Effect of weak rotation on large-scale circulation cessations in turbulent convection

Michael Assaf, Luiza Angheluta, Nigel Goldenfeld

Published 2012-05-16, updated 2012-08-19Version 2

We investigate the effect of weak rotation on the large-scale circulation (LSC) of turbulent Rayleigh-B\'{e}nard 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 probability distribution function 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.