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arXiv · 2410.20821

Transition time of a bouncing drop

Yahua Liu·Seyed Ali Hosseini·Cong Liu·Milo Feinberg·Benedikt Dorschner·Zuankai Wang·Ilya Karlin
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Abstract

Contact time of bouncing drops is one of the most essential parameters to quantify the water-repellency of surfaces. Generally, the contact time on superhydrophobic surfaces is known to be Weber number-independent. Here, we probe an additional characteristic time, \emph{transition time} inherent in water drop impacting on superhydrophobic surfaces, marking a switch from a predominantly lateral to an axial motion. Systematic experiments and numerical simulations show that the transition time is also Weber number-independent and accounts for half the contact time. Additionally we identify a Weber-independent partition of volume at the maximum spreading state between the rim and lamella and show that the latter contains 1/4 of the total volume of the drop.

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Yahua Liu, Seyed Ali Hosseini, Cong Liu, Milo Feinberg, Benedikt Dorschner, Zuankai Wang, Ilya Karlin. 2024-10-28. Transition time of a bouncing drop. https://arxiv.org/abs/2410.20821

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