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arXiv · 0811.2918

Depinning of three-dimensional drops from wettability defects

Ph. Beltrame·P. Hänggi·U. Thiele
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Abstract

Substrate defects crucially influence the onset of sliding drop motion under lateral driving. A finite force is necessary to overcome the pinning influence even of microscale heterogeneities. The depinning dynamics of three-dimensional drops is studied for hydrophilic and hydrophobic wettability defects using a long-wave evolution equation for the film thickness profile. It is found that the nature of the depinning transition explains the experimentally observed stick-slip motion.

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Ph. Beltrame, P. Hänggi, U. Thiele. 2008-11-18. Depinning of three-dimensional drops from wettability defects. https://doi.org/10.1209/0295-5075/86/24006

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