Abstract: Example active flow control systems and methods for aircraft are described herein. An example method includes supplying pressurized air to a plurality of nozzles. The nozzles arranged in an array across a control surface of an aircraft, and the nozzles are oriented to eject the pressurized air in a substantially streamwise direction. The method further includes activating the nozzles to eject the pressurized air in sequence to create a wave of air moving in a spanwise direction across the control surface.

Abstract: Methods and apparatus for reducing flow distortion at engine fans of nacelles are disclosed. An example apparatus for reducing flow distortion at an engine fan of a nacelle includes a plurality of nozzles radially spaced about an inner wall of the nacelle. In some examples, respective ones of the nozzles are positioned to eject corresponding respective jets of fluid adjacent the inner wall in a downstream direction toward the engine fan. The example apparatus further includes a controller to selectively activate the respective ones of the nozzles according to a time-based sequence. In some examples, the time-based sequence corresponds to a directional sequence that moves in an arcuate direction along a circumference of the inner wall.

Abstract: A method and apparatus are presented. An active flow control system comprises a flow control valve, a manifold, and a temperature control system. The flow control valve is configured to control a flow of air into the manifold. The manifold is operatively connected to a number of actuators. The temperature control system is configured to heat at least a portion of the flow of air.

Abstract: An aircraft, an aircraft wing structure and a method are provided in order to address lift and drag, such as by increasing lift and reducing drag. In the context of an aircraft wing structure, the aircraft wing structure includes a wing extending outboard from a fuselage of an aircraft. The wing also extends from a leading edge to a trailing edge. The aircraft wing structure also includes one or more actuators carried by the wing and causing fluid to be directed through one or more respective orifices defined by the wing so as to alter flow over a lower surface of the wing. The one or more orifices that are defined by the wing are closer to the leading edge than to the trailing edge. Thus, the fluid introduced through the one or more orifices may increase lift and reduce drag of the associated aircraft.

Abstract: A method and apparatus are presented. An active flow control system comprises a flow control valve, a manifold, and a temperature control system. The flow control valve is configured to control a flow of air into the manifold. The manifold is operatively connected to a number of actuators. The temperature control system is configured to heat at least a portion of the flow of air.

Abstract: A drag reduction system for an aircraft may include an air ejector having an ejection port located between an aft portion of an airfoil main element and a forward portion of a trailing edge device. The air ejector may be configured to discharge an air jet from the ejection port in such a manner that the air jet passes over the upper surface of the trailing edge device.

Abstract: Example active flow control systems and methods for aircraft are described herein. An example method includes supplying pressurized air to a plurality of nozzles. The nozzles arranged in an array across a control surface of an aircraft, and the nozzles are oriented to eject the pressurized air in a substantially streamwise direction. The method further includes activating the nozzles to eject the pressurized air in sequence to create a wave of air moving in a spanwise direction across the control surface.

Abstract: A method and apparatus are presented. An active flow control system comprises a flow control valve, a manifold, and a temperature control system. The flow control valve is configured to control a flow of air into the manifold. The manifold is operatively connected to a number of actuators. The temperature control system is configured to heat at least a portion of the flow of air.

Abstract: An aircraft, an aircraft wing structure and a method are provided in order to address lift and drag, such as by increasing lift and reducing drag. In the context of an aircraft wing structure, the aircraft wing structure includes a wing extending outboard from a fuselage of an aircraft. The wing also extends from a leading edge to a trailing edge. The aircraft wing structure also includes one or more actuators carried by the wing and causing fluid to be directed through one or more respective orifices defined by the wing so as to alter flow over a lower surface of the wing. The one or more orifices that are defined by the wing are closer to the leading edge than to the trailing edge. Thus, the fluid introduced through the one or more orifices may increase lift and reduce drag of the associated aircraft.

Abstract: Apparatus and methods for robust lift generation through flow separation suppression are disclosed. One example apparatus includes a cowling extending from a surface of a fluid dynamic body to provide an exhaust stream directed over the fluid dynamic body. The example apparatus also includes a fluid ejection slot proximate or on the fluid dynamic body, where the fluid ejection slot is to direct a compressed fluid along a surface of the fluid dynamic body. The example apparatus also includes rotatable vanes having blunt leading edges, where the vanes are proximate the fluid ejection slot to direct the compressed fluid to affect attachment of the exhaust stream to the fluid dynamic body to enhance lift.

