Electrostatically-Driven Granular Media: Phase Transitions and Coarsening

TL;DR

This paper investigates how electrostatic forces induce phase transitions and coarsening in granular media, revealing hysteresis, cluster formation, and coagulation through experiments and simulations.

Contribution

It provides the first combined experimental and theoretical analysis of electrostatically driven phase transitions and cluster coarsening in granular materials.

Findings

Hysteretic first order phase transition observed

Spontaneous cluster formation and coarsening documented

Qualitative agreement between experiments and simulations

Abstract

We report the experimental and theoretical study of electrostatically driven granular material. We show that the charged granular medium undergoes a hysteretic first order phase transition from the immobile condensed state (granular solid) to a fluidized dilated state (granular gas) with a changing applied electric field. In addition we observe a spontaneous precipitation of dense clusters from the gas phase and subsequent coarsening - coagulation of these clusters. Molecular dynamics simulations shows qualitative agreement with experimental results.