Straight neck slit type natural ventilation sound insulator

Abstract

The invention discloses a straight-neck slit type natural ventilation sound insulator, which belongs to the field of ventilation and sound insulation, and comprises a plurality of groups of Helmholtz resonant cavity type acoustic metamaterial unit cell structures which are arranged according to a parallel connection or rotation rule, wherein the acoustic metamaterial unit cell structure is a three-dimensional structure and comprises a cylindrical hollow pipeline for air circulation, a long and narrow air channel and a Helmholtz sound absorption resonator; the adjacent acoustic metamaterial unit cell structures are connected through a connecting wall, and the adjacent acoustic metamaterial unit cell structures have a common cylindrical hollow pipeline. Depending on the unique geometric structure permutation and combination, the sound wave can generate resonance coupling with the resonators arranged and distributed on the two sides when being transmitted to the air channel, so that the sound energy transmission is reduced; meanwhile, the long and narrow air channels can enable sound waves and the structure to generate extra thermal viscosity loss, and sound wave energy loss is intensified; and the diameter of the pipeline is large, so that excellent natural ventilation quantity can be ensured.

Description

Technical Field

[0001] The invention relates to the field of ventilation and sound insulation, in particular to a straight-necked slit-type natural ventilation sound insulator. Background Art

[0002] For residential buildings, there are two main ways for noise to propagate through enclosures: airborne sound transmission and solid-body sound transmission. Airborne sound transmission refers to the transmission of noise sources through air as a medium, and sound energy is transmitted to another space through enclosures. Typical airborne sound transmission includes traffic noise and living noise transmitted into the room through weak links such as windows and doors. Therefore, it is necessary to control the propagation path of sound waves, namely airborne sound transmission, including isolation, attenuation and absorption. With the continuous advancement of science and technology and the continuous development of industry, product structure and performance are becoming more and more optimized, and it has become increasingly difficult to control noise from the source. In this way, controlling the propagation path has become an inevitable choice.

[0003] Most measures taken by residential buildings to deal with noise problems today are to install double-layer glass or even triple-layer glass in indoor buildings, which greatly alleviates the problem of air noise transmission, but faces the problem of "no ventilation when windows are closed, no sound insulation when windows are open". From the perspective of green buildings, opening windows for natural ventilation will inevitably bring noise to the interior. Sound insulation measures such as closed windows will hinder the circulation of air and make it impossible to achieve indoor and outdoor air exchange. High-quality indoor air quality is also an important demand of people for the indoor environment, which is directly related to people's physical and mental health and comfort. The fresh air system can achieve indoor and outdoor air exchange and air quality purification, but it will also generate certain noise when it is running. Therefore, natural ventilation is still the most commonly used and convenient indoor ventilation method. Therefore, it is particularly important to design a reasonable natural ventilation acoustic sound isolator in the face of indoor and outdoor air exchange and isolation of external noise. Summary of the invention

[0004] The purpose of the present invention is to provide a straight-necked slit-type natural ventilation sound insulator, which mainly relies on its unique geometric structure arrangement and combination. When the sound wave propagates to the hollow pipe, it will resonate and couple with the resonators arranged and distributed on both sides, thereby reducing the propagation of sound energy.

[0005] In order to achieve the above-mentioned invention object, the present invention adopts the following technical scheme:

[0006] The present invention provides a straight-neck slit-type natural ventilation sound insulator, comprising a plurality of groups of Helmholtz resonant cavity-type acoustic metamaterial unit cell structures arranged in parallel or in a rotational pattern; wherein:

[0007] The acoustic metamaterial unit cell structure is a three-dimensional structure, including a cylindrical hollow pipe for air circulation, a narrow air channel and a Helmholtz sound absorption resonator; the air channel is arranged perpendicular to the axial direction of the cylindrical hollow pipe, and the front end of the air channel is connected to the cylindrical hollow pipe, and the end of the air channel is connected to a rear chamber through a narrow channel, and the rear chamber is an annular chamber with the same axis as the cylindrical hollow pipe, and the Helmholtz sound absorption resonator includes the narrow channel, the rear chamber and part of the air channel;

[0008] Adjacent acoustic metamaterial unit cell structures are connected via connecting walls, and adjacent acoustic metamaterial unit cell structures have a common cylindrical hollow pipe.

[0009] Furthermore, the structure is: M acoustic metamaterial unit cell structures are connected in parallel in a two-dimensional plane where the axis is located, and the plane perpendicular to the axis direction is used as a mirror plane, the acoustic metamaterial unit cell structure is mirrored into N units, and then the unit cell structure is rotated 360° with the axis direction as the rotation center to form a cylindrical three-dimensional structure;

[0010] Wherein, both M and N are positive integers not less than 1.

