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arXiv · 1907.06839

Universal optimal geometry of minimal phoretic pumps

Sebastien Michelin·Eric Lauga
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Abstract

Unlike pressure-driven flows, surface-mediated phoretic flows provide efficient means to drive fluid motion on very small scales. Colloidal particles covered with chemically-active patches with nonzero phoretic mobility (e.g. Janus particles) swim using self-generated gradients, and similar physics can be exploited to create phoretic pumps. Here we analyse in detail the design principles of phoretic pumps and show that for a minimal phoretic pump, consisting of 3 distinct chemical patches, the optimal arrangement of the patches maximizing the flow rate is universal and independent of chemistry.

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Sebastien Michelin, Eric Lauga. 2019-07-16. Universal optimal geometry of minimal phoretic pumps. https://doi.org/10.1038/s41598-019-46953-8

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