Aggregation and fragmentation dynamics of inertial particles in chaotic flows

TL;DR

This paper models the complex dynamics of inertial particles in chaotic flows, focusing on how aggregation and fragmentation processes influence particle size distributions and lead to steady states.

Contribution

It introduces a novel model combining aggregation and fragmentation of inertial particles in chaotic flows, revealing steady-state distributions aligned with empirical observations.

Findings

Steady-state particle size distribution depends on fragmentation mechanism.

Model reproduces rain drop size distributions.

Distribution matches experimental stirring tank data.

Abstract

Inertial particles advected in chaotic flows often accumulate in strange attractors. While moving in these fractal sets they usually approach each other and collide. Here we consider inertial particles aggregating upon collision. The new particles formed in this process are larger and follow the equation of motion with a new parameter. These particles can in turn fragment when they reach a certain size or shear forces become sufficiently large. The resulting system consists of a large set of coexisting dynamical systems with a varying number of particles. We find that the combination of aggregation and fragmentation leads to an asymptotic steady state. The asymptotic particle size distribution depends on the mechanism of fragmentation. The size distributions resulting from this model are consistent with those found in rain drop statistics and in stirring tank experiments.