Lift Enhancement for Low-Aspect-Ratio Wings with Periodic Excitation
نویسندگان
چکیده
In an effort to enhance lift on low-aspect-ratio rectangular flat-plate wings in low-Reynolds-number poststall flows, periodic injection of momentum is considered along the trailing edge in this numerical study. The purpose of actuation is not to reattach the flowbut to change the dynamics of thewake vortices such that the resulting lift force is increased. Periodic forcing is observed to be effective in increasing lift for various aspect ratios and angles of attack, achieving a similar lift enhancement attained by steady forcingwith lessmomentum input. Through the investigation on the influence of the actuation frequency, it is also found that there exists a frequency at which the flow locks on to a time-periodic high-lift state.
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