Order-disorder transition in swirled granular disks

Abstract

We study the order-disorder transition of horizontally swirled dry and wet granular disks by means of computer simulations. Our systematic investigation of the local order formation as a function of amplitude and period of the external driving force shows that a large cluster of hexagonally ordered particles forms for both dry and wet granular particles at intermediate driving energies. Disordered states are found at small and large driving energies. Wet granular particles reach a higher degree of local hexagonal order, with respect to the dry case. For both cases we report a qualitative phase diagram showing the amount of local order at different state points. Furthermore we find that the transition from hexagonal order to a disordered state is characterised by the appearance of particles with square local order.

Stratification in binary colloidal polymer films: experiment and simulations

“…Any mistakes, such as missed particles or inaccurate selection of a particle, were corrected manually. The local symmetry of the particles was calculated using a two-dimensional version 48 of the q 6 orientation bond order parameter. 49 The type of local symmetry of a particle is determined by looking at the distance between, and the orientations of, the neighbouring particles.…”

Minimal model for dynamic bonding in colloidal transient networks

“…A similar model was proposed for wet granular particles, i.e. the minimal capillary model [31,32]. For wet granular matter dissipative dynamics are considered in molecular dynamics simulations for the collisions, and the interaction between the grains due to capillary bridges is modeled by a constant force.…”