Compression-resistant broadband sound-absorbing tile filled with sound-absorbing material

Abstract

The present application relates to filled sound-absorbing material compression type broadband sound-absorbing tile, belonging to the technical field of sound-absorbing, damping and noise reduction, mainly composed of surface layer, mixed cavity layer and bottom layer, wherein the mixed cavity layer is composed of several groups of combined expansion ring resonant cavities and one cuboid cavity, the cuboid cavity structure is filled with porous sound-absorbing material; the surface layer is in contact with seawater and is made of rubber matched with the impedance of seawater, the mixed cavity layer is made of polyurethane rubber material, and the bottom layer is made of rubber material matched with the impedance of the shell of underwater submersible; the structure of the sound-absorbing tile can effectively absorb enemy active sonar sound waves, significantly reduce the active sonar action distance and sonar echo intensity, absorb underwater submersible self-noise, reduce underwater submersible radiation noise, and reduce the stress deformation of the cavity under high pressure underwater environment, and stabilize the performance of the tile.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of sound-absorbing equipment, specifically to a kind of filled sound-absorbing material compression type broadband sound-absorbing tile, belong to sound-absorbing, damping and noise reduction technical field. BACKGROUND

[0002] Underwater submersible due to large volume, and appearance is similar to the strong reflection of detection signal of cylindrical, elliptical cylindrical and other large targets to enemy active sonar, and due to the vibration of underwater submersible, such as propeller rotation, power equipment tremble, the radiation noise generated when power transmission of mechanical equipment is also one of the sources of high target intensity. Therefore, in order to shorten the active sonar range of enemy, reduce the radiation noise generated by underwater submersible, ensure the safety of underwater submersible, it is an effective means to lay sound-absorbing tile for underwater submersible.

[0003] In recent years, the sound-absorbing tile laid by underwater submersible is widely used in phononic crystal type and cavity structure type, wherein the resonance cavity structure is limited to horn cavity or exponential number cylinder. There are several limitations for the function realization of these two types of sound-absorbing tiles. First, there is a cutoff frequency or narrow sound-absorbing frequency band, which cannot maintain stable effect, and the sound-absorbing effect of low frequency sound wave is poor. Second, it cannot simultaneously consider the function of suppressing the radiation noise generated by the vibration of underwater vehicle itself. Third, the application effect of single sound-absorbing material is poor, and with the increase of the diving depth of underwater submersible, the cavity deformation of sound-absorbing tile increases, which leads to the decrease of sound-absorbing performance. SUMMARY

[0004] The present application provides a kind of filled sound-absorbing material compression type broadband sound-absorbing tile for the surface of underwater submersible in view of the problems existing in the prior art, which can widen the frequency band width, and can improve the compression resistance of itself. It not only can absorb the radiation noise of underwater vehicle, shorten the detection distance of enemy active sonar, but also can improve the safety and concealment of underwater vehicle navigation.

[0005] In order to achieve the above purpose, the technical scheme of the present application is as follows:

[0006] A kind of filled sound-absorbing material compression type broadband sound-absorbing tile, comprising a surface layer, a mixed cavity layer and a bottom layer, the surface layer is in contact with water, the bottom layer is in contact with the surface of underwater submersible, the mixed cavity layer is between the surface layer and the bottom layer, and a cuboid cavity and N groups of combined expansion ring-shaped resonance cavity are sequentially arranged on the side of the mixed cavity layer close to the bottom layer, N≥1, the cuboid cavity is filled with open-cell aluminum foam, and the N groups of combined expansion ring-shaped resonance cavity are connected with the cuboid cavity.

[0007] Preferably, the combined expansion ring resonant cavity comprises a cavity ring, a combined expansion ring resonant cavity upper layer cavity, a combined expansion ring resonant cavity lower layer cavity; the cavity ring comprises cavity ring A, cavity ring B, cavity ring C, cavity ring A is connected in sequence with the combined expansion ring resonant cavity upper layer cavity, cavity ring B, the combined expansion ring resonant cavity lower layer cavity, cavity ring C.

[0008] Preferably, the radius of the cavity ring is 1.5-2 mm; the radius of the combined expansion ring resonant cavity upper layer cavity is 2-2.5 times the radius of the cavity ring; the radius of the combined expansion ring resonant cavity lower layer cavity is 2.5-4 times the radius of the cavity ring.

