Harmonic sound absorption layer and harmonic sound absorber special for transformer substation and processing method of harmonic sound absorption layer and harmonic sound absorber

Abstract

The invention discloses a harmonic sound absorption layer special for a transformer substation, a harmonic sound absorber and a processing method of the harmonic sound absorption layer and the harmonic sound absorber. The harmonic sound absorption layer comprises a 100 Hz half-wavelength tube, a 200 Hz half-wavelength tube, a 300 Hz half-wavelength tube, a 400 Hz half-wavelength tube, a 500 Hz half-wavelength tube, a 500 Hz half-wavelength tube, a 400 Hz half-wavelength tube, a 300 Hz half-wavelength tube, a 200 Hz half-wavelength tube and a 100 Hz half-wavelength tube which are sequentially arranged at equal intervals in the width direction of the half-wavelength tube and extend from the same end of the harmonic sound absorption layer to the other end of the harmonic sound absorption layer. A 100Hz quarter-wavelength tube, a 200Hz quarter-wavelength tube and a 300Hz quarter-wavelength tube are further mounted in the residual space of the harmonic sound absorption layer, and by the adoption of the harmonic sound absorption structure, full-band sound absorption can be achieved, a higher harmonic sound absorption coefficient is achieved, and 100Hz-500Hz low-frequency harmonic noise of the transformer substation can be effectively absorbed.

Description

Technical Field

[0001] The present invention relates to the technical field of sound-absorbing materials, and particularly to a harmonic sound-absorbing layer and a harmonic sound-absorbing body for a substation, and a processing method thereof. Background Art

[0002] With the rapid development of the air transportation industry and the increasing improvement of people's living standards, the airworthiness standards for civil aircraft noise are getting higher and higher, which means new requirements for noise control technology. Aircraft engine noise is one of the main noise sources of aircraft, and controlling aircraft engine noise can effectively reduce aircraft noise. On the other hand, in order to improve the comfort of passengers in the cabin of civil aircraft, sound insulation and sound-absorbing materials need to be used for the cabin wall panels, which can effectively reduce the noise level in the cabin.

[0003] Currently, the passive noise control technology is relatively common and technically mature in the field of aircraft noise control. Common passive noise reduction mufflers include Herschel-Quincke (HQ) tubes, 1 / 4 wavelength tubes, and Helmholtz mufflers, etc. The HQ tube is also called an interference tube. The sound wave phase passing through the branch tube changes and interferes with the sound wave in the main tube to achieve noise control.

[0004] In order to simplify the HQ tube interference theory, optimize the layout form of the HQ tube, adapt to the application scenario of aircraft engine noise reduction, and at the same time further improve the low-frequency noise reduction performance of the HQ tube, in the prior art, and also in the applicant's previous literature "Design and Experimental Research of Subwavelength-Thickness Mufflers", a semi-wavelength tube interference theory was proposed. The theoretical model was calculated and analyzed, and the broadband noise reduction performance based on the semi-wavelength tube theory was preliminarily explored. Finally, experimental verification was carried out, which proved that the multi-branch half-wave tube has good broadband sound absorption potential. In future research, it can be designed as a space-folded structure acoustic metamaterial, so that it has a broadband sound absorption effect and a subwavelength thickness, making it have greater potential in noise reduction in various fields.

[0005] At the same time, taking the half-wave tube as the basic unit, a subwavelength sound-absorbing structure was designed, and a full-ventilation noise reduction solution was proposed based on this sound-absorbing structure. The sound absorption performance was explored by numerical calculation and experimental methods. The results show that: the designed sound-absorbing structure and the full-ventilation muffler both have good noise reduction effects at 330 - 460 Hz.

[0006] Based on the above prior art, the inventor of the present invention found that the perforated sound insulation and sound absorption board has limited low-frequency noise absorption ability, and it is necessary to optimize the aperture and increase the sound-absorbing material to improve the low-frequency absorption. Also, aiming at the characteristics of the 100 Hz - 500 Hz low-frequency harmonic noise in the substation, a harmonic sound-absorbing structure for enhancing the absorption of low-frequency noise was developed. Summary of the Invention

[0007] Objective of the Invention: The objective of the present invention is to provide a harmonic sound-absorbing layer, a harmonic sound-absorbing body and their processing methods for special use in a substation. The harmonic sound-absorbing structure adopting the structure of the present invention can achieve full-band sound absorption and has a stronger harmonic sound-absorption coefficient, and can effectively absorb the low-frequency harmonic noise of 100 Hz to 500 Hz in the substation.

