The Large scale instability in rotating fluid with small scale force

TL;DR

This paper investigates a newly discovered large-scale instability in rotating turbulent flows driven by small-scale forcing, using multi-scale asymptotic methods to analyze nonlinear dynamics and vortex formation.

Contribution

It introduces a novel large-scale instability mechanism in rotating turbulence caused by small-scale forcing, with a detailed nonlinear analysis of vortex kink generation.

Findings

Identification of a new large-scale instability in rotating turbulence

Derivation of nonlinear equations describing the instability

Observation of vortex kink formation during nonlinear stage

Abstract

In this paper, we find a new large scale instability displayed by a rotating flow in forced turbulence. The turbulence is generated by a small scale external force at low Reynolds number. The theory is built on the rigorous asymptotic method of multi-scale development. The nonlinear equations for the instability are obtained at the third order of the perturbation theory. In this article, we explain a detailed study of the nonlinear stage of the instability and generation vortex kinks.