Sound absorbers for airframe components

Patent metadata

Field	Value
Publication number	US-10501165-B2
Application number	US-201515535841-A
Country	US
Kind code	B2
Filing date	Dec 9, 2015
Priority date	Dec 18, 2014
Publication date	Dec 10, 2019
Grant date	Dec 10, 2019

Abstract

Sound absorbers and airframe components comprising such sound absorbers are disclosed. In one embodiment, an airframe component comprises an aerodynamic surface ( 48 ) and a sound absorber ( 38 ). The sound absorber ( 38 ) comprises a perforated panel ( 40 ) having a front side exposed to an ambient environment outside of the airframe component and an opposite back side. The panel ( 40 ) comprises perforations extending through a thickness of the panel for permitting passage of sound waves therethrough. The sound absorber ( 38 ) also comprises a boundary surface spaced apart from the perforated panel. The boundary surface and the back side of the perforated panel ( 40 ) at least partially define a cavity in the airframe component for attenuating some of the sound waves entering the cavity via the perforations in the perforated panel ( 40 ).

First claim

What is claimed is:

1. An airframe component of an aircraft, the airframe component comprising:
a skin defining an aerodynamic surface having a side edge; and
a sound absorber comprising:
a perforated panel disposed at or adjacent the side edge of the aerodynamic surface, the perforated panel having a front side exposed to an ambient environment outside of the airframe component and an opposite back side, the panel comprising perforations extending through a thickness of the panel for permitting passage of sound waves therethrough; and
a boundary surface spaced apart from the perforated panel, the boundary surface and the back side of the perforated panel at least partially defining a cavity in the airframe component for attenuating some of the sound waves entering the cavity via the perforations in the perforated panel;
wherein either the perforated panel or the boundary surface is defined by a rib of the airframe component, the rib supporting the skin and having a C-channel configuration.

2. The airframe component as defined in claim 1 , wherein a distance between the boundary surface and the back side of the perforated panel is between 1 cm and 10 cm.

3. The airframe component as defined in claim 1 , wherein an average cross-sectional dimension of the perforations is less than 1 mm.

4. The airframe component as defined in claim 1 , wherein the perforated panel has a perforation percentage between 0.5% and 10%.

5. The airframe component as defined in claim 1 , wherein the cavity is free of cellular structures.

6. The airframe component as defined in claim 1 , wherein the perforated panel is oriented transversely to the aerodynamic surface.

7. The airframe component as defined in claim 1 , wherein the airframe component comprises a high-lift device.

8. The airframe component as defined in claim 1 , wherein the airframe component comprises a flap.

9. The airframe component as defined in claim 1 , wherein the airframe component comprises a slat.

10. The airframe component as defined in claim 1 , wherein the airframe component is deployable.

11. The airframe component as defined in claim 1 , wherein the airframe component comprises a fixed leading edge.

12. The airframe component as defined in claim 1 , wherein the boundary surface is defined by the rib and the perforated panel comprises a close-out plate of a high-lift device.

13. The airframe component as defined in claim 1 , wherein the boundary surface is defined by a wall that is attached to the perforated panel.

14. The airframe component as defined in claim 13 , wherein an air-tight seal is provided between the wall and the perforated panel.

15. The airframe component as defined in claim 13 , wherein the wall and the perforated panel have a unitary construction.

16. The airframe component as defined in claim 1 , wherein the perforated panel is a first perforated panel and the airframe component comprises a second perforated panel disposed between the first perforated panel and the boundary surface to form two internal sound-attenuating cavities in series between the back side of the first perforated panel and the boundary surface.

17. An aircraft comprising the airframe component defined in claim 1 .

18. An airframe component of an aircraft, the airframe component comprising:
a skin defining an aerodynamic surface;
a closing rib supporting the skin, the closing rib comprising perforations extending through a thickness of the closing rib for permitting passage of sound waves therethrough, the closing rib having a C-channel configuration; and
a boundary surface spaced apart from the closing rib, the boundary surface and the closing rib at least partially defining a cavity in the airframe component for attenuating some of the sound entering the cavity via the perforations in the closing rib.

19. The airframe component as defined in claim 18 , comprising a perforated panel disposed between the closing rib and the boundary surface to form two internal sound-attenuating cavities in series between the closing rib and the boundary surface.

20. The airframe component as defined in claim 18 , wherein the airframe component comprises a high-lift device.

21. The airframe component as defined in claim 18 , wherein the airframe component comprises a fixed leading edge.

22. The airframe component as defined in claim 18 , wherein the cavity is free of cellular structures.

23. An aircraft comprising the airframe component defined in claim 18 .

24. An airframe component of an aircraft, the airframe component comprising:
a skin defining an aerodynamic surface having a side edge; and
a close-out plate disposed at or adjacent the side edge of the aerodynamic surface, the close-out plate having a front side exposed to an ambient environment outside of the airframe component and a back side, the close-out plate comprising perforations extending through a thickness of the close-out plate for permitting passage of sound waves therethrough; and
a rib supporting the skin, the rib comprising a boundary surface spaced apart from the close-out plate, the boundary surface and the back side of the close-out plate at least partially defining a cavity in the airframe component for attenuating some of the sound waves entering the cavity via the perforations in the close-out plate, the rib having a C-channel configuration.

25. The airframe component as defined in claim 24 , wherein the airframe component comprises a high-lift device.

26. The airframe component as defined in claim 24 , wherein the airframe component comprises a fixed leading edge.

27. The airframe component as defined in claim 24 , wherein the cavity is free of cellular structures.

28. An aircraft comprising the airframe component defined in claim 24 .

Assignees

• Bombardier Inc

Inventors

• Wong Raymond Lee Man

Classifications

• B64C2230/24

  by using passive resonance cavities, e.g. without transducers · CPC title

• B64C2230/22

  by using a surface having multiple apertures of relatively small openings other than slots · CPC title

• B64C2230/08

  by influencing fluid flow by means of surface cavities, i.e. net fluid flow is null · CPC title

• B64C2230/14

  achieving noise reductions · CPC title

• B64D2033/0206

  comprising noise reduction means, e.g. acoustic liners · CPC title