Deformation and breakup of droplets in a double T-junction microdisperser with double input of the continuous phase

Abstract

Droplet dynamics at double T-junction microdisperser are usually occurred in multiphase flow and complex fluids within microfluidics and microreactors. However, the mechanism of droplet dynamics in double T-junction microdisperser with the double input of the continuous phase remains unclear. In this article, the deformation and breakup of droplets in double T-junction microdisperser is experimentally studied with the double input of the continuous phase. Various flow patterns are observed for the dynamics of droplets. The droplet deformation is analyzed and discussed, and a prediction formula for the maximum droplet deformation is proposed. In addition, the breakup dynamics of droplets are studied systematically. The breakup of the droplet can be divided into squeezing stage, transition stage and pinch-off stage. The influence of the capillary number and the viscosity ratio of both phases on each stage of the droplet breakup are discussed. Finally, it is found that in the transition zone between the deformation and breakup of droplets, the tail of a droplet is often accompanied by corrugated filaments, and the filament breakage presents either tip streaming or self-similar fractures.