Active flow control studies over an elliptical profile

Erler, Engin
Active flow control by a jet over a 12.5% thick elliptic profile is investigated numerically. Unsteady flowfields are calculated with a Navier Stokes solver. The numerical method is first validated without the jet and with the presence of steady-blowing and pulsating jets. Three jet types, namely steady, pulsating and synthetic jets, are next compared with each other and it is shown that the most drag reduction is achieved by a synthetic jet and the most lift enhancement is achieved by a steady jet. The influences of the jet location, the jet velocity, the jet frequency, the jet slot length and the jet angle on the flowfield is parametrically studied. It is shown that the jet location and the jet velocity are the most effective parameters. The jet parameters are optimized to minimize the drag coefficient while keeping the jet power constant. The drag is reduced by 32.5% for the angle of attack 0 and by 24% for the angle of attack 4.


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Synthetic jet actuators are investigated for rapidly maneuvering airfoils that are regulated by a closed-loop control system. To support active flow-control simulations performed here, the closed-loop system and vehicle dynamics are coupled with computational fluid dynamics. High-frequency sinusoidal pitching simulations with and without synthetic jet actuation indicate that the current synthetic jet actuators provide bidirectional change in aerodynamic forces during rapid maneuvers whose time scales are of...
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Eyi, Sinan; Rogers, SE; Kwak, D (American Institute of Aeronautics and Astronautics (AIAA), 1996-05-01)
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Citation Formats
E. Erler, “Active flow control studies over an elliptical profile,” M.S. - Master of Science, Middle East Technical University, 2008.