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arXiv · 1601.02065

Liquid jet rebound upon impact on a soft gel

Dan Daniel·Xi Yao·Joanna Aizenberg
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Abstract

A liquid jet can stably bounce off a sufficiently soft gel, by following the contour of the dimple created upon impact. This new phenomenon is insensitive to the wetting properties of the gels and was observed for different liquids over a wide range of surface tensions, $\gamma$ = 24--72 mN/m. In contrast, other jet rebound phenomena are typically sensitive to $\gamma$: jet rebounds off a hard solid (e.g. superhydrophobic surface) or another liquid are possible only for high and low $\gamma$ liquids, respectively. This is because an air layer must be stabilized between the two interfaces. For a soft gel, no air layer is necessary and jet rebound remains stable even when there is direct liquid-gel contact.

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Dan Daniel, Xi Yao, Joanna Aizenberg. 2016-01-09. Liquid jet rebound upon impact on a soft gel. https://doi.org/10.1103/physrevlett.120.028006

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