Abstract: A stall trigger system is disclosed having an aircraft wing tip or aircraft wing tip device, a plurality of sets of stall triggers distributed along a span of the aircraft wing tip or aircraft wing tip device. Each set of stall triggers comprises one or more stall triggers which can be activated to trigger local separation of air flow over the aircraft wing tip or aircraft wing tip device, and each set of stall triggers has a different activation threshold. A control system configured to monitor a parameter, and activate each set of stall triggers in response to the parameter reaching its respective activation threshold.

Abstract: A rotor blade for a wind turbine is provided. The rotor blade includes an aerodynamic device for influencing the airflow flowing from the leading-edge section of the rotor blade to the trailing edge section of the rotor blade. The aerodynamic device is mounted at a surface of the rotor blade and includes a pneumatic or hydraulic actuator, such as a hose a cavity, of which the volume depends on the pressure of a fluid being present inside the pneumatic or hydraulic actuator. The rotor blade further includes a control unit for controlling the pressure of the fluid in the hose or the cavity of the aerodynamic device.

Abstract: Automated deployable fences for aircraft wings are described. An example apparatus includes a fence, a latching actuator, and a biasing actuator. The fence is coupled to a wing of an aircraft. The fence is movable relative to the wing between a stowed position in which a panel of the fence extends along a skin of the wing, and a deployed position in which the panel extends at an upward angle away from the skin. The panel impedes a spanwise airflow along the wing when the fence is in the deployed position. The latching actuator is movable between a first position in which the latching actuator maintains the fence in the stowed position, and a second position in which the latching actuator releases the fence from the stowed position. The latching actuator moves from the first position to the second position in response to a control signal received at the latching actuator.

Abstract: An aircraft designing apparatus receives set values of design parameters related to the shape of an intake duct, creates analysis models for an aerodynamic characteristic analysis and a radar-cross-section analysis by using the values of the design parameters, calculates aerodynamic characteristics and radar-cross-section characteristics of the intake duct, and determines whether or not this analytical result satisfies a preset design condition. If it is determined that the analytical result does not satisfy the design condition, the values of the design parameters are updated. The updating of the design parameters, the analyses of the aerodynamic characteristics and the radar-cross-section characteristics, and the determining process are repeated until it is determined that the analytical result satisfies the design condition.

Abstract: A vortex generator for a wind turbine blade to be mounted to a wind turbine blade includes: a platform portion to be mounted to a surface of the wind turbine blade; and at least one fin disposed upright on the platform portion. The platform portion has a cross section having a curved convex shape, at least along a blade spanwise direction of the wind turbine blade.

Abstract: Drag reduction systems and methods for an aircraft include a first vortex generator position on a portion of the aircraft, and a second vortex generator positioned on the portion of the aircraft. The first vortex generator is associated with the second vortex generator. The first vortex generator is asymmetrical to the second vortex generator in relation to a coupling axis in order to offset the longitudinal contribution of the vortex generator to vehicle cross-sectional area.

Abstract: Methods of forming a cooling passage on a turbine component having a component wall with an internal surface and an external surface, are disclosed. An opening is formed passing through the component wall and fluidly connecting the internal and external surfaces. The opening includes a metering section extending from the internal surface to a metering end, and a diffuser area extending from the metering end to the external surface. A preformed cap element is added to close a portion of the diffuser area to form the cooling passage with a diffusion section extending from the metering end to the external surface. The preformed metal cap element includes a projection extending internally of the external surface and into the diffusion area to define an internally facing section of the diffusion section. The cooling passage extends through the component wall and fluidly connects the internal surface and the external surface.

