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arXiv · 0806.4457

Soft swimming: Exploiting deformable interfaces for low-Reynolds number locomotion

Renaud Trouilloud·Tony S. Yu·A. E. Hosoi·Eric Lauga
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Abstract

Reciprocal movement cannot be used for locomotion at low-Reynolds number in an infinite fluid or near a rigid surface. Here we show that this limitation is relaxed for a body performing reciprocal motions near a deformable interface. Using physical arguments and scaling relationships, we show that the nonlinearities arising from reciprocal flow-induced interfacial deformation rectify the periodic motion of the swimmer, leading to locomotion. Such a strategy can be used to move toward, away from, and parallel to any deformable interface as long as the length scales involved are smaller than intrinsic scales, which we identify. A macro-scale experiment of flapping motion near a free surface illustrates this new result.

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Renaud Trouilloud, Tony S. Yu, A. E. Hosoi, Eric Lauga. 2008-06-27. Soft swimming: Exploiting deformable interfaces for low-Reynolds number locomotion. https://doi.org/10.1103/physrevlett.101.048102

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