车载液氢瓶瓶内自增压过程热力耦合特性研究  

Study of thermodynamic coupling characteristics in self-pressurization process within liquid hydrogen tank for vehicles

作　　者：朱宇豪 卜玉[2] 刘瑞敏[2] 高婉丽[2] 郭琬 谢福寿 Zhu Yuhao;Bu Yu;Liu Ruimin;Gao Wanli;Guo Wan;Xie Fushou(Institute of Refrigeration and Cryogenic Engineering,Xi’an Jiaotong University,Xi’an 710049,China;Beijing Institute of Aerospace Testing Technology,Beijing 100074,China)

机构地区：[1]西安交通大学制冷与低温工程研究所,西安710049 [2]北京航天试验技术研究所,北京100074

出　　处：《低温工程》2023年第5期61-68,共8页Cryogenics

基　　金：国家自然科学基金(52276018);国家重点研发计划(2019YFB1504900);中国博士后科学基金(2021T140538)。

摘　　要：考虑气液相变作用、流固耦合传热及支撑结构非均匀漏热条件,建立了描述车载液氢瓶瓶内热质传递过程的全三维数值模型,分别对30%与70%充注率下液氢瓶瓶内自增压过程开展仿真研究。研究结果表明:初始液位对液氢瓶气枕增压规律有显著影响,与30%液位工况对比,70%加注液位下增压速率明显更快,二者在5000 s内平均压升速率分别为8.562 kPa/h和13.168 kPa/h;自增压过程中,由于液面处产生的蒸发气体向气瓶顶部聚集过程中将热量不断携带至气枕区,气相温升速率明显高于液相;液氢瓶内流体在近壁面处易形成许多涡流,且界面处产生的蒸发气体有贴壁扩散的趋势。A three-dimensional simulation model is established in this paper to describe the heat and mass transfer process within the liquid hydrogen tank for vehicles.The phase change process,the effect of fluid-structure coupling heat transfer and non-uniform heat leakage are considered.The self-pressurization processes in liquid hydrogen tank at 30%and 70%filling rates are numerically conducted.The simulation results show that the initial liquid level has a great influence on the pressure variations of the ullage within the liquid hydrogen tank.The pressurization rate at 70%filling level is significantly faster than that at 30%liquid level.Under the filling rate of 30%and 70%,the average pressurization rate within 5000 s is 8.562 kPa/h and 13.168 kPa/h,respectively.In addition,during the self-pressurization process,the evaporating gas generated at the interface accumulates to the top of the tank and carries heat continuously to the ullage,leading to the temperature rise rate of vapor is obviously higher than that of the liquid.Furthermore,the fluid inside the liquid hydrogen tank forms large amount of vortices near the walls,and the boil-off gas at the interface has a tendency to diffuse against the walls.

关 键 词：车载液氢瓶 自增压 相变 热力耦合 数值仿真 

分 类 号：TQ116.2[化学工程—无机化工] TB663[一般工业技术—制冷工程]