Abstract: Embodiments of the subject invention relate to an air vehicle and a power source. Embodiments can operate at reasonable power levels for hovering and withstanding expected wind gusts. Embodiments can have a diameter less than 15 cm. Embodiments can have one or more smooth (continuous curvature) surface and can be operated using electromagnetic and electrohydrodynamic principles. The wingless design of specific embodiments can allow operation with no rotating or moving components. Additional embodiments can allow active response to the surrounding flow conditions. The issue of low lift to drag ratio and degradation of airfoil efficiency due to the inability of laminar boundary layers attachment can also be significantly reduced, or eliminated. The electromagnetic force can be generated by applying a pulsed (alternating/rf) voltage between a set of grounded and powered electrodes separated by a polymer insulator, dielectric, or other material with insulating properties.

Abstract: A fluidic system is disclosed. The system comprises a plurality of fluidic oscillatory actuators, and at least one synchronization conduit connecting two or more of the actuators such as to effect synchronization between oscillations in the two or more connected actuators.

Abstract: An aerodynamic body with an aerodynamic body surface that creates a contoured surface for a fluid to stream around, with a device to influence the flow of the fluid streaming around the aerodynamic surface. The flow-influencing device includes a passage to link the fluid streaming around the aerodynamic surface with an actuator space of an aspirating and purging device situated in the aerodynamic body, and an indentation that is situated next to the passage, which is formed by a recessed section of the aerodynamic surface on a flow-influencing region within the contoured surface of the aerodynamic surface, so that a boundary wall is configured as part of the recessed surface lying opposite the indentation. The aspirating and purging device can generate a swirl in the flow of the fluid streaming around the aerodynamic surface, the rotational axis of which is directed along the assumed aerodynamic body chord direction.

Abstract: Systems and methods for controlling air vehicle boundary layer airflow are disclosed. Representative methods can include applying electrical energy bursts and/or other energy bursts in nanosecond pulses in the boundary layer along a surface of an air vehicle. In a particular embodiment, electrical energy is discharged into the boundary layer to reduce the tendency for the boundary layer to separate and/or to reduce the tendency for the boundary layer to transition from laminar flow to turbulent flow. Representative actuators discharging the energy can be arranged in a two-dimensional array of individually addressable actuators.

Abstract: A device and methods for low speed performance improvement of a lifting surface assembly are disclosed. At least one vortex generator is coupled to the lifting surface assembly, and the vortex generator is extended through the lifting surface assembly by drooping a hinged leading coupled to the lifting surface assembly to increase lift. The vortex generator is retracted inside the lifting surface assembly to decrease drag.

Abstract: Deployable aerodynamic devices with reduced actuator loads, and related systems and methods are disclosed. An external flow system in accordance with a particular embodiment includes an external flow body, a deployable device carried by and movable relative to the external flow body, and a coupling connected between the external flow body and the deployable device. The system can further include an actuator device operatively coupled between the external flow body and the deployable device, with the actuator device positioned to move the deployable device along a motion path between a stowed position and the deployed position. The motion path can have a first portion over which the load delivered by the actuator device increases as the deployed device moves toward the deployed position, and a second portion over which the load delivered by the actuator device decreases as the deployed device moves toward the deployed position.

Abstract: The invention relates to a vortex generator (10), in particular for a model (12) in a fluid-dynamic channel. In order to save time during the development of vehicles, in particular aircraft, in particular to save wind tunnel time, it is suggested to configure the vortex generator (10) switchable. Further, the invention relates to various uses of such a switchable vortex generator (10), in particular on models in fluid-dynamic channels and in fluid-dynamic channel tests.

Abstract: A method of monitoring the performance of an aerodynamic surface of an aircraft. The aircraft is operated during a non-perturbed measurement period such that the flow of air over the surface is at least partially laminar. A parameter is measured which is indicative of the drag of the surface during the non-perturbed measurement period to provide non-perturbed drag data. Air flow is perturbed temporarily over the surface in a perturbed measurement period so that it undergoes a transition from laminar flow to turbulent flow. The parameter is also measured during the perturbed measurement period to provide perturbed drag data. The degree of laminar flow during the non-perturbed measurement period can then be estimated in accordance with the difference between the perturbed drag data and the non-perturbed drag data. An ice protection system can be used to perturb the air flow.

