Relative energy dissipation-induced effective attraction in granular mixture

This paper presents the investigation of the clustering of the intruders in a vertically vibrated granular bed by means of event-driven simulations. The results indicate that the position of intruders in the vertical direction is not a key factor for their aggregation. Energy dissipation of the intruders and host particles are calculated in the process of intruder-host and host–host collisions. The relative energy dissipation of the intruders to that of the host particles is obtained. We find that clustering of the intruders happens when the relative energy dissipation is negative. The conclusion is verified when the restitution coefficient, density and diameter of the intruders are varied.