Universal statistics of nonlinear energy transfer in turbulent models

A class of shell models for turbulent energy transfer at varying the intershell separation, lambda, is investigated. Although in the continuum limit (lambda --> 1) the model becomes nonintermittent, we found universal aspects of the velocity statistics which can be interpreted in the framework of log-Poisson distributions, as proposed by She and Waymire [Phys. Rev. Lett. 74, 262 (1995)]. Universal properties of the free parameters entering log-Poisson description and connections with similar results reported in other shell models investigations and in real turbulent flows are discussed.