Experimental Study of Delay of Separation on a NACA 0015 Wing Model Using Synthetic Jet Actuators

Abstract

An experimental study has been conducted in the Cal Poly ME 0.61 m x 0.61 m (2 ft x 2 ft) subsonic wind tunnel of the effect of a piezoelectric synthetic jet actuator at 10% chord on a NACA 0015 finite wing up to α = 20° at Re C = 100,000. It was observed that the actuation is able to delay the separation over the NACA 0015 finite wing model up to α = 20°. For all the Cμ values tested, the synthetic jet excitation is effective at F + = 1, 2.8, and 13.9 at α = 16°, but only at F+ = 13.9 at α = 20°. At α = 16°, the C p suction peak under the synthetic jet excitation at F + = 1, 2.8, and 13.9 all gradually reduce from C p ≅ -4 at in the inboard area to about Cp ≅ -3 near the wingtip, about 25% reduction. The situation is similar for F + = 13.9 at α = 20° except at 2y/b = 0.30, the most inboard testing position, where the excitation shows almost no effect. The surprising result is that slit is not the only actuation influencing the flow. For F + from 1 to 2.8, the synthetic jet is indeed the most effective configuration and is successful in causing flow attachment as seen in previous experiments. For F + = 13.9, however, the flow is successfully attached with the model vibration caused by the actuators alone without the slit at 16°. At 20°, this configuration was not successful in delaying separation.v