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Phases of granular segregation in a binary mixture

Pedro M. Reis·Tim Sykes·Tom Mullin
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Abstract

We present results from an extensive experimental investigation into granular segregation of a shallow binary mixture in which particles are driven by frictional interactions with the surface of a vibrating horizontal tray. Three distinct phases of the mixture are established viz; binary gas (unsegregated), segregation liquid and segregation crystal. Their ranges of existence are mapped out as a function of the system's primary control parameters using a number of measures based on Voronoi tessellation. We study the associated transitions and show that segregation can be suppressed is the total filling fraction of the granular layer, $C$, is decreased below a critical value, $C_{c}$, or if the dimensionless acceleration of the driving, $γ$, is increased above a value $γ_{c}$.

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Pedro M. Reis, Tim Sykes, Tom Mullin. 2006-06-01. Phases of granular segregation in a binary mixture. https://doi.org/10.1103/physreve.74.051306

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