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Inverse velocity statistics in two dimensional turbulence

L. Biferale·M. Cencini·A. Lanotte·D. Vergni
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Abstract

We present a numerical study of two-dimensional turbulent flows in the enstrophy cascade regime, with different large-scale forcings and energy sinks. In particular, we study the statistics of more-than-differentiable velocity fluctuations by means of two recently introduced sets of statistical estimators, namely {\it inverse statistics} and {\it second order differences}. We show that the 2D turbulent velocity field, $\bm u$, cannot be simply characterized by its spectrum behavior, $E(k) \propto k^{-α}$. There exists a whole set of exponents associated to the non-trivial smooth fluctuations of the velocity field at all scales. We also present a numerical investigation of the temporal properties of $\bm u$ measured in different spatial locations.

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L. Biferale, M. Cencini, A. Lanotte, D. Vergni. 2002-04-10. Inverse velocity statistics in two dimensional turbulence. https://doi.org/10.1063/1.1557527

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