This thesis studies the effect of turbulent boundary layer thickness on the wake dynamics of a blunt trailing edge profiled body, and investigates a flow control technique by applying passive vortex generators with different size and spacing. The boundary layer thickness was varied by changing the model chord to thickness ratio from 30 to 150 and by changing the Reynolds number from 10,000 to 35,000. Consequently, the displacement thickness in this study ranges from 0.077d to 0.319d, which results in a decrease of Strouhal number from 0.202 to 0.168, and increase in formation length from 0.863d to 1.048d, and an increase in the average wavelength of secondary instability from 2.12 d to 3.33d. The effectiveness of the passive flow control was found to have little dependence on Reynolds number, and the most back pressure recovery of 30% and formation length elongation of 80% were achieved with the smallest passive vortex generators spaced at 2.4 d, which is close to the wavelength of the secondary instability.
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