AN EXPERIMENTAL SIMULATION OF HIGH LIFT WAKE FLOWS AT HIGH REYNOLDS NUMBER

To address the need for building-block flow physics studies involving high lift aerodynamics, experiments have been carried out to investigate the behavior of the wake region of a multielement airfoil. This experiment employed a configuration of two aerodynamic elements, arranged to be representative of a high lift system with a singleslotted flap. A 24-foot long flat plate represented the main element, and was used to generate the wake which convected into the flowfield around the 5-foot chord flap element. The Reynolds number of the wake based on the length of the flat plate and freestream velocity was 10.2 million. The flat plate wake was investigated using hot wire anemometry techniques, and mean and fluctuating velocities were measured with an xwire probe. Measurements were made across the wake at 7 streamwise stations, for two Reynolds number conditions and two flap configurations. The effects of curvature and pressure gradient on the mean and fluctuating velocities were examined. Wake integral properties were also calculated. Results of the experiment were compared to existing experimental datasets as well as computational results from a commonlyused multielement flow solver.

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