New insights into generation of highly controllable monodisperse high-throughput microdroplets in a T-junction microchannel with step structure

Abstract

With the development of droplet microfluidic technology, there are some problems in the current generation of droplets using microchannels, such as high cost, and difficulty in controlling the size of droplets and the generation frequency. This paper applies numerical simulation method to study T-junction microchannels. Studies have shown that the pressure difference in the T-junction microchannel and the viscous shear force of the continuous phase act as a driving force in the droplet formation process. The effective droplet diameter decreases as the Ca increases, and the generation frequency increases as Ca increases. Based on the level-set method, three T-junction microchannels with step structure at different positions are designed to study the problem of generating monodisperse high-throughput microdroplets. This paper achieves flexible control of droplet generation using three different designs. In the three designs, when the step position is in the middle, the generated droplet diameter is the smallest and the frequency is the fastest. Therefore, studies have shown that the step structure in the middle is the optimal solution for generating monodisperse high-throughput microdroplets.