Control of vortex shedding on two- and three-dimensional airfoils
نویسندگان
چکیده
We review and expand on the control of separated flows over flat plates and airfoils at low Reynolds numbers associated with micro air vehicles. Experimental observations of the steady-state and transient lift response to actuation, and its dependence on the actuator, airfoil geometry, and flow conditions are discussed and an attempt is made to unify them in terms of their excitation of periodic and transient vortex shedding. We also examine strategies for closed-loop flow and flight control utilizing actuation of leading-edge vortices.
منابع مشابه
Effects Of Frequency Variation At Inlet Flow On The Vortex Shedding Frequency Behind A Circular Cylinder
In many applications the flow that past bluff bodies has frequency nature (oscillated) and it is not uniform. This kind of flow has effects on the formation of vortex shedding behind bluff bodies. In this paper the flow around a circular cylinder was numerically simulated. The effects of frequency variation at inlet flow on the vortex shedding frequency were investigated. The transient Two-Dime...
متن کاملVortex shedding in a two-dimensional diffuser: theory and simulation of separation control by periodic mass injection
We develop a reduced-order model for large-scale unsteadiness (vortex shedding) in a two-dimensional diffuser and use the model to show how periodic mass injection near the separation point reduces stagnation pressure loss. The model estimates the characteristic frequency of vortex shedding and stagnation pressure loss by accounting for the accumulated circulation due to the vorticity flux into...
متن کاملEffect of Camber and Thickness on the Aerodynamic Properties of an Airfoil in Ground Proximity (RESEARCH NOTE)
A linear vortex panel method is extended to include the effect Abstract of ground proximity on the aerodynamic properties of two dimensional airfoils. The image method is used to model the ground effect . According to the results, lift coefficient of an airfoil may increase or decrease in ground effect based on a combinative effect of its camber, thickness, angle of attack and ground clearance....
متن کاملStall Vortex Shedding over a Compressor Cascade (RESEARCH NOTE)
The unstable flow with rotating-stall-like (RS) effects in a rotor-cascade of an axial compressor was numerically investigated. The RS was captured with the reduction in mass flow rate and increasing of exit static pressure with respect to design operating condition of the single rotor. The oscillatory velocity traces during the stall propagation showed that the RS vortices repeat periodically,...
متن کاملStall Vortex Shedding Over a Compressor Cascade (RESEARCH NOTE)
The unstable flow with rotating-stall-like (RS) effects in a rotor-cascade of an axialcompressor was numerically investigated. The RS was captured with the reduction in mass flow rateand increasing of exit static pressure with respect to design operating condition of the single rotor.The oscillatory velocity traces during the stall propagation showed that the RS vortices repeatperiodically, and...
متن کامل