Resonance unit of a ventilated ultra-wideband low-frequency sound insulation device and use thereof

Abstract

The application discloses a resonant unit of a ventilated ultra-wideband low-frequency sound insulation device and application thereof. The resonant unit comprises a resonant chamber, a first end face and a second end face at two ends of the resonant chamber, and a ventilation channel perpendicular to the first end face and the second end face and penetrating through the resonant unit. The resonant chamber is surrounded by the first end face, the second end face, and first and second square frames with different sizes. The second square frame is smaller than the first square frame and is located at the center of the first square frame. The ventilation channel is formed in the second square frame. Four third square frames with one missing corner are arranged at four corners of the resonant chamber. An end cover port is arranged on the first end face and is connected with the second channel and the outside. The thickness of the resonant unit reaches 0.14 lambda, and the resonant unit has the subwavelength characteristic. A thin resonant unit can also achieve a good sound insulation effect. The ventilation channel is arranged, good ventilation performance is achieved, and the resonant unit can be applied to various ventilation environments.

Description

Technical Field

[0001] This invention relates to the field of noise control, specifically to a resonant unit of a ventilable ultrawideband low-frequency sound insulation device and its application. Background Technology

[0002] In modern life, noise pollution is becoming increasingly severe, constantly impacting human health and quality of life. Prolonged exposure to noise can lead to serious psychological and physiological problems, such as nausea, headaches, and fatigue. Sound insulation is one of the main technical measures in noise control. Common sound-absorbing / insulating units mainly include various types such as Helmholtz resonators, Fabry-Pérot resonators, thin-film resonators, split-ring resonators, coherent perfect absorbers, and ultrathin metasurface absorbers. Most of these units are designed based on local resonance mechanisms. By exciting resonance, external sound energy is reflected or absorbed into the unit's interior, where it is dissipated. This allows for the simultaneous achievement of subwavelength structures and high-performance sound absorption / insulation. However, the characteristics of resonance mean that the operating frequency band of these units is usually relatively narrow. Although combining multiple units with different operating frequency bands can effectively increase the bandwidth, adding too many units also increases the structural thickness.

[0003] Furthermore, traditional anechoic / sound insulation units typically have a sealed structure, which, while effectively blocking the propagation of sound through the air, also hinders the free flow of air, making these structures unsuitable for applications requiring air circulation. However, in certain specific scenarios, it is often necessary to allow the free flow and exchange of air, light, and heat while achieving noise control. Therefore, there is a need to propose a method that achieves ventilation while ensuring ultra-wideband sound insulation. Summary of the Invention

[0004] To achieve both ventilation and ultra-wideband sound insulation, this invention provides a resonant unit of a ventilable ultra-wideband low-frequency sound insulation device and its application. By setting a ventilation channel, the resonant unit can be ventilated, and by combining the structural design of the resonant chamber, an ultra-wideband sound insulation effect can be guaranteed.

[0005] The technical solution adopted in this invention is:

[0006] A resonant unit for a ventilable ultra-wideband low-frequency sound insulation device, the resonant unit comprising a resonant chamber, a first end face and a second end face at both ends of the resonant chamber, and a ventilation channel perpendicular to the first end face and the second end face and completely penetrating the resonant unit. The resonant chamber is formed by the first end face, the second end face, and a first square frame and a second square frame of different sizes. The second square frame is smaller than the first square frame and is located at the center of the first square frame. The ventilation channel is formed in the middle of the second square frame. Four third square frames with a missing corner are provided at the four corners of the resonant chamber. The missing corners of the four third square frames are directly opposite the four corners of the second square frames. A first channel is formed between the third square frames and the first square frames. A second channel is formed between adjacent third square frames. A third channel is formed between the third square frames and the second square frames. The third channel connects the second channel and the inner chamber of the third square frames. An end cap is provided on the first end face to connect the second channel to the outside.

[0007] Furthermore, the side length of the resonant unit is D, the width c of the first channel is 0.01D to 0.2D, the width w of the second channel is 0.03D to 0.25D, the width b of the third channel is 0.02D to 0.16D, the width t of the first square frame, the second square frame, and the third square frame is 0.01D to 0.03D, the width a of the ventilation channel is 0.3D to 0.5D, the thickness h of the first end face and the second end face is 1.5mm, and the total thickness H of the resonant unit is 3cm.

