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arXiv · 1901.02988

Pattern formation in a fully-3D segregating granular flow

Mengqi Yu·Paul B. Umbanhowar·Julio M. Ottino·Richard M. Lueptow
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Abstract

Segregation patterns of size-bidisperse particle mixtures in a fully-three-dimensional flow produced by alternately rotating a spherical tumbler about two perpendicular axes are studied over a range of particle sizes and volume ratios using both experiments and a continuum model. Pattern formation results from the interaction of size segregation with chaotic regions and non-mixing islands of the flow. Specifically, large particles in the flowing surface layer are preferentially deposited in non-mixing islands despite the effects of collisional diffusion and chaotic transport. The protocol-dependent structure of the unstable manifolds of the flow surrounding the non-mixing islands provides further insight into why certain segregation patterns are more robust than others.

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Mengqi Yu, Paul B. Umbanhowar, Julio M. Ottino, Richard M. Lueptow. 2019-01-10. Pattern formation in a fully-3D segregating granular flow. https://doi.org/10.1103/physreve.99.062905

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