CN211446650U - Transparent sound absorption cap for top of sound insulation barrier - Google Patents
Transparent sound absorption cap for top of sound insulation barrier Download PDFInfo
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- CN211446650U CN211446650U CN201921564070.4U CN201921564070U CN211446650U CN 211446650 U CN211446650 U CN 211446650U CN 201921564070 U CN201921564070 U CN 201921564070U CN 211446650 U CN211446650 U CN 211446650U
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Abstract
The application provides a transparent sound absorption cap for the top of a sound insulation barrier, which comprises a shell and a micro-perforated plate; the shell is made by transparent material, the microperforated panel is fixed the top of shell, the microperforated panel is made by transparent material or translucent material, the microperforation has been seted up on the microperforated panel, the microperforated panel with the distance less than or equal to 100mm of shell bottom. According to the transparent sound absorption cap, the cavity depth of the transparent sound absorption cap is reduced, and meanwhile, the sound energy of a middle-low frequency band region reaches the sound absorption rate of more than 50%; the transparent sound absorption cap is attractive and practical, the structure is stable, and the sound absorption performance and the structural fastness can be enhanced by arranging the transverse partition plate made of transparent materials or sound absorption plates in the transparent sound absorption cap, so that a better sound insulation effect is achieved; the transparent equipment is arranged inside the transparent sound absorption cap, so that the street provided with the sound insulation barrier can be illuminated.
Description
Technical Field
The application relates to the technical field of silencers, in particular to a transparent sound absorption cap for the top of a sound insulation barrier.
Background
A sound barrier is a sound-insulating facility that, in order to block direct sound between the source and the recipient, interposes a facility between the source and the recipient to provide a significant additional attenuation of the sound wave propagation, thereby attenuating the noise impact in the area of the recipient. At present, the sound insulation barrier is mainly used for sound insulation and noise reduction in traffic municipal facilities such as expressways, overhead composite roads, urban light rails, subways and the like, and controlling the influence of traffic noise on nearby urban areas, and can also be used for sound insulation and noise reduction of factories and other noise sources.
In the ever-building highways, railways and industrial areas, the installation of sound barriers has become an indispensable noise reduction facility. To improve the sound insulation effect of the barrier, the height of the barrier is generally increased. However, the heightened barriers inevitably increase the cost of the barriers and the foundation construction, and have certain influence on light and the sight of road users.
When the height of the sound insulation barrier is kept, a sound absorption type sound absorption cap can be additionally arranged at the top of the sound insulation barrier for improving the sound insulation performance of the top of the sound insulation barrier. The sound absorption cap is mainly divided into a resistive sound absorption cap and a resistive sound absorption cap, the effective frequency band range of the resistive sound absorption cap is wider, but the sound insulation effect is usually not ideal enough, and the insertion loss of the resistive sound absorption cap can only reach about 2 dB; the resistant caps, although effective, can only act on individual frequency bands.
The secondary residual scattering (QRD) sound absorption cap developed in the beginning of the 21 st century consists of cavities with different depths and is used for the top of a sound insulation barrier, and the primary reason why the secondary residual scattering (QRD) sound absorption cap can disperse and absorb sound energy is as follows: acoustic impedances that vary greatly can be generated between adjacent cavities, and different cavities resonate or resonate at different frequencies to produce a sound absorption effect.
Sound absorption tests carried out in a reverberation chamber according to the standard ISO 354 show that the sound absorption rate of the secondary residual scattering (QRD) sound absorption cap to the medium frequency can reach up to 0.9 in the 315Hz to 400Hz frequency band; however, the depth of the secondary residual scattering (QRD) acoustic cap is up to 200mm, which is relatively large. Most of products designed by the micro-perforation theory can only reach relatively low sound absorption performance under the low frequency lower than 400Hz, and the sound absorption performance under the low frequency range is improved, and the depth of the cavity needs to be increased to reach 200mm or more.
Therefore, there is an urgent need for the development of a low-frequency sound-absorbing cap that reduces the depth of the cavity, and a sound-absorbing cap that can achieve high sound-absorbing performance for mid-low frequency noise at a small depth is required.
SUMMERY OF THE UTILITY MODEL
The application aims to provide a transparent sound absorption cap for the top of a sound insulation barrier, and the problem that the cavity depth needs to be increased to reach more than 200mm when the sound absorption performance is improved in a medium-low frequency band is solved.
In order to achieve the purpose, the following technical scheme is adopted in the application:
a transparent sound absorption cap for the top of a sound barrier comprises a shell and a micro-perforated plate; the shell is made by transparent material, the microperforated panel is fixed the top of shell, the microperforated panel is made by transparent material or translucent material, the microperforation has been seted up on the microperforated panel, the microperforated panel with the distance less than or equal to 100mm of shell bottom.
