Adhesive forces in droplet kinetic friction

Glen McHale; Sara Janahi; Hernán Barrio-Zhang; Yaofeng Wang; Jinju Chen; Gary G. Wells; Rodrigo Ledesma-Aguilar

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arXiv · 2510.09642

Adhesive forces in droplet kinetic friction

Glen McHale·Sara Janahi·Hernán Barrio-Zhang·Yaofeng Wang·Jinju Chen·Gary G. Wells·Rodrigo Ledesma-Aguilar

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Abstract

Kinetic frictional forces resisting droplet motion often appear to be separate to surface wettability and adhesive forces. Here we show that such friction arises from a simple combination of the contact angle hysteresis and adhesive force. We show theoretically, and confirm using tilt angle experiments of droplets on liquid-like surfaces, the dependence of the coefficient of droplet-on-solid kinetic friction on system parameters. We also show that a molecular kinetic-type model can describe the observed non-linear velocity-force relationship. Our findings provide a fundamental understanding of the relationship between droplet-on-solid friction, and wettability and liquid adhesion.

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Glen McHale, Sara Janahi, Hernán Barrio-Zhang, Yaofeng Wang, Jinju Chen, Gary G. Wells, Rodrigo Ledesma-Aguilar. 2025-10-03. Adhesive forces in droplet kinetic friction. https://arxiv.org/abs/2510.09642

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