Lagrangian acceleration of passive tracers in statistically-steady rotating turbulence

TL;DR

This study investigates how rotation influences the Lagrangian acceleration of passive tracers in steady rotating turbulence, revealing anisotropic effects and changes in acceleration auto-correlations.

Contribution

It provides new experimental insights into the anisotropic statistical properties of Lagrangian acceleration in rotating turbulence using Particle Tracking Velocimetry.

Findings

High-acceleration events are suppressed along the rotation axis.

Horizontal acceleration events are enhanced due to rotation.

Acceleration auto-correlation is strongly amplified perpendicular to rotation and velocity vectors.

Abstract

The statistical properties of the Lagrangian acceleration vector of passive tracers in statistically-steady rotating turbulence is studied by Particle Tracking Velocimetry. Direct effects of the background rotation are the suppression of high-acceleration events parallel to the (vertical) rotation axis, the enhancement of high-acceleration events for the horizontal acceleration, and the strong amplification of the auto-correlation of the acceleration component perpendicular to both the rotation vector \Omega\ and local velocity vector u. The auto-correlation of the acceleration component in the plane set up by \Omega\ and u is only mildly enhanced.