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Updated: Jan 4, 2026

Fabricating High-viscosity Droplets using Microfluidic Capillary Device with Phase-inversion Co-flow Structure
Published on: April 17, 2018
Universality in the viscous-to-inertial coalescence of liquid droplets
Xi Xia1,2, Chengming He2, Peng Zhang3
1School of Mechanical Engineering, Shanghai Jiao Tong University, Minhang, Shanghai 200240, P. R. China.
Abstract:
We present a theory on the coalescence of 2 spherical liquid droplets that are initially stationary. The evolution of the radius of a liquid neck formed upon coalescence was formulated as an initial value problem and then solved to yield an exact solution without free parameters, with its 2 asymptotic approximations reproducing the well-known scaling relations in the inertially limited viscous and inertial regimes. The viscous-to-inertial crossover observed in previous research is also recovered by the theory, rendering the collapse of data of different viscosities onto a single curve.
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