Patent
Airfoil with dynamic stall control by oscillatory forcing
TLDR
In this article, a method for inhibiting dynamic stall of an airfoil by causing a fluid to flow out of at least one location on the air-foil was proposed.Abstract:
A method for inhibiting dynamic stall of an airfoil by causing a fluid to flow out of at least one location on the airfoil. This location may be anywhere on the airfoil; but if the location is within one-quarter of the airfoil chord from the leading edge and the fluid flow has non-zero net mass flux, then the fluid flow is modulated at a frequency described by a Strouhal ratio greater than one.read more
Citations
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Journal ArticleDOI
The control of flow separation by periodic excitation
TL;DR: In this article, a review of the control of flow separation from solid surfaces by periodic excitation is presented, with an emphasis on experimentation relating to hydrodynamic excitation, although acoustic methods as well as traditional boundary layer control, such as steady blowing and suction are discussed in order to provide an appropriate historical context for recent developments.
Patent
Active drag and thrust modulation system and method
TL;DR: In this paper, the authors used energy beams to generate virtual extensions of a vehicle to enhance traveling efficiency, such as roughening or widening the sails of a sailing ship or modifying the keel or hull of a ship to improve its hydrodynamic characteristics.
Patent
Vibration-driven acoustic jet controlling boundary layer separation
TL;DR: In this article, a single and double chambers drive nozzles separated streamwise or spanwise on airfoils (blades, wings, and fuselages) and provide a net time averaged flow of fluid particles of increasing momentum flux into the boundary layer to defer or prevent the onset of boundary layer separation.
Patent
Blade for a rotor of a wind energy turbine
TL;DR: In this paper, the authors describe a rotor blade for a wind energy turbine that includes opposite upper and lower faces, opposite leading and trailing edges connecting the upper face and the lower face, and at least one air outlet opening arranged on the leading and the trailing edge for discharging pressurized air into the air around the upper faces.
PatentDOI
Tangentially directed acoustic jet controlling boundary layers
TL;DR: In this paper, the authors describe an acoustic jet that directs high momentum flux gas particles essentially tangentially into the boundary layer of the flow in a diffuser, an engine air inlet, a jet engine gas flow path or on the suction surface of an airfoil.
References
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Journal ArticleDOI
Delay of Airfoil Stall by Periodic Excitation
TL;DR: In this article, it was demonstrated that oscillatory blowing can delay separation from a symmetrical airfoil much more effectively than the steady blowing used traditionally for this purpose than the traditional slow blowing.
Journal ArticleDOI
Oscillatory Blowing: A Tool to Delay Boundary-Layer Separation
TL;DR: In this article, the effects of oscillatory blowing as a means of delaying separation are discussed, and experiments were carried out on a follow, flapped NACA 01115 airfoil equipped with a two-dimensional slot over the hinge of the flap.
PatentDOI
Control of laminar flow in fluids by means of acoustic energy
TL;DR: In this paper, the authors proposed to reduce the point of transition from laminar flow to turbulent flow in aerodynamic boundary layers on the surfaces of aircraft by radiating acoustic energy at frequencies greater than twice the critical TollmeinSchlichting frequency into the boundary layer.
Patent
Method and apparatus for delaying the separation of flow from a solid surface
TL;DR: In this paper, an active perturbation-producing element on the solid surface is driven to induce oscillations in the boundary layer of the fluid stream about an axis substantially perpendicular to the solid surfaces, to enhance the mixing of boundary layer in fluid stream.
Journal ArticleDOI
Dynamic Stall Control for Advanced Rotorcraft Application
TL;DR: In this article, a leading-edge slat, a deformable leading edge, and upper surface blowing are proposed to improve the lift, drag, and pitching moment characteristics of rotor blades.