CN108922510B - Mixed sound absorption structure with porous sound absorption material and resonance structure connected in parallel - Google Patents
Mixed sound absorption structure with porous sound absorption material and resonance structure connected in parallel Download PDFInfo
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- CN108922510B CN108922510B CN201810791875.6A CN201810791875A CN108922510B CN 108922510 B CN108922510 B CN 108922510B CN 201810791875 A CN201810791875 A CN 201810791875A CN 108922510 B CN108922510 B CN 108922510B
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- sound absorption
- porous sound
- sound absorbing
- resonant cavity
- absorbing material
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/162—Selection of materials
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects
Abstract
The invention discloses a broadband mixed sound absorption structure formed by connecting porous sound absorption materials and a resonance sound absorption structure in parallel, wherein the sound absorption frequency band of the broadband mixed sound absorption structure is wider than that of the porous sound absorption structure, the broadband mixed sound absorption structure has better sound absorption effect, and the positions of low frequency and high sound absorption effect can be adjusted according to actual needs. The parallel hybrid sound absorption structure comprises a porous sound absorption material and a resonance sound absorption structure, and the resonance sound absorption structure is embedded into the porous sound absorption material, so that the whole sound absorption structure has no change in thickness. The resonance sound absorption structure has good sound absorption effect on low frequency, a plurality of sound absorption peaks can be generated at the low frequency through the resonance sound absorption structures connected with a plurality of different resonance frequencies in parallel, and the whole parallel mixed sound absorption structure can ensure good sound absorption performance of the porous sound absorption material at medium and high frequencies and has good sound absorption effect at the low frequency.
Description
Technical Field
The invention relates to a sound absorption structure, in particular to a high-efficiency sound absorption structure with higher sound absorption coefficient in a wide frequency band range, which is used for aviation, navigation, vehicles and buildings.
Background
With the rapid development of vehicles such as aviation, navigation, automobiles and the like in China, the noise pollution problem is more obvious. At present, measures for noise reduction in these fields mainly include applying a sound absorbing material to the sound receiving surface to absorb sound wave energy.
The existing sound absorption structures are various, but have the following defects in summary:
1 ] has a specific sound absorption frequency range; for example, the sound absorption frequency range is divided into a middle-high frequency band and relatively insensitive to low frequency sounds;
2, the sound absorption frequency band is narrower, and the sound absorption effect outside the peak value is obviously reduced
And 3, the performances of fireproof, anticorrosion, moistureproof lamps and the like are poor and the environmental pollution is serious, so that the application is limited by environmental conditions.
The problem described in 3 is not avoided, and the cost of some new materials is high, so that the new materials are not commonly used.
Disclosure of Invention
The invention aims to provide a hybrid sound absorption structure formed by connecting a porous sound absorption material, a resonant cavity and an insertion pipe in parallel.
The porous sound absorbing material is a hollow cylinder. The hollow cylinder has a cylinder interior. One end of the hollow cylinder is an open end, and the other end is a circular bottom surface.
The resonant cavity is a hollow cylinder matching the inner cavity of the porous sound absorbing material. The porous sound absorbing material is sleeved outside the resonant cavity. One end of the resonant cavity is an open end flush with the open end, and the other end of the resonant cavity is a bottom end in contact with the bottom of the resonant cavity.
The open end and the open end are fixed on the wall surface.
The center of the bottom surface of the porous sound absorbing material is provided with a through hole. The bottom end of the resonant cavity is also provided with a through hole matched with the through hole on the bottom surface. The through hole is used for the insertion pipe to penetrate. The insertion tube is a cylindrical tube with two open ends. One end of the insertion tube is inserted into the resonant cavity, and the other end of the insertion tube is flush with the bottom surface.
It is worth noting that the adjustment of the sound absorption frequency band of low frequency is achieved by adjusting the length and diameter of the insertion tube. The height of the cylinder of the porous sound absorbing material is 70mm; the depth of the resonant cavity is 50mm; the diameter of the insertion tube is 20mm, and the length is 20-65 mm.
Further, the hybrid sound absorption structure connected with the resonance structure in parallel is characterized by comprising the porous sound absorption material, a plurality of resonance cavities and a plurality of insertion pipes.
The porous sound absorbing material is cuboid. One end of the cuboid is a lower end face, and the other end of the cuboid is an upper end face. The porous sound absorbing material is internally provided with a plurality of cylinder hollow inner cavities. The outlets of these hollow lumens are at the lower end face.
The resonant cavity is a hollow cylinder matching the inner cavity of the porous sound absorbing material. The number of the resonant cavities is the same as that of the inner cavities of the porous sound absorbing material. The porous sound absorbing material is sleeved outside the resonant cavity. One end of the resonant cavity is an opening end which is flush with the lower end face, and the other end of the resonant cavity is a bottom end which is contacted with the bottom of the resonant cavity.
