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arXiv · 1805.00267

Oscillations of confined fibers transported in microchannels

Mathias Nagel·Pierre-Thomas Brun·Helene Berthet·Anke Lindner·François Gallaire·Camille Duprat
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Abstract

We investigate the trajectories of rigid fibers as they are transported in a pressure-driven flow, at low Reynolds number, in shallow Hele Shaw cells. The transverse confinement and the resulting viscous friction on these elongated objects, as well as the lateral confinement (i.e. the presence of lateral walls), lead to complex fibers trajectories that we characterize with a combination of microfluidic experiments and simulations using modified Brinkman equations. We show that the transported fiber behaves as an oscillator for which we obtain and analyze a complete state diagram.

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Mathias Nagel, Pierre-Thomas Brun, Helene Berthet, Anke Lindner, François Gallaire, Camille Duprat. 2018-05-01. Oscillations of confined fibers transported in microchannels. https://doi.org/10.1017/jfm.2017.662

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