Wideband sound barrier based on variable curve boundary cellular resonant cavity

Abstract

The invention provides a broadband sound barrier based on a variable curve boundary honeycomb type resonant cavity. The broadband sound barrier comprises a plurality of variable curve boundary honeycomb type resonant cavity sound absorption structure cells and a supporting and connecting assembly. The plurality of cells are connected together through the supporting and connecting assembly to form an arc-shaped sound barrier; each cell is a hollow cylindrical shell with a regular hexagonal cross section; the centers of the two end faces of each cell are vertically through, and openings in the centers of the two end faces are circles with different sizes; openings in the centers of the two end surfaces are in smooth transition to form inner side surfaces of the cells; a plurality of partition plates perpendicular to the height direction are arranged in the cells in the vertical height direction, and the partition plates divide the interiors of the cells into a plurality of Helmholtz resonant cavities with the same height or different heights. The traffic sound barrier has the advantages that the traffic sound barrier has the broadband sound absorption characteristic, and the defect that a traditional closed traffic sound barrier is narrow in sound absorption frequency band is overcome; certain ventilation and lighting performance is achieved, and the driving environment of an inner channel of the closed traffic sound barrier can be more comfortable.

Description

Technical Field

[0001] This application belongs to the field of traffic noise reduction, specifically relating to a broadband sound barrier based on a honeycomb resonant cavity with variable curved boundaries. Background Technology

[0002] With the rapid development of my country's highway and railway network construction, and the rapid growth of urban roads and traffic flow, traffic noise is becoming increasingly harmful, and environmental noise pollution is becoming more and more serious, which has become a major public hazard that pollutes the human social environment.

[0003] Sound barriers are widely used as an effective means of controlling road traffic noise pollution. Noise reaches the receiving point through three paths: diffraction, transmission, and reflection. Top diffraction is the most prevalent path; aside from a small portion of sound waves reaching the receiving point through transmission and multiple reflections, most sound waves diffract through the top of the sound barrier. A high-performance sound barrier needs to attenuate top diffracted sound sufficiently to achieve good noise reduction. However, traditional sound barriers are not designed with broadband noise absorption adjustments tailored to specific noise environments, using identical barriers in all noise conditions. This results in insufficient noise reduction performance in some environments. Furthermore, the increased top structure of traditional sound barriers increases their overall height, reducing light transmittance and affecting visibility under natural light conditions, indirectly increasing the risk of accidents at high speeds.

[0004] In summary, traditional sound barriers cannot meet the needs of environmental noise control, especially for high-speed railway noise. Therefore, the research and development of advanced, effective, and innovative next-generation sound barriers is urgently needed. Acoustic metamaterials have seen rapid development in recent years, demonstrating absolute advantages in sound wave manipulation due to their unique subwavelength dimensions and functional characteristics, such as anomalous refraction and reflection, acoustic holography, and compact, perfect sound absorbers. The emergence of acoustic metamaterials in recent years has also provided new possibilities for the fabrication of ventilated sound barriers, achieving low-frequency noise control at the subwavelength scale using local resonant units (such as Helmholtz resonators and thin films). However, metamaterials generally used for sound insulation only focus on the internal path design of sound waves, achieving only narrowband sound insulation. Current research has employed the method of multiple resonances using Helmholtz resonators to broaden the effective sound absorption bandwidth, but this still limits the bandwidth or reduces the ventilation effect to some extent.

[0005] Furthermore, the road noise barriers in actual use are mainly "vertical" types, which have insufficient diffraction attenuation. To improve this shortcoming, a common method is to add a top structure to the "vertical" noise barrier. However, adding a top structure to traditional noise barriers increases the overall height of the barrier, thereby reducing its light transmittance; traditional enclosed noise barriers can lead to increased internal temperature and reverberation, while also affecting visibility under natural light conditions. In addition, to ensure ventilation and air exchange inside the noise barrier, an additional ventilation system must be installed, directly increasing the budget. Therefore, improvements to traditional enclosed noise barriers are necessary. Summary of the Invention

[0006] The purpose of this application is to overcome the shortcomings of existing sound barriers in terms of broadband sound absorption, ventilation, and light transmission.

