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A note on dissipation in helical turbulence

P. D. Ditlevsen·P. Giuliani
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Abstract

In helical turbulence a linear cascade of helicity accompanying the energy cascade has been suggested. Since energy and helicity have different dimensionality we suggest the existence of a characteristic inner scale, $ξ=k_H^{-1}$, for helicity dissipation in a regime of hydrodynamic fully developed turbulence and estimate it on dimensional grounds. This scale is always larger than the Kolmogorov scale, $η=k_E^{-1}$, and their ratio $η/ ξ$ vanishes in the high Reynolds number limit, so the flow will always be helicity free in the small scales.

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P. D. Ditlevsen, P. Giuliani. 2001-04-04. A note on dissipation in helical turbulence. https://doi.org/10.1063/1.1404138

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