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arXiv · 0805.2182

On the decrease of intermittency in decaying rotating turbulence

J. Seiwert·C. Morize·F. Moisy
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Abstract

The scaling of the longitudinal velocity structure functions, $S_q(r) = < | δu (r) |^q > \sim r^{ζ_q}$, is analyzed up to order $q=8$ in a decaying rotating turbulence experiment from a large Particle Image Velocimetry (PIV) dataset. The exponent of the second-order structure function, $ζ_2$, increases throughout the self-similar decay regime, up to the Ekman time scale. The normalized higher-order exponents, $ζ_q / ζ_2$, are close to those of the intermittent non-rotating case at small times, but show a marked departure at larger times, on a time scale $Ω^{-1}$ ($Ω$ is the rotation rate), although a strictly non-intermittent linear law $ζ_q / ζ_2 = q/2$ is not reached.

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J. Seiwert, C. Morize, F. Moisy. 2008-05-15. On the decrease of intermittency in decaying rotating turbulence. https://doi.org/10.1063/1.2949313

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