[0011] Furthermore, its overall outer diameter is 152.4 mm, and the inner diameter of the cylindrical hollow pipe for air circulation is 100 mm.

[0012] Furthermore, the M is 3 and the N is 2.

[0013] Furthermore, the Helmholtz sound-absorbing resonators arranged in parallel are configured with narrow and long channels, rear chambers and air channels of different size parameters according to the frequency range of the noise value to be isolated.

[0014] Compared with the prior art, one or more of the above technical solutions have the following beneficial effects:

[0015] (1) The present invention can realize the quantitative design of different noise spectra. The characteristic of different resonators being connected in parallel can effectively isolate the noise values ​​in different frequency ranges and realize excellent sound transmission loss.

[0016] (2) The sound insulation structure designed by the present invention is usually relatively light and has excellent mechanical properties. When subjected to external pressure or impact, the overall cylindrical structure can effectively disperse stress and improve the overall strength and rigidity.

[0017] (3) The large-diameter 100mm cylindrical air circulation hollow duct designed by the present invention can effectively solve the problem of insufficient natural ventilation. There is no need to worry about insufficient ventilation and the daily natural ventilation needs of residents can be met.

[0018] (4) The acoustic metamaterial unit cell structure designed in the present invention has the advantage of good designability. Its geometric shape and material can be customized according to certain requirements, and its physical geometric parameters can be adjusted according to specific needs to achieve a reasonable and excellent sound insulation effect.

[0019] (5) The rear chamber and the narrow channel of the acoustic metamaterial unit cell structure in the present invention are connected in parallel and mirrored to form a straight-necked slit-type pipe, and the air contact between the straight-necked slit-type pipe and the air channel can effectively enhance the thermoviscous loss, so that the sound transmission loss reaches a high loss value.

[0020] (6) Based on metamaterial design technology, the process of manufacturing straight-neck slit-type sound insulation metamaterials is relatively simple and can adapt to different design requirements and production processes. The cost of raw materials is low, which makes it economical in commercial applications. It can also be combined with other functions, such as fire prevention and dehumidification, to meet complex application requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0022] Figure 1 It is a two-dimensional simplified schematic diagram of the Helmholtz sound absorbing resonator of the present invention.

[0023] Figure 2 This is one of the half-section model diagrams of the straight-necked slit-type natural ventilation sound insulator of the present invention.

[0024] Figure 3 This is the second half-section model diagram of the straight-necked slit-type natural ventilation sound insulator of the present invention.

[0025] Figure 4 It is a three-dimensional model diagram of the straight-necked slit-type natural ventilation sound insulator of the present invention.

[0026] Figure 5 This is a sound transmission loss curve of the straight-neck slit-type natural ventilation sound insulator structure in Example 1.

[0027] In the figure:

[0028] 100. Cylindrical hollow pipe, 200. Air channel, 300. Helmholtz sound absorbing resonator, 310. Narrow channel, 320. Rear chamber, 400. Connecting wall. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0030] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0031] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0032] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0033] In addition, the terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0034] Example 1

[0035] like Figure 1-Figure 4As shown, a straight-necked slit-type natural ventilation sound insulator of the present invention comprises a plurality of groups of Helmholtz resonant cavity-type acoustic metamaterial unit cell structures arranged in parallel or in rotation; wherein,

[0036] The acoustic metamaterial unit cell structure is a three-dimensional structure, including a cylindrical hollow pipe 100 for air circulation, an air channel 200 and a Helmholtz sound absorption resonator 300; the air channel 200 is arranged perpendicular to the axial direction of the cylindrical hollow pipe 100, and the front end of the air channel 200 is connected to the cylindrical hollow pipe 100, and the end of the air channel 200 is connected to a rear chamber 320 through a narrow channel 310, and the rear chamber 320 is an annular chamber with the same axis as the cylindrical hollow pipe 100, and the Helmholtz sound absorption resonator 300 includes the narrow channel 310, the rear chamber 320 and part of the air channel 200;

[0037] Adjacent acoustic metamaterial unit cell structures are connected via a connecting wall 400 , and the adjacent acoustic metamaterial unit cell structures have a common cylindrical hollow pipe 100 .

[0038] The structure of the straight-neck slit-type natural ventilation sound insulator is: M acoustic metamaterial unit cell structures are connected in parallel in a two-dimensional plane where the axis is located, and the plane perpendicular to the axis direction is used as a mirror plane, the acoustic metamaterial unit cell structure is mirrored into N units, and then the cylindrical three-dimensional structure is formed by rotating 360° with the axis direction as the rotation center;

[0039] Wherein, both M and N are positive integers not less than 1, M is preferably 3, and N is preferably 2. In this embodiment, the overall outer diameter of the straight-necked slit-type natural ventilation sound insulator is 152.4 mm, and the inner diameter of the cylindrical hollow pipe 100 for air circulation is 100 mm.

[0040] It is worth noting that the parallel-arranged Helmholtz sound-absorbing resonators are configured with narrow channels 310, rear chambers 320 and air channels 200 of different size parameters according to the frequency range of the noise value to be isolated. The aforementioned size parameters, for example Figure 1 A, B, C, D, E, W shown can be customized for specific frequency ranges.

[0041] The parallel Helmholtz sound absorbing resonators of the present invention are composed of different size parameters and have the characteristic that the size parameters can be freely designed, such as Figure 1As shown, when the sound wave is incident from the left side of the cylindrical hollow pipe 100 and propagates into the pipe, a considerable part of the sound wave will enter the narrow air channel 200 through the straight neck slit, and then propagate into the Helmholtz resonator. The geometric shape of the resonator can couple and resonate with the sound wave, resulting in a large amount of sound energy being dissipated, causing the sound pressure value of the sound wave to decrease.

[0042] At the same time, when entering the straight neck slit (narrow channel 310), the sound wave will experience thermoviscous loss to a certain extent, thereby weakening the energy of the sound wave, further reducing the sound pressure value and enhancing the sound insulation effect. Among them, the air cavity in the resonator will interact with the sound wave to convert the sound energy into heat energy. Sound-absorbing resonators of different parameter sizes have natural frequencies corresponding to sound waves. By coupling different resonators in parallel, the sound transmission loss under a specific spectrum can be achieved, which has the advantage of flexible designability.

[0043] See attached Figure 5 As shown in the figure, the straight neck slit type sound insulator is numerically simulated using finite element software. It can be seen that the average sound transmission loss in the 740Hz-1030Hz frequency domain is greater than 10Db. In particular, the TL values ​​near 865Hz, 970Hz, and 1150Hz reach 43dB, 45dB, and 43dB respectively. This shows that in actual specific applications, the expected noise reduction range can be achieved by simply designing the structural parameters and dimensions of a single resonator and combining them in parallel for the corresponding noise spectrum range.

[0044] In order to meet the actual needs of engineering, the structural parameter dimensions of a single resonator are simply designed and combined in parallel according to the corresponding noise spectrum range to achieve the expected noise reduction range. In this way, a straight-necked slit-type acoustic metamaterial with good ventilation and sound insulation performance is designed.

[0045] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A straight neck slit type natural ventilation sound insulator, characterized in that: It includes several groups of Helmholtz resonant cavity acoustic metamaterial unit cell structures arranged in parallel or in rotation; wherein, The acoustic metamaterial unit cell structure is a three-dimensional structure, including a cylindrical hollow pipe for air circulation, a narrow air channel and a Helmholtz sound absorption resonator; the air channel is arranged perpendicular to the axial direction of the cylindrical hollow pipe, and the front end of the air channel is connected to the cylindrical hollow pipe, and the end of the air channel is connected to a rear chamber through a narrow channel, and the rear chamber is an annular chamber with the same axis as the cylindrical hollow pipe, and the Helmholtz sound absorption resonator includes the narrow channel, the rear chamber and part of the air channel; Adjacent acoustic metamaterial unit cell structures are connected via connecting walls, and adjacent acoustic metamaterial unit cell structures have a common cylindrical hollow pipe.

2. The straight-necked slit-type natural ventilation sound insulator according to claim 1, characterized in that: Its structure is: M acoustic metamaterial unit cell structures are connected in parallel in a two-dimensional plane where the axis is located, and the plane perpendicular to the axis direction is used as a mirror plane, the acoustic metamaterial unit cell structure is mirrored into N units, and then the cylindrical three-dimensional structure is formed by rotating 360 degrees with the axis direction as the rotation center; Wherein, both M and N are positive integers not less than 1.

3. The straight-necked slit-type natural ventilation sound insulator according to claim 1, characterized in that: Its overall outer diameter is 152.4mm, and the inner diameter of the cylindrical hollow pipe for air circulation is 100mm.

4. The straight-necked slit-type natural ventilation sound insulator according to claim 2, characterized in that: The M is 3, and the N is 2.

5. The straight-necked slit-type natural ventilation sound insulator according to claim 4, characterized in that: The Helmholtz sound-absorbing resonators arranged in parallel are configured with narrow and long channels, rear chambers and air channels of different size parameters according to the frequency range of the noise value to be isolated.

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