Intermittency in Stochastically Perturbed Turbulent Models
نویسنده
چکیده
Random dynamical models obtained as a perturbation of the GOY (GledzerOhkitani-Yamada) shell model for three-dimensional turbulence are defined. Both static (time-independent) and dynamical scaling properties of the randomly perturbed model are studied. The random static-inviscid manifold, in contrast to the dynamical evolution, does not show intermittent scaling laws. This behavior is linked to the absence of large deviation in the random-map connecting fluctuations of velocities at different scales. The importance of inviscid conserved quantities on the intermittent statistics is discussed. Different random dynamical perturbations such that only energy is conserved in the inviscid and unforced limit are investigated, lntermittency is weakly affected by random perturbations.
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