Flap side edge liners for airframe noise reduction
AssigneeThe United States of America as represented by the Administrator of the National Aeronautics and Space Administration
InventorsMichael G. Jones, Mehdi R. Khorrami, Meelan M. Choudhari, Brian M. Howerton
Life of this patent
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Abstract
One or more acoustic liners comprising internal chambers or passageways that absorb energy from a noise source on the aircraft are disclosed. The acoustic liners may be positioned at the ends of flaps of an aircraft wing to provide broadband noise absorption and/or dampen the noise producing unsteady flow features, and to reduce the amount of noise generated due to unsteady flow at the inboard and/or outboard end edges of a flap.
Claims20
A flap of the type that is movably connected to an aircraft wing to provide control of an aircraft in flight, the flap comprising:
- an elongated flap structure defining inboard and outboard ends and a leading edge and a trailing edge, the elongated flap structure further defining an upper side extending between the inboard and outboard ends and between the leading and trailing edges, and a lower side extending between the inboard and outboard ends and between the leading and trailing edges, wherein the upper side generally faces upwardly in use, and the lower side generally faces downwardly in use, and wherein the inboard end defines an inwardly-facing inboard end surface and the outboard end defines an outwardly-facing outboard end surface, and wherein the upper and lower sides define inboard and outboard end portions adjacent the inboard and outboard ends, respectively, that generate noise to form a noise source in use, and a spanwise central portion disposed on the upper and/or lower sides, extending between the inboard and outboard end portions and extending between the leading and trailing edges, wherein:
- at least a portion of the inboard and outboard end portions of at least one of the upper and lower sides includes a substantially porous portion that is acoustically connected to at least one acoustic chamber disposed within the elongated flap structure, wherein the spanwise central portion of the flap structure is non-porous, and wherein at least a portion of the noise from the noise source enters the acoustic chamber through the porous portion and is absorbed within the flap structure.
A flap of the type that is movably connected to an aircraft wing to provide control of an aircraft in flight, the flap comprising:
- an elongated flap structure defining inboard and outboard ends and a leading edge and a trailing edge extending between the inboard and outboard ends, the elongated flap structure defining an upper side extending between the inboard and outboard ends and between the leading and trailing edges, and a lower side extending between the inboard and outboard ends and between the leading and trailing edges, wherein the upper side generally faces upwardly in use, and the lower side generally faces downwardly in use, and wherein the inboard end defines an inwardly-facing inboard end surface and the outboard end defines an outwardly-facing outboard end surface, and wherein the upper and lower sides define inboard and outboard end portions adjacent the inboard and outboard ends, and wherein:
- the leading and trailing edges of at least one of the inboard and outboard end portions are non-porous and a central portion between said leading and trailing edges of said at least one of the inboard and outboard end portions includes a substantially porous portion that is acoustically connected to at least one acoustic chamber disposed within the elongated flap structure, and wherein at least a portion of the noise from the noise source enters the acoustic chamber through the porous portion and is absorbed within the flap structure.
A flap of the type that is movably connected to an aircraft wing to provide control of an aircraft in flight, the flap comprising:
- an elongated flap structure defining inboard and outboard ends and a leading edge and a trailing edge extending between the inboard and outboard ends, the elongated flap structure defining an upper side extending between the inboard and outboard ends and between the leading and trailing edges, and a lower side extending between the inboard and outboard ends and between the leading and trailing edges, wherein the upper side generally faces upwardly in use, and the lower side generally faces downwardly in use, and wherein the inboard end defines an inwardly-facing inboard end surface and the outboard end defines an outwardly-facing outboard end surface, and wherein the upper and lower sides define inboard and outboard end portions adjacent the inboard and outboard ends, and wherein:
- at least a portion of the inboard and outboard end surfaces includes a substantially porous portion that is acoustically connected to at least one acoustic chamber disposed within the elongated flap structure, and wherein at least a portion of the noise from the noise source enters the acoustic chamber through the porous portion and is absorbed within the flap structure.
Dependencies are inferred from the claim text.