Heavy Particle Clustering in Inertial Subrange of High--Reynolds Number Turbulence

TL;DR

This paper uses direct numerical simulation to analyze how inertial particles cluster in the inertial subrange of high-Reynolds-number turbulence, revealing new clustering behaviors beyond the near dissipation range.

Contribution

It demonstrates the presence of particle clustering in the inertial subrange and models the number density spectrum using a rational function of the scale-dependent Stokes number.

Findings

Clustering occurs in the inertial subrange at high Reynolds numbers.

Number density spectrum exhibits a characteristic bump.

Clustering is linked to modulation of preferential concentration.

Abstract

Direct numerical simulation of homogeneous isotropic turbulence shows pronounced clustering of inertial particles in the inertial subrange at high Reynolds number, in addition to the clustering typically observed in the near dissipation range. The clustering in the inertial subrange is characterized by the bump in the particle number density spectra and is due to modulation of preferential concentration. The number density spectrum can be modeled by a rational function of the scale-dependent Stokes number.