Thinning dynamics of the liquid thread at different stages in a rectangular cross junction

Abstract

Flow regime maps are plotted and the universal transitional boundary of squeezing regime and dripping regime is gained when both inertial force and viscous force of the dispersed phase are considered. The neck thinning process within the rectangular channel is divided into three stages according to evolutions of the neck width: twodimensional shrinking stage, transitional stage, and collapsing stage. Influences of the flow rates of two phases and the dispersed viscosity on evolutions of the neck width at different stages are explored. Different relations between the neck width and the remaining time are found for the earlier two stages. At the third stage, two physical mechanisms are separated by the dispersed viscosity as the neck width decreases according to w n /W ~τ2/3 under the inertial regime for both water and 40% glycerol, while the neck width reduces linearly as w n ~2(0.0709σ/μ d )t r under the viscous regime for 55% glycerol.

Robust generation of monodisperse droplets using a microfluidic step emulsification device with triangular nozzle

“…5,6 Shear-based microfluidic approach is one of the most common way to produce monodispersed droplets, such as co-flow, 7 T-junction, 8,9 and flowfocusing. [10][11][12] In this kind of microfluidics, the shear force is critical in the evolution and breakup of interfaces. 13,14 The droplet size is mainly influenced by the change in flow rates of the fluids, and thus a small flow rate fluctuation can lead to the deterioration in monodispersity of droplets.…”

“…Monodispersed droplet generation is receiving a lot of attention in microfluidic technology 1 and industrial applications, such as food, 2 pharmaceutical, 3,4 cosmetic, and oil industries 5,6 . Shear‐based microfluidic approach is one of the most common way to produce monodispersed droplets, such as co‐flow, 7 T‐junction, 8,9 and flow‐focusing 10–12 . In this kind of microfluidics, the shear force is critical in the evolution and breakup of interfaces 13,14 .…”