Sudden Collapse of a Granular Cluster

TL;DR

This paper investigates the abrupt collapse of granular clusters in a vibro-fluidized system, providing experimental observations and an analytical flux model that describes the collapse dynamics and subsequent diffusion behavior.

Contribution

It introduces an analytical flux model for cluster collapse in granular gases, highlighting the self-similar and anomalous diffusion aspects post-collapse.

Findings

Clusters become unstable and collapse abruptly at high shaking intensities.

The cluster lifetime is analytically linked to the driving intensity.

Post-collapse, the particle distribution diffuses with an anomalous exponent of 1/3.

Abstract

Single clusters in a vibro-fluidized granular gas in N connected compartments become unstable at strong shaking. They are experimentally shown to collapse very abruptly. The observed cluster lifetime (as a function of the driving intensity) is analytically calculated within a flux model, making use of the self-similarity of the process. After collapse, the cluster diffuses out into the uniform distribution in a self-similar way, with an anomalous diffusion exponent 1/3.