Modeling microscopic swimmers at low Reynolds number

David J. Earl; C. M. Pooley; J. F. Ryder; Irene Bredberg; J. M. Yeomans

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arXiv · cond-mat/0701511

Modeling microscopic swimmers at low Reynolds number

David J. Earl·C. M. Pooley·J. F. Ryder·Irene Bredberg·J. M. Yeomans

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Abstract

We employ three numerical methods to explore the motion of low Reynolds number swimmers, modeling the hydrodynamic interactions by means of the Oseen tensor approximation, lattice Boltzmann simulations and multiparticle collision dynamics. By applying the methods to a three bead linear swimmer, for which exact results are known, we are able to compare and assess the effectiveness of the different approaches. We then propose a new class of low Reynolds number swimmers, generalized three bead swimmers that can change both the length of their arms and the angle between them. Hence we suggest a design for a microstructure capable of moving in three dimensions. We discuss multiple bead, linear microstructures and show that they are highly efficient swimmers. We then turn to consider the swimming motion of elastic filaments. Using multiparticle collision dynamics we show that a driven filament behaves in a qualitatively similar way to the micron-scale swimming device recently demonstrated by Dreyfus et al.

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David J. Earl, C. M. Pooley, J. F. Ryder, Irene Bredberg, J. M. Yeomans. 2007-01-22. Modeling microscopic swimmers at low Reynolds number. https://arxiv.org/abs/cond-mat/0701511

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