液氢储罐蒸气冷却屏多层绝热性能分析

Performance analysis of multi-layer insulation for vapor-cooled shield of liquid hydrogen storage tanks

针对液氢存储时由于与环境温差大而导致的漏热较大的问题,建立耦合蒸气冷却屏的多层绝热结构的传热模型,同时引入氢仲正转化进一步降低液氢储罐漏热,采用MATLAB自编程方法,分析多层绝热结构、仲正转化、蒸气冷却屏个数及排列方式对绝热结构性能的影响。研究结果表明:单个蒸气冷却屏的加入使多层绝热性能得到大幅提升,净热流密度最多下降61.3%,最佳屏位出现在绝热结构中心附近;氢仲正转化的加入能够使结构的绝热性能进一步提升,净热流密度最多下降11.1%;串联型蒸气冷却屏的绝热性能明显优于并联型蒸气冷却屏;当蒸气冷却屏数量由1增加至3时,净热流密度分别降低22.8%和10.9%。研究结果可为液氢储罐耦合蒸气冷却屏的多层绝热结构的设计和优化提供理论参考。

In view of the problems of significant heat leakage caused by the large temperature difference between liquid hydrogen storage and the outside environment,a heat transfer model of a multi-layer insulation structure coupled with vapor-cooled shields was established,and para-ortho hydrogen conversion was introduced to further reduce the heat leakage of liquid hydrogen storage tanks.MATLAB self programming method was used to analyze the effects of multi-layer insulation structure,para-ortho hydrogen conversion,number and arrangement of vapor-cooled shields on the performance of insulation structure.The results show that the addition of a single vapor-cooled shield significantly improves the performance of multi-layer insulation,with a maximum decrease of 61.3%in net heat flux and the best shield position occurring near the center of the insulation structure.The addition of para-ortho hydrogen conversion further enhances the insulation performance of the structure,with a maximum decrease in net heat flux of 11.1%.The insulation performance of the series type of vapor-cooled shields is significantly better than that of the parallel type of vapor-cooled shields.When the number of vapor-cooled shields increases from 1 to 3,the net heat flux decreases by 22.8%and 10.9%.The results can provide theoretical reference for the design and optimization of composite multi-layer insulation structures for liquid hydrogen storage tanks.