摘要:
Lift produced by an airfoil of an aircraft is increased by suppressing fluid detachment from the surface of the airfoil. An engine cowling extends outwardly from the surface of the airfoil that has an exit plane configured for directing exhaust gases toward a rear of the aircraft. Fences extending outwardly from the surface and proximate to the exit plane of the engine cowling are configured to guide the exhaust gases along at least a portion of the airfoil surface, thereby restricting spanwise movement of the gases and increasing the Coanda Effect exhibited by the gases, thereby increasing the amount of lift produced along the surface of the airfoil. Such techniques may be used in short take-off and landing (STOL) aircraft.
摘要:
Coanda Effect and lift produced along a surface of an airfoil are increased by ducting compressed fluid from the engine to the surface of the airfoil. An engine produces exhaust gases that are predominantly directed toward an aft end of the aircraft by a cowling or other structure as an exhaust plume. One or more internal ducts extend from the engine to the surface of the airfoil to thereby transmit a compressed fluid from the engine to the surface in order to suppress flow separation along the surface, thereby causing the engine exhaust flow to remain attached to the surface over a wider span. Such structures and techniques may find particular use in aircraft designed to exploit upper surface blowing (USB) techniques and structures for short takeoff and landing (STOL) performance.
摘要:
A propulsion system for an aircraft includes an airfoil, an engine having an engine cowling carried by the airfoil and configured to produce exhaust gases that are predominantly directed toward an aft end of the airfoil by the engine cowling as engine exhaust, a propulsion flap carried by the airfoil and disposed aft of the engine cowling and a plurality of exhaust ejection orifices provided in the propulsion flap and adapted to receive at least a portion of the exhaust gases from the engine cowling.
摘要:
Lift produced by an airfoil of an aircraft is increased by suppressing fluid detachment from the surface of the airfoil. An engine cowling extends outwardly from the surface of the airfoil that has an exit plane configured for directing exhaust gases toward a rear of the aircraft. Fences extending outwardly from the surface and proximate to the exit plane of the engine cowling are configured to guide the exhaust gases along at least a portion of the airfoil surface, thereby restricting spanwise movement of the gases and increasing the Coanda Effect exhibited by the gases, thereby increasing the amount of lift produced along the surface of the airfoil. Such techniques may be used in short take-off and landing (STOL) aircraft.
摘要:
Coanda Effect and lift produced along a surface of an airfoil are increased by ducting compressed fluid from the engine to the surface of the airfoil. An engine produces exhaust gases that are predominantly directed toward an aft end of the aircraft by a cowling or other structure as an exhaust plume. One or more internal ducts extend from the engine to the surface of the airfoil to thereby transmit a compressed fluid from the engine to the surface in order to suppress flow separation along the surface, thereby causing the engine exhaust flow to remain attached to the surface over a wider span. Such structures and techniques may find particular use in aircraft designed to exploit upper surface blowing (USB) techniques and structures for short takeoff and landing (STOL) performance.
摘要:
Active systems and methods for controlling aircraft vortices are disclosed. An apparatus in accordance with one embodiment is directed to an aircraft system that includes an airfoil having first and second oppositely facing flow surfaces and a tip. The system can further include a vortex dissipation device carried by the airfoil, with the vortex dissipation device including an orifice positioned to direct a flow of fluid outwardly from the tip, an actuator operatively coupled to the fluid flow orifice and positioned to change a manner in which flow is directed outwardly from the tip, and a controller operatively coupled to the actuator to direct the operation of the actuator. The vortex dissipation device can be activated to accelerate the rate at which vortices (e.g., wing tip vortices) dissipate after they are generated, for example, by alternately pulsing flow inwardly and outwardly through the fluid flow orifice.
摘要:
Integrated engine exhaust systems and techniques for operating integrated engine exhaust systems are disclosed. In one embodiment, a propulsion system includes an engine installation configured to be mounted on a wing assembly of an aircraft. The engine installation includes an engine, and an exhaust system operatively coupled to the engine. The exhaust system includes at least one nozzle to exhaust an exhaust flow from the engine. The nozzle includes a variable portion configured to vary an exit aperture of the nozzle from a first shape to a second shape to change a flowfield shape of at least a portion of the nozzle flowfield proximate the wing assembly, thereby reducing at least one of drag and thermal loading on the wing assembly. In a further embodiment, the exhaust system includes an inner nozzle that exhausts a core exhaust flow, and an outer nozzle that exhausts a secondary exhaust flow, the outer nozzle having the variable portion configured to vary the exit aperture of the outer nozzle.
摘要:
A system and method for controlling boundary layer flow over an aircraft wing are provided. The system includes at least one wing element, and a plurality of ports defined in the wing element and in fluid communication with one another. The system also includes at least one fluidic device operable to continuously ingest the fluid through at least one of the ports and eject the fluid out of at least one other port to control boundary layer flow of the fluid over the wing element.
摘要:
Aircraft exhaust systems and methods are disclosed. In one embodiment, an integrated propulsion assembly includes a wing assembly having an upper surface and a lower surface, and a propulsion unit at least partially disposed within the wing assembly. An exhaust system is configured to conduct an exhaust flow emanating from the propulsion unit to an exhaust aperture. The exhaust aperture is positioned proximate a trailing edge of the wing assembly, and has an aspect ratio of at least five. In further embodiments, the wing assembly includes a flap member moveably coupled along a trailing edge portion of the wing assembly, and the exhaust aperture is configured to direct the exhaust flow over at least a portion of the flap member.
摘要:
The active system for the wide area suppression of a ground vortex generated by the engine of an aircraft includes an actuator assembly in fluid communication with a fluid source; and, at least one nozzle assembly, including at least one movable nozzle. The movable nozzle is in fluid communication with the actuator assembly for receiving fluid from the actuator assembly. The actuator assembly controls the motion of the movable nozzle, wherein fluid is injected over a desired region relative to an inlet of the engine to disrupt the flow structure of a ground vortex, thus mitigating ground vortex ingestion. This ensures the operational health of the engine during airplane maneuvering on the ground.