CN110565826A - A composite sound-absorbing structure for low-frequency noise reduction - Google Patents

Abstract

A composite sound-absorbing structure for low-frequency noise reduction, comprising an aluminum fiber board (1), a polyester fiber board (2), and an air layer (3). The aluminum fiber board and the polyester fiber board are connected by adhesive, rivets or screws; the arrangement sequence of the composite sound-absorbing structure is from the direction of the sound source, followed by the aluminum fiber board, the polyester fiber board, and the air layer. The air layer is a resonant cavity with a certain thickness of air layer formed by connecting the polyester fiberboard and the aluminum alloy bottom plate through the dragon frame. Compared with the prior art, the low-frequency noise-reducing composite sound-absorbing structure of the present invention has excellent sound-absorbing performance, light weight, small space occupation, environmental protection, low cost, and convenient installation, especially in the low-frequency part of 100-500Hz. The coefficients are all greater than 0.6, which is greatly improved compared with traditional sound-absorbing structures or materials, and is very suitable for various places that require deep noise reduction for low-frequency noise.

Description

A composite sound-absorbing structure for low-frequency noise reduction

technical field

The invention relates to a composite sound-absorbing structure for low-frequency noise reduction, which belongs to the technical field of low-frequency noise reduction.

Background technique

With the improvement of people's living standards, people's requirements for the comfort of the living environment are getting higher and higher, and the control of noise pollution in the low frequency band has always been a difficult problem for us. Traditional sound-absorbing materials have obvious sound absorption in the low-frequency stage. trough.

CN204753867U discloses a low-frequency sound-absorbing panel. This patent uses fiberboard as a substrate, and uses hot-melt omentum as an adhesive to compound veneer on the fiberboard to obtain a low-frequency sound-absorbing panel. Although it is environmentally friendly and non-toxic, its absorption effect for low-frequency noise is improved. It is still limited, so the low-frequency sound absorption valley cannot be significantly improved in actual use.

Contents of the invention

The object of the present invention is to provide a composite sound-absorbing structure for low-frequency noise reduction, aiming at the problems existing in the existing low-frequency sound-absorbing panels.

The technical solution realized by the present invention is as follows, a composite sound-absorbing structure for low-frequency noise reduction, including aluminum fiber boards, polyester fiber boards and an air layer; the aluminum fiber boards and polyester fiber boards are connected by adhesives, rivets or screws; The arrangement order of the composite sound-absorbing structure is from the direction of the sound source, which is aluminum fiber board, polyester fiber board and air layer.

The aluminum fiber board and the polyester fiber board are rectangular plate structures with the same area.

The thickness of the aluminum fiberboard is 1.5-2.5mm, and the surface density is 1600-3200g/m ² .

The polyester fiber board is made of special-shaped polyester fibers with a flat fiber cross section; the thickness of the polyester fiber board is 10-30 mm; the density of the polyester fiber board is 150-200 kg/m ³ .

The air layer is a resonant cavity with a certain thickness of air layer formed by connecting the polyester fiber board and the aluminum alloy bottom plate through the keel; the thickness of the air layer is not less than 100mm.

The working principle of the present invention is as follows. The composite sound-absorbing structure of the present invention is composed of aluminum fiber board, polyester fiber board and air layer. Compared with ordinary polyester fibers, special-shaped polyester fibers with flat cross-section have larger fiber cross-sections and more fine pores. After the sound wave enters the material, there are more opportunities for friction between the fiber interface and the pores, and the sound energy dissipation increases. The sound absorption performance is improved; the resonance cavity of a certain thickness of air layer is formed between the polyester fiberboard and the bottom plate through the connection of the keel, which can significantly improve the low-frequency sound absorption coefficient; the aluminum fiberboard greatly increases the acoustic impedance, making the low-frequency noise reduction performance better.

The beneficial effect of the present invention is that, compared with the prior art, the low-frequency noise-reducing composite sound-absorbing structure of the present invention is thinner, lighter in weight, and convenient in construction; It has excellent mechanical properties; the overall structure has excellent sound absorption performance, light weight, small space occupation, environmental protection, low cost, and easy installation. Especially in the low frequency part of 100-500Hz, the average sound absorption coefficient is greater than 0.6, which is higher than traditional sound absorption. The structure or material has been greatly improved, and it is very suitable for various places that require deep noise reduction for low-frequency noise.

