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arXiv · 2309.13273

General model for segregation forces in flowing granular mixtures

Yifei Duan·Lu Jing·Paul B. Umbanhowar·Julio M. Ottino·Richard M. Lueptow
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Abstract

Particle segregation in dense flowing size-disperse granular mixtures is driven by gravity and shear, but predicting the associated segregation force due to both effects has remained an unresolved challenge. Here, a model of the combined gravity- and kinematics-induced segregation force on a single intruder particle is integrated with a model of the concentration dependence of the gravity-induced segregation force. The result is a general model of the net particle segregation force in flowing size-bidisperse granular mixtures. Using discrete element method simulations for comparison, the model correctly predicts the segregation force for a variety of mixture concentrations and flow conditions in both idealized and natural shear flows.

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Yifei Duan, Lu Jing, Paul B. Umbanhowar, Julio M. Ottino, Richard M. Lueptow. 2023-09-23. General model for segregation forces in flowing granular mixtures. https://doi.org/10.1017/jfm.2024.483

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