Relative velocities in bi-disperse turbulent aerosols: simulations and theory

TL;DR

This paper combines direct numerical simulations and theoretical analysis to study the relative velocities of bi-disperse particles in turbulent aerosols, validating recent theoretical predictions with simulation data.

Contribution

It provides a detailed comparison between simulations and theory for the distribution and moments of relative velocities in bi-disperse turbulent aerosols, confirming theoretical models.

Findings

Good agreement between simulations and theoretical predictions

Distribution of relative velocities matches theoretical shape

Moments of relative velocities align with theoretical expectations

Abstract

We perform direct numerical simulations of a bi-disperse suspension of heavy spherical particles in forced, homogeneous, and isotropic three-dimensional turbulence. We compute the joint distribution of relative particle distances and longitudinal relative velocities between particles of different sizes, and compare the results with recent theoretical predictions [Meibohm et al. Phys. Rev. E 96 (2017) 061102] for the shape of this distribution. We also compute the moments of relative velocities as a function of particle separation, and compare with the theoretical predictions. We observe good agreement.