超导磁体低温恒温器冷屏设计与测试  

Design and experiment of thermal shield of cryostat for superconducting magnet

作　　者：胡锐 丁开忠[1,3] 李蕾 杜双松 邹春龙 张华辉 冯昌乐 Hu Rui;Ding Kaizhong;Li Lei;Du Shuangsong;Zou Chunlong;Zhang HuaHui;Feng Changle(Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China;University of Science and Technology of China, Hefei 230026, China;Hefei CAS Ion Medical Technical Devices Co., Ltd, Hefei 230088, China)

机构地区：[1]中国科学院合肥物质科学研究院等离子体物理研究所,合肥230031 [2]中国科学技术大学,合肥230026 [3]合肥中科离子医学技术装备有限公司,合肥230088

出　　处：《低温工程》2021年第1期43-47,共5页Cryogenics

基　　金：国家自然科学基金青年基金(NO.52007183)。

摘　　要：现有的超导磁体系统中冷源与冷屏的距离较远,为了实现远端冷屏的有效降温,采用液氮为冷却介质,并通过冷源提供的冷量与冷屏热负荷实现冷却介质的热虹吸效应。对冷屏的冷却管路布置进行了有限元分析,预测了冷屏的稳态温度分布情况。冷屏降温测试表明:通过液氮强迫降温,冷屏可快速冷却至80 K,冷源开启后,液氮管路中形成热虹吸效应,可使冷屏系统稳定工作在液氮温区,且冷屏温度均匀,最大温度差不超过1.3 K。在低温恒温器运行过程中,冷却介质可通过自循环保持冷屏温度稳定。The cold source and the thermal shield was far apart from each other in the existing superconducting magnet system.In order to cooling the distal thermal shield effectively,liquid nitrogen was used as a cooling medium,and the thermosyphon effect was realized by the cooling capacity of cold source and the heat load of thermal shield.The temperature distribution of thermal shield in steady state was predicted by Finite Element Analysis.The cooling test shows that the thermal shield can be fast cooled to 80K by forced flow of liquid nitrogen,and the thermosyphon effect formed in liquid nitrogen pipes makes the thermal shield operate steady in temperature range of liquid nitrogen.The temperature distribution of thermal shield is uniform with the maximum difference in temperature less than 1.3K.Furthermore,the thermal shield can hold temperature steady by the automatic circulation of cooling medium during the operation of cryostat.

关 键 词：超导磁体 低温恒温器 冷屏 有限元 

分 类 号：TB657[一般工业技术—制冷工程] TB663