Abstract
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 conventional hotwire anemometry technique. Ensemble averages of the velocity traces were calculated and velocity profiles through the spots and the surrounding region were plotted. The spots are represented by the ensemble average of the velocity perturbations. The integral boundary layer properties are derived and compared through the spots. The effect of the pressure gradient on the turbulent spots is analysed 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 modelling of the transitional boundary layer.
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Hong, G., Gostelow, J.P. Effect of pressure gradient on turbulent spots. J. of Thermal Science 2, 205–212 (1993). https://doi.org/10.1007/BF02650858
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DOI: https://doi.org/10.1007/BF02650858