Most singular vortex structures in fully developed turbulence

TL;DR

This paper investigates the most dissipative vortex structures in high Reynolds number turbulence, confirming their scaling behavior and co-dimension, and comparing statistical models for their distribution.

Contribution

It provides experimental evidence for the scaling of intense vortex structures and compares log-Poisson and log-binomial models for their statistics.

Findings

Most intense structures have co-dimension less than 2

Experimental data support log-Poisson scaling

Comparison between log-Poisson and log-binomial models

Abstract

Using high Reynolds number experimental data, we search for most dissipative, most intense structures. These structures possess a scaling predicted by log-Poisson model for the dissipation field $\epsilon_r$. The probability distribution function for the exponents $\alpha$, $\epsilon_r\sim e^{\alpha a}$, has been constructed, and compared with Poisson distribution. These new experimental data suggest that the most intense structures have co-dimension less than 2. The log-Poisson statistics is compared with log-binomial which follows from the random $\beta$-model.