Experiments on the turbulent boundary layer on a flat plate in the wake of another flat plate

Experiments were conducted on the development of the13; turbulent boundary layer on a flat plate which was located in the wake of another flat plate. The investigation covered six cases in which the distance between the plates and the momentum thickness of the upstream wake were varied. The results show that the mean velocity and longitudinal fluctuation in the outer layer can be represented as a slowly varying perturbation of the usual similarity solutions. The perturbation intensity falls by a factor of 2 over a distance of 30 to 90 times the momentum thickness. Though the data show qualitative agreement with several simple correlations and turbulence models, there are13; significant quantitative differences in some cases. The results also suggest feat the large scale motions that have arisen in the wake and the motions generated subsequently in the wall layer are not well correlated