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Turbulent spots were generated artificially to simulate natural spots in the transitional boundary layer.The spots at the final stage under zero and adverse pressure gradients were measured using conventionalhotwire anemometry technique. Ensemble averages of the velocity traces were calculated and velocityprofiles through the spots and the surrounding region were plotted. The spots are represented by theensemble average of the velocity perturbations. The integral boundary layer properties are derived andcompared through the spots. The effect of the pressure gradient on the turbulent spots is analysedwith the structure of the spots and the ’calmed region’ following the spots.The information acquired from spot measurement should improve the understanding of the physicalproperties of the turbulence spots and therefore the modelling of the transitional boundary layer.
Turbulent spots were generated artificially to simulate natural spots in the transitional boundary layer. The spots at the final stage under zero and adverse pressure gradients were measured using conventionalhotwire anemometry technique. Ensemble averages of the velocity traces were calculated and velocityprofiles through the spots and the surrounding. The spots are plotted the theensemble average of the velocity perturbations. The integral boundary layer properties are derived andcompared through the spots. The effect of the pressure gradient on the turbulent spots is analyzed with the structure of the spots and the ’calmed region ’following the spots. The information acquired from spot measurement should improve the understanding of the physical properties of the turbulence spots and therefore the modeling of the transitional boundary layer.