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arXiv · 2105.09308

Comment on "Directed motion of spheres by unbiased driving forces in viscous fluids beyond the Stokes' law regime"

Pedro J. Martínez·Ricardo Chacón
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Abstract

In a recent paper by Casado-Pascual [Phys. Rev. E \textbf{97}, 032219 (2018)], directed motion of a sphere immersed in a viscous fluid and subjected to zero-average biharmonic forces is studied. The author explains the dependence on the relative amplitude of the two harmonic components of the average terminal velocity from the perspective of a general formalism. In this Comment, this explanation is shown to be in general incorrect, while the theory of ratchet universality together with the vibrational mechanics approach provide a satisfactory explanation of major aspects of the observed phenomena.

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Pedro J. Martínez, Ricardo Chacón. 2021-05-18. Comment on "Directed motion of spheres by unbiased driving forces in viscous fluids beyond the Stokes' law regime". https://arxiv.org/abs/2105.09308

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