TY - JOUR
TI - Influence of heat in-leak, longitudinal conduction and property variations on the performance of cryogenic plate-fin heat exchangers based on distributed parameter model
AU - Jiang Qingfeng
AU - Zhuang Ming
AU - Zhu Zhigang
AU - Sheng Linhai
AU - Zhu Ping
JN - Thermal Science
PY - 2019
VL - 23
IS - 3
SP - 1969
EP - 1979
PT - Article
AB - For helium liquefaction/refrigeration systems, conventional design theory always fails in cryogenic applications and heat exchangers operating at low temperatures are usually sensitive to longitudinal heat conduction, heat in-leak from surroundings and variable fluid properties. Governing equations based on distributed parameter methods are developed to evaluate performance deterioration caused by these effects. The model synthetically considering these loss mechanisms is validated against experimental data and design results obtained by commercial software Aspen MUSETM. Sample multistream heat exchangers are further studied to discuss quantitative effects of these heat losses. In accordance with previous researches, the comprehensive effects of various losses are analyzed qualitatively in order to reveal their influences and investigate on the strategies of improving the heat transfer performance. The numerical method is useful in the design procedure of cryogenic heat exchangers and can be adopted to predict heat transfer and pressure drop performance under the actual low temperature environment.