[0008] Technical Solution:

[0009] A harmonic sound-absorbing layer for special use in a substation includes 100 Hz half-wavelength tubes, 200 Hz half-wavelength tubes, 300 Hz half-wavelength tubes, 400 Hz half-wavelength tubes, 500 Hz half-wavelength tubes, 500 Hz half-wavelength tubes, 400 Hz half-wavelength tubes, 300 Hz half-wavelength tubes, 200 Hz half-wavelength tubes, 100 Hz half-wavelength tubes which are arranged at equal intervals in sequence along the width direction of the half-wavelength tube and extend from the same end to the other end of the harmonic sound-absorbing layer. In the remaining space of the harmonic sound-absorbing layer, 100 Hz quarter-wavelength tubes, 200 Hz quarter-wavelength tubes, and 300 Hz quarter-wavelength tubes are also installed. Since the equivalent length of each half-wavelength tube is different, this gradually changing arrangement can better cover the noise in different frequency ranges. To further improve the sound-absorbing performance, 100 Hz, 200 Hz, and 300 Hz quarter-wavelength tubes are installed in the remaining space. The design of the quarter-wavelength tube can enhance the sound-absorbing ability for low frequencies, especially in the frequency band below 100 Hz, this configuration has a significant effect.

[0010] Furthermore, the equivalent length of the 100 Hz half-wavelength tube is 1700 mm, the equivalent length of the 200 Hz half-wavelength tube is 850 mm, the equivalent length of the 300 Hz half-wavelength tube is 567 mm, the equivalent length of the 400 Hz half-wavelength tube is 425 mm, and the equivalent length of the 500 Hz half-wavelength tube is 340 mm.

[0011] Furthermore, the 100 Hz quarter-wavelength tube is installed in the middle of the remaining space of the harmonic sound-absorbing layer, and the 200 Hz quarter-wavelength tube and the 300 Hz quarter-wavelength tube are symmetrically installed on both sides of the 100 Hz quarter-wavelength tube. The 200 Hz and 300 Hz quarter-wavelength tubes are located on both sides respectively, and this symmetrical structure helps to maximize the uniform sound absorption.

[0012] Furthermore, the equivalent length of the 100 Hz quarter-wavelength tube is 850 mm, the equivalent length of the 200 Hz quarter-wavelength tube is 425 mm, and the equivalent length of the 300 Hz quarter-wavelength tube is 283 mm.

[0013] Further, the 100 Hz quarter - wavelength tube, 200 Hz quarter - wavelength tube, and 300 Hz quarter - wavelength tube are all arranged in a coiled and folded manner. To save space and increase the effective surface area of the sound absorber, the quarter - wavelength tubes are designed in a coiled and folded form. This design enables the sound absorption tubes to have a smaller volume while still maintaining a high sound absorption efficiency, making it suitable for environments with limited space such as substations.

[0014] The present invention also discloses a harmonic sound absorber for special use in substations, which includes a perforated plate, a sponge sound - absorbing layer, a harmonic sound - absorbing layer, an asbestos sound - absorbing layer, and a back - plate housing arranged in sequence along the thickness direction. The harmonic sound - absorbing layer is the above - mentioned harmonic sound - absorbing layer.

[0015] Further, the thickness of the asbestos sound - absorbing layer is 3 mm.

[0016] The present invention also discloses a processing method for a harmonic sound absorber for special use in substations, which includes the following steps:

[0017] 1) Press the sponge sound - absorbing layer, the harmonic sound - absorbing layer, and the asbestos sound - absorbing layer into the back - plate housing in sequence;

[0018] 2) Spot - weld the perforated plate to the back - plate housing.

[0019] Beneficial effects: The harmonic sound - absorbing structure adopting the structure of the present invention can achieve full - band sound absorption and has a stronger harmonic sound - absorption coefficient, capable of effectively absorbing the 100 Hz - 500 Hz low - frequency harmonic noise in substations. Description of the Drawings

[0020] Figure 1 is an exploded schematic view of the harmonic sound absorber of the present invention;

[0021] Figure 2 is a schematic view of the harmonic sound - absorbing layer of the present invention;

[0022] Figure 3 is a plan view of the harmonic sound - absorbing layer of the present invention and an explanatory diagram of equivalent size calculation;

[0023] Figure 4 is a sound - absorption coefficient diagram of the harmonic sound absorber of the present invention;

[0024] Figure 5 is a sound - absorption coefficient diagram of the harmonic sound absorber of the prior art. Detailed Description of the Invention

[0025] To make the technical solutions of the present invention clearer, the following further describes the present invention in detail with reference to the accompanying drawings and specific embodiments.

