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arXiv · 1508.04255

Hydrodynamic oscillations and variable swimming speed in squirmers close to repulsive walls

Juho S. Lintuvuori·Aidan T. Brown·Kevin Stratford·Davide Marenduzzo
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Abstract

We present a lattice Boltzmann study of the hydrodynamics of a fully resolved squirmer, radius R, confined in a slab of fluid between two no-slip walls. We show that the coupling between hydrodynamics and short-range repulsive interactions between the swimmer and the surface can lead to hydrodynamic trapping of both pushers and pullers at the wall, and to hydrodynamic oscillations in the case of a pusher. We further show that a pusher moves significantly faster when close to a surface than in the bulk, whereas a puller undergoes a transition between fast motion and a dynamical standstill according to the range of the repulsive interaction. Our results critically require near-field hydrodynamics; they further suggest that it should be possible to control density and speed of squirmers at a surface by tuning the range of steric and electrostatic swimmer-wall interactions.

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Juho S. Lintuvuori, Aidan T. Brown, Kevin Stratford, Davide Marenduzzo. 2015-08-18. Hydrodynamic oscillations and variable swimming speed in squirmers close to repulsive walls. https://arxiv.org/abs/1508.04255

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