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arXiv · 0806.3116

Turbulence-condensate interaction in two dimensions

H. Xia·H. Punzmann·G. Falkovich·M. G. Shats
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Abstract

We present experimental results on turbulence generated in thin fluid layers in the presence of a large-scale coherent flow, or a spectral condensate. It is shown that the condensate modifies the third-order velocity moment in a much wider interval of scales than the second one. The modification may include the change of sign of the third moment in the inverse cascade. This observation may help resolve a controversy on the energy flux in mesoscale atmospheric turbulence (10-500 km): to recover a correct energy flux from the third velocity moment one needs first to subtract the coherent flow. We find that the condensate also increases the velocity flatness.

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H. Xia, H. Punzmann, G. Falkovich, M. G. Shats. 2008-11-07. Turbulence-condensate interaction in two dimensions. https://doi.org/10.1103/physrevlett.101.194504

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