title: Cluster growth in driven granular gases.
abstract: We investigate numerically and theoretically the internal structures of a driven granular gas in cuboidal cell geometries. Clustering is reported and particles are classified as gaseous or clustered via a local packing fraction criterion based on a Voronoi tessellation. We observe that small clusters arise in the corners of the box, elucidating early reports of partial clustering. These aggregates have a condensation-like surface growth. When a critical size is reached, a structural transition occurs and all clusters merge together, leaving a hole in the center of the cell. This hole then becomes the new center of particle capture. Taking into account all structural modifications and defining a saturation packing fraction, we propose an empirical model for the cluster growth.
authors.affiliation: GRASP Laboratory, CESAM Research Unit, Physics Department, B5a, University of Liège, B-4000-Liège, Belgium.
authors.forename: Martial
authors.initials: M
authors.lastname: Noirhomme
authors.affiliation: GRASP Laboratory, CESAM Research Unit, Physics Department, B5a, University of Liège, B-4000-Liège, Belgium.
authors.forename: François
authors.initials: F
authors.lastname: Ludewig
authors.affiliation: GRASP Laboratory, CESAM Research Unit, Physics Department, B5a, University of Liège, B-4000-Liège, Belgium.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Vandewalle
authors.affiliation: GRASP Laboratory, CESAM Research Unit, Physics Department, B5a, University of Liège, B-4000-Liège, Belgium.
authors.forename: Eric
authors.initials: E
authors.lastname: Opsomer