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arXiv · 1108.1129

Ultrafast Interference Imaging of Air in Splashing Dynamics

Michelle M. Driscoll·Sidney R. Nagel
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Abstract

A drop impacting a solid surface with sufficient velocity will emit many small droplets creating a splash. However, splashing is completely suppressed if the surrounding gas pressure is lowered. The mechanism by which the gas affects splashing remains unknown. We use high-speed interference imaging to measure the air beneath all regions of a spreading viscous drop as well as optical absorption to measure the drop thickness. Although an initial air bubble is created on impact, no significant air layer persists until the time a splash is created. This suggests that splashing in our experimentally accessible range of viscosities is initiated at the edge of the drop as it encroaches into the surrounding gas.

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Michelle M. Driscoll, Sidney R. Nagel. 2011-08-04. Ultrafast Interference Imaging of Air in Splashing Dynamics. https://doi.org/10.1103/physrevlett.107.154502

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