The investigation of the dynamics of a droplet traversing through constricted channels is an interesting field of research. In the present work, the motion and deformation of a neutrally buoyant droplet in planar constricted micro channels containing another immiscible fluid is studied computationally using an open-source finite-volume fluid flow solver, Gerris. The important non-dimensional parameters pertaining to such type of flow are — the Capillary number, which gives the relative importance of the viscous force over the surface tension force, the viscosity ratio between the dispersed and suspending medium and the ratio of the drop diameter to the channel height. Both symmetrical and asymmetrical constrictions are considered and results obtained are compared with a straight channel without any constriction. The parametric studies are conducted to study the effect of droplet size, viscosity ratio, Capillary number and presence of constriction in the channel. Depending on the parameters chosen, the drop extends to a maximum length as its front passes through the constriction and the deformation increases with the increase in number of constrictions. In the case of large drops, it is observed that the droplet disintegration rate increases in the presence of constrictions.

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