Numerical simulation of influence parameters during droplet generation in a microfluidic T-junction

Droplets had a significant advantage that each droplet could be regarded as an individual chemical reactor. However, the microchip for droplets generation was very difficult to design. Numerical simulation was done in order to provide a theoretical basis for microchip design. This paper described a three-dimensional numerical simulation on droplets behavior in a microfluidic T-shaped based on volume-of-fluid (VOF) model. The wetting property, the velocity and viscosity of continuous phase, the surface tension between two phases and the size of microchannel had been analyzed, which impacted the droplets´ behavior. Droplets can be generated when the contact angle was set from 0 degree to 90 degrees. With the velocity and viscosity of continuous phase increasing, droplets diameter would decrease gradually. The diameter of droplets increased according to the improvement of the surface tension between two phases. The droplets diameter was found to exhibit a linear dependence on the microchannel size. This work would contribute to the design of droplet microchips for better biochemical analysis, pharmaceuticals and so on.