摘要：

An account is given herein of an investigation conducted to determine the feasibility of artificially thickening a turbulent boundary layer on a flat plate. A description is given of several methods used to thicken artificially the boundary layer. It is shown that it is possible to do substantial thickening and obtain a fully developed turbulent boundary layer, which is free from any distortions introduced by the thickening process, and, as such, is a suitable medium for fundamental research. Measurements of mean velocity, spectrum of u-fluctuation, and intensity of u-fluctuation which served as criterions for determining the state of the layer are presented. Some features of the fully developed turbulent boundary layer with zero pressure gradient are discussed. The mean flow in the boundary layer is compared with the logarithmic laws of mean-velocity distribution derived for pipes and channels, and the existing theories dealing with the shape of the spectrum in isotropic turbulence are applied to the spectrum measured in the outer portion of the boundary layer. It is also shown that the turbulence in the outer portion of the boundary layer has an intermittent character similar to that found for wakes and jets.

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