The hybrid sound absorbing structure is mounted on a wall. The lower end face and the opening end are fixed on the wall face. The upper end face of the porous sound absorbing material is provided with through holes the same as the number of the resonant cavities. The bottom end of each resonant cavity is also provided with a through hole matched with the through hole on the upper end surface. The through hole is used for the insertion pipe to penetrate.
The insertion tube is a cylindrical tube with two open ends. The number of the insertion tubes is the same as the number of the resonant cavities. One end of each insertion tube is inserted into the resonant cavity, and the other end of each insertion tube is flush with the bottom surface.
The porous sound absorbing material is made of polyurethane foam material with the porosity of 0.75-0.90.
The parallel hybrid sound absorption structure has the following advantages:
1) The resonance sound absorption structure can form a sound absorption peak value at low frequency;
2) The resonant sound absorption frequency of the resonant sound absorption structure can be selected by adjusting the length of the insertion tube;
3) The sound absorption structure improves the low-frequency sound absorption coefficient and simultaneously ensures the high sound absorption coefficient of the medium-high-frequency porous sound absorption material.
Drawings
Fig. 1 is a schematic view of the basic structure of the parallel hybrid sound absorbing structure of the present invention.
Fig. 2 is a sound absorption plane formed by a plurality of basic structures connected in parallel.
Fig. 3 is a graph of sound absorption coefficient test comparisons for four different lengths of parallel hybrid sound absorption structure insert tubes.
In the figure: the wall surface (1), the porous sound absorbing material (2), the open end (201), the round bottom surface (202), the resonant cavity (3) and the insertion pipe (4); letter I points to the open end (201) and letter E points to the circular bottom surface (202); letters a and A-A are references to views.
A wall surface (10), a porous sound absorbing material (20), a lower end surface (2010), an upper end surface (2020), a resonant cavity (30), an open end (3010), a bottom end (3020) and an insertion tube (40); letters B and B-B are references to views.
Detailed Description
The present invention is further described below with reference to examples, but it should not be construed that the scope of the above subject matter of the present invention is limited to the following examples. Various substitutions and alterations are made according to the ordinary skill and familiar means of the art without departing from the technical spirit of the invention, and all such substitutions and alterations are intended to be included in the scope of the invention.
Example 1:
referring to fig. 1, a hybrid sound absorbing structure of a porous sound absorbing material and a resonance structure connected in parallel is characterized in that the hybrid sound absorbing structure is composed of a porous sound absorbing material 2, a resonance cavity 3 and an insertion pipe 4.
The porous sound absorbing material 2 is a hollow cylinder. The hollow cylinder has a cylinder interior. The hollow cylinder has an open end 201 at one end and a circular bottom surface 202 at the other end.
The resonant cavity 3 is a hollow cylinder matching the inner cavity of the porous sound absorbing material 2. The porous sound absorbing material 2 is sleeved outside the resonant cavity 3. The resonance cavity 3 has one end which is an open end 301 flush with the open end 201, and the other end which is a bottom end 302 contacting the bottom of the resonance cavity 3.
The open end 201 and the open end 301 are fixed to the wall 1.
The center of the bottom surface 202 of the porous sound absorbing material 2 has a through hole. The bottom end 302 of the resonant cavity 3 also has a through hole that mates with the through hole in the bottom surface 202. The through hole is used for the insertion tube 4 to penetrate. The insertion tube 4 is a cylindrical tube with two open ends. The insertion tube 4 has one end inserted into the resonant cavity 3 and the other end flush with the bottom surface 102. The resonant cavity 3 and the insertion tube 4 are both made of PVC tubes.
Fig. 3 is a graph of sound absorption coefficient test comparisons for four different lengths of parallel hybrid sound absorption structure insert tubes.
In this test, test equipment is Type 4206 impedance tube suite of B & K company, and sample parameters employed in the test are: the porous sound absorbing material is polyurethane foam with the porosity of 0.75-0.90, the diameter of the porous sound absorbing material is 100mm, and the height of the cylinder is 70mm; the diameter of the resonant cavity is 40mm, and the depth is 50mm; the diameter of the insertion tube of the resonant cavity is 20mm, and the lengths are 25mm, 31mm, 46mm and 50mm respectively.
Example 2:
referring to fig. 2, a hybrid sound absorbing structure of a porous sound absorbing material and a resonance structure connected in parallel, is characterized in that: the hybrid sound absorption structure connected with the resonance structure in parallel by the porous sound absorption material is characterized in that the hybrid sound absorption structure is composed of the porous sound absorption material 20, a plurality of resonance cavities 30 and a plurality of insertion pipes 40.
The porous sound absorbing material 20 is a rectangular parallelepiped. One end of the cuboid is a lower end face 2010, and the other end is an upper end face 2020. The porous sound absorbing material 20 has a plurality of cylindrical hollow cavities therein. The outlets of these hollow lumens are at the lower end face 2010.