[0009] Preferably, the interval between the two adjacent combined expansion ring resonant cavity lower layer cavities is 1-1.5 mm. In order to ensure that the structure of the combined expansion ring resonant cavities does not affect each other under deformation.

[0010] Preferably, the height of the surface layer and the bottom layer is 4-6 mm.

[0011] Preferably, the height of the mixed cavity layer is 8 times the height of the surface layer.

[0012] Preferably, the height of the combined expansion ring resonant cavity accounts for 3 / 4 of the height of the mixed cavity layer, and the height of the cuboid cavity accounts for 1 / 4 of the height of the mixed cavity layer.

[0013] Preferably, the perforation rate of the open-cell aluminum foam is 75-85%.

[0014] Preferably, the surface layer is made of rubber material matched with the characteristic impedance of seawater, and the bottom layer is made of rubber material matched with the characteristic impedance of the shell material of the underwater vehicle.

[0015] Preferably, the mixed cavity layer is made of polyurethane rubber.

[0016] The surface layer is made of rubber material matched with the characteristic impedance of seawater, and the bottom layer is made of rubber material matched with the characteristic impedance of the shell material of the underwater vehicle. The characteristic impedance is the ρc value, ρ represents the medium density, and c represents the medium sound speed. The closer the ρc value of the rubber material to the ρc value of seawater or the shell, the stronger the ability of the sound wave to penetrate the rubber material, and the stronger the ability to absorb the incident sound wave, which can effectively reduce the intensity of the reflected sound wave.

[0017] The mixed cavity layer is made of polyurethane rubber, which has excellent damping performance. When sound waves propagate in the material, friction occurs between the internal molecular chains due to the viscosity, and this friction converts part of the sound energy into internal energy and consumes it, which is the viscous absorption of the polyurethane material.

[0018] The combined expansion ring resonant cavity is combined by two cavities with different volumes, so that a structure system with high acoustic performance is formed, and the frequency band width of the combined expansion ring resonant cavity is widened.

[0019] The mesh structure and internal gap in the open-cell aluminum foam are beneficial to sound energy absorption, and the open-cell aluminum foam has the characteristics of low density, strong compression resistance and excellent sound absorption performance.

[0020] The novel sound-absorbing tile structure has the following beneficial effects: (1) the novel sound-absorbing tile structure adopts a combined expansion ring resonant cavity structure, and the sound-absorbing performance of the filling material filled in the cuboid cavity is excellent, so that the sound absorption performance limitation of a single sound absorption structure and the difficulty of large deformation of the sound absorption structure in a deep water high pressure environment are perfectly solved.

[0021] (2) the surface layer adopts a rubber material matched with the characteristic impedance of seawater, so that the incident sound wave can penetrate the surface layer to the maximum extent, the reflected sound wave is reduced, the detection distance of the enemy sonar is shortened, and the stealth performance of the underwater vehicle is improved; meanwhile, the bottom layer also adopts a rubber material matched with the characteristic impedance of the shell material, so that the self-noise of the underwater vehicle can penetrate the bottom layer to the maximum extent and be incident into the open-cell aluminum foam, thereby reducing the self-noise radiation.

[0022] (3) the present application is based on the principle of resonant cavity, and two cavities with different volumes are combined into a combined expansion ring resonant cavity, so that the sound absorption frequency band range can be widened.

[0023] (4) in the present application, the open-cell aluminum foam is filled in the cuboid cavity, so that the sound absorption frequency band can be expanded to low frequency, the sound absorption frequency band range is widened, and the open-cell aluminum foam can support the combined expansion ring resonant cavity, so that the deformation amount of the combined expansion ring resonant cavity can be reduced in deep sea conditions, and the performance of the sound-absorbing tile is more stable. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a sectional view of the present application.

[0025] Figure 2 is a top view of the present application.

[0026] Figure 3 is a structural schematic diagram of the present application.

[0027] Figure 4 is the sound absorption coefficient of a filled sound absorption material compression-resistant wide-band sound absorbing tile of the present application at 1k-10k frequency.

[0028] Figure 5 is the sound insulation quantity of a filled sound absorption material compression-resistant wide-band sound absorbing tile of the present application at 1k-10k frequency.

[0029] In the figure: 1: surface layer; 2: mixed cavity layer; 3: bottom layer; 4: combined expanding ring-shaped resonant cavity; 5: cuboid cavity; 6: open-cell aluminum foam; 7: cavity ring; 7-1: cavity ring A; 7-2: cavity ring B; 7-3: cavity ring C; 8: upper cavity of combined expanding ring-shaped resonant cavity; 9: lower cavity of combined expanding ring-shaped resonant cavity. DETAILED DESCRIPTION

[0030] The specific embodiments of the present application are further described below in conjunction with the accompanying drawings.

