Superdiffusion of massive particles induced by multi-scale velocity fields

TL;DR

This paper investigates how massive particles exhibit superdiffusive behavior in scale-free velocity fields, revealing that vortex size distribution influences particle dispersion and concentration, similar to fluid systems.

Contribution

It demonstrates the emergence of superdiffusive behavior in particle diffusion due to scale-free vortex distributions, extending understanding of particle dynamics in complex velocity fields.

Findings

Superdiffusive behavior observed in particle mean square separation.

Particle concentration patterns resemble those in fluid turbulence.

Diffusive exponent varies with particle response time.

Abstract

We study drag-induced diffusion of massive particles in scale-free velocity fields, where superdiffusive behavior emerges due to the scale-free size distribution of the vortices of the underlying velocity field. The results show qualitative resemblance to what is observed in fluid systems, namely the diffusive exponent for the mean square separation of pairs of particles and the preferential concentration of the particles, both as a function of the response time.