PAPS超流氦低温系统中2K负压换热器的设计与优化

Design and optimization of 2K sub-atmospheric heat exchanger in PAPS superfluid helium cryogenic system

先进光源技术研发与测试平台(PAPS)需要2K超流氦系统为超导腔提供低温环境,2K负压换热器是低温系统的关键部件,考虑氦工质的物性随温度变化较剧烈,采用分段法对换热器进行计算,建立了2K负压换热器的计算模型,基于该模型编写了换热器的设计及校核计算程序,并对换热器进行了优化。结果表明,结构参数对换热性能有较大的影响,优化后的换热器所需的换热面积减小,换热系数增加,低压侧压降降低。

Platform of Advanced Photon Source Technology R & D( PAPS) needs 2 K superfluid-helium system to provide cryogenic environment for the superconducting cavity,and 2 K sub-atmospheric heat exchanger is the critical component of cryogenic system. Considering physical property of helium changes sharply as the temperature varies,sectioning method is adopted for heat exchanger computation. This paper established 2 K sub-atmospheric heat exchanger calculation model,writied designing and verifying calculation programme based on the calculation model,and optimized the heat exchanger. Result shows that structural parameters can greatly influence the heat exchange performance,surface area needed by the optimized heat exchanger decreases,coefficient of heat transfer increases,and pressure drop for the shell side decreases.