal the mechanism between control methods and temperature fluctuations, a temperature measurement cryosystem based on a pulse tube cryocooler was established. The temperature vibration was decreased with thermal resistance methods that stainless -steel dampers were inserted between cryocooler cool head and the sample to increase thermal resistance. The quantitative relationship between temperature fluctuations and thermal resistance was obtained ranging from 5 30K of the cryocooler 2nd cool head. It is concluded that increasing heat resistance is an effective means to suppress temperature oscillations.