Description of drawings

Fig. 1 is a schematic diagram of a composite sound-absorbing structure for low-frequency noise reduction of the present invention;

Fig. 2 is a schematic diagram of the arrangement sequence of the composite sound-absorbing structure for low-frequency noise reduction of the present invention;

In the figure, 1 is an aluminum fiber board; 2 is a polyester fiber board; 3 is an air layer; 4 is a frame of a structural part; 5 is a bottom plate.

Detailed ways

As shown in FIG. 1 , the present invention will be described in detail below in conjunction with specific embodiments.

Example 1

In this example, the aluminum fiberboard is connected with the 10mm polyester fiberboard. Under the condition of superimposing a 100mm air layer, the finished product is tested for the sound absorption coefficient through the impedance tube, and it is found that the average value of the sound absorption coefficient between 100-500Hz reaches 0.6238 , the specific sound absorption coefficient at each center frequency is shown in the table below.

Frequency (Hz) 100 125 160 200 250 315 400 500 Abs 0.33 0.4 0.51 0.6 0.68 0.73 0.75 0.99

Example 2

In this example, the aluminum fiberboard is connected to the 16mm polyester fiberboard, and under the condition of superimposing a 100mm air layer, the finished product is tested for the sound absorption coefficient through the impedance tube, and it is found that the average value of the sound absorption coefficient between 100-500Hz reaches 0.6575, The specific sound absorption coefficient at each center frequency is shown in the table below.

Frequency (Hz) 100 125 160 200 250 315 400 500 Abs 0.26 0.39 0.69 0.79 0.81 0.8 0.77 0.75

Example 3

In this embodiment, the aluminum fiberboard is connected with the 12mm polyester fiberboard. Under the condition of superimposing a 200mm air layer, the finished product is tested for the sound absorption coefficient through the impedance tube, and it is found that the average value of the sound absorption coefficient between 100-500Hz reaches 0.7413. The specific sound absorption coefficient at each center frequency is shown in the table below.

Frequency (Hz) 100 125 160 200 250 315 400 500 Abs 0.57 0.65 0.72 0.77 0.8 0.81 0.8 0.81

Example 4

In this embodiment, the aluminum fiberboard is connected with the 28mm polyester fiberboard. Under the condition of superimposing a 300mm air layer, the finished product is passed through the impedance tube to test the sound absorption coefficient. It is found that the average value of the sound absorption coefficient between 100-500Hz reaches 0.775. The specific sound absorption coefficient at each center frequency is shown in the table below.

Frequency (Hz) 100 125 160 200 250 315 400 500 Abs 0.47 0.91 0.96 0.95 0.89 0.83 0.72 0.47

The compound sound-absorbing structure for low-frequency noise reduction of the present invention has excellent performance, light weight, small space occupation, convenient installation and low environmental protection cost, especially in the low-frequency part of 100-500Hz, the average value of the sound absorption coefficient is greater than 0.6, which is better than traditional sound-absorbing materials. Greatly improved, it is very suitable for all kinds of places that require deep noise reduction for low-frequency noise.

Claims (5)

1. A composite sound-absorbing structure for low-frequency noise reduction, characterized in that, the composite sound-absorbing structure includes aluminum fiber boards, polyester fiber boards, and an air layer; the aluminum fiber board and the polyester fiber board are passed through adhesives, rivets or Screw connection; the arrangement order of the composite sound-absorbing structure is from the direction of the sound source, followed by aluminum fiber board, polyester fiber board, and air layer. 2 . The composite sound-absorbing structure for low-frequency noise reduction according to claim 1 , wherein the thickness of the aluminum fiber board is 1.5-2.5 mm, and the surface density is 1600-3200 g/m ² . 3 . The composite sound-absorbing structure for low-frequency noise reduction according to claim 1 , wherein the polyester fiber board is made of special-shaped polyester fiber with a flat fiber cross section. 4 . 4 . The composite sound-absorbing structure for low-frequency noise reduction according to claim 1 , wherein the thickness of the polyester fiber board is 10-30 mm; the density of the polyester fiber board is 150-200 kg/m ³ . 5. A composite sound-absorbing structure for low-frequency noise reduction according to claim 1, wherein the air layer is formed by connecting the polyester fiber board and the aluminum alloy base plate through a keel frame to form a resonance of a certain thickness of the air layer Cavity; the thickness of the air layer is not less than 100mm.