Lagrangian Particle Statistics in Turbulent Flows from a Simple Vortex Model

TL;DR

This paper investigates the statistical behavior of Lagrangian particles in turbulent flows using a simple vortex model composed of Burgers vortices, providing insights into small-scale intermittency through analytical and numerical methods.

Contribution

It introduces a vortex-based model to analyze Lagrangian particle statistics and explores the origins of small-scale intermittency in turbulence.

Findings

Derived velocity increment statistics from vortex assumptions

Identified the origin of small-scale intermittency

Validated results through numerical simulations

Abstract

The statistics of Lagrangian particles in turbulent flows is considered in the framework of a simple vortex model. Here, the turbulent velocity field is represented by a temporal sequence of Burgers vortices of different circulation, strain, and orientation. Based on suitable assumptions about the vortices' statistical properties, the statistics of the velocity increments is derived. In particular, the origin and nature of small-scale intermittency in this model is investigated both numerically and analytically.