title: Cascades in helical turbulence.
abstract: We suggest the existence of a characteristic inner scale xi 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 eta and their ratio eta/xi vanishes in the high Reynolds number limit, so the flow will always be helicity free in the small scales. These ideas are illustrated in a shell model of turbulence.
authors: The Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen O, Denmark.
authors: P D
authors: PD
authors: Ditlevsen
authors: P
authors: P
authors: Giuliani