Distribution of liquid-liquid two-phase flow and droplet dynamics in asymmetric parallel microchannels

The numbering-up of microchannels in parallel is usually engineered to achieve high-throughput production of droplets, and the flow distribution of fluids and uniformity of droplets in parallel microchannels are core issues for droplet formation. In this work, the distribution of liquid-liquid two-phase flow and droplet dynamics in asymmetric parallel microchannels are investigated by using a high speed camera, and the factors affecting the stability and uniformity of droplets are explored. The dynamic behavior of droplet swarm in the rear cavity and its feedback effect on droplet generation at T-junctions are revealed. The microfluidic devices with various configurations are designed to investigate its effects on flow distribution. In addition, based on the principle of hydrodynamic resistance for the liquid-liquid two-phase flow in microchannels, the prediction for the distri-bution of liquid-liquid two-phase flow under slug flow is proposed.