Stability of Taylor-Couette Flow with Odd Viscosity

TL;DR

This paper explores how odd viscosity influences the stability and vortex patterns of Taylor-Couette flow, revealing that large odd viscosity can suppress flow instabilities and alter vortex structures.

Contribution

It provides the first analytical and numerical analysis of odd viscosity effects on Taylor-Couette flow stability, including critical Taylor number derivations and vortex pattern modifications.

Findings

Odd viscosity creates secondary vortices in Taylor-Couette flow.

Large odd viscosity suppresses flow instability regardless of sign.

Odd viscosity significantly alters vortex patterns and stability diagrams.

Abstract

Odd viscosity can emerge in 3D hydrodynamics when the time reversal symmetry is broken and anisotropy is introduced. Its ramifications on the stability of the prototypical Taylor-Couette flow in curved geometries have remained unexplored. Here, we investigate the effects of odd viscosity on the stability of Taylor-Couette flow under axisymmetric perturbations both analytically and numerically, deriving analytically the critical Taylor number for different odd viscosities in the narrow gap case as well as fully numerically implementing the wide gap case. We find that the odd viscosity modifies the vortex pattern by creating secondary vortices, and exerts an intriguing ``lever'' effect in the stability diagram, completely suppressing the instability of Taylor-Couette flow under axisymmetric perturbations when the odd viscosity is large, irrespective of its sign. Our findings highlight the role of odd viscosity for the rich flow patterns of the Taylor-Couette geometry and provide guidance for viscometer experiments when odd viscosity is present.