Scaling of second- and higher-order structure functions in turbulent boundary layers

Abstract

The statistical properties of wall turbulence in the logarithmic region are investigated using structure functions of the streamwise velocity. To this end, datasets that span several orders of magnitude of Reynolds numbers are used, up to Re = O(10 ), providing uniquely large scale separations for scrutinising previously proposed scaling laws. For the second-order structure functions strong support is found simultaneously for power-law scalings in the Kolmogorov inertial subrange and for logarithmic scaling at larger scales within the inertial range (z < r 蠐 δ, where z is the distance from the wall, r the scale, and δ the boundary layer thickness). The observed scalings are shown to agree b..