Abstract: A method and systems are disclosed for reducing fluid flow noise. The method and systems use a thermal mechanism to deploy a flap edge fence during landing and/or other operating conditions, and stow the flap edge fence during other operational conditions such as cruise. The flap edge fence is controlled passively by ambient temperature or actively by a controller based on temperature changes corresponding to various operating conditions.

Abstract: A rotor blade assembly and a method for adjusting a loading capability of a rotor blade are disclosed. The rotor blade assembly includes a rotor blade having surfaces defining a pressure side, a suction side, a leading edge, and a trailing edge extending between a tip and a root. The rotor blade further defines a span and a chord. The rotor blade assembly further includes a spoiler assembly operable to alter a flow past a surface of the rotor blade. The spoiler assembly is incrementally deployable from the surface along one of a length or a width of the spoiler assembly.

Abstract: Embodiments relate to a Wingless Hovering Micro Air Vehicle and its Power Source Unit. Embodiments can operate at reasonable power levels for hovering and withstanding expected wind gusts. Embodiments can have a diameter less than 15 cm. Embodiments can have one or more smooth (continuous curvature) surface and can be operated using electromagnetic and electrohydrodynamic principles. The wingless design of specific embodiments can allow operation with no rotating or moving components. Additional embodiments can allow active response to the surrounding flow conditions. The issue of low lift to drag ratio and degradation of airfoil efficiency due to the inability of laminar boundary layers attachment can also be significantly reduced, or eliminated. The electromagnetic force can be generated by applying a pulsed (alternating/rf) voltage between a set of grounded and powered electrodes separated by a polymer insulator, dielectric, or other material with insulating properties.

Abstract: A vortex generator, or an array of vortex generators, for attenuating flow separation during flow of fluid over a surface. Vortex generators include a base with a forward end and a leading edge extending outward and rearward from the forward end to an outward end. The leading edge includes a first angular discontinuity at a height H1 above the base, and a second angular discontinuity at a height H2 above the base. The vortex generator(s) are configured for generating, adjacent a surface, at least two (2) vortices V1 and V2 in a fluid, and turning the outermost generated vortice toward the surface over which the fluid is passing.

Abstract: Systems to provide distributed flow control actuation to manage the behavior of a global flow field, are provided. An example of a system can include an aerodynamic structure having an outer surface, and an array of a plurality of nano-scale effectors connected to the outer surface of the aerodynamic structure to be in fluid contact with a flowing fluid when operationally flowing, to induce controlled, globally distributed disturbances at a viscous wall sublayer of a turbulent boundary layer of the flowing fluid when operationally flowing and to manipulate fluid behavior of the flowing fluid to thereby substantially reduce pressure loss associated with incipient separation of the fluid flow from portions of the aerodynamic structure.

Abstract: A device and methods for low speed performance improvement of a lifting surface assembly are disclosed. At least one vortex generator is coupled to the lifting surface assembly, and the vortex generator is extended through the lifting surface assembly by drooping a hinged leading coupled to the lifting surface assembly to increase lift. The vortex generator is retracted inside the lifting surface assembly to decrease drag.

Abstract: A boundary layer energizer (20) for energizing a boundary layer flow (33) over a surface (22), the boundary layer energizer (20) comprising one or more passages (24) terminating in one or more respective holes (26) provided on the surface (22), wherein the one or more passages (24) comprises at least one fin (25) configured so as to generate a vortex flow in the one or more passages (24) such that, when in use, a fluid emanating from the one or more passages (24) flows in a vortex.

