Sound attenuation using a cellular core

Patent metadata

Field	Value
Publication number	US-9640164-B2
Application number	US-201514633514-A
Country	US
Kind code	B2
Filing date	Feb 27, 2015
Priority date	Feb 27, 2015
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

A method and apparatus for attenuating sound. Air, through which acoustic waves are traveling, is received within a core comprised of a plurality of cells. The sound created by the acoustic waves is attenuated using a set of channels through a number of cell interfaces between cells of the plurality of cells by allowing the air to flow between the cells of the plurality of cells through the set of channels.

First claim

What is claimed is:

1. An apparatus comprising:
a plurality of cells that form a core, wherein the plurality of cells comprises a number of layers of resin-impregnated fabric; and
a set of channels through a number of cell interfaces between cells of the plurality of cells in which the set of channels allows air to flow between the cells of the plurality of cells,
wherein the set of channels has a configuration designed such that the core acoustically performs within selected tolerances,
wherein the set of channels includes a first portion and a second portion, wherein the first portion of the set of channels each has at least one of a different size or a different shape than the second portion of the set of channels;
wherein the core has a first side, a second side opposite the first side, and a middle portion extending between the first side and the second side such that the first side and the second side are formed by the plurality of cells, and
wherein the channels are located in the middle portion a selected distance away from the first side and the second side.

2. The apparatus of claim 1 , wherein the air flowing between the cells creates cross-talk between at least three of the plurality of cells to attenuate sound.

3. The apparatus of claim 1 , wherein the core is configured for association with an aerospace vehicle.

4. The apparatus of claim 3 , wherein the configuration is designed to achieve a desired sound attenuation level during a selected phase of flight for the aerospace vehicle, wherein the selected phase of flight is selected from one of a takeoff phase and a landing phase.

5. The apparatus of claim 1 , wherein the core is configured for association with an engine system in an aerospace vehicle to attenuate sound generated by the engine system.

6. The apparatus of claim 1 , wherein the core is configured for association with a nacelle.

7. The apparatus of claim 1 further comprising:
a face sheet coupled to the core, wherein the face sheet is selected from one of an impervious face sheet and a porous face sheet.

8. The apparatus of claim 1 , wherein:
the first side is formed by a first portion of the plurality of cells; and
the second side is formed by a second portion of the plurality of cells.

9. The apparatus of claim 1 , wherein the plurality of cells is formed by a number of layers of material in which a layer in the number of layers of the material has a number of openings.

10. The apparatus of claim 1 , wherein the configuration for the set of channels includes at least one of a selected shape, a selected size, or a selected placement for at least one channel of the set of channels.

11. The apparatus of claim 1 , wherein the configuration is designed with respect to a set of acoustic parameters that determines an acoustic performance of the core, wherein the set of acoustic parameters includes at least one of impedance, resistance, reactance, or a sound attenuation level.

12. The apparatus of claim 1 , wherein the core having the set of channels between the cells of the plurality of cells forms a resonant device that provides a desired sound attenuation level.

13. A sound attenuation structure comprising:
a core, wherein the core comprises:
a plurality of cells having a selected geometry, wherein the plurality of cells comprises a number of layers of resin-impregnated fabric; and
a set of channels through a number of cell interfaces between cells of the plurality of cells in which the set of channels allows air to flow between the cells of the plurality of cells, wherein the set of channels has a configuration designed such that the core acoustically performs within selected tolerances, wherein the set of channels includes a first portion and a second portion, wherein the first portion of the set of channels each has at least one of a different size or a different shape than the second portion of the set of channels; and wherein the core has a first side, a second side opposite the first side, and a middle portion extending between the first side and the second side such that the first side and the second side are formed by the plurality of cells, and wherein the channels are located in the middle portion a selected distance away from the first side and the second side.

14. The sound attenuation structure of claim 13 further comprising:
a first face sheet coupled to the core; and
a second face sheet coupled to the core.

15. The sound attenuation structure of claim 14 , wherein the first face sheet is an impervious face sheet and the second face sheet is a porous face sheet.

16. The sound attenuation structure of claim 13 , wherein the core is a honeycomb core in which the selected geometry is a honeycomb geometry.

17. A method for attenuating sound, the method comprising:
receiving air through which acoustic waves are traveling within a core comprised of a plurality of cells, wherein the plurality of cells comprises a number of layers of resin-impregnated fabric; and
attenuating the sound created by the acoustic waves using a set of channels through a number of cell interfaces between cells of the plurality of cells by allowing the air to flow between the cells of the plurality of cells through the set of channels, wherein the set of channels includes a first portion and a second portion, wherein the first portion of the set of channels each has at least one of a different size or a different shape than the second portion of the set of channels; wherein the core has a first side, a second side opposite the first side, and a middle portion extending between the first side and the second side such that the first side and the second side are formed by the plurality of cells, and wherein the channels are located in the middle portion a selected distance away from the first side and the second side.

18. The method of claim 17 , wherein receiving the air comprises:
receiving the air through a face sheet coupled to the core, wherein the air flows through the face sheet into the core.

19. The method of claim 17 , wherein attenuating the sound comprises:
attenuating the sound created by the acoustic waves using the set of channels, wherein the set of channels has a configuration designed with respect to a set of acoustic parameters that determines an acoustic performance of the core, and wherein the set of acoustic parameters includes at least one of impedance, reactance, or a sound attenuation level.

Assignees

• Boeing Co

Inventors

• Gerken Noel Timothy
• Herrera Eric
• Duschl Garry Michael

Classifications

• G10K11/172 Primary

  using resonance effects · CPC title

• G10K11/002 Primary

  Devices for damping, suppressing, obstructing or conducting sound in acoustic devices (G10K1/06 - G10K1/10 take precedence; for electro-mechanical transducers for communication H04R3/002) · CPC title