[0026] Embodiment 1

[0027] As Figures 1-4As shown in the figure, a harmonic sound-absorbing layer for a substation includes 100Hz half-wavelength tubes, 200Hz half-wavelength tubes, 300Hz half-wavelength tubes, 400Hz half-wavelength tubes, 500Hz half-wavelength tubes, 500Hz half-wavelength tubes, 400Hz half-wavelength tubes, 300Hz half-wavelength tubes, 200Hz half-wavelength tubes, and 100Hz half-wavelength tubes that are arranged at equal intervals in the width direction of the half-wavelength tubes and extend from the same end of the harmonic sound-absorbing layer to the other end. In the remaining space of the harmonic sound-absorbing layer, 100Hz quarter-wavelength tubes, 200Hz quarter-wavelength tubes, and 300Hz quarter-wavelength tubes are also installed. The half-wavelength tubes are arranged at equal intervals in the order of 100Hz, 200Hz, 300Hz, 400Hz, and 500Hz, extending from one end point to the other end point. Since the equivalent lengths of each half-wavelength tube are different, this gradually changing arrangement can better cover the noise in different frequency ranges. To further improve the sound-absorbing performance, 100Hz, 200Hz, and 300Hz quarter-wavelength tubes are installed in the remaining space. The design of the quarter-wavelength tubes can enhance the sound-absorbing ability for low frequencies. Especially in the frequency band below 100Hz, this configuration has a significant effect.

[0028] Furthermore, the equivalent length of the 100Hz half-wavelength tube is 1700mm, the equivalent length of the 200Hz half-wavelength tube is 850mm, the equivalent length of the 300Hz half-wavelength tube is 567mm, the equivalent length of the 400Hz half-wavelength tube is 425mm, and the equivalent length of the 500Hz half-wavelength tube is 340mm. These lengths match the wavelengths of the corresponding frequencies, thus ensuring the best sound-absorbing effect at these specific frequencies.

[0029] Furthermore, the 100Hz quarter-wavelength tube is installed in the middle of the remaining space of the harmonic sound-absorbing layer, and the 200Hz quarter-wavelength tube and the 300Hz quarter-wavelength tube are symmetrically installed on both sides of the 100Hz quarter-wavelength tube. The positions of the quarter-wavelength tubes are arranged symmetrically. The 100Hz quarter-wavelength tube is in the middle, and the 200Hz and 300Hz quarter-wavelength tubes are on both sides respectively. This symmetrical structure helps to absorb sound as evenly as possible to the greatest extent.

[0030] Furthermore, the equivalent length of the 100Hz quarter-wavelength tube is 850mm, the equivalent length of the 200Hz quarter-wavelength tube is 425mm, and the equivalent length of the 300Hz quarter-wavelength tube is 283mm. These lengths are accurately calculated according to the wavelengths of the frequencies to ensure the resonance sound-absorbing effect at their respective frequencies.

[0031] Explanation of the calculation of the equivalent length dimensions Figure 3 As shown.

[0032] Further, the 100 Hz quarter - wavelength tubes, 200 Hz quarter - wavelength tubes, and 300 Hz quarter - wavelength tubes are all arranged in a coiled and folded manner. To save space and increase the effective surface area of the sound absorber, the quarter - wavelength tubes adopt a coiled and folded design. This design enables the sound absorption tubes to have a smaller volume while still maintaining a high sound absorption efficiency, making it suitable for environments with limited space such as substations.

[0033] Example 2

[0034] The present invention also discloses a harmonic sound absorber dedicated for substations, which includes a perforated plate, a sponge sound absorption layer, a harmonic sound absorption layer, an asbestos sound absorption layer, and a back - plate housing arranged in sequence along the thickness direction. The harmonic sound absorption layer is the harmonic sound absorption layer described in Example 1. The sponge sound absorption layer is mainly used to absorb high - frequency noise, while the harmonic sound absorption layer is mainly responsible for absorbing low - frequency noise, and the asbestos layer is used for further sound insulation and enhancing the sound absorption effect.

[0035] The perforated plate serves as an external barrier, enhancing the rigidity and stability of the structure.

[0036] The sponge sound absorption layer is mainly used to absorb high - frequency noise. The sound absorption effect of the sponge has a significant effect on higher - frequency noise.

[0037] The harmonic sound absorption layer is the sound absorption layer containing half - wavelength tubes and quarter - wavelength tubes in Example 1, and is mainly responsible for absorbing low - frequency (100 Hz - 500 Hz) harmonic noise.

[0038] The back - plate housing is used to carry and fix the above - mentioned various layer structures, ensuring the overall stability of the sound absorber.

[0039] Further, the thickness of the asbestos sound absorption layer is 3 mm. As the last barrier, it can absorb noise in the high - frequency band and provide more stability to the overall structure.

