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Title: Exploring shear-induced segregation in controlled-velocity granular flows
Particle segregation in geophysical and industrial granular flows is typically driven by gravity and shear. While gravity-induced segregation is relatively well understood, shear-induced segregation is not. In particular, what controls segregation in the absence of gravity and the interplay between shearand gravity-driven segregation remain unclear. Here, we explore the shear-induced segregation force on an intruder particle in controlled-velocity granular flows where the shear profile is systematically varied. The shear-induced segregation force is found to be proportional to the shear rate gradient, which effectively pushes the large intruder from lower to higher shear rate regions. A scaling law is developed for the segregation force that is accurate over a wide range of overburden pressures and shear rates, and hence inertial numbers.  more » « less
Award ID(s):
Author(s) / Creator(s):
; ; ;
Aguirre, M.A.; Luding, S.; Pugnaloni, L.A.; Soto, R.
Date Published:
Journal Name:
EPJ Web of Conferences
Page Range / eLocation ID:
Medium: X
Sponsoring Org:
National Science Foundation
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