CIESC Journal ›› 2022, Vol. 73 ›› Issue (6): 2563-2572.DOI: 10.11949/0438-1157.20220052

• Fluid dynamics and transport phenomena • Previous Articles     Next Articles

Liquid-liquid two-phase flow and mesoscale effect in parallel microchannels

Zhongdong WANG(),Chunying ZHU,Youguang MA,Taotao FU()   

  1. State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
  • Received:2022-01-11 Revised:2022-04-07 Online:2022-06-30 Published:2022-06-05
  • Contact: Taotao FU

并行微通道内液液两相流及介尺度效应

王忠东(),朱春英,马友光,付涛涛()   

  1. 天津大学化工学院,化学工程联合国家重点实验室,天津 300072
  • 通讯作者: 付涛涛
  • 作者简介:王忠东(1999—),男,硕士研究生,wzdtju@163.com
  • 基金资助:
    国家自然科学基金项目(21878212)

Abstract:

The flow patterns of liquid-liquid two-phase flow in T-shaped parallel microchannels are studied by using a high-speed camera system. The glycerol-water solution is used as the dispersed phase, and silicone oil with 5% Dowsil as the continuous phase. Four flow patterns of slug flow, droplet flow, annular flow and parallel flow are observed in parallel channels under different two-phase flow conditions. The diagram of flow patterns is constructed with the flow rates of the two-phase as the coordinate axes, and the transition lines of flow patterns are obtained. The influences of the viscosity of the continuous phase on the flow patterns and their transitions are investigated. As the viscosity of the continuous phase increases, the transition lines of flow patterns move downward, the region of the slug flow becomes smaller, and the region of the droplet flow becomes larger. The flow patterns of the droplet group in cavity are studied, and the mesoscale concept is used to analyze the effects of the behavior of the droplet group in cavity on the flow distribution. Four flow patterns in cavity are observed under different two-phase flow conditions, the flow patterns of the droplet group in cavity are mainly affected by the flow ratio of the two phases. The flow distribution is mainly controlled by the fluid resistance of the parallel channels and the mesoscale structure of the cavity. The influence of flow ratio of the two phases on flow distribution is studied and the dominant factor of flow distribution corresponding to different operating conditions is obtained. When the two-phase flow ratio is small, the flow distribution is dominated by the fluid resistance of the downstream channel, while when the two-phase flow ratio is large, it is dominated by the dynamics of the droplet population in the back cavity.

Key words: parallel microchannels, two-phase flow, distributions, mesoscale

摘要:

使用高速摄像仪研究了T形并行微通道液液两相流的流型。以甘油-水溶液为分散相、含5%(质量分数)道康宁的硅油为连续相,下游通道中观察到了塞状流、液滴流、环状流和并行流4种流型,绘制了流型图及流型转变线。研究了后空腔中液滴群的形态,运用介尺度概念分析了后空腔中液滴群的行为对流量分配的影响。观察到后空腔中液滴群的挤压、松散、有序排列和并行排列等4种形态,不同形态的转变主要受两相流量比的控制。研究了两相流量比对并行微通道内流量分配的影响,以及分析了不同操作条件下影响流量分配的主导因素。在两相流量比较小时,流量分配由下游通道的流体阻力主导,而两相流量比较大时由后空腔内液滴群动力学主导。

关键词: 并行微通道, 两相流, 分布, 介尺度

CLC Number: