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arXiv · 2306.08689

On the lack of influence of contact area on the solid-liquid lateral retention force

Rafael de la Madrid·Caleb Gregory·Huy Luong·Tyler Stuck
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Abstract

We experimentally show that, unlike the solid-solid frictional force, the solid-liquid retention force is determined by interactions at the triple line rather than over the solid-liquid contact area, as predicted by theory. We have prepared drops whose triple line enclosed a uniform surface, a hydrophobic island, and topographical inhomogeneities, and measured the same retention force for all three cases. We have also studied the retention force on drops whose initial triple line was non-circumferential and measured different retention forces for different shapes, also as predicted by theory. The experiments with non-circumferential drops provide (1) another way to show that the retention force is not proportional to the contact area, and (2) a manner to falsify a recent theory on drop depinning.

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Rafael de la Madrid, Caleb Gregory, Huy Luong, Tyler Stuck. 2023-06-14. On the lack of influence of contact area on the solid-liquid lateral retention force. https://arxiv.org/abs/2306.08689

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