Dynamics of Vibrated Granular Monolayers

TL;DR

This study investigates the behavior of vibrated granular monolayers through simulations, revealing phase transitions from gas to clustered states and changes in particle motion and velocity distributions with varying excitation strengths.

Contribution

It provides new insights into the phase behavior and velocity distribution changes in vibrated granular monolayers at different excitation levels.

Findings

At high excitation, the system behaves as a gas with Gaussian velocity distributions.

Lowering excitation induces a transition to a phase with clusters and bimodal velocity distributions.

Below a critical excitation, the system exhibits a gas-cluster phase with immobile particle clusters and gas particles at specific energy states.

Abstract

We study statistical properties of vibrated granular monolayers using molecular dynamics simulations. We show that at high excitation strengths, the system is in a gas state, particle motion is isotropic, and the velocity distributions are Gaussian. As the vibration strength is lowered the system's dimensionality is reduced from three to two. Below a critical excitation strength, a gas-cluster phase occurs, and the velocity distribution becomes bimodal. In this phase, the system consists of clusters of immobile particles arranged in close-packed hexagonal arrays, and gas particles whose energy equals the first excited state of an isolated particle on a vibrated plate.