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arXiv · 2506.20116

Static friction of liquid marbles

Yui Takai·Kei Mukoyama·Pritam Kumar Roy·Guillaume Lagubeau·David Quéré·Samuel Poincloux·Timothée Mouterde
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Abstract

Liquid marbles, droplets coated with a granular layer, are highly mobile as particles prevent capillary adhesion to the substrate. Yet their coating creates a static rolling friction, which we measure and model. Motion requires shear within the shell so that it is governed mainly by the grain density. This density controls yielding via a logistic function emerging as the particle network approaches percolation and increasing rapidly at close packing. More broadly, our system offers a simple platform for probing granular-raft mechanics and measuring their effective surface tension.

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Yui Takai, Kei Mukoyama, Pritam Kumar Roy, Guillaume Lagubeau, David Quéré, Samuel Poincloux, Timothée Mouterde. 2025-06-25. Static friction of liquid marbles. https://arxiv.org/abs/2506.20116

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