[0008] Furthermore, the side length D of the resonant unit is 8cm ≤ D < 16cm.

[0009] Furthermore, the resonant unit material is made of plexiglass or resin.

[0010] The purpose of the resonant unit is that several identical resonant units are arranged in an array along the horizontal and vertical directions, and the adjacent resonant units are closely fitted to form a ventilation and sound insulation barrier.

[0011] Furthermore, the operating frequency band of the formed ventilation and sound barrier is 700-2900Hz.

[0012] The purpose of the resonant unit is to place it inside a square ventilation duct, with its four sides fitting against the four sides of the inner wall of the square ventilation duct, for noise reduction of the square ventilation duct.

[0013] Furthermore, the noise reduction device used for the square ventilation duct operates in the frequency band of 700-2900Hz.

[0014] The purpose of the resonant unit is that several identical resonant units are arranged in an array along the horizontal and vertical directions, and the adjacent resonant units are closely fitted to form a resonant unit group. Multiple resonant unit groups are arranged in an array, and the ventilation channel width 'a' of different layers of resonant unit groups is different. The interval 'd' between adjacent layers of resonant unit groups is 1 to 15 cm, forming a multi-layer ventilation and sound insulation barrier.

[0015] Furthermore, the multi-layer ventilated sound barrier is composed of three layers of resonant units arranged in an array, with an interval of d = 5cm between adjacent layers of resonant units. The ventilation channel widths a of the three layers of resonant units are a = 5cm, a = 4cm, and a = 3cm, respectively, and the operating frequency band is 630-3520Hz.

[0016] The beneficial effects of this invention are:

[0017] The resonant unit of this invention has a thickness of 0.14λ, which is a subwavelength dimension and possesses subwavelength characteristics. Even a thinner resonant unit can achieve good sound insulation. The resonant unit achieves sound insulation based on two effects: sound energy reflection and absorption. The sound energy absorption effect is based on the excitation of the intrinsic resonant mode of the resonant unit. Sound energy is drawn into the resonant cavity and dissipated through the viscous friction between the air and the resonant unit walls in the first and second narrow channels. The sound energy reflection effect is based on the hollow structure of the resonant cavity. Because the resonant cavity is hollow, sound waves are reflected between the air and the resonant cavity walls, resulting in multiple reflections. This causes the sound waves to propagate continuously within the structure, and at specific frequencies, resonance occurs. At this point, the impedance of the resonant unit decreases, allowing it to absorb more sound energy, thereby reducing noise propagation and reflection. Furthermore, the ventilation channels on the resonant unit allow airflow, achieving good ventilation performance and making it suitable for various ventilation environments. The resonant unit operates in a frequency band of 700-2900Hz. The operating frequency band can be adjusted by changing the width a of the ventilation channel and / or the width w of the second channel to make it suitable for different working environments.

[0018] The ventilated sound barrier constructed from the resonant unit described in this invention exhibits excellent low-frequency broadband sound insulation performance when the side length of the resonant unit D = 10cm, the width of the first channel c = 4mm, the width of the second channel w = 10mm, the width of the third channel b = 4mm, the width of the first square frame, the second square frame, and the third square frame t = 1.5mm, the width of the ventilation channel a = 4cm, the thickness of the first end face and the second end face h = 1.5mm, and the total thickness of the resonant unit H = 3cm. When the resonant unit described in this invention is applied to a square ventilation duct, and the side length D of the resonant unit is 10cm, the width of the first channel is c=4mm, the width of the second channel is w=10mm, the width of the third channel is b=4mm, the width of the first square frame, the second square frame, and the third square frame is t=1.5mm, the width of the ventilation channel is a=4cm, the thickness of the first end face and the second end face is h=1.5mm, and the total thickness of the resonant unit is H=3cm, the transmittance is less than 0.1 in the 790-2780Hz wideband, and the relative bandwidth reaches 111.5%, with a minimum transmittance of 0.0006 at 950Hz, exhibiting a near-perfect sound insulation effect. The resonant unit described in this invention can also form a multi-layered ventilated sound barrier, which on the one hand broadens the working frequency range of the ventilated sound barrier, and on the other hand improves the sound insulation effect. When the widths a of the three ventilation channels along the sound wave incident direction are a = 5cm, a = 4cm, and a = 3cm, and the interval d between adjacent resonant unit groups is 5cm, the sound energy transmittance is less than 0.1 in the frequency range of 630-3520Hz, and as low as 0.0000015 at 3200Hz, with a relative bandwidth of 139.2%, exhibiting excellent ultra-wideband sound insulation performance.

