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arXiv · 2302.00073

Viscosity ratio across interfaces controls the stability and self-assembly of microrollers

Blaise Delmotte
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Abstract

We investigate the individual and collective dynamics of torque-driven particles, called microrollers, near fluid-fluid interfaces. We find that the viscosity ratio across the interface controls the speed and direction of the particles, their relative motion, the growth of a fingering instability, and the self-assembled motile structures that emerge from it. By combining theory and large scale numerical simulations, we show how the viscosity ratio across the interface governs the long-range hydrodynamic interactions between particles and thus their collective behavior.

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Blaise Delmotte. 2023-06-16. Viscosity ratio across interfaces controls the stability and self-assembly of microrollers. https://doi.org/10.1103/physrevfluids.8.l062302

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