Abstract: A method, apparatus, and system for managing airflow comprising flow control actuators in an aircraft. The flow control actuators comprise channels having inlets and outlets, wherein the channels are located under a surface of the aircraft and the outlets are in communication with the surface of the aircraft. Pressurized air applied to the inlets causes steady air jets to be emitted at the outlets in which the steady air jets add a momentum to airflow over the surface on the aircraft.

Abstract: Air acceleration at slot of aircraft wing. In one embodiment, a wing includes an air duct configured to transport air in a spanwise direction along a leading edge of the wing from an air supply source of the aircraft. The wing further includes a discharge duct configured to transport the air in an aft direction from the air duct to an aft end of the wing, and one or more nozzles disposed on the aft end of the wing and configured to accelerate air into a slot between the wing and a flap of the aircraft to increase lift and reduce drag for the wing.

Abstract: A fluidic actuator is configured to be mounted to an airfoil surface. The actuator includes a rotor supported within a housing. The rotor contains at least one generally radially extending nozzle that converges from an entry at an interior circumference of the rotor to an exit at an exterior circumference thereof, the converging shape of the nozzle assuring high velocity airflow at the nozzle exit. In one form, each nozzle also includes a curved path by which high-pressure air is enabled to induce spinning of the rotor. The fluidic actuator further includes a diffuser through which high-pressure air from the nozzles is cyclically ejected from those of the nozzles instantaneously exposed to the diffuser. In one form, the rotor spins at 300 revolutions per second and provides nozzle ejections effective to avoid boundary layer separation; i.e. to maintain an attached boundary layer flow over the airfoil.

Abstract: High-lift systems and related methods are described. An example apparatus includes a fixed wing and a Krueger flap movably coupled to the fixed wing between a stowed position and a deployed position. The Krueger flap includes a first flap portion movably coupled to the fixed wing and a second flap portion movable coupled to the first flap portion. The first flap portion moves relative to the second flap portion between a retracted position and an extended position. The first flap is to move to the retracted position in response to the Krueger flap moving to the stowed position. The first flap is to move to the extended position to define an aerodynamic surface in response to the Krueger flap moving to the deployed position.

Abstract: Air acceleration at slot of aircraft wing. In one embodiment, a wing includes an air duct configured to transport air in a spanwise direction along a leading edge of the wing from an air supply source of the aircraft. The wing further includes a discharge duct configured to transport the air in an aft direction from the air duct to an aft end of the wing, and one or more nozzles disposed on the aft end of the wing and configured to accelerate air into a slot between the wing and a flap of the aircraft to increase lift and reduce drag for the wing.

Abstract: Air acceleration at leading edge of aircraft wing. In one embodiment, a slat disposed along a leading edge of a wing of an aircraft. The slat includes a skin structure having an aerodynamic shape, and a hollow space within the skin structure. The slat further includes a nozzle disposed on the skin structure to accelerate air collected in the hollow space into an external environment outside the slat to increase lift and reduce drag for the wing.

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: Aircraft wing droop leading edge apparatus and methods are described. An example aircraft includes a wing having a front spar and an outer skin covering the front spar. The outer skin includes a forward portion located forward of the front spar. The forward portion of the outer skin includes a leading edge movable between a neutral position and a drooped position deflected downward relative to the neutral position. The forward portion of the outer skin has a continuous outer mold line when the leading edge is in the drooped position.

Abstract: Methods, apparatus, systems, and articles of manufacture are disclosed to improve fluid flow simulations. An example apparatus includes a property identifier to, prior to execution of the computer-based model, identify donors and recipients representative of one or more model regions of the computer-based model to simulate for a plurality of time steps including a first time step and a second time step, the donors having donor properties, in response to computing a flow field for the first time step of the computer-based model, a property extractor to extract the donor properties from extraction surfaces of the donors, and a property assignor to assign the donor properties to boundary surfaces of respective ones of the recipients, and a flow field generator to generate an output flow field for the second time step based on the recipients having the assigned donor properties.

Abstract: Flow control systems having movable slotted plates are disclosed. A disclosed example apparatus includes a flow control plate to be placed proximate an opening of an aerodynamic body. The opening has a first slot and the flow control plate has a second slot angled relative to the opening. The apparatus also includes an actuator to move the flow control plate relative to the opening in a linear oscillatory motion to vary a flow of fluid exiting the opening over the aerodynamic body. The flow of fluid is to flow from the second slot to the first slot.

Abstract: Aircraft wing droop leading edge apparatus and methods are described. An example aircraft includes a wing having a front spar and an outer skin covering the front spar. The outer skin includes a forward portion located forward of the front spar. The forward portion of the outer skin includes a leading edge movable between a neutral position and a drooped position deflected downward relative to the neutral position. The forward portion of the outer skin has a continuous outer mold line when the leading edge is in the drooped position.

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: High-lift systems and related methods are described. An example apparatus includes a fixed wing and a Krueger flap movably coupled to the fixed wing between a stowed position and a deployed position. The Krueger flap includes a first flap portion movably coupled to the fixed wing and a second flap portion movable coupled to the first flap portion. The first flap portion moves relative to the second flap portion between a retracted position and an extended position. The first flap is to move to the retracted position in response to the Krueger flap moving to the stowed position. The first flap is to move to the extended position to define an aerodynamic surface in response to the Krueger flap moving to the deployed position.

Abstract: Flow control systems having movable slotted plates are disclosed. A disclosed example apparatus includes a flow control plate to be placed proximate an opening of an aerodynamic body. The opening has a first slot and the flow control plate has a second slot angled relative to the opening. The apparatus also includes an actuator to move the flow control plate relative to the opening in a linear oscillatory motion to vary a flow of fluid exiting the opening over the aerodynamic body. The flow of fluid is to flow from the second slot to the first slot.

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: 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 fluidic actuator is configured to be mounted to an airfoil surface. The actuator includes a rotor supported within a housing. The rotor contains at least one generally radially extending nozzle that converges from an entry at an interior circumference of the rotor to an exit at an exterior circumference thereof, the converging shape of the nozzle assuring high velocity airflow at the nozzle exit. In one form, each nozzle also includes a curved path by which high-pressure air is enabled to induce spinning of the rotor. The fluidic actuator further includes a diffuser through which high-pressure air from the nozzles is cyclically ejected from those of the nozzles instantaneously exposed to the diffuser. In one form, the rotor spins at 300 revolutions per second and provides nozzle ejections effective to avoid boundary layer separation; i.e. to maintain an attached boundary layer flow over the airfoil.

Abstract: Example active flow control systems and methods for aircraft are described herein. An example active flow control system includes a plurality of nozzles arranged in an array across a surface of an aircraft. The nozzles are oriented to eject air across the surface to reduce airflow separation. The active flow control system also includes an air source coupled to the nozzles and a controller to activate the nozzles to eject air from the air source in sequence from outboard to inboard and then from inboard to outboard to create a wave of air moving from outboard to inboard and then from inboard to outboard across the surface.

Abstract: Example active flow control systems and methods for aircraft are described herein. An example active flow control system includes a plurality of nozzles arranged in an array across a surface of an aircraft. The nozzles are oriented to eject air across the surface to reduce airflow separation. The active flow control system also includes an air source coupled to the nozzles and a controller to activate the nozzles to eject air from the air source in sequence from outboard to inboard and then from inboard to outboard to create a wave of air moving from outboard to inboard and then from inboard to outboard across the surface.

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.