[0007] To achieve the above objectives, this application proposes a broadband sound barrier based on a variable curved boundary honeycomb resonant cavity, the sound barrier comprising: Multiple variable-curve boundary honeycomb resonant cavity sound-absorbing structural cells and supporting connection components; The supporting connection component connects multiple variable curved boundary honeycomb resonant cavity sound-absorbing structure cells together to form an arc-shaped sound barrier. The variable curved boundary honeycomb resonant cavity sound-absorbing structure cell is a hollow columnar shell with a regular hexagonal cross-section; the two end faces of the variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell are connected vertically, and the openings at the center of the two end faces are circles of different sizes; the openings at the center of the two end faces smoothly transition to form the inner surface of the variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell. The variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell has several partitions perpendicular to the height direction along the vertical height, dividing its interior into multiple Helmholtz resonant cavities with the same or different heights.

[0008] As an improvement to the aforementioned sound barrier, the Helmholtz resonant cavity has an annular opening on the inner surface of the sound-absorbing structural cell of the variable curved boundary honeycomb resonant cavity.

[0009] As an improvement to the aforementioned sound barrier, the annular opening of the Helmholtz resonant cavity extends inward into a flat, plate-shaped neck of a predetermined depth.

[0010] As an improvement to the aforementioned sound barrier, the outer surface of the sound-absorbing structural cell of the variable curved boundary honeycomb resonant cavity is a shell of uniform thickness.

[0011] As an improvement to the aforementioned sound barrier, the inner surface of the sound-absorbing structural cell of the variable curved boundary honeycomb resonant cavity is a curved surface of uniform thickness.

[0012] As an improvement to the aforementioned sound barrier, the shell material of the variable curved boundary honeycomb resonant cavity sound-absorbing structure cell is aluminum alloy.

[0013] As an improvement to the aforementioned sound barrier, the partition material of the variable curved boundary honeycomb resonant cavity sound-absorbing structure cell is plastic or other sound-absorbing material.

[0014] As an improvement to the aforementioned sound barrier, the supporting connection component is made of cast iron or stainless steel.

[0015] Compared with existing technologies, the advantages of this application are: 1. The broadband sound barrier based on a variable curved boundary honeycomb resonant cavity provided by the present invention has wide frequency sound absorption characteristics, which makes up for the shortcomings of the narrow sound absorption frequency band of traditional enclosed traffic sound barriers.

[0016] 2. Since the sound-absorbing structural cells in this invention are centrally connected, they also have certain ventilation and lighting properties, which can make the driving environment inside the enclosed traffic sound barrier more comfortable. Attached Figure Description

[0017] Figure 1 The diagram shows the smallest installation unit structure formed by connecting the sound-absorbing structural cells and the supporting connection components, as well as the overall structure diagram of the sound barrier. Figure 2 The diagram shows a three-dimensional view and a longitudinal cross-sectional view of a broadband sound-absorbing structure cell based on a honeycomb resonant cavity with variable curved boundaries. Figure 3 The diagram shows a top view and a longitudinal cross-sectional view of a broadband sound-absorbing structure cell based on a honeycomb resonant cavity with variable curved boundaries. Figure 4 The diagram shown illustrates the calculation of Helmholtz resonant cavity parameters.

[0018] Attached image labels: 1. Supporting connection components; 2. Variable curved boundary honeycomb resonant cavity sound-absorbing structure cells. 201. Partition; 202. Neck 203. Helmholtz resonator Detailed Implementation

[0019] The technical solution of this application will be described in detail below with reference to the accompanying drawings.

[0020] To address the shortcomings of existing sound barriers in terms of broadband sound absorption, ventilation, and light transmission, such as... Figure 1As shown, the present invention provides a broadband sound barrier structure based on a variable curved boundary honeycomb resonant cavity, which may include a variable curved boundary honeycomb resonant cavity sound-absorbing structural cell 2 and a support connection assembly 1. The variable curved boundary honeycomb resonant cavity broadband sound-absorbing structural cell 2 can be assembled into a whole by the support connection assembly 1, and the support connection is sealed.

[0021] like Figure 2 and Figure 3 As shown, the variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell 2 can be a hollow cylindrical shell with a regular hexagonal cross-section. The two end faces of the variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell 2 can be vertically connected, and the central openings of the two end faces can be circles of different sizes. The inner surface of the variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell 2 can be a smooth transition between the central openings of the two end faces. The outer surface of the variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell 2 can be a shell with a uniform thickness. Inside the variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell 2, four partitions 201 perpendicular to the height direction can be present along the vertical height, dividing the interior into five Helmholtz resonant cavities 203 with the same or different heights. Each Helmholtz resonant cavity 203 has a different volume. The inner surface of the Helmholtz resonant cavity 203 can be a curved, uniformly thick structure as its boundary. Each Helmholtz resonator 203 may have an annular opening on its inner surface, and a flat, plate-shaped neck 202 of a certain depth may extend from the opening into the Helmholtz resonator 203. These Helmholtz resonators 203 with different volumes ensure that the sound barrier has a wide frequency response, and the overall sound absorption frequency band can be adjusted by changing the parameters of the variable curve, the number of partitions 201, or the spacing between partitions 201. The curve may be an inverse proportional function or a logarithmic curve, etc.

