Shaping Segregation: Convexity vs. Concavity

TL;DR

This paper demonstrates that altering the geometry of rotating containers with convex and concave shapes can significantly control and enhance segregation in granular systems, with potential applications in particle processing.

Contribution

It introduces a novel drum design that uses container geometry to manipulate segregation, achieving a tenfold increase in axial segregation rate.

Findings

Convex and concave geometries influence segregation patterns.

Rotational segregation can be controlled by container shape.

Enhanced axial segregation rate by an order of magnitude.

Abstract

Controlling segregation is both a practical and a theoretical challenge. In this Letter we demonstrate a manner in which rotation-induced segregation may be controlled by altering the geometry of the rotating containers in which granular systems are housed. Using a novel drum design comprising concave and convex geometry, we explore a means by which radial size-segregation may be used to drive axial segregation, resulting in an order of magnitude increase in the axial segregation rate. This finding, and the explanations provided of its underlying mechanisms, could lead to radical new designs for a broad range of particle processing applications.