Multiple equilibria in fingering double diffusive convection turbulence

TL;DR

This paper explores the complex behavior of fingering double diffusive convection turbulence, revealing multiple equilibrium states, abrupt transitions, and distinct transport properties within staircases, advancing understanding of convection phenomena.

Contribution

It uncovers multiple equilibria, hysteresis, and differing transport behaviors in fingering double diffusive convection, challenging existing models and providing new insights.

Findings

Multiple equilibria exist for the same control parameters.

Transitions between single and multi-layer structures can be abrupt and hysteretic.

Finger interfaces within staircases exhibit different transport behaviors and obey Stern number constraints.

Abstract

We report here some intriguing properties of fingering double diffusive convection turbulence, i.e. convection flow driven simultaneously by an unstable salinity gradient and a stable temperature gradient. Multiple equilibria can be established in such flow for the same control parameters, either by setting different initial scalar distribution or different evolution history. Transition between a single finger layer and multi-layer staircase can be abrupt and hysteresis. Unlike a deep finger layer, a model widely used in literature, finger interfaces within staircases show totally different transport behaviors and seem to obey the Stern number constrain. All these findings provide important new insights to fingering double diffusive convection, and to general convection turbulence.