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A simulation study of the dynamics of a driven filament in an Aristotelian fluid

M. Cosentino Lagomarsino·F. Capuani·C. P. Lowe
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Abstract

We describe a method, based on techniques used in molecular dynamics, for simulating the inertialess dynamics of an elastic filament immersed in a fluid. The model is used to study the "one-armed swimmer". That is, a flexible appendage externally perturbed at one extremity. For small amplitude motion our simulations confirm theoretical predictions that, for a filament of given length and stiffness, there is a driving frequency that is optimal for both speed and efficiency. However, we find that to calculate absolute values of the swimming speed we need to slightly modify existing theoretical approaches. For the more realistic case of large amplitude motion we find that while the basic picture remains the same, the dependence of the swimming speed on both frequency and amplitude is substantially modified. For realistic amplitudes we show that the one armed swimmer is comparatively neither inefficient nor slow. This begs the question, why are there little or no one armed swimmers in nature?

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M. Cosentino Lagomarsino, F. Capuani, C. P. Lowe. 2002-08-06. A simulation study of the dynamics of a driven filament in an Aristotelian fluid. https://arxiv.org/abs/physics/0208022

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