Explosive growth of inhomogeneities in the distribution of droplets in a turbulent air

TL;DR

This paper investigates how inhomogeneities in droplet distribution grow explosively in turbulent air, highlighting the role of caustics and flow dynamics in accelerating clustering and particle separation.

Contribution

It introduces a model describing the explosive formation of caustics and their impact on droplet clustering in turbulent flows, revealing exponential growth mechanisms.

Findings

Caustics cause rapid clustering of particles.

Exponential growth of particle separation observed.

Flow smoothness influences clustering dynamics.

Abstract

We study how the spatial distribution of inertial particles evolves with time in a random flow. We describe an explosive appearance of caustics and show how they influence an exponential growth of clusters due to smooth parts of the flow, leading in particular to an exponential growth of the average distance between particles.