过冷液氧增压排液过程数值模拟研究

Numerical investigation on pressurization discharge of subcooled liquid oxygen

为探究大容积贮箱中过冷液氧增压排液过程的热力学特性,基于流体体积法(VOF)和蒸发冷凝模型,构建了过冷液氧排出过程的数值模型。采用文献的实验数据验证了数值模型的准确性,并开展了变流量进气增压排液过程的罐内流场特性分析。研究结果表明,过冷液氧排出过程蒸发冷凝对气枕压降影响显著,采用变流量进气增压的方案能够较好地保持气枕压力稳定,使得气枕压力在3%以内波动。排液过程中,过冷液氧先升温明显,增压随着排液进行,贮箱气枕区域会出现涡状流,气体温度在水平方向有一定波动。

A numerical model based on the Volume of Fluids and evaporation-condensation algorithm was built to investigate the thermodynamic behavior of pressurization discharge with subcooled liquid oxygen in a large horizontal tank.The numerical model was verified by the experimental data from the literature.Accordingly,the effects of varying inlet gas mass flow rate on the performance of pressurization discharge were studied.The numerical results shows that evaporation and condensation significantly affect the pressure drop of the ullage.Varying inlet gas mass flow rate could help weaken the fluctuation of the ullage pressure by 3%.Besides,it reveals that the subcooled liquid oxygen experiences an obvious temperature rise.Vortex occurs in the ullage region,leading to the temperature variation in the horizontal direction.The numerical results could provide a reference for the design of the charging system of the subcooled liquid oxygen.