Characteristics of asymmetric turbulent near wakes

Abstract

The mean-velicity and turbulence quantities in a few qualitatively different types of asymmetric two-dimensional turbulent near wakes in nearly zero-pressure gradient have been experimentally studied. In all cases, the log-law similarity of the boundary layers was found to continue into the initial part of the wake same similarity variables as in the boundary layers on the same side, provided the origin of the normal distance is taken at the smooth extension of the respective surfaces. The Reynolds stress profiles show sharp peaks just downstream of the trailing, edge, and the magnitudes of the peaks are found to be related to the values of the surface friction at the trailing edge. These peaks grow into the full width of the wake to form the far wake profiles. In this process, the turbulent diffusions of the Reynolds stresses are very important and when the size- asymmetry is severe, is not clearly of gradient-transport type.