Turbulence Measurements of a Two-Dimensional NACA 0036 Airfoil with Synthetic Jet Flow Control

An active ∞ow control experiment was conducted on a 2-ft chord NACA 0036 airfoil in a 3-ft by 4-ft Wind Tunnel at Re = 1:0 £ 10 6 . The model was equipped with oscillatory jet actuators at x/c = 0.30 and 0.65 that provided 120 Hz periodic excitation at a C„ = 0:86% through 0.06-in wide slots. Three difierent slot conflgurations were tested, including a baseline with no slots. Surface pressure data was collected to compare to previous tests and to combine with turbulence data to aid future CFD modeling efiorts. Turbulence data, measured by hotwire anemometry, was compared with and without ∞ow control. Pressure data corroborates previous test data and provides more points for CFD validation. Hotwire results showed ∞ow control reduced the separated wake size and brought the high Reynolds shear stress layer closer to the airfoil surface. The position of this layer to the surface was altered more signiflcantly than the magnitude of the peak shear stresses. Flow control was shown to increase turbulent energy in the attached boundary layer downstream of the slot but to have little efiect upstream. These results provide further justiflcation to continue assessing the potential of active ∞ow control to reduce separation drag of rotorcraft airframe components.