Interaction of a synthetic jet with a crossflow boundary layer

An experimental investigation of the interaction between a synthetic jet actuator array and a turbulent boundary layer (Re-theta = 1.79 x 10(3)) is reported. The array consisted of three adjacent, parallel synthetic jet actuators, each with a rectangular orifice having an aspect ratio of 45. The effect of the orientation of the jet orifice, relative to the mean freestream direction, on the jet/boundary-layer interaction was investigated. The steady, spatially stationary features of the flowfield were examined using hot-wire anemometry. Two apparently different flowfields were found in the boundary layer downstream of the actuator array. When the orifice was normal to the mean flow direction, the boundary layer was characterized by a wakelike region in the lee of the jet due to a blockage effect. When the orifice was aligned with the mean flow direction, the How structure was consistent with the presence of longitudinal vortices embedded in the boundary layer.