650MHz超导腔的传导冷却结构设计及数值模拟

Design and numerical simulation of conduction cooling structure of 650 MHz superconducting cavity

为了实现仅依靠小型制冷机和热传导方式带走超导腔热量、抛弃复杂的液氦系统,对超导腔的传导冷却结构展开了研究。根据传热要求为650 MHz超导腔初步设计了5种不同的冷却结构,并使用数值模拟软件进行传热仿真,研究了不同的冷却结构、冷却结构的材料和接触热阻等因素对冷却效果的影响。研究结果表明:设计3个冷头比2个冷头更合理,连接冷头和冷环的热桥长度与超导腔的温度近似成线性关系,束管处的热桥有利于截断束管漏热。热桥材料采用高纯铝的冷却效果好于高纯无氧铜,同时热桥与冷环的接触热阻应控制在10 K·cm^(2)/W以下。

In order to take away the heat of superconducting cavity and discard the complex liquid helium system by relying only on cryocoolers and heat conduction,the conduction cooling structure of the superconducting cavity was studied.According to the heat transfer requirements,five different cooling structures were preliminarily designed for the 650MHz superconducting cavity,and the heat transfer simulation software was used to simulate the heat transfer,and the influence of different cooling structures,cooling structure materials and contact thermal resistance on the cooling effect was studied.The results show that it is more reasonable to design three cold heads than two cold heads.The length of the thermal link connecting the cold head and the cold ring is approximately linear with the temperature of the superconducting cavity,and the thermal link at the beam tube is conducive to cutting off the heat leakage of the beam tube.The cooling effect of the thermal link material using high-purity aluminum is better than that of high-purity oxygen-free copper,and the contact thermal resistance between the thermal link and the cold ring should be controlled below 10 K·cm^(2)/W.