类文丘里十字型流道中的液滴流态分析

Analysis of droplet flow regimes in venturi-like flow focusing channels

目的:研究类文丘里十字型流道中液滴流态形成原因。方法:采用流体体积法以及二维模型,对类文丘里十字型流道中液滴生成进行数值模拟。结果:通过改变毛细数和流量比,在类文丘里十字型流道中观察到三种典型流态,即挤压态、滴落态和射流态。各流态之间的形貌变化和压力呈现出不同规律。结论:毛细数和流量比的变化会改变液滴生成过程中的主导力,进而改变液滴生成流态。

Aims:This paper aims to study the causes of droplet flow regimes in venturi-like flow focusing channels.Methods:Numerical simulations of droplet generation in venturi-like flow focusing channels were performed using the volume of the fluid method and a two-dimensional model.Results:By varying the capillary number and the flow rate ratio,three typical flow regimes,i.e.,squeezing,dripping,and threading,were observed in the venturi-like flow focusing channel.The morphological changes and pressure between the flow regimes showed different patterns.Conclusions:Changes in the capillary number and the flow rate ratio change the dominant forces in the droplet generation process,thus changing the droplet generation flow regime.