Further, the housing is made of glass and/or polycarbonate.
Further, the thickness of the micro-perforated plate is more than 1.5 mm.
Further, the diameter of the microperforations is within 0.5 mm.
Further, the perforation rate of the microperforated panel is within 0.5%.
Further, a transverse partition plate is arranged between the shell and the micro-perforated plate at intervals.
Further, the transverse partition is made of a transparent material or an acoustic panel.
Further, a lighting apparatus may be installed inside the transparent acoustic cap.
Further, the transparent sound absorption cap is octagonal.
Further, the microperforations on the microperforation panel are arranged in a rectangular or triangular pattern.
According to the transparent sound absorption cap for the top of the sound insulation barrier, the insertion loss performance of the sound insulation barrier is improved by inhibiting boundary potential energy and reducing a diffraction sound field by using the sound absorption principle of a micro-perforated plate, and the sound energy of a middle-low frequency band region reaches more than 50% of sound absorption rate while the cavity depth of the transparent sound absorption cap is reduced; the transparent sound absorption cap is attractive and practical, the structure is stable, and the sound absorption performance and the structural fastness can be enhanced by arranging the transverse partition plate made of transparent materials or sound absorption plates in the transparent sound absorption cap, so that a better sound insulation effect is achieved; the transparent equipment is arranged inside the transparent sound absorption cap, so that the street provided with the sound insulation barrier can be illuminated.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a view showing the type of a sound-absorbing cap installed on top of a sound-insulating barrier, in which fig. 1(a) is a resistive sound-absorbing cap, fig. 1(b) is a resistive sound-absorbing cap, and fig. 1(c) is an resistive sound-absorbing cap.
FIG. 2 is a schematic view of a method for testing the noise reduction effect of the acoustic absorption cap in the embodiment of the present application.
Fig. 3 is a diagram showing the results of the sound insulation test of three types of sound absorption caps, in which the abscissa represents frequency band and the unit represents HZ, and the ordinate represents improvement of sound insulation effect and the unit represents DB.
Fig. 4 is a noise transmission diagram of a transparent acoustic cap according to an embodiment of the present application mounted on top of an acoustic barrier.
Fig. 5 is an illumination view of the present application mounted inside a transparent acoustic cap.
Figure 6 is a cross-sectional view of a transparent acoustical cap incorporating a transverse partition in accordance with the present application.
Fig. 7 is a microperforation arrangement of a microperforation panel of the transparent acoustic cap for use in the top of an acoustic barrier according to the present application, wherein the microperforation arrangement of fig. 7(a) is rectangular and the microperforation arrangement of fig. 7(b) is triangular.
Fig. 8 is a graph comparing sound absorption coefficients of the first and second embodiments of the present application.
Fig. 9 is a graph comparing sound absorption coefficients of example three and example four of the present application.
The drawings illustrate the following:
1. a noise source; 2. a noise propagation direction; 3. a transparent sound absorbing cap; 4. a transparent sound-insulating barrier; 5. a noise receiver; 6. a building; 7. a lighting device; 8. lighting; 9. a pedestrian; 10. a vehicle; 11. a micro-perforated plate; 12. a transverse partition; 13. a housing.
Detailed Description
The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The transparent sound absorption cap is arranged at the top of the sound insulation barrier, so that the sound absorption cap has double functions of sound absorption and transparency, can improve the sound insulation effect of the sound insulation barrier while keeping a good sight effect, and has a good landscape coordination effect.
The sound barrier is essentially a barrier or partial barrier which substantially interferes with the propagation of sound waves and can block the propagation of sound waves to form an acoustic shadow region, the size of the "acoustic shadow region" of the sound barrier is related to the frequency of sound, and the higher the frequency is, the larger the extent of the acoustic shadow region is. The noise reduction effect is increased along with the increase of the path difference of the sound path, and a sound barrier which is high enough and long can reduce the noise of sound receiving points in an acoustic shadow area.
Through research calculation and experiments, different designs of the sound absorption cap at the top of the barrier are compared, and the sound insulation performance of the T-shaped sound absorption cap is most effective. As shown in fig. 1, fig. 1(a) is a resistive sound absorbing cap, the inside of which is T-shaped and is filled with glass wool, and then protected by a galvanized perforated iron plate. Fig. 1(b) is a resistant sound absorbing cap, which is muffled by the principle of resonance, so that a sound absorbing filler is not structurally required. Fig. 1(c) shows an impedance cap, in which a perforated iron plate is added to the impedance cap to satisfy the requirement that the impedance cap also has resistance.
