Bidirectional Motion of Droplets on Gradient Liquid Infused Surfaces

Muhammad Subkhi Sadullah; Gaby Launay; Jayne Parle; Rodrigo Ledesma-Aguilar; Yonas Gizaw; Glen McHale; Gary Wells; Halim Kusumaatmaja

arXiv · 2004.10408

Bidirectional Motion of Droplets on Gradient Liquid Infused Surfaces

Muhammad Subkhi Sadullah·Gaby Launay·Jayne Parle·Rodrigo Ledesma-Aguilar·Yonas Gizaw·Glen McHale·Gary Wells·Halim Kusumaatmaja

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Abstract

We demonstrate spontaneous bidirectional motion of droplets on liquid infused surfaces in the presence of a topographical gradient, in which the droplets can move either toward the denser or the sparser solid fraction area. Our analytical theory explains the origin of this bidirectional motion. Furthermore, using both lattice Boltzmann simulations and experiments, we show that the key factor determining the direction of motion is the wettability difference of the droplet on the solid surface and on the lubricant film. The bidirectional motion is shown for various combinations of droplets and lubricants, as well as for different forms of topographical gradients.

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Muhammad Subkhi Sadullah, Gaby Launay, Jayne Parle, Rodrigo Ledesma-Aguilar, Yonas Gizaw, Glen McHale, Gary Wells, Halim Kusumaatmaja. 2020-04-22. Bidirectional Motion of Droplets on Gradient Liquid Infused Surfaces. https://arxiv.org/abs/2004.10408

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