Length scale analysis in wall-bounded turbulent flow by means of dissipation elements

Abstract

The Dissipation Element (DE) method is used to analyse the geometric structure of turbulent pattern for several scalar fields in a turbulent plane channel flow obtained by Direct Numerical Simulations (DNS) of the Navier-Stokes equations. We show that both the probability density function (pdf) and the number of DE exhibit a clear scaling behavior as a function of the wall. Further, a remarkable insensitivity of the pdf is observed with respect to the Reynolds number and the choice of the scalar.