Investigation of a three-dimensional turbulent boundary layer with separation in incompressible flow

Development of a turbulent boundary layer was studied on the floor of an asymmetric diffuser producing lateral pressure gradients, and longitudinal pressure gradients large enough to cause separation. Maximum flow velocity was 29 m per sec with momentum thickness Reynolds number of 20,000 at separation. Pressure distributions, velocity profiles, viscous layer parameters and flow deflections are discussed. A separation front is defined and the flow beyond it is described. The separation occurs further downstream than it does for a two dimensional case with similar streamwise gradients. The results were examined in relation to Colesa Wake hypothesis and a degree of distortion found to be present.