Energy Loss at Propagating Jamming Fronts in Granular Gas Clusters

TL;DR

This study investigates how energy dissipates during the impact of dense granular clusters composed of solid CO₂ particles, revealing a power-law decay in kinetic energy due to propagating jamming fronts.

Contribution

It introduces a new understanding of energy loss mechanisms in granular gases during impact, supported by experiments and simulations showing a specific power-law behavior.

Findings

Kinetic energy decreases by over 90% upon impact.

Energy loss follows a power law, ΔE = -Kt^{3/2}.

Experimental and simulation results agree on the energy dissipation pattern.

Abstract

We explore the initial moments of impact between two dense granular clusters in a two-dimensional geometry. The particles are composed of solid CO$_{2}$ and are levitated on a hot surface. Upon collision, the propagation of a dynamic "jamming front" produces a distinct regime for energy dissipation in a granular gas in which the translational kinetic energy decreases by over 90%. Experiments and associated simulations show that the initial loss of kinetic energy obeys a power law in time, $\Delta E=-Kt^{3/2}$, a form that can be predicted from kinetic arguments.