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Updated: Jan 21, 2026

The Intra-Aortic Balloon Pump
Published on: February 5, 2021
Universal optimal geometry of minimal phoretic pumps
Sébastien Michelin1, Eric Lauga2
1LadHyX - Département de Mécanique, Ecole Polytechnique - CNRS, Institut Polytechnique de Paris, 91128, Palaiseau, France. sebastien.michelin@ladhyx.polytechnique.fr.
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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