Abstract: Systems and methods for controlling fluid flow utilizing a synthetic jet actuator, are provided. An example of a synthetic jet actuator system includes a synthetic jet actuator including a dual bimorph subsystem to provide low, medium, and high synthetic jet velocities and/or fine flow control response, and an arc-forming subsystem to provide enhanced pressure, velocity, and mass flow performance, enhanced flow control response, and/or heating of the fluid within the bimorph chamber to extend the performance or operating margin of the dual bimorph subsystem of the synthetic jet actuator. The arc-forming subsystem includes a pair of electrodes interfaced with inner surface walls of the dual bimorph subsystem. Various configurations of power supplies can be utilized to provide simultaneous function to both the subsystem and the arc-forming subsystem to allow selective activation.

Abstract: Systems, method, devices and apparatus are provided for reducing drag and increasing the flight efficiency characteristics of aircraft and airships including hybrid aircraft utilizing distributed boundary layer control and propulsion devices. Boundary layer control includes passive systems such as riblet films and boundary layer propulsion devices having a divided and distributed propulsion system disposed in the curved aft sections of aircraft and airships including hybrid aircraft susceptible to boundary layer drag due to degree of curvatures, speed and density of the surrounding air. Distributed propulsion devices include constructing propellers and riblets from shape memory alloys, piezoelectric materials and electroactive polymer (EAP) materials to change the shape and length of the distributed propulsion device.

Abstract: An oscillatory vorticity generator device for controlling the flow on an aero- or hydrodynamic surface of an element, the oscillatory vorticity generator device comprising: two main walls, positioned opposite to each other, forming a first pair of walls and two other walls, the four walls each having proximal and distal ends, the distal ends connected to an aero- or hydrodynamic surface; a connection connecting the walls at their proximal ends; and an opening in the aero- or hydrodynamic surface, the opening being substantially contiguous with the two main walls and the two other walls.

Abstract: A smart vortex generator including a main body, disposed on a body surface, such as a main wing of aircraft, making a boundary to a flow of fluid, and at least a part of which includes a shape memory alloy. A form of the main body, depending on a temperature increment/decrement of the fluid, changes between (1) a first form capable of suppressing a flow separation by a vortex generation and (2) a second form capable of suppressing a turbulent flow, by a phenomenon that the shape memory alloy undergoes a phase transformation between a high-temperature-side stable phase and a low-temperature-side stable phase. The smart vortex generator demonstrates a multi-directional characteristic depending on a temperature change, such that no energy supply from the outside is required. The structure is simple, and repairs and maintenance as well as installation to existing wings are easy.

Abstract: Systems and methods to provide distributed flow control actuation to manage the behavior of a global flow field, are provided. An example of a system can include an aerodynamic structure having an outer surface, and an array of a plurality of effectors connected to the outer surface of the aerodynamic structure to be in fluid contact with a flowing fluid when operationally flowing, to induce controlled, globally distributed disturbances at a viscous wall sublayer of a turbulent boundary layer of the flowing fluid when operationally flowing and to manipulate fluid behavior of the flowing fluid to thereby substantially reduce pressure loss associated with incipient separation of the fluid flow from portions of the aerodynamic structure.

Abstract: Systems and methods for controlling air vehicle boundary layer airflow are disclosed. Representative methods can include applying electrical energy bursts and/or other energy bursts in nanosecond pulses in the boundary layer along a surface of an air vehicle. In a particular embodiment, electrical energy is discharged into the boundary layer to reduce the tendency for the boundary layer to separate and/or to reduce the tendency for the boundary layer to transition from laminar flow to turbulent flow. In other embodiments, energy can be discharged via pulses having a pulse width of about 100 nanoseconds or less, and an amplitude of about 10,000 volts or more. Actuators discharging the energy can be arranged in a two-dimensional ray of individually addressable actuators. Energy can be delivered to the boundary layer via a laser emitter, and energy can be received in a receiver after having transited over at least a portion of the airflow surface.

Abstract: An aircraft with an outer surface from which flows an aerodynamic stream of cold air and includes at least one hot gas outlet, characterized in that it includes at least one device (16) for generating aerodynamic disturbances so as to mix hot gas and cold air, whereby the at least one device is connected to an outer surface (10) for protection against the heat and/or close to a hot gas outlet (12).

