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arXiv · 2107.06958

Striped Patterns in Radially Driven Suspensions with Open Boundaries

Mahdieh Mohammadi·Maniya Maleki·Adam Wysocki·M. Reza Shaebani
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Abstract

We study the motion of radially driven fluid-immersed particles in a novel Hele-Shaw cell with open boundaries. The initially uniform suspension forms a striped pattern within a specific range of horizontal oscillation frequencies and for sufficiently large amplitudes. We observe that the initial coarsening dynamics of the stripes gradually slows down and the pattern reaches a steady state after a few minutes. The distance between the stripes in the steady state exhibits an exponentially saturating increase with increased oscillation amplitude or frequency. The width of the stripes decreases as a power-law with the frequency while its amplitude dependence follows a logistic function. We propose a mechanism -- based on the interplay between shear stress, hydrodynamic interactions, and frictional forces -- to link the structural characteristics of the stripes to the properties of the oscillatory external drive.

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Mahdieh Mohammadi, Maniya Maleki, Adam Wysocki, M. Reza Shaebani. 2021-10-30. Striped Patterns in Radially Driven Suspensions with Open Boundaries. https://doi.org/10.1063/5.0065801

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