Formation of Microdroplets in PMMA Microfluidic Device

This study presents the formation of uniform droplets in a T-shaped microfluidic device. Water has been used as a dispersed phase whereas oil (sunflower/canola) as a continuous phase. The microfluidic chip was fabricated on Poly methyl methacrylate (PMMA) material using a CNC machine. The flow rate of both phases was controlled using Laboratory-made syringe pumps. It was predicted that at a flow rate ratio of G=0.125 (G=ratio of dispersed phase to continuous phase), the spherical shaped droplets were observed to be formed. The shape changes from spherical to plug form at a higher value of G=1. The distance between two consecutive droplets, droplet detachment time and effect of the Capillary number on the advancing contact angle were studied. The fabricated microfluidic chip is demonstrated to be capable of generating uniform droplets with the advantage of actively controlled droplet size.