Experimental analysis of self-similarity and random cascade processes : Application to fully developed turbulence data

Abstract

In the context of fully developed turbulence, Castaing et al. [10] have recently advocated a description of a random cascade process in terms of a kernel G aa , (x) that charac-terizes the nature of the cascade when going from a scale a' to a finer scale a. We elaborate on a method to estimating, directly from experimental data, the shape of G aa , for all scales a and a'. We apply this method to turbulent velocity data and we show that it provides very instructive informations about the soundness of various phenomenological models for the intermittency character of turbulent flows.