超低温温区热连接方式试验研究

Experimental Study on Thermal Connection Mode in Ultra-low Temperature Region

为验证超低温温区不同热连接方式对深冷辐射源的降温影响程度,搭建了超低温温区真空热试验系统,对三种型式的热连接件的超低温导热特性进行了试验。结果表明:40K以下高纯铜与铝呈现出极好的超低温导热特性;在结构允许的前提下,可通过增大热连接件导热截面积、缩短导热路径、降低热连接件热容的方式来降低冷屏降温时间;同时可通过采用柔性热连接件实现冷屏的非定向结构优化。研究结果可用于指导深冷辐射源结构优化与非定向深冷辐射源设计,为深冷辐射源试验的开展提供试验数据。

In order to verify the influence of different thermal connection modes in ultra-low temperature zone on the cooling of cryogenic radiation source,a vacuum thermal test system in ultra-low temperature zone was established,and the ultra-low temperature thermal conductivity characteristics of three types of thermal connectors were tested.The results show that the high purity copper and aluminum below 40 K show excellent thermal conductivity performance.Under the premise of structural permits,the cooling time of the cold shield can be reduced by increasing the thermal cross-sectional area of the thermal connector,shortening the thermal path and reducing the heat capacity of the thermal connector.At the same time,the non-directional structure of cold shield can be optimized by using flexible thermal connectors.The results can be used to guide the structure optimization of cryogenic radiation source and the design of non-directional cryogenic radiation source,and provide experimental data for cryogenic radiation source test.