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Orientation changes of the large-scale circulation in turbulent Rayleigh-Benard convection

Eric Brown·Alexei Nikoleanko·Guenter Ahlers
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Abstract

We present measurements of the orientation theta_0(t) of the large-scale circulation (LSC) of turbulent Rayleigh-Benard convection in cylindrical cells of aspect ratio 1. theta_0(t) undergoes irregular reorientations. It contains reorientation events by rotation through angles Delta theta with a monotonically decreasing probability distribution p(Delta theta), and by cessations (where the LSC stops temporarily) with a uniform p(Delta theta). Reorientations have Poissonian statistics in time. The amplitude of the LSC and the magnitude of the azimuthal rotation rate have a negative correlation.

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Eric Brown, Alexei Nikoleanko, Guenter Ahlers. 2005-06-03. Orientation changes of the large-scale circulation in turbulent Rayleigh-Benard convection. https://doi.org/10.1103/physrevlett.95.084503

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