[0031] Example 1

[0032] A filled sound absorption material compression-resistant wide-band sound absorbing tile comprises a surface layer 1, a mixed cavity layer 2 and a bottom layer 3, the surface layer 1 is in contact with water, the bottom layer 3 is in contact with the surface of an underwater vehicle, the mixed cavity layer 2 is between the surface layer 1 and the bottom layer 3, a cuboid cavity 5 and a combined expanding ring-shaped resonant cavity 4 are sequentially arranged on the side of the mixed cavity layer 2 close to the bottom layer 3, one cuboid cavity 5 corresponds to several combined expanding ring-shaped resonant cavities 4, and the cuboid cavity 5 is filled with open-cell aluminum foam 6.

[0033] The height of the surface layer 1 and the bottom layer 3 is 4-6mm, and the thickness of the mixed cavity layer 2 is 8 times the height of the surface layer 1. The surface layer 1 is made of rubber material matching the characteristic impedance of seawater, and the bottom layer 3 is made of rubber material matching the characteristic impedance of the shell material of the underwater vehicle. The mixed cavity layer 2 is made of polyurethane rubber.

[0034] To ensure that the deformation does not affect each other's structure, the interval between the lower cavities 9 of two adjacent combined expanding ring-shaped resonant cavities is 1-1.5mm.

[0035] The combined expansion ring resonant cavity 4 comprises a cavity ring 7, a combined expansion ring resonant cavity upper layer cavity 8, and a combined expansion ring resonant cavity lower layer cavity 9. The cavity ring 7 comprises a cavity ring A 7-1, a cavity ring B 7-2, and a cavity ring C 7-3. The cavity ring A 7-1 is connected in sequence to the combined expansion ring resonant cavity upper layer cavity 8, the cavity ring B 7-2, the combined expansion ring resonant cavity lower layer cavity 9, and the cavity ring C 7-3. The cavity ring A 7-1, the cavity ring B 7-2, and the cavity ring C 7-3 are at the same center and have the same structure. The cavity ring height and the cavity body height are evenly distributed. The radius of the cavity ring 7 is 1.5-2 mm. The radius of the combined expansion ring resonant cavity upper layer cavity 8 is 2-2.5 times the radius of the cavity ring 7. The radius of the combined expansion ring resonant cavity lower layer cavity 9 is 2.5-4 times the radius of the cavity ring 7.

[0036] The height of the combined expansion ring resonant cavity 4 accounts for 3 / 4 of the height of the mixed cavity layer 2. The height of the cuboid cavity 5 accounts for 1 / 4 of the height of the mixed cavity layer 2.

[0037] The perforation rate of the open-cell aluminum foam 6 is 75-85%.

[0038] Example 2

[0039] A compression-resistant broadband sound-absorbing tile filled with sound-absorbing material comprises a surface layer 1, a mixed cavity layer 2, and a bottom layer 3. The surface layer 1 is in contact with water, the bottom layer 3 is in contact with the surface of a submerged vehicle, and the mixed cavity layer 2 is between the surface layer 1 and the bottom layer 3. The mixed cavity layer 2 comprises a combined expansion ring resonant cavity 4 and a cuboid cavity 5, and the cuboid cavity 5 is filled with open-cell aluminum foam 6.

