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 as 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, $\gamma$, is increased above a value ${\gamma }_c$.

• Received 30 May 2006

DOI:https://doi.org/10.1103/PhysRevE.74.051306