增压输送过程中卧式贮罐液氢温度分层研究

Investigation on thermal stratification of liquid hydrogen in a horizontal liquid hydrogen tank in pressurization feed process

分析了大型卧式液氢贮罐增压输出过程中低温介质传热数学模型,揭示了贮罐内液氢温度分布规律,说明了液氢温度分层形成的原因及过程,给出了输出液氢品质保障方法。研究表明:大型卧式液氢贮罐输出过程中液氢温度分布可用修正后的半无限大平板非稳态导热方程描述;在增压压力一定情况下,热液层厚度随着输送时间的增加而增大,且热液层厚度及其温度分布受卧式贮罐截面形状影响;液氢贮罐输出品质与贮罐内热液层厚度密切相关,可通过计算热液层厚度从而确定贮罐留底余量的方法,保证贮罐输出品质。

A heat transfer mathematical model of liquid hydrogen in a large scale horizontal liquid hydrogen tank in pressurization feed process was analyzed,and distribution of temperature field was depicted.The appearance and cause of thermal stratification phenomenon were analyzed.A method for guaranteeing the liquid hydrogen output temperature in a large scale tank was offered.The investigation results indicate that the modified semi-infinite slab unsteady heat conduction equation could describe the temperature profiles of liquid hydrogen in the tank approximately.The warm liquid layer thickness increased as output time increased,and the thickness and its temperature profiles were affected by the tank shape.The liquid hydrogen output temperature tightly correlated with warm liquid layer thickness,and the output temperature could be guaranteed by calculating the liquid hydrogen remnant in the tank.