Interaction of a Synthetic Jet with a Crossflow Boundary Layer

Anexperimentalinvestigationoftheinteractionbetweena syntheticjetactuatorarrayand aturbulentboundary layer (Reµ =1:79 £ 10 3) is reported. The array consisted of three adjacent, parallel synthetic jet actuators, each with a rectangular orie ce having an aspect ratio of 45. The effect of the orientation of the jet orie ce, relative to the mean freestream direction, on thejet/boundary-layerinteraction wasinvestigated. The steady, spatially stationary featuresofthee owe eld wereexaminedusing hot-wireanemometry.Twoapparently differente owe eldswerefound in the boundary layer downstream of the actuator array. When the orie ce was normal to the mean e ow direction, the boundary layer was characterized by a wakelike region in the lee of the jet due to a blockage effect. When the orie ce was aligned with themean e ow direction, the e ow structurewasconsistent with the presenceof longitudinal vortices embedded in the boundary layer.