Gravity-driven clustering of inertial particles in turbulence

TL;DR

This paper reports a novel gravity-induced clustering phenomenon in turbulent flows, where heavy particles form vertical strip patterns due to flow velocity gradient skewness, revealed through simulations.

Contribution

It introduces a new type of particle clustering driven solely by gravity, with a detailed explanation based on flow velocity gradient skewness.

Findings

Gravity causes heavy particles to cluster in vertical strips.

Flow velocity gradient skewness leads to horizontal particle convergence.

Simulation results confirm the gravity-driven clustering mechanism.

Abstract

We report a new kind of particle clustering caused purely by gravity, discovered in our simulation of particle-laden turbulence. Clustering in a vertical strip pattern forms when strong gravity acts on heavy particles. This phenomenon is explained by the skewness of the flow velocity gradient in the gravitational direction experienced by particles, which causes horizontal convergence of particles.