用于CEPC探测器超导磁体的小型氦虹吸回路实验研究

Experimental study of a small-sized He I thermosyphon for the detector superconducting magnet of the CEPC

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。

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.