Abstract: A rotor blade for a wind turbine is disclosed. The rotor blade may generally include a shell having a pressure side and a suction side. The shell may define an opening in at least one of the pressure and suction sides. The rotor blade may also include a base and at least two surface features spaced apart along the outer perimeter of the base. The base may generally be movable relative to the opening between a recessed position and an actuated position. Additionally, the base may be rotatable within the shell in order to adjust which of the surface features is received within the opening when the base is moved to the actuated position.

Abstract: An active vortex control system (AVOCS) includes a set of primary injectors that inject gas into a cavity to generate a vortex in front of and possibly around components inside the cavity. The vortex interferes with an external flow field in an opening to the cavity to protect the components from the external environment. Sets of secondary injectors may inject gas at a reduced mass flow into the cavity to compensate for energy losses to maintain the coherence of the vortex. The AVOCS is well suited for use in windowless endo- and exo-atmospheric interceptors to protect the electro-optical imagers and optical components from Earth atmosphere.

Abstract: Aircraft wings are provided with aerodynamic devices that improve the wing's low airspeed aerodynamics. In preferred embodiments, the aircraft wings include a slat operatively positioned at the wing's leading edge for movement between a retracted position for relatively high airspeed aircraft operations, and a deployed position for relatively low airspeed aircraft operations. An aerodynamic device is positionally fixed to the wing laterally adjacent the leading edge slat, the device having a forward end extending forwardly of the wing leading edge. The device is operable in response to movement of the slat into the deployed position thereof so as to improve the aerodynamics of the wing at low airspeed aircraft operations, but provides substantially no aerodynamic improvement when the slat is in the retracted position thereof during high airspeed aircraft operations.

Abstract: A retractable chine assembly includes at least one chine which is hingebly mountable to a surface such as of an aircraft having a wing. The chine is preferably configured to be movable between stowed and deployed positions. The aircraft may include an engine nacelle which may be mounted on an underside of the wing. The nacelle may generate a nacelle wake that passes over the wing upper surface at high angles of attack and induces flow separation. The chine is preferably configured such that a vortex generated thereby interacts which the nacelle wake to delay flow separation and stall.

Abstract: A wind turbine blade has a suction side surface and a pressure side surface. A plurality of dynamic vortex elements are formed on at least one of the suction side or the pressure side surfaces. The vortex elements are activatable between a first retracted position that is inwardly recessed relative to a neutral plane of the surface on which they are formed and a second extended position that is outwardly protruding relative to the neutral plane of the surface.

Abstract: An apparatus for generating vortexes in fluid flow generally adjacent to a surface includes: (a) at least one vortex generating element; and (b) a piezoelectric motor element coupled with the at least one vortex generating element. The piezoelectric motor element responds to a varying voltage signal to move the at least one vortex generating element between a first position extending into the fluid flow an operating distance from the surface and a second position generally flush with the surface.

Abstract: The present invention provides a system and method for actively manipulating and controlling aerodynamic or hydrodynamic flow field vortices within a fluid flow over a surface using micro-jet arrays. The system and method for actively manipulating and controlling the inception point, size and trajectory of flow field vortices within the fluid flow places micro-jet arrays on surfaces bounding the fluid flow. These micro-jet arrays are then actively manipulated to control the flow behavior of the ducted fluid flow, influence the inception point and trajectory of flow field vortices within the fluid flow, and reduce flow separation within the primary fluid flow.

Abstract: A system for reducing overall drag of a mobile platform includes a surface on which an airflow forms a boundary layer and a generally normal shockwave. The airflow is at a first velocity that is one of transonic and supersonic. An oscillating jet injects and extracts a jet flow through the surface. The jet flow is at a second velocity that is substantially less than the first velocity. A recirculation region is upstream of the normal shockwave and is disposed at least partially in the boundary layer. The recirculation region is established at least by the oscillating jet. A generally oblique wave is established by the recirculation region and weakens the normal shockwave to reduce the overall drag experienced by the surface.

