Effect of Inlet Angle and Flow Rate Ratio of Droplet Generation in Modified T-Junction Microchannel: A Numerical Study

Microfluidics represents one of the most rapidly evolving areas of study within the broader discipline of fluid mechanics. The manipulation of the fluid within the microchannel is achieved through the utilization of precise volume control. A significant area of investigation within this rapidly expanding field is the study of droplets between two immiscible fluids within the microchannel. The T-junction microchannel is a geometry that is widely used in microfluidics research. This research employed a two-dimensional simulation using COMSOL Multiphysics software to model droplet generation in a modified T-junction channel with varying flow rates and geometries. The flow rate ratio (Qr) was varied between 0.5 to 0.08, and the inlet angle of dispersed phase of the microchannel was also varied, 15°, 90°, and 165°, to investigate the effect of the geometry. The results demonstrated that as the flow rate ratio increased, the average droplet diameter increased from 102.66 μm to 195.38 μm, while the number of generated droplets decreased from 23 to 3 droplets in one second. It also shows that inlet angle of 90° can generate the highest number of droplets with 23 droplets in one second with the smallest average diameter equals to 102.66 μm.