Numerical simulation on double emulsion formation in flow-focusing microchannel

Double emulsion formation in flow-focusing microchannel is numerically analyzed by using the volume-of-fluid method to track the interface motion with a focus on the drop formation regimes. Two distinct regimes, dripping and jetting, are presented, and the effects of the flow rates on double emulsion formation are analyzed. The results indicate that the outer fluid flow rate triggers the transition of drop formation regime and has influence on the drop size, however, increasing the flow rate of the middle fluid only introduce slight increase of outer drop size and its effect on the drop formation regime is not significant.