Sticky elastic collisions

TL;DR

This paper investigates how purely elastic, sticky collisions influence the dynamics of inertial particles in a 3D flow, revealing significant effects on particle separation and velocity correlations.

Contribution

It introduces a theoretical framework for understanding sticky elastic collisions and demonstrates their impact through numerical simulations, including hydrodynamic interactions.

Findings

Sticky collisions cause particles to remain close for extended periods.

The statistical properties of particle separations are significantly altered.

Hydrodynamic interactions further influence collision dynamics.

Abstract

The effects of purely elastic collisions on the dynamics of heavy inertial particles is investigated in a three-dimensional random incompressible flow. It is shown that the statistical properties of inter-particle separations and relative velocities are strongly influenced by the occurrence of sticky elastic collisions - particle pairs undergo a large number of collisions against each other during a small time interval over which, hence, they remain close to each other. A theoretical framework is provided for describing and quantifying this phenomenon and it is substantiated by numerical simulations. Furthermore, the impact of hydrodynamic interactions is discussed for such a system of colliding particles.