Investigating the Effect of Geometric and Physical Parameters on Droplet Formation in Cross Junction Microchannel

Droplet-based microfluidics is an emerging branch that has a variety of applications in the fields of drug delivery, biotechnology and material science. Droplet size and frequency control are essential for microfluidic lab-on-chip. In this paper, the merged droplet formation in a cross junction is studied by three-dimensional numerical simulation using level-set method and finite element method. There are eight significant parameters in this geometry, namely the width of the main channel, the width of the side channel, the thickness of the microchannel, the angle between two-phase, the contact angle between fluid and the wall of the microchannel, the viscosity of the continuous phase, the interfacial tension and the flow rate ratio. The results of this paper show that geometric parameters and the flow rate ratio of two fluids have more effect on the effective diameter of the droplet and its frequency. This work helps researchers to concentrate on these parameters in practical applications.