Effect of Weak Rotation on Large-Scale Circulation Cessations in Turbulent Convection

Michael Assaf, Luiza Angheluta, and Nigel Goldenfeld

Phys. Rev. Lett. 109, 074502 – Published 16 August 2012

Abstract

We investigate the effect of weak rotation on the large-scale circulation (LSC) of turbulent Rayleigh-Bénard convection, using the theory for cessations in a low-dimensional stochastic model of the flow previously studied. We determine the cessation frequency of the LSC as a function of rotation, and calculate the statistics of the amplitude and azimuthal velocity fluctuations of the LSC as a function of the rotation rate for different Rayleigh numbers. Furthermore, we show that the tails of the reorientation PDF remain unchanged for rotating systems, while the distribution of the LSC amplitude and correspondingly the cessation frequency are strongly affected by rotation. Our results are in close agreement with experimental observations.

Received 13 May 2012

DOI:https://doi.org/10.1103/PhysRevLett.109.074502

Authors & Affiliations

Michael Assaf¹, Luiza Angheluta^1,2, and Nigel Goldenfeld¹

¹Department of Physics, University of Illinois at Urbana-Champaign, Loomis Laboratory of Physics, 1110 West Green Street, Urbana, Illinois 61801-3080, USA
²Physics of Geological Processes, Department of Physics, University of Oslo, Norway