Abstract: Air induction control systems and methods for aircraft are provided. A particular aircraft includes a fuselage, a pair of wings and an engine. The aircraft also includes an inlet defining an aperture to receive air for delivery to the engine. The inlet has a longitudinal axis generally aligned with a direction of flow of the air as the air approaches the inlet. The aircraft also includes at least one first dielectric barrier discharge generator positioned to apply a first force to the air prior to the air being received by the engine. The first force acts in a first direction. The aircraft further includes at least one second dielectric barrier discharge generator positioned to apply a second force to the air prior to the air being received by the engine. The second force acts in a second direction that is non-parallel to the first direction.

Abstract: An aircraft (1) comprising: a fuselage (2), opposing wings (3, 4) either side of the fuselage (2), each wing (3, 4) supports at least one tangential flow rotor (5) and has a rotational axis. At least one tail section (3A) is disposed on each wing (3, 4) for forming a wing trailing edge. The tail sections (3A) are moveable about the, or each, rotor axis (X) relative to the fuselage (2) so as to provide, in use of said aircraft (1), variable thrust forces, whereby in use, movement of the or each tail section (3A) controls the flight of the aircraft (1). Lift is generated by way of a shroud (12) which forms an extension to the tail section (3A) curved surface or cowl to jointly cover a proportion of the circumference of the rotor. Ideally the shroud (12) and tail section curved surfaces create a vortex chamber generally within the rotor. An alternative embodiment includes a vertical axis fan (6) is provided on the fuselage (2) to adjust aircraft “pitch”.

Abstract: A flow control device is disclosed including a flow control surface over which fluid is designed to flow in a predetermined direction. Vortex generators are associated with the flow control surface. Each respective vortex generator has a pivot axis that forms an acute angle with respect to the predetermined direction and is capable of being positioned in both of an extended state, in which the respective vortex generators function to create a swirling fluid flow, and a retracted state, in which the respective vortex generators are pivoted via the pivot axis so as to lie adjacent to the flow control surface. An actuator is associated with each of the vortex generators, each actuator adapted to position the associated vortex generator between the extended and retracted states. The flow control device is disclosed to be used in tiltrotor vehicles.

Abstract: A device for controlling a vortex trail generated by an oblong element of an aircraft bearing surface includes a control component arranged on a fixing element of the oblong element and on a bearing surface such that a base of the control component contacts the leading edge of the bearing surface. The control component has a triangular shape, on a plane perpendicular to the longitudinal axis thereof, whose two adjacent sides form flanks interconnected by a rounded edge.

Abstract: A method and system to optimize the process a spreading the weight of supersonic aircraft downstream over a large area to reduce the pressure and intensity on the ground as function of air flow velocity, temperature, and/or pressure is provided.

Abstract: This invention relates to an element (11) for generating a fluid dynamic force, the element (11) comprising first (13) and second (15) surfaces extending in opposite directions from a leading edge (17) of the element (11) and meeting at a trailing edge (18) thereof to define a three dimensional body that is shaped to generate a fluid dynamic force when immersed at an angle of attack ? to a fluid flow over the element (11) in a flow direction U, the first surface (13) comprising an array of fluid inlets (19) and the second surface (15) comprising a corresponding array of fluid outlets (21), each said inlet (19) being fluidly coupled to a said outlet (21) by means of a fluid duct (23) at least part of which is pitched at an angle ? to a tangent plane (Y-Y) to said second surface (15) in the vicinity of said outlet (21) and skewed at an angle ? to said fluid flow direction U, the arrangement being such that the element (11) is operable in use to generate a relatively high fluid pressure region downstream of said

Abstract: Systems and methods for modifying fluid flowing over solid bodies are provided. A representative system incorporates a vorticity concentration-producing component and a synthetic jet actuator. The vorticity concentration-producing component is disposed on a pressure side of the solid body. The fluid flowing over the solid body remains attached to a surface of the solid body in a vicinity of the vorticity concentration-producing component. The synthetic jet actuator includes a jet housing that incorporates an internal chamber with a volume of fluid and an opening in the jet housing connecting the internal chamber to an external environment having the fluid.

