Enhancement of immiscible fluid mixing using passive micromixers to increase the performance of liquid-liquid extraction

This paper aims to simulate an immiscible two-phase flow in two-dimensional T-shaped, modified T-shaped, cross-shaped, and modified cross-shaped micromixers numerically. The effects of various parameters, including Capillary number, phase flow rate ratio, and channel width ratio, on the generation of droplets were studied. Also, modification of T-shaped and cross-shaped micromixers was proposed. The results reveal that equidistant tiny droplets are generated in the modified micromixers compared to ordinary geometry under the same conditions. Three types of squeezing regime, laminar regime, and jetting regime were observed in different values of the capillary number. It was also observed that the droplet size decreases with the increase in capillary number. Moreover, this study demonstrates that the multiphase flows in micro-devices are very sensitive to even small changes in the channel geometry.