Abstract: A system and method for robust lift generation through flow separation suppression are presented. A fluid flow is ejected over a lifting surface from a fluid ejection orifice, and a flow direction of the fluid flow over the lifting surface is directed using a plurality of vanes configured in the fluid ejection orifice. The flow direction is rotated in a span-wise direction over the lifting surface by swiveling the vanes.

Abstract: A drag reduction system for an aircraft may include an air ejector having an ejection port located between an aft portion of an airfoil main element and a forward portion of a trailing edge device. The air ejector may be configured to discharge an air jet from the ejection port in such a manner that the air jet passes over the upper surface of the trailing edge device.

Abstract: A system and method for robust lift generation through flow separation suppression are presented. A fluid flow is ejected over a lifting surface from a fluid ejection orifice, and a flow direction of the fluid flow over the lifting surface is directed using a plurality of vanes configured in the fluid ejection orifice. The flow direction is rotated in a span-wise direction over the lifting surface by swiveling the vanes.

Abstract: A system and methods for a self-rotating fluidic traverse actuator are presented. A turbine rotates in response to a fluid flow, and an outer cylinder with a longitudinal slot that ejects the fluid flow. An inner cylinder rotates inside the outer cylinder in response to a rotation of the turbine and at least one helical slot of the inner cylinder ejects the fluid flow into the longitudinal slot.

Abstract: Apparatus and methods for robust lift generation through flow separation suppression are disclosed. One example apparatus includes a cowling extending from a surface of a fluid dynamic body to provide an exhaust stream directed over the fluid dynamic body. The example apparatus also includes a fluid ejection slot proximate or on the fluid dynamic body, where the fluid ejection slot is to direct a compressed fluid along a surface of the fluid dynamic body. The example apparatus also includes rotatable vanes having blunt leading edges, where the vanes are proximate the fluid ejection slot to direct the compressed fluid to affect attachment of the exhaust stream to the fluid dynamic body to enhance lift.

Abstract: Systems and methods for reducing the trailing vortices and lowering the noise produced by the side edges of aircraft flight control surfaces, tips of wings and winglets, and tips of rotor blades. A noise-reducing, wake-alleviating device is disclosed which incorporates an actuator and one or more air-ejecting slot-shaped openings coupled to that actuator and located on the upper and/or lower surfaces and/or the side edges of an aircraft flight control surface or the tip of a wing, winglet or blade. The actuation mechanism produces sets of small and fast-moving air jets that traverse the openings in the general streamwise direction. The actuation destabilizes the flap vortex structure, resulting in reduced intensity of trailing vortices and lower airplane noise.

Abstract: A system and method for robust lift generation through flow separation suppression are presented. A fluid flow is ejected over a lifting surface from a fluid ejection orifice, and a flow direction of the fluid flow over the lifting surface is directed using a plurality of vanes configured in the fluid ejection orifice. The flow direction is rotated in a span-wise direction over the lifting surface by swiveling the vanes.

Abstract: Concepts and technologies described herein provide for a low noise aircraft wing slat system. According to one aspect of the disclosure, a wing slat is used in conjunction with upper and lower bridging elements to minimize airframe noise associated with a high lift system during takeoff and landing flight operations. An upper bridging element deploys from a slat or an aircraft wing during deployment of the slat for takeoff operations and creates a continuous aerodynamic surface between the slat and an upper surface of the wing leading edge to improve the airflow and reduce drag. A lower bridging element deploys from the wing during cruise flight to bridge a gap between a lower surface of a stowed leading edge slat and a lower surface of the wing. During landing operations, both upper and lower bridging elements remain stowed to optimize ambient airflow for noise abatement and lift creation.

Abstract: An apparatus for supplying a gas flow over an aerodynamic structure is provided. The apparatus includes a fluid source for supplying the gas flow and a flow control actuator configured to receive the gas flow from the fluid source. The flow control actuator is also configured to selectively direct the gas flow over the aerodynamic structure when the flow control actuator is in at least one predetermined operating position and to restrict the gas flow over the aerodynamic structure when the flow control actuator is in another of the predetermined operating positions.

Abstract: A system and methods for a self-rotating fluidic traverse actuator are presented. A turbine rotates in response to a fluid flow, and an outer cylinder with a longitudinal slot that ejects the fluid flow. An inner cylinder rotates inside the outer cylinder in response to a rotation of the turbine and at least one helical slot of the inner cylinder ejects the fluid flow into the longitudinal slot.