The resonant cavity 30 is a hollow cylinder that mates with the interior cavity of the porous sound absorbing material 20. The number of resonant cavities 30 is the same as the number of inner cavities of the porous sound absorbing material 20. The porous sound absorbing material 20 is sleeved outside the resonant cavity 30. The cavity 30 has one end that is an open end 3010 that is flush with the lower end 2010 and the other end that is a bottom end 3020 that contacts the bottom of the cavity 30.
The hybrid sound absorbing structure is mounted on the wall 10. The lower end 2010 and the open end 3010 are fixed to the wall 10. The upper end 2020 of the porous sound absorbing material 20 has the same number of through holes as the number of the resonance chambers 30. The bottom end 3020 of each cavity 30 also has a through hole that mates with the through hole in the upper face 2020. The through hole is penetrated by the insertion tube 40.
The insertion tube 40 is a cylindrical tube with two open ends. The number of the insertion tubes 40 is the same as the number of the resonance chambers 30. One end of each insertion tube 40 is inserted into the resonance chamber 30, and the other end is flush with the bottom surface 1020. The resonant cavity 3 and the insertion tube 4 are both made of PVC tubes.
Claims (2)
1. A hybrid sound absorption structure with a porous sound absorption material and a resonance structure connected in parallel is characterized in that the hybrid sound absorption structure is composed of a porous sound absorption material (2), a resonance cavity (3) and an insertion pipe (4);
the porous sound absorbing material (2) is a hollow cylinder; the hollow cylinder has a cylinder inner cavity; one end of the hollow cylinder is an open end (201) and the other end is a round bottom surface (202);
the resonant cavity (3) is a hollow cylinder matched with the inner cavity of the porous sound absorbing material (2); the porous sound absorption material (2) is sleeved outside the resonant cavity (3); one end of the resonant cavity (3) is an open end (301) which is flush with the open end (201), and the other end is a bottom end (302) which is contacted with the bottom of the resonant cavity (3);
the open end (201) and the open end (301) are fixed on the wall surface (1);
the center of the bottom surface (202) of the porous sound absorbing material (2) is provided with a through hole; the bottom end (302) of the resonant cavity (3) is also provided with a through hole matched with the through hole on the bottom surface (202); the through hole is used for the insertion tube (4) to penetrate; the insertion tube (4) is a cylindrical tube with two open ends; one end of the insertion tube (4) is inserted into the resonant cavity (3), and the other end of the insertion tube is flush with the bottom surface (102); the porous sound absorbing material is polyurethane foam with the porosity of 0.75-0.90; the diameter of the insertion tube of the resonant cavity is 20mm, and the length is 25-50 mm.
2. The utility model provides a hybrid sound absorbing structure of porous sound absorbing material and resonance structure parallel which characterized in that: the composite sound absorption structure consists of a porous sound absorption material (20), a plurality of resonant cavities (30) and a plurality of insertion pipes (40);
the porous sound absorbing material (20) is cuboid; one end of the cuboid is a lower end face (2010), and the other end of the cuboid is an upper end face (2020); the porous sound absorbing material (20) is internally provided with a plurality of cylindrical hollow inner cavities; the outlets of these hollow lumens are at the lower end face (2010);
the resonant cavity (30) is a hollow cylinder matched with the inner cavity of the porous sound absorbing material (20); the number of the resonant cavities (30) is the same as that of the inner cavities of the porous sound absorbing material (20); the porous sound absorbing material (20) is sleeved outside the resonant cavity (30); one end of the resonant cavity (30) is an opening end (3010) which is flush with the lower end surface (2010), and the other end of the resonant cavity is a bottom end (3020) which is contacted with the bottom of the resonant cavity (30);
the hybrid sound absorbing structure is mounted on a wall (10); the lower end face (2010) and the opening end (3010) are fixed on the wall face (10); the upper end surface (2020) of the porous sound absorbing material (20) is provided with through holes the same as the number of the resonant cavities (30); the bottom end (3020) of each resonant cavity (30) also has a through hole matching the through hole in the upper end surface (2020); the through hole is used for the insertion tube (40) to penetrate;
the insertion tube (40) is a cylindrical tube with two open ends; the number of the insertion tubes (40) is the same as the number of the resonant cavities (30); one end of each insertion tube (40) is inserted into the resonant cavity (30), and the other end is flush with the bottom surface (102); the porous sound absorbing material is polyurethane foam with the porosity of 0.75-0.90; the diameter of the insertion tube of the resonant cavity is 20mm, and the length is 25-50 mm.
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| CN110397505A (en) * | 2019-07-11 | 2019-11-01 | 上海交通大学 | A kind of extension cast perforated plate honeycomb interlayer sound absorption structure |
| CN112447162A (en) * | 2019-08-29 | 2021-03-05 | 比亚迪股份有限公司 | Sound absorption structure design method, sound absorption structure and acoustic bag structure |
| CN112227237B (en) * | 2020-11-10 | 2022-04-29 | 广州地铁设计研究院股份有限公司 | Sound barrier containing air resonant cavity |
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