Abstract: Runway length requirement for take-off and landing of an aircraft is reduced by taking advantage of dynamic lift overshoot, and in some cases, dynamic stall. In take-off and landing, the angle of attack is rapidly increased so that the lift coefficient exceeds the maximum predicted by the steady flow lift curve. By increasing the angle of attack at an appropriate rate, the increased lift coefficient can be maintained, without loss of control, until the aircraft touches down in the case of a landing, or until the aircraft can begin a normal climb, in the case of take-off. A low aspect ratio lifting body is preferred because of its more gradual stall behavior, and the potential to use dynamic stall for further deceleration before touchdown. Vortex fences can be oscillated to delay the onset of stall, and, in cruise, to energize the boundary-layer and reduce drag and/or control roll and/or yaw.

Abstract: The present invention relates to the improvement of the aerodynamic properties of bluff-body shaped ground vehicles. A least one air modulator is assembled on the vehicle to modify an air flow around the vehicle, such that the drag on the vehicle is decreased. Each air modulator has an array of openings including a number of openings, which are arranged next to one another along an essentially straight line. A control unit controls the at least one air modulator output oscillating air from each opening such that air vortices are formed outside the opening. The at least one air modulator is arranged on the vehicle, such that these air vortices have axes that, in proximity to the opening, are essentially perpendicular to a forward driving direction of the vehicle.

Abstract: A system for reducing distortion at the aerodynamic interface plane of a boundary-layer-ingesting inlet using a combination of active and passive flow control devices is disclosed. Active flow control jets and vortex generating vanes are used in combination to reduce distortion across a range of inlet operating conditions. Together, the vortex generating vanes can reduce most of the inlet distortion and the active flow control jets can be used at a significantly reduced control jet mass flow rate to make sure the inlet distortion stays low as the inlet mass flow rate varies. Overall inlet distortion, measured and described as average SAE circumferential distortion descriptor, was maintained at a value of 0.02 or less. Advantageous arrangements and orientations of the active flow control jets and the vortex generating vanes were developed using computational fluid dynamics simulations and wind tunnel experimentations.

Abstract: A method and systems are disclosed for reducing fluid flow noise. The method and systems use a thermal mechanism to deploy a flap edge fence during landing and/or other operating conditions, and stow the flap edge fence during other operational conditions such as cruise. The flap edge fence is controlled passively by ambient temperature or actively by a controller based on temperature changes corresponding to various operating conditions.

Abstract: An air induction system for an aircraft to control distortion and pressure recovery for improved aerodynamic performance. The system includes an inlet and at least one dielectric barrier discharge generator positioned upstream of the engine for imparting momentum to a low-energy boundary layer of air. A plurality of spaced dielectric barrier discharge generators may be activated in selected combinations to optimize performance at respective flight conditions. In one embodiment, one or more generators may be oriented generally transverse relative to the flow of intake air to eject the boundary layer in a lateral direction and prevent its ingestion by the engine. In another embodiment, one or more generators may be oriented along the direction of flow to accelerate the boundary layer air.

Abstract: According to the invention, a device for the generation of eddies creates or destroys eddies in a flowing medium in a particularly simple manner, with particularly low energy requirement with the lowest possible pressure drop, whereby the device comprises one or more profiles, for the flowing medium to flow around, which are provided with an external drive for a periodic movement relative to the flowing medium with an angular frequency ?. The profiles are thus periodically displaced with an angular frequency ? by an external drive.