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arXiv · 1511.06386

The effect of gait on swimming in viscoelastic fluids

Gwynn J. Elfring·Gaurav Goyal
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Abstract

In this paper, we give formulas for the swimming of simplified two-dimensional bodies in complex fluids using the reciprocal theorem. By way of these formulas we calculate the swimming velocity due to small-amplitude deformations on the simplest of these bodies, a two-dimensional sheet, to explore general conditions on the swimming gait under which the sheet may move faster, or slower, in a viscoelastic fluid compared to a Newtonian fluid. We show that in general, for small amplitude deformations, a speed increase can only be realized by multiple deformation modes in contrast to slip flows. Additionally, we show that a change in swimming speed is directly due to a change in thrust generated by the swimmer.

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Gwynn J. Elfring, Gaurav Goyal. 2016-04-19. The effect of gait on swimming in viscoelastic fluids. https://doi.org/10.1016/j.jnnfm.2016.04.005

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