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arXiv · 1611.05847

An elastic two-sphere swimmer in Stokes flow

Babak Nasouri·Aditi Khot·Gwynn J. Elfring
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Abstract

Swimming at low Reynolds number in Newtonian fluids is only possible through non-reciprocal body deformations due to the kinematic reversibility of the Stokes equations. We consider here a model swimmer consisting of two linked spheres, wherein one sphere is rigid and the other an incompressible neo-Hookean solid. The two spheres are connected by a rod which changes its length periodically. We show that the deformations of the body are non-reciprocal despite the reversible actuation and hence, the elastic two-sphere swimmer propels forward. Our results indicate that even weak elastic deformations of a body can affect locomotion and may be exploited in designing artificial microswimmers.

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Babak Nasouri, Aditi Khot, Gwynn J. Elfring. 2017-03-05. An elastic two-sphere swimmer in Stokes flow. https://doi.org/10.1103/physrevfluids.2.043101

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