Drop impact on a flexible fiber

Emilie Dressaire; Alban Sauret; François Boulogne; Howard A. Stone

doi:10.1039/c5sm02246k

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arXiv · 1510.01489

Drop impact on a flexible fiber

Emilie Dressaire·Alban Sauret·François Boulogne·Howard A. Stone

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Abstract

When droplets impact fibrous media, the liquid can be captured by the fibers or contact then break away. Previous studies have shown that the efficiency of drop capture by a rigid fiber depends on the impact velocity and defined a threshold velocity below which the drop is captured. However, it is necessary to consider the coupling of elastic and capillary effects to achieve a greater understanding of the capture process for soft substrates. Here, we study experimentally the dynamics of a single drop impacting on a thin flexible fiber. Our results demonstrate that the threshold capture velocity depends on the flexibility of fibers in a non-monotonic way. We conclude that tuning the mechanical properties of fibers can optimize the efficiency of droplet capture.

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Emilie Dressaire, Alban Sauret, François Boulogne, Howard A. Stone. 2015-10-06. Drop impact on a flexible fiber. https://doi.org/10.1039/c5sm02246k

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