矩形通道弹状流液膜特性

摘要

为了深入探究矩形通道内弹状流机理，利用高速摄像系统，对矩形通道（3．25 mm×40 mm）内弹状流进行了可视化研究。实验中发现，泰勒气泡长度LT随分气相雷诺数ReG近似线性增长，但随着分液相雷诺数ReL增加，LT的增长速率减小。液膜脱离泰勒气泡时厚度δf随ReG增加而减小并趋于稳定，随ReL增加而增大。δf主要由ReG、ReL和LT决定；LT≥150 mm时，δf趋于稳定。液膜脱离泰勒气泡时速度Vf随ReL增加而增大。在低ReL时，Vf方向向下并随ReG增加而减小；当ReL≥9102时，液膜始终向上运动，Vf随ReG变化较小，主要受ReL影响。通过数据回归分别得到了LT、δf和液膜相对脱离速度Vfr计算关联式，其与实验数据符合相对较好。%In order to investigate the mechanism of slug flow, visualized experiments were conducted by using a high speed video camera system in a rectangular channel (3.25 mm×40 mm). It was found that the Taylor bubble length LT increases almost linearly with the increasing of gas phase Reynolds numbers ReG, while its increase rate decrea⁃ses with the increasing of liquid phase Reynolds numbers ReL . The liquid film separating thicknessδf decreases with increasing of ReGand approximates to constant when it varies inversely with ReL. The ReG and ReLas well as the LT have significant influence onδf. For LT≥150 mm, theδf approximates to constant. The liquid film separating veloc⁃ity Vf increases with increasing of ReL. For low ReL, Vf is downward and decreases with increasing of ReG. When ReL≥9 102, the film always moves upward, the ReG has weak effect on Vf and Vf is mainly determined by ReL. The computational correlations of LT,δf and liquid film separating velocity relative to Taylor bubble Vfr are proposed ac⁃cording to data fitting, respectively. The correlations showed relatively good agreement with the experimental data.