According to the test method, ISO 10847 is taken as a reference, as shown in figure 2, the sound absorption cap is measured according to the position shown in the figure, then the sound absorption cap is covered by the galvanized iron sheet and the test is repeated, and the improvement of the sound insulation effect of the galvanized iron sheet sound absorption cap on the sound insulation barrier is obtained by subtracting the values measured at the two same positions.
From the test results shown in fig. 3, it can be seen that various types of sound absorption caps can improve the noise reduction effect, and particularly, the noise reduction effect is good for the sound energy in the middle and high frequency band region.
The resistive sound absorption cap absorbs and reduces noise diffraction at the top of the sound insulation barrier through the glass wool, so that the sound insulation effect of the sound insulation barrier is improved. In the medium and high frequency band, the sound insulation effect of the barrier can be improved by 1 to 1.5dB by the resistive sound absorption cap.
The resistant sound absorption cap utilizes a regular groove structure to delay and reflect incident noise, so that the partially reflected noise and the incident noise are mutually offset to obtain a more obvious improvement, as shown in figure 3, the resistant sound absorption cap can be close to 1000Hz, and the sound insulation effect is improved by nearly 3 dB. However, due to the size of the grooves, the sound insulation effect is mainly concentrated on 1000Hz, and the effect is relatively reduced in other frequency bands.
The effective frequency band of the resistive sound absorbing cap is increased compared to the resistive sound absorbing cap, wherein the performance of 2000Hz to 8000Hz is improved, thereby increasing the sound insulation effect to 4 dB.
When the cavity depth of the transparent sound absorption cap provided by the embodiment of the application only needs 50mm to 100mm, more than 50% of sound energy can be absorbed in the middle and low frequency band, and the sound absorption rate can reach 90% in the frequency band of 160Hz to 400 Hz. By reducing the depth of the transparent sound absorbing cap, the product is more aesthetically pleasing while maintaining high sound absorption performance down to mid frequency.
The transparent sound absorption cap of the embodiment of the application can be made of transparent materials such as organic glass (PMMA), Polycarbonate (PC) or glass, and when the transparent sound absorption cap is installed at the top of a transparent type sound insulation barrier, the transparent sound absorption cap is attractive, the transparency of the whole sound insulation system can be kept, and the transparent sound absorption cap is more harmonious with the surrounding environment.
In order to increase the sound absorption efficiency down to medium frequencies, the microperforated plates should have an airflow resistance of 1000 to 3500kN.s/m, measured according to standard ISO 90534In the meantime.
Microperforated panels reduce acoustic energy by frictional damping and pressure losses created by acoustic resonance of the aperture flow. In order to achieve the desired resistance to air flow, the microperforated PMMA or PC sheet should have a thickness of 1.5mm or more, a pore diameter of not more than 0.5mm, and a perforation rate of not more than 0.5%. The perforations may be arranged in any pattern, preferably in rectangular and triangular patterns.
The transparent sound absorption cap can be internally provided with a transverse clapboard made of transparent materials or sound absorption plates so as to enhance the sound absorption performance and the structural fastness of the sound absorption cap.
Another application is a design that combines acoustic and illumination, with microperforations in transparent and translucent plastic materials, and an illumination device may be mounted inside the transparent acoustic cap to provide illumination to the street or space in which the sound barrier is installed.
As shown in the test data of fig. 8, a transparent acoustic cap with a cavity depth of 50mm can absorb 50% of the acoustic energy in the frequency band from 200HZ to 630 HZ.
As shown in the test data of fig. 9, a transparent acoustic cap with a cavity depth of 100mm can absorb 50% of the acoustic energy in the frequency band from 125HZ to 500 HZ.
The application provides a transparent sound absorption cap 3 for the top of an acoustic barrier, which comprises a shell 13 and a micro-perforated plate 11; the shell 13 is made of transparent materials, the micro-perforated plate 11 is fixed on the top of the shell 13, micro-perforations are formed in the micro-perforated plate 11, and the distance between the micro-perforated plate 11 and the bottom of the shell 13 is less than or equal to 100 mm; the outer shell 13 is made of glass and/or polycarbonate, and the transparent sound absorption cap 3 is T-shaped; the micro-perforated plate 11 is made of transparent or semitransparent materials, the thickness of the micro-perforated plate 11 is more than 1.5mm, the diameter of the micro-perforated plate is within 0.5mm, the perforation rate of the micro-perforated plate 11 is within 0.5%, and the micro-perforated plate 11 has micro-perforated holes which are arranged in a rectangular or triangular shape; a transverse partition plate 12 is arranged between the shell 13 and the micro-perforated plate 11 at intervals; the transverse partition 12 is made of transparent material or acoustic panel; inside said transparent acoustic cap 3 a lighting device 7 can be mounted.
The application provides a transparent sound absorption cap 3 for sound insulation barrier top, the amortization principle that has combined resonant cavity formula reactive muffler