Suppression of Rayleigh-Taylor turbulence by time-periodic acceleration

TL;DR

This paper demonstrates that time-periodic acceleration can suppress Rayleigh-Taylor turbulence, leading to a stable, laminar state, with potential applications in controlling turbulent convection.

Contribution

It introduces a novel mechanism of relaminarization of turbulence through alternating acceleration, supported by numerical simulations and theoretical analysis.

Findings

Alternating acceleration suppresses turbulence after initial growth.

The asymptotic mixing layer width depends on the acceleration period.

The system reaches a stationary state with reduced turbulent fluctuations.

Abstract

The dynamics of Rayleigh-Taylor turbulence convection in presence of an alternating, time periodic acceleration is studied by means of extensive direct numerical simulations of the Boussinesq equations. Within this framework, we discover a new mechanism of relaminarization of turbulence: The alternating acceleration, which initially produces a growing turbulent mixing layer, at longer times suppresses turbulent fluctuation and drives the system toward an asymptotic stationary configuration. Dimensional arguments and linear stability theory are used to predict the width of the mixing layer in the asymptotic state as a function of the period of the acceleration. Our results provide an example of simple control and suppression of turbulent convection with potential applications in different fields.