液氢加注系统竖直管道内Taylor气泡的行为特性

Research on Taylor bubble's behavior in vertical tube of liquid hydrogen loading system

针对液氢加注系统竖直管道内气液两相流实验化困难的问题,运用建模仿真的方法建立了竖直管道内Taylor气泡的运动模型,对Taylor气泡的形成过程、大小以及充分发展的Taylor气泡上升速度进行了研究。采用VOF方法对气液两相的交界面进行追踪,并引入CSF模型对两相间的表面张力进行计算。仿真结果表明:Taylor气泡是由弥散的小气泡聚合而成,根据泡状流向弹状流转变得出的Taylor气泡的临界长度比处于发展中的Taylor气泡长度要小,充分发展的Taylor气泡基本上以0.226 5 m/s的速度匀速上升。

Because of the experimental difficulty of two-phase flow in a vertical tube for liquid hydrogen loading systems,a Taylor bubble movement model in vertical tube were established using modeling and simulation methods.The formation process,size and rising velocity of Taylor bubble fully developed were studied.VOF method was used to track the interface of two-phase flow and CSF model was introduced to calculate the surface tension between two phases.Simulation results show that Taylor bubble is polymerized from the small dispersed bubbles,the critical length of the Taylor bubble when the bubbly flow changing to slug flow is smaller than the Taylor bubble in the development,Taylor bubble fully developed is basically increasing in the uniform rate of 0.226 5 m/s.