Sound absorbing structure having one or more acoustic scatterers for improved sound transmission loss

Patent metadata

Field	Value
Publication number	US-11555280-B2
Application number	US-202017036778-A
Country	US
Kind code	B2
Filing date	Sep 29, 2020
Priority date	Sep 29, 2020
Publication date	Jan 17, 2023
Grant date	Jan 17, 2023

Abstract

A sound absorbing structure includes a wall having a first side and a second side and at least one acoustic scatterer coupled to a first side of the wall. The first side of the wall may be positioned to face a source of noise, such as moving motor vehicles, airplanes, and the like. The at least one acoustic scatterer has an opening and at least one channel. The at least one channel has a channel open end and a channel terminal end with the channel open end being in fluid communication with the opening.

First claim

What is claimed is:

1. A sound absorbing structure comprising:
a wall having a first side and a second side, the first side of the wall being positioned to face a source of a noise;
at least one acoustic scatterer coupled to a first side of the wall, the at least one acoustic scatterer having a resonant frequency;
the at least one acoustic scatterer having an opening, a first channel and a second channel;
the first channel has a first channel open end and a first channel terminal end, the first channel open end being in fluid communication with the opening;
the second channel has a second channel open end and a second channel terminal end, the second channel open end being in fluid communication with the opening;
the first channel terminal end and the second channel terminal end are separate from one another; and
wherein the first channel and the second channel extend parallelly along the length of the at least one acoustic scatterer.

2. The sound absorbing structure of claim 1 , wherein the at least one acoustic scatterer has a flat side, the flat side being coupled to the first side of the wall.

3. The sound absorbing structure of claim 2 , wherein the at least one acoustic scatterer has a non-planar side, the non-planar side having the opening, the non-planar side substantially facing the source of the noise.

4. The sound absorbing structure of claim 3 , wherein the at least one acoustic scatterer has a half-cylinder shape, the half-cylinder shape defining the non-planar side and the flat side.

5. The sound absorbing structure of claim 1 , wherein the first channel and the second channel are shaped in a zigzag design.

6. The sound absorbing structure of claim 1 , wherein a thickness of the sound absorbing structure has a thickness of approximately 1/16 of a wavelength of a sound wave absorbed by the sound absorbing structure.

7. The sound absorbing structure of claim 1 , wherein the at least one acoustic scatterer comprises a plurality of acoustic scatters.

8. The sound absorbing structure of claim 7 , wherein the plurality of acoustic scatters includes a first scatterer having a first resonant frequency and a second scatterer having a second resonant frequency.

9. The sound absorbing structure of claim 1 , wherein the sound absorbing structure is configured to absorb sound waves at a certain frequency generated by the source of the noise, wherein the certain frequency is substantially similar to the resonant frequency of the at least one acoustic scatterer.

10. The sound absorbing structure of claim 9 , wherein the sound absorbing structure is configured to absorb sound waves generated by the source of the noise and projected towards the sound absorbing structure at an incidence angle substantially between 0 degrees and 45 degrees.

11. The sound absorbing structure of claim 10 , wherein:
the at least one acoustic scatterer includes a plurality of acoustic scatterers separate from each other by a distance; and
wherein the incidence angle of the sound waves absorbed by the sound absorbing structure varies based on a distance between a plurality of acoustic scatterers.

12. The sound absorbing structure of claim 11 , the incidence angle of the sound waves absorbed by the sound absorbing structure increases as a distance between the plurality of acoustic scatterers decreases.

13. The sound absorbing structure of claim 1 , wherein the wall is made of a rigid material.

14. The sound absorbing structure of claim 1 , wherein the first side of the wall faces a highway.

15. The sound absorbing structure of claim 1 , wherein the first side of the wall faces a runway of an airport.

16. A system from reducing noise generated by one or more vehicles, the system comprising;
a surface that supports the one or more vehicles;
a wall adjacent to and extending along a length of the surface, the wall having a first side and a second side, the first side faces towards the surface;
at least one acoustic scatterer coupled to a first side of the wall, the at least one acoustic scatterer having a resonant frequency;
the at least one acoustic scatterer having an opening, a first channel and a second channel;
the first channel has a first channel open end and a first channel terminal end, the first channel open end being in fluid communication with the opening;
the second channel has a second channel open end and a second channel terminal end, the second channel open end being in fluid communication with the opening;
the first channel terminal end and the second channel terminal end are separate from one another; and
wherein the first channel and the second channel extend parallelly along the length of the at least one acoustic scatterer.

17. The system of claim 16 , wherein the at least one acoustic scatterer has a flat side and a non-planar side, the flat side being coupled to the first side of the wall and the non-planar side having the opening.

18. The system of claim 16 , wherein the one or more vehicles are at least one of aircraft, watercraft, motor vehicles, and railed vehicles.

19. The sound absorbing structure of claim 1 , wherein the first and second channel terminal ends each form separate chambers.

20. The system of claim 16 , wherein the first and second channel terminal ends each form separate chambers.

Assignees

• Toyota Eng & Mfg North America

Inventors

• Su Xiaoshi
• Banerjee Debasish

Classifications

• E01F8/0052

  Grate-style, e.g. as wall facing · CPC title

• B64F1/26 Primary

  for reducing engine or jet noise; Protecting airports from jet erosion · CPC title

• E01F8/0047

  with open cavities, e.g. for covering sunken roads · CPC title

• E01F8/0023 Primary

  Details, e.g. foundations (solar cells specially adapted to be used in motorway sound barriers H02S20/21) · CPC title