[0040] Example 3

[0041] The present invention also discloses a processing method for a harmonic sound absorber dedicated for substations, including the following steps:

[0042] 1) Press the sponge sound absorption layer, the harmonic sound absorption layer, and the asbestos sound absorption layer into the back - plate housing in sequence;

[0043] 2) Spot - weld the perforated plate to the back - plate housing.

[0044] This structure enhances the overall stability of the sound absorber and ensures the effectiveness of each layer of sound - absorbing material.

[0045] Comparative Example 1

[0046] This comparative example is prior art. For details, refer to the applicant's previous literature "Design and Experimental Research on Sub-wavelength Thickness Mufflers", a harmonic sound-absorbing layer dedicated to substations, consisting of five pairs of symmetric half-wavelength tubes, where the half-wavelength tubes are formed by coiled spaces. At the same time, to improve the utilization rate of the remaining surface space of the upper layer, three 1 / 4 wavelength tubes are installed in the remaining volume. One pair of the three 1 / 4 wavelength tubes is symmetric, and a 3 mm thick sponge is pasted on the surface of the sound absorber.

[0047] Figure 5 The sound absorption coefficient diagram of the prior art harmonic sound absorber is presented. From Figure 5 and Figure 4 the comparison, it can be seen that the harmonic sound-absorbing structure adopting the structure of the present invention can achieve full-band sound absorption and has a stronger harmonic sound absorption coefficient, and can effectively absorb the low-frequency harmonic noise of 100 Hz - 500 Hz in the substation.

[0048] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent shall be subject to the appended claims.

Claims

1. A harmonic sound absorbing layer dedicated to a substation, characterized in that: The invention comprises 100 Hz half-wavelength tubes, 200 Hz half-wavelength tubes, 300 Hz half-wavelength tubes, 400 Hz half-wavelength tubes, 500 Hz half-wavelength tubes, 500 Hz half-wavelength tubes, 400 Hz half-wavelength tubes, 300 Hz half-wavelength tubes, 200 Hz half-wavelength tubes and 100 Hz half-wavelength tubes which are arranged in sequence at equal intervals along the width direction of the half-wavelength tubes and extend from the same end to the other end of the harmonic sound absorbing layer, and the remaining space of the harmonic sound absorbing layer is also equipped with 100 Hz quarter-wavelength tubes, 200 Hz quarter-wavelength tubes and 300 Hz quarter-wavelength tubes.

2. A harmonic sound absorbing layer dedicated to a substation according to claim 2, characterized in that: The equivalent length of the 100 Hz half-wavelength tube is 1700 mm, the equivalent length of the 200 Hz half-wavelength tube is 850 mm, the equivalent length of the 300 Hz half-wavelength tube is 567 mm, the equivalent length of the 400 Hz half-wavelength tube is 425 mm, and the equivalent length of the 500 Hz half-wavelength tube is 340 mm.

3. The harmonic sound absorbing layer dedicated to a substation according to claim 1, characterized in that: The 100 Hz quarter-wave tube is installed in the middle of the remaining space of the harmonic sound absorbing layer, and the 200 Hz quarter-wave tube and the 300 Hz quarter-wave tube are symmetrically installed on both sides of the 100 Hz quarter-wave tube.

4. A harmonic sound absorbing layer dedicated to a substation according to claim 1 or 3, characterized in that: The equivalent length of the 100 Hz quarter-wave tube is 850 mm, the equivalent length of the 200 Hz quarter-wave tube is 425 mm, and the equivalent length of the 300 Hz quarter-wave tube is 283 mm.

5. A harmonic sound absorbing layer dedicated to a substation according to claim 1 or 3, characterized in that: The 100 Hz quarter-wave tube, the 200 Hz quarter-wave tube, and the 300 Hz quarter-wave tube are all distributed in a curled and folded manner.

6. A harmonic sound absorber for substation, characterized in that: The invention comprises a perforated plate, a sponge sound absorbing layer, a harmonic sound absorbing layer, an asbestos sound absorbing layer and a back plate shell which are sequentially arranged along the thickness direction, wherein the harmonic sound absorbing layer is the harmonic sound absorbing layer as claimed in any one of claims 1 to 5.

7. A harmonic sound absorber for substations according to claim 6, characterized in that: The thickness of the asbestos sound absorbing layer is 3mm.

8. A method for processing a harmonic sound absorber for a substation as claimed in claim 6 or 7, characterized in that: The following steps are involved: 1) Press the sponge sound absorbing layer, harmonic sound absorbing layer and asbestos sound absorbing layer into the back panel shell in sequence; 2) Spot weld the orifice plate to the backplane housing.

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