特殊工况下的高温超导磁体冷却系统的设计

Design of HTS magnet cooling system under special working condition

特殊工况下的高温超导磁体的设计要求是在30分钟内快速降温到63K以下,并且保持磁体在工作温度下持续工作至少8个小时。提出了采用液氮浸泡磁体,并通过液氦预冷和减压对液氮进行冷却,使液氮快速降温到63K以下形成固态氮的冷却方式。计算了磁体运行时的总热负荷,对比全部利用固氮维持磁体运行、部分利用固氮作为储冷介质同时利用斯特林制冷机制冷维持两种维持磁体低温运行方案,最终确定第二种冷却方案。

The operating requirements of high temperature superconductor （HTS）magnet under special working condition was to be cooled to 63K rapidly in 30 minutes, and working continually for at least 8 hours under working temperature condition. Utilizing hquid nitrogen to soak magnet was proposed, then cooling liquid nitrogen by liquid helium pre - cooling and decompress- ing. The total load of the operating magnet was calculated. By contrasting two magnet operation options of utilizing solid nitrogen entirely to maintain magnet operating and utilizing solid nitrogen partly as cold storage material and stirling cryocooler to remain low temperature, the second scheme was chosen.