An experimental study was conducted on the performance of synchronized sweeping jets (SJ) for film cooling applications. Various SJ designs were examined, each with a nozzle spacing between 8.5 and 6.0 D_h and an aspect ratio of unity. The synchronized SJ design was compared to an individual SJ as well as a pair of unsynchronized SJ of matching pitch. The frequency response, pressure ratio, spreading angle, and average velocity map were determined in order to characterize each of the designs. Cooling performance of each configuration was evaluated in a wind tunnel at various freestream turbulence levels (Tu = 0.5% and 11.0%) and blowing ratios (M = 1.0, 2.0, 3.0, 4.0). The cooling effectiveness of each design was calculated using wall temperature measurements. Although the synchronized SJ design had similar characteristics to the individual and unsynchronized SJ pair, they were found to have a lower cooling performance at higher blowing ratios. The cause of the decreased cooling effectiveness of the synchronized SJs was attributed to the inner alternating stream wise vortices acting as liftoff vortices for the cooling flow.
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