Effects of topological changes in microchannel geometries on the asymmetric breakup of a droplet

Tuning the Splitting Behavior of Droplet in a Bifurcating Channel through Wettability–Capillarity Interaction

“…They reported critical conditions where the flow physics can significantly alter with the droplet size or strength of the surface tension force. Thereafter, Zheng et al 55 analyzed the effect of channel topology on the symmetric and asymmetric breakup of a droplet by varying the angle of the bifurcating channel. They found that the angle of the bifurcating channel significantly influences the critical capillary number, splitting time, splitting zone, and generation of satellite droplets.…”

“…Chen et al 48 also found that the VOF method effectively captures the legible interface of oil and water during their flow through T-junction. Zheng et al 55 also successfully used the VOF model to simulate three-dimensional droplet generation, breakup, and merging in microchannel with a high accuracy.…”

“…To benefit some of the major areas such as droplet mixing, drug transport, , and droplet-based logics, researchers have performed experimental, − numerical, , and analytical , investigations to understand the effect of individual factors along with the nature of confinement offered by geometrical configuration of the channel in delineating the droplet splitting mechanism. In this context, investigations on the phenomenon of droplet splitting were performed in different channel configurations such as cross-flow junctions, ,− co-flow junctions, , flow-focusing devices, , and bifurcating channels. − As depicted in the aforementioned studies, the generation of droplets and the change in their morphology thereafter originate from the capillary (Rayleigh–Plateau) instability resulting from the competing forces of viscosity and interfacial tension so as to end up with minimum interfacial area. In agreement with this reason, researchers have found droplets passing through a single inlet with double-outlet T-junction to either split or nonsplit into daughter droplets. ,,− Chen et al established the reason behind splitting and nonsplitting of droplets in T-junction and concluded the relative dominance of surface tension represented by capillary number and relative droplet length to be the key determinants.…”

“…In this context, investigations on the phenomenon of droplet splitting were performed in different channel configurations such as cross-flow junctions, ,− co-flow junctions, , flow-focusing devices, , and bifurcating channels. − As depicted in the aforementioned studies, the generation of droplets and the change in their morphology thereafter originate from the capillary (Rayleigh–Plateau) instability resulting from the competing forces of viscosity and interfacial tension so as to end up with minimum interfacial area. In agreement with this reason, researchers have found droplets passing through a single inlet with double-outlet T-junction to either split or nonsplit into daughter droplets. ,,− Chen et al established the reason behind splitting and nonsplitting of droplets in T-junction and concluded the relative dominance of surface tension represented by capillary number and relative droplet length to be the key determinants. Different types of breakup of droplets were captured, and a critical capillary number was determined to distinguish the splitting and nonsplitting regimes.…”

“…To delve deep into a parametric regime that may not be easily addressed within typical experimental constraints, researchers adopted different computational approaches to understand the dynamics of droplet splitting. The pertinent methodologies include lattice Boltzmann method (LBM), volume of fluid (VOF), ,, and phase field . It has been established that among the various multiphase simulation approaches, the VOF method holds the advantage of effectively capturing the interface.…”