[0022] like Figure 4 As shown, the resonant frequency is known. With resonant cavity volume The relationship is , The speed of sound is constant at 340 m / s. L is the shell thickness, and V is the volume of the resonant cavity, which can be calculated using an integral formula (here, the volume from a to b is calculated). The parameters of the resonant cavity can be calculated using the required resonant frequency.

[0023] In terms of sound absorption, this application utilizes a Helmholtz resonant cavity. When sound waves propagate into resonant cavities of different volumes, a resonance effect is generated, reducing the sound pressure level and thus mitigating noise pollution from vehicles and trains. Simultaneously, the sound barrier is connected at both ends, combining the advantages of ventilation and lighting to comprehensively optimize the driving experience within the sound barrier. This sound barrier can optimize its ventilation and sound absorption performance by changing the size and thickness of the honeycomb units and altering the volume of the resonant cavity. In short, this barrier organically combines the concepts of sound barriers, light barriers, and wind barriers, possessing advantages of high efficiency, rational design, simplicity, convenience, novelty, and aesthetics. It is suitable for noise control in high-speed rail viaducts, highways, urban light rail, subways, etc., and is suitable for widespread application with significant economic benefits.

[0024] In a preferred embodiment of the present invention, the shell material of the variable curved boundary honeycomb resonant cavity broadband sound-absorbing structural cell 2 is aluminum alloy and its products, the partition 201 is plastic or other sound-absorbing material, and the material of the supporting connection component 1 can be cast iron or stainless steel and its products.

[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of this application do not depart from the spirit and scope of the technical solutions of this application, and should all be covered within the scope of the claims of this application.

Claims

1. A broadband sound barrier based on a honeycomb resonant cavity with variable curved boundaries, characterized in that, The sound barrier includes: Multiple variable-curve boundary honeycomb resonant cavity sound-absorbing structural cells and supporting connection components; The supporting connection component connects multiple variable curved boundary honeycomb resonant cavity sound-absorbing structure cells together to form an arc-shaped sound barrier. The variable curved boundary honeycomb resonant cavity sound-absorbing structure cell is a hollow columnar shell with a regular hexagonal cross-section; the two end faces of the variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell are connected vertically, and the openings at the center of the two end faces are circles of different sizes; the openings at the center of the two end faces smoothly transition to form the inner surface of the variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell. The variable curved boundary honeycomb resonant cavity broadband sound-absorbing structure cell has several partitions perpendicular to the height direction along the vertical height, dividing its interior into multiple Helmholtz resonant cavities with the same or different heights.

2. The broadband sound barrier based on a variable curved boundary honeycomb resonant cavity according to claim 1, characterized in that, The Helmholtz resonant cavity has an annular opening on the inner surface of the sound-absorbing structural cell of the honeycomb resonant cavity with variable curved boundary.

3. The broadband sound barrier based on a variable curved boundary honeycomb resonant cavity according to claim 2, characterized in that, The annular opening of the Helmholtz resonant cavity extends inward to form a flat, plate-shaped neck of a predetermined depth.

4. The broadband sound barrier based on a variable curve boundary honeycomb resonant cavity according to claim 1, characterized in that, The outer surface of the sound-absorbing structure cell of the variable curved boundary honeycomb resonant cavity is a shell of equal thickness.

5. The broadband sound barrier based on a variable curved boundary honeycomb resonant cavity according to claim 1, characterized in that, The inner surface of the sound-absorbing structure cell of the variable curved boundary honeycomb resonant cavity is a curved surface of uniform thickness.

6. The broadband sound barrier based on a variable curved boundary honeycomb resonant cavity according to claim 1, characterized in that, The shell material of the sound-absorbing structure cell of the variable curved boundary honeycomb resonant cavity is aluminum alloy.

7. The broadband sound barrier based on a variable curved boundary honeycomb resonant cavity according to claim 1, characterized in that, The partition material of the sound-absorbing structural cell of the variable curved boundary honeycomb resonant cavity is plastic or other sound-absorbing material.

8. The broadband sound barrier based on a variable curved boundary honeycomb resonant cavity according to claim 1, characterized in that, The supporting connection component is made of cast iron or stainless steel.

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