Vortex Tubes in Turbulence Velocity Fields at High Reynolds Numbers

TL;DR

This study investigates vortex tubes in turbulent flows at high Reynolds numbers, revealing universal scaling laws for their size and circulation velocity across different flow configurations.

Contribution

It provides new insights into the scaling behavior of vortex tubes, including their radius and circulation velocity, across various turbulence production setups.

Findings

Vortex tube radius scales with Kolmogorov length.

Circulation velocity scales with Kolmogorov velocity.

Scaling laws are consistent across different flow configurations.

Abstract

The elementary structures of turbulence, i.e., vortex tubes, are studied using velocity data obtained in laboratory experiments for boundary layers and duct flows at microscale Reynolds numbers 332-1934. While past experimental studies focused on intense vortex tubes, the present study focuses on all vortex tubes with various intensities. We obtain the mean velocity profile. The radius scales with the Kolmogorov length. The circulation velocity scales with the Kolmogorov velocity, in contrast to the case of intense vortex tubes alone where the circulation velocity scales with the rms velocity fluctuation. Since these scaling laws are independent of the configuration for turbulence production, they appear to be universal at high Reynolds numbers.