[0019] The resonant unit proposed in this invention has high-performance ultra-wideband sound insulation performance, while also achieving good ventilation performance. It has a simple structure, is easy to process and manufacture, and is easy to install, making it widely applicable in fields such as noise control, architectural acoustics, and environmental protection. Attached Figure Description

[0020] Figure 1 This is a cross-sectional view of the resonant unit in Embodiment 1 of the present invention.

[0021] Figure 2 This is a 3D printed sample image of the resonant unit according to Embodiment 1 of the present invention, wherein... Figure 2 (a) is a cross-sectional view. Figure 2 (b) Main view Figure 2 (c) is the rear view.

[0022] Figure 3This is a graph showing the relationship between the ventilation channel width 'a' and the resonant frequency of the resonant unit described in Embodiment 1 of the present invention.

[0023] Figure 4 This is a graph showing the relationship between the second channel width w and the resonant frequency of the resonant unit described in Embodiment 1 of the present invention.

[0024] Figure 5 This is a schematic diagram of the ventilation and sound barrier described in Embodiment 2 of the present invention.

[0025] Figure 6 This is a schematic diagram of the experimental measurement device for the acoustic absorption performance of the resonant unit as described in Embodiment 2 of the present invention.

[0026] Figure 7 This is a spectrum of sound energy transmittance measured and simulated in the experiment of the ventilation sound barrier described in Embodiment 2 of the present invention.

[0027] Figure 8 This is a spectrum diagram of the sound energy transmittance, absorption rate, and reflectance simulated by the ventilation and sound barrier described in Embodiment 2 of the present invention.

[0028] Figure 9 This is a schematic diagram of the resonant unit used in a square ventilation duct according to Embodiment 3 of the present invention, wherein the resonant unit is a side view.

[0029] Figure 10 This is a transmittance spectrum diagram of the resonant unit used in a square ventilation duct according to Embodiment 3 of the present invention.

[0030] Figure 11 This is a schematic diagram of the multi-layered ventilation and sound barrier described in Embodiment 4 of the present invention.

[0031] Figure 12 This is a transmittance spectrum diagram of the multi-layer ventilation and sound insulation barrier described in Embodiment 4 of the present invention.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1. Resonance unit, 2. Power amplifier, 3. Data controller, 4. Computer, 5. Miniature microphone, 6. Sound source, 7. Sound-absorbing sponge, 8. Waveguide, 9. Inner wall of the pipe, 101. First square frame, 102. Second square frame, 103. Third square frame, 104. Ventilation channel, 105. First end face, 106. Second end face, 107. End cap, 108. First channel, 109. Second channel, 110. Third channel. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0035] Example 1

[0036] like Figure 1 and Figure 2 As shown, the resonant unit includes a resonant chamber, a first end face 105 and a second end face 106 at both ends of the resonant chamber, and a ventilation channel 104 perpendicular to the first end face 105 and the second end face 106 and completely penetrating the resonant unit. The resonant chamber is surrounded by the first end face 105, the second end face 106, and a first square frame 101 and a second square frame 102 of different sizes. The second square frame 102 is smaller than the first square frame 101 and is located at the center of the first square frame 101. The ventilation channel 104 is formed in the middle of the second square frame 102. Four ventilation channels with... are provided at the four corners of the resonant chamber. A three-dimensional frame 103 with a missing corner, the missing corners of the four three-dimensional frames 103 are directly opposite the four corners of the second square frame 102, a first channel 108 is formed between the three-dimensional frames 103 and the first square frame 101, a second channel 109 is formed between adjacent three-dimensional frames 103, a third channel 110 is formed between the three-dimensional frames 103 and the second square frame 102, and the third channel (110) connects the second channel 109 and the inner cavity of the three-dimensional frame 103, and an end cap 107 is provided on the first end face 105 to connect the second channel 109 with the outside. The resonant unit has a side length of D, the width c of the first channel 108 is 0.01D to 0.2D, the width w of the second channel 109 is 0.03D to 0.25D, the width b of the third channel 110 is 0.02D to 0.16D, the width t of the first square frame 101, the second square frame 102, and the third square frame 103 is 0.01D to 0.03D, the width a of the ventilation channel 104 is 0.3D to 0.5D, the thickness h of the first end face 105 and the second end face 106 is 1.5mm, and the total thickness H of the resonant unit is 3cm. The resonant unit of the silencing device can be fabricated using 3D printing technology, and the material used can be either plexiglass or resin.