[0040] The surface layer 1 is made of natural rubber material, with a density ρ = 1.003 × 10 3 kg / m 3 , a sound speed c = 1510 m / s, and a sound attenuation constant α l <0.05 dB / cm. The height of the surface layer 1 is 5 mm. The bottom layer 3 is made of chloroprene rubber, with a density ρ = 1.080 × 10 3 kg / m 3 , a sound speed c = 1510 m / s, and a sound attenuation constant α l = 0.05 dB / cm. The height of the bottom layer 3 is 5 mm. The mixed cavity layer 2 is made of polyurethane rubber, with a height of 40 mm, a density ρ = 1.080 × 10 3 kg / m 3 , a sound speed c = 1520 m / s, and a sound attenuation constant α l= 0.1 dB / cm. The height of the combined expanding ring resonant cavity 4 is 30 mm, the combined expanding ring resonant cavity 4 has 4 groups, the cavity ring 7 has a radius of 2 mm, the upper cavity 8 of the combined expanding ring resonant cavity has a radius of 5 mm, the lower cavity 9 of the combined expanding ring resonant cavity has a radius of 8 mm, and the cavity ring and the cavity have a height of 6 mm. The height of the cuboid cavity is 10 mm, the length and width are each 34 mm, the perforation rate of the perforated aluminum foam is 80%, and the height of the sound absorbing tile is 50 mm. Figure 4 and Figure 5 The sound absorption coefficient and the sound insulation amount of the filled sound absorption material compression type wide frequency band sound absorbing tile at 1k-10k frequency are shown in the figure, and it can be seen that the sound absorption coefficient at 1.5k frequency is close to 1, reaching almost perfect sound absorption effect, the sound absorption coefficient in the whole frequency range is also higher than 0.5, and the sound insulation amount at high frequency is also higher than 90dB, showing good sound absorption effect, which shows that the filled sound absorption material compression type wide frequency band sound absorbing tile has excellent acoustic performance.

[0041] The above specific embodiments further illustrate the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A pressure-resistant broadband sound-absorbing tile filled with sound-absorbing material, characterized in that: It includes a surface layer (1), a mixed cavity layer (2) and a bottom layer (3). The surface layer (1) is in contact with water, and the bottom layer (3) is in contact with the surface of the underwater vehicle. The mixed cavity layer (2) is located between the surface layer (1) and the bottom layer (3). The mixed cavity layer (2) has a cuboid cavity (5) and N sets of combined expansion annular resonant cavities (4) arranged sequentially on the side near the bottom layer (3), where N ≥ 1. The cuboid cavity (5) is filled with open-cell aluminum foam (6), and the N sets of combined expansion annular resonant cavities (4) are connected to the cuboid cavity (5). The combined expanded annular resonant cavity (4) includes a cavity ring (7), an upper cavity of the combined expanded annular resonant cavity (8), and a lower cavity of the combined expanded annular resonant cavity (9); the cavity ring (7) includes a cavity ring A (7-1), a cavity ring B (7-2), and a cavity ring C (7-3), and the cavity ring A (7-1) is connected in sequence to the upper cavity of the combined expanded annular resonant cavity (8), the cavity ring B (7-2), the lower cavity of the combined expanded annular resonant cavity (9), and the cavity ring C (7-3).

2. The pressure-resistant broadband sound-absorbing tile filled with sound-absorbing material according to claim 1, characterized in that, The radius of the cavity ring (7) is 1.5~2mm; the radius of the upper cavity (8) of the combined expanded annular resonant cavity is 2~2.5 times the radius of the cavity ring (7); the radius of the lower cavity (9) of the combined expanded annular resonant cavity is 2.5~4 times the radius of the cavity ring (7).

3. The pressure-resistant broadband sound-absorbing tile filled with sound-absorbing material according to claim 1, characterized in that, The interval between the lower cavity (9) of the two adjacent sets of combined expanded annular resonant cavities is 1~1.5mm.

4. The pressure-resistant broadband sound-absorbing tile filled with sound-absorbing material according to claim 1, characterized in that, The height of the surface layer (1) and the bottom layer (3) is 4~6mm.

5. The pressure-resistant broadband sound-absorbing tile filled with sound-absorbing material according to claim 1, characterized in that, The height of the hybrid cavity layer (2) is 8 times the height of the surface layer (1).

6. The pressure-resistant broadband sound-absorbing tile filled with sound-absorbing material according to claim 1, characterized in that, The height of the combined expanded annular resonant cavity (4) accounts for 3 / 4 of the height of the mixed cavity layer (2), and the height of the cuboid cavity (5) accounts for 1 / 4 of the height of the mixed cavity layer (2).

7. The pressure-resistant broadband sound-absorbing tile filled with sound-absorbing material according to claim 1, characterized in that, The perforation rate of the open-cell aluminum foam (6) is 75-85%.

8. The pressure-resistant broadband sound-absorbing tile filled with sound-absorbing material according to claim 1, characterized in that, The outer layer (1) is made of rubber material that matches the characteristic impedance of seawater, and the inner layer (3) is made of rubber material that matches the characteristic impedance of the underwater submersible shell material.

9. The pressure-resistant broadband sound-absorbing tile filled with sound-absorbing material according to claim 1, characterized in that, The hybrid cavity layer (2) is made of polyurethane rubber.

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