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arXiv · 1207.2635

Symmetric and Asymmetric Coalescence of Drops on a Substrate

J. F. Hernandez-Sanchez·L. A. Lubbers·A. Eddi·J. H. Snoeijer
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Abstract

The coalescence of viscous drops on a substrate is studied experimentally and theoretically. We consider cases where the drops can have different contact angles, leading to a very asymmetric coalescence process. Side view experiments reveal that the "bridge" connecting the drops evolves with self-similar dynamics, providing a new perspective on the coalescence of sessile drops. We show that the universal shape of the bridge is accurately described by similarity solutions of the one-dimensional lubrication equation. Our theory predicts a bridge that grows linearly in time and stresses the strong dependence on the contact angles. Without any adjustable parameters, we find quantitative agreement with all experimental observations.

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J. F. Hernandez-Sanchez, L. A. Lubbers, A. Eddi, J. H. Snoeijer. 2012-07-11. Symmetric and Asymmetric Coalescence of Drops on a Substrate. https://doi.org/10.1103/physrevlett.109.184502

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