[0037] Simulations were performed using the finite element software COMSOL. A resonant unit was constructed with a side length D = 10 cm, a width c = 4 mm for the first channel 108, a width w = 10 mm for the second channel 109, a width b = 4 mm for the third channel 110, a width t = 1.5 mm for the first square frame 101, the second square frame 102, and the third square frame 103, and a thickness h = 1.5 mm for the first end face 105 and the second end face 106. The total thickness of the resonant unit was H = 3 cm, and the material had a density of 1180 kg / m³. 3 Epoxy resin with a longitudinal wave velocity of 2720 m / s and a transverse wave velocity of 1460 m / s was used, with simulated environmental parameters including an air density of 1.21 kg / m³. 3With a sound velocity of 343 m / s, by changing the width 'a' of the ventilation channel 104, the sound transmittance of the resonant unit at different frequencies for different ventilation channel 104 widths 'a' was simulated and measured, and the results were obtained. Figure 3 The diagram showing the relationship between sound transmittance, the width a of ventilation channel 104, and resonant frequency indicates that the operating frequency of the resonant unit can be adjusted by adjusting the width a of ventilation channel 104. The width a of ventilation channel 104 is 3-5 cm, and the operating frequency adjustment range is 700-2900 Hz.

[0038] Simulations were performed using the finite element software COMSOL. A resonant unit was constructed with a side length D = 10 cm, a width c = 4 mm for the first channel 108, a width b = 4 mm for the third channel 110, a width t = 1.5 mm for the first square frame 101, the second square frame 102, and the third square frame 103, a width a = 4 cm for the ventilation channel 104, and a thickness h = 1.5 mm for the first end face 105 and the second end face 106. The total thickness of the resonant unit was H = 3 cm, and the material had a density of 1180 kg / m³. 3 Epoxy resin with a longitudinal wave velocity of 2720 m / s and a transverse wave velocity of 1460 m / s was used, with simulated environmental parameters including an air density of 1.21 kg / m³. 3 With a sound velocity of 343 m / s, by changing the width w of the second channel 109, the sound transmittance of the resonant units with different widths w of the second channel 109 at different frequencies was simulated and measured, and the results were obtained. Figure 4 The diagram showing the relationship between sound transmittance and the width w of the second channel 109 and the resonant frequency indicates that the operating frequency of the resonant unit can be adjusted by adjusting the width w of the second channel 109. The width a of the ventilation channel 104 is 3-15 mm, and the operating frequency adjustment range is 700-2900 Hz.

[0039] Example 2

[0040] like Figure 5 As shown, several identical resonant units are arranged in an array along the horizontal and vertical directions, and the adjacent resonant units are closely fitted to form a ventilation and sound insulation barrier.

[0041] like Figure 6As shown, the simulation experiment was verified using a four-sensor measurement method. The experimental setup includes a power amplifier 2, a data controller 3, a computer 4, a miniature microphone 5, sound-absorbing sponge 7, and a waveguide 8. The resonant unit of the test sample 1 is placed in the middle of the waveguide 8. Four acquisition points are set on the wall of the waveguide 8, and the four acquisition points are evenly distributed in pairs and set on both sides of the test sample. The miniature microphone 5 is set on the acquisition points and is connected to the data controller 3 for the acquisition and recording of sound wave information. The data controller 3 is connected to the computer 4 to realize the transmission of data and signals. The data controller 3 is connected to the sound source 6 through the power amplifier 2 to realize the control of the sound source 6. The sound source 6 is set at one end of the waveguide 8 to emit sound waves. Sound-absorbing sponge 7 is set at both ends of the waveguide 8 to absorb the residual sound waves after the test sample is soundproofed.

[0042] Select a density of 1180 kg / m³ 3 A resonant unit 1 with a side length D = 10cm, a width c = 4mm for the first channel 108, a width w = 10mm for the second channel 109, a width b = 4mm for the third channel 110, a width t = 1.5mm for the first square frame 101, the second square frame 102 and the third square frame 103, a width a = 4cm for the ventilation channel 104, a thickness h = 1.5mm for the first end face 105 and the second end face 106, and a total thickness H = 3cm is formed by 3D printing of an epoxy resin material with a longitudinal wave velocity of 2720m / s and a transverse wave velocity of 1460m / s. The resonant unit 1 is placed inside a waveguide 8 with the first end face 105 facing the sound source 6 so that the sound waves emitted by the sound source 6 are incident perpendicularly to the first end face 105. The waveguide 8 is made of plexiglass and its width is the same as the side length D of the resonant unit 1, which is 10cm. The sound wave is emitted by the parallel waveguide 8, and the miniature microphones 5 at both ends of the resonant unit 1 collect the sound wave information before and after sound insulation. The data is then transmitted by the data controller 3 to the computer 4 for recording and processing, resulting in... Figure 7 The spectrum of measured acoustic energy transmittance is shown in the figure.

[0043] Simulations were performed using the finite element software COMSOL. A resonant element was constructed with a side length D = 10 cm, a width c = 4 mm for the first channel 108, a width w = 10 mm for the second channel 109, a width b = 4 mm for the third channel 110, a width t = 1.5 mm for the first square frame 101, the second square frame 102, and the third square frame 103, a width a = 4 cm for the ventilation channel 104, a thickness h = 1.5 mm for the first end face 105 and the second end face 106, and a total thickness H = 3 cm. The material used was 1180 kg / m³. 3 Epoxy resin with a longitudinal wave velocity of 2720 m / s and a transverse wave velocity of 1460 m / s was used, with simulated environmental parameters including an air density of 1.21 kg / m³. 3With a sound speed of 343 m / s and a sound wave incident perpendicularly to the first end face at a angle of 105°, the relationship between sound energy transmittance and frequency was simulated, and the results were obtained. Figure 7 The simulated acoustic energy transmittance spectrum, and the simulated relationship between absorption, transmittance, reflectance and frequency shown in the figure, yield the following results. Figure 8 The spectrum diagrams shown are for absorptivity, transmittance, and reflectivity.

[0044] from Figure 7 As can be seen, the simulation and measurement results agree well, and the sound energy transmittance of the ventilated sound barrier is less than 0.1 in the frequency range of 834-2395Hz, and as low as 0.001 at 947Hz, with a relative bandwidth of 96.7%, demonstrating excellent low-frequency broadband sound insulation performance. The setting of ventilation channel 104 on the resonant unit achieves good ventilation performance. In this experiment, the operating frequency range of the resonant unit was 834-2395Hz, with the median operating frequency being 1614.5Hz, at which wavelength λ was...

[0045]

[0046] Where v is the speed of sound and f is the frequency. The ambient sound speed is 343 m / s, and the calculated wavelength λ = 0.2124 m is given. The total thickness of the resonant unit H = 3 cm, reaching 0.14λ, which is a subwavelength dimension and has subwavelength characteristics, ensuring the sound attenuation effect of the resonant unit in the low-frequency range.

[0047] Figure 8 The image shows the magnitude of sound energy transmittance and absorption in different regions, demonstrating that the ultra-wideband sound insulation of the resonant unit involves both reflection and absorption effects. Specifically, band I (834-1150Hz) is based on the combined effects of reflection and absorption; bands II (1150-1450Hz) and IV (1730-2395Hz) mainly rely on reflection; and band III (1450-1730Hz) is mainly due to the absorption effect of the structure. The sound energy absorption effect is based on the excitation of the intrinsic resonance mode of the resonant unit. Sound energy is absorbed into the unit and dissipated through the viscous friction between the air and the walls in the narrow channel. The sound reflection effect is based on the hollow cuboid structure. Because the resonant chamber is hollow, sound waves are reflected between the air and the walls of the resonant chamber, resulting in multiple reflections. This causes the sound waves to propagate continuously within the structure, and at specific frequencies, resonance occurs. At this time, the impedance of the resonant unit decreases, allowing it to absorb more sound energy, thereby reducing noise propagation and reflection.

[0048] Example 3

[0049] like Figure 9As shown, the resonant unit is placed inside a square ventilation duct, with its four sides fitting against the four sides of the inner wall 9 of the square ventilation duct, for noise reduction. The side length D of the resonant unit is equal to the side length of the inner wall 9 of the square ventilation duct.

[0050] Simulation was performed using the finite element software COMSOL. A square ventilation duct with a side length of 10cm was constructed, with 9 sections of the inner wall. Simultaneously, a resonant element with a side length D = 10cm was constructed. The widths of the first channel 108 (c = 4mm), the second channel 109 (w = 10mm), and the third channel 110 (b = 4mm) were also constructed. The widths of the first square frame 101, the second square frame 102, and the third square frame 103 were t = 1.5mm. The width of the ventilation channel 104 (a = 4cm) was 4cm. The thicknesses of the first end face 105 and the second end face 106 were h = 1.5mm. The total thickness of the resonant element was H = 3cm. The material used was 1180kg / m³. 3 Epoxy resin with a longitudinal wave velocity of 2720 m / s and a transverse wave velocity of 1460 m / s was used, with simulated environmental parameters including an air density of 1.21 kg / m³. 3 With a sound speed of 343 m / s, resonant unit 1 is placed inside a square ventilation duct, with its four sides fitting against the four sides of the inner wall 9 of the duct. Sound waves are incident perpendicularly to the first end face 105. The relationship between sound energy transmittance and frequency is simulated to obtain... Figure 10 The transmittance spectrum is shown below. Figure 10 It can be seen that when the resonant unit is applied to a square ventilation duct, the transmittance is less than 0.1 in the 790-2780Hz wide frequency band, and the relative bandwidth reaches 111.5%. Among them, it is as low as 0.0006 at 950Hz, showing a near-perfect sound insulation effect. Moreover, the setting of the ventilation channel 104 of the resonant unit will not affect the ventilation of the ventilation duct and can adapt to the needs of various ventilation environments.

[0051] Example 4

[0052] like Figure 11 As shown, several identical resonant units are arranged in an array along the horizontal and vertical directions. The adjacent resonant units are closely fitted to form a resonant unit group. The multi-layer resonant unit groups are arranged in an array. The ventilation channel 104 of different layers of resonant unit groups has different widths a. The interval d between adjacent layers of resonant unit groups is 1 to 15 cm, forming a multi-layer ventilation and sound insulation barrier.

[0053] Simulations were performed using the finite element software COMSOL. The resonant unit was constructed with a side length D = 10 cm, a width c = 4 mm for the first channel 108, a width w = 10 mm for the second channel 109, a width b = 4 mm for the third channel 110, a width t = 1.5 mm for the first square frame 101, the second square frame 102, and the third square frame 103, a thickness h = 1.5 mm for the first end face 105 and the second end face 106, and a total thickness H = 3 cm for the resonant unit. Three resonant units with widths a = 5 cm, a = 4 cm, and a = 3 cm for the ventilation channel 104 were constructed. The material used had a density of 1180 kg / m³. 3 Epoxy resin with a longitudinal wave velocity of 2720 m / s and a transverse wave velocity of 1460 m / s was used, with simulated environmental parameters including an air density of 1.21 kg / m³. 3 With a sound speed of 343 m / s, several ventilation channels 104 with the same width 'a' are arranged in an array along the horizontal and vertical directions. Adjacent resonant units are closely fitted to form a resonant unit group. These three resonant unit groups with width 'a' of the three ventilation channels 104 are arranged in three layers. Sound waves are incident perpendicularly to the first end face 105. Along the sound wave incident direction, the widths 'a' of the three ventilation channels 104 are a = 5 cm, a = 4 cm, and a = 3 cm, respectively. The interval between adjacent resonant unit groups is 'd' = 5 cm. The relationship between transmittance and frequency is simulated to obtain... Figure 12 The transmittance spectrum of the multi-layered ventilated sound barrier is shown. Figure 12 It is known that the multi-layered ventilated sound barrier exhibits an acoustic energy transmittance of less than 0.1 in the frequency range of 630-3520Hz, and as low as 0.0000015 at 3200Hz, with a relative bandwidth of 139.2%, demonstrating excellent ultra-wideband sound insulation performance. Furthermore, the arrangement of the ventilation channels 104 in the resonant units allows airflow, achieving good ventilation performance. The array arrangement of the multi-layered resonant units broadens the operating frequency range of the ventilated sound barrier and improves the sound insulation effect.

[0054] The examples described are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments. Any obvious improvements, substitutions or modifications that can be made by those skilled in the art without departing from the essence of the present invention are within the protection scope of the present invention.

Claims

1. A resonant unit of a vented ultra- wideband low-frequency sound isolation device, characterized by: The resonance unit comprises a resonance chamber, a first end face (105) and a second end face (106) at both ends of the resonance chamber, a ventilation channel (104) perpendicular to the first end face (105) and the second end face (106) and completely penetrating through the resonance unit, the resonance chamber is surrounded by the first end face (105), the second end face (106) and first square frames (101) and second square frames (102) of different sizes, the second square frame (102) is smaller than the first square frame (101) and is located at the center of the first square frame (101), the ventilation channel (104) is formed in the second square frame (102), four third square frames (103) with a missing corner are arranged at the four corners of the resonance chamber, the missing corners of the four third square frames (103) are opposite to the four corners of the second square frame (102), the third square frame (103) and the first square frame (101) form a first channel (108), adjacent third square frames (103) form a second channel (109), the third square frame (103) and the second square frame (102) form a third channel (110), and the third channel (110) is in communication with the second channel (109) and the inner chamber of the third square frame (103), and the first end face (105) is provided with a cover port (107) in communication with the second channel (109) and the outside. The side length of the resonance unit is D, the width c of the first channel (108) is 0.01D-0.2D, the width w of the second channel (109) is 0.03D-0.25D, the width b of the third channel (110) is 0.02D-0.16D, the width t of the first square frame (101), the second square frame (102) and the third square frame (103) is 0.01D-0.03D, the width a of the ventilation channel (104) is 0.3D-0.5D, the thickness h of the first end face (105) and the second end face (106) is 1.5mm, and the total thickness H of the resonance unit is 3cm. The side length D of the resonance unit is 8cm≤D<16cm.

2. The resonant unit of claim 1, wherein: The resonance unit is made of organic glass or resin material.

3. Use of a resonance unit as claimed in any of claims 1-2, characterized in that: A plurality of identical resonance units are arranged in an array along the transverse and longitudinal directions, and adjacent resonance units are closely attached to form a ventilation and sound insulation barrier.

4. Use of a resonance cell according to claim 3, characterized in that: The working frequency band of the formed ventilation and sound insulation barrier is 700-2900Hz.

5. Use of a resonator unit according to any of claims 1-2, characterized in that: The resonance unit is placed inside the square ventilation duct, and the four sides of the resonance unit are attached to the four sides of the inner wall (9) of the square ventilation duct, for sound attenuation of the square ventilation duct.

6. Use of a resonance cell according to claim 5, characterized in that: The sound attenuation for the square ventilation duct has a working frequency band of 700-2900Hz.

7. Use of a resonator unit according to any of claims 1-2, characterized in that: A plurality of identical resonance units are arranged in an array along the transverse and longitudinal directions, and adjacent resonance units are closely attached to form a resonance unit group, a plurality of resonance unit groups are arranged in an array, the widths a of the ventilation channels (104) of the resonance unit groups in different layers are different, the spacing d between adjacent layers of resonance unit groups is 1-15cm, and a multi-layer ventilation and sound insulation barrier is formed.

8. Use of a resonance cell according to claim 7, characterized in that: The multilayer ventilation sound insulation barrier is arranged in an array by 3 layers of resonance unit groups, adjacent layers of resonance unit groups are spaced apart by d=5cm, and ventilation channels (104) of the 3 layers of resonance unit groups have widths a of a=5cm, a=4cm and a=3cm respectively, and the working frequency band is 630-3520Hz.

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