Experimental study on the evolution of a wall layer from a wake

Abstract

Experiments are conducted on the development of the turbulent boundary layer on a flat plate located in the wake of another flat plate. The mean velocity field and the Reynolds stresses of the evolving layer are measured in six cases involving different wake conditions. The study is on the evolution of the wall layer developing under zero pressure gradient. The results indicate significant influence of the wake on the evolving layer. The perturbed wall layer has a low shape factor accompanied by lower Reynolds shear stress. The perturbation intensity falls by a factor of 2 over a distance of 50-100 momentum thicknesses. The data analysis reveal multilayered structure and growth of an internal layer. The applicability of some simple correlations and turbulence models for these complex flows are also examined.