Symmetry Breaking, Anomalous Scaling and Large-Scale Flow Generation in a Convection Cell

1999/09/15 by Ananias G. Tomboulides, Tomboulides, Ananias G., Victor Yakhot +1
Physics and Astronomy · #Chaotic Dynamics (nlin.CD) #FOS: Physical sciences #chao-dyn #nlin.CD

paper · pdf · doi:10.48550/arxiv.chao-dyn/9909025

27 pages, 19 figures

arxiv created 1999/09/15 · arxiv updated 2009/11/30

Abstract

We consider a convection process in a thin loop. At Ra=Ra^′_cr a first transition leading to the generation of corner vortices is observed. At higher Ra a coherent large-scale flow, which persists for a very long time, sets up. The mean velocity v, mass flux \dm, and the Nusselt number Nu in this flow scale with Ra as v ∝ m ∝ Ra^0.45 and Nu∝ Ra^0.9, respectively. The time evolution of the coherent flow is well described by the Landau amplitude equation within a wide range of Ra-variation. The anomalous scaling of the mean velocity, found in this work, resembles the one experimentally observed in the ``hard turbulence'' regime of Benard convection. A possible relation between the two systems is discussed.

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