用于CEPC探测器超导磁体的小型氦虹吸回路实验研究

摘要

In the background of the cryogenic thermosyphon cooling system design of a circular electron positron collider (CEPC) large detector superconducting magnet under conceptual phase at IHEP-China,building a two-phase He I natural circulation loop,helium was used as the working fluid,to investigate the heat and mass transfer characteristics experimentally.The pressure and temperature as a function of heat flux were measured and the heat transfer coefficient were calculated at the working position.It turns out that filling ratio has a significant effect on thermosyphon cooling circulation,under a suitable filling ratio of 40 ～55％,the system would work normally.Otherwise heat transfer coefficient varies at different position of tube,boiling crisis originates in the upper firstly,then develop to the entrance.%在环形正负电子对撞机(CEPC)大型探测器超导磁体拟采用低温虹吸冷却系统的预研背景下,搭建了氦低温虹吸冷却回路实验平台,进行了气-液两相自然循环传热传质特性实验研究.实验测量了不同充装量下,压力、温度随热流量的变化规律,计算了实验段的表面传热系数.研究表明,充装率对热虹吸冷却循环具有重要影响,在40％～55％合适的充装率下能够保证该系统的正常运行;另外实验段不同位置的表面传热系数不同,烧干先在上端发生,然后逐渐向下端发展.