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Scaling and universality in turbulent convection

Antonio Celani·Takeshi Matsumoto·Andrea Mazzino·Massimo Vergassola
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Abstract

Anomalous correlation functions of the temperature field in two-dimensional turbulent convection are shown to be universal with respect to the choice of external sources. Moreover, they are equal to the anomalous correlations of the concentration field of a passive tracer advected by the convective flow itself. The statistics of velocity differences is found to be universal, self-similar and close to Gaussian. These results point to the conclusion that temperature intermittency in two-dimensional turbulent convection may be traced back to the existence of statistically preserved structures, as it is in passive scalar turbulence.

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Antonio Celani, Takeshi Matsumoto, Andrea Mazzino, Massimo Vergassola. 2001-10-09. Scaling and universality in turbulent convection. https://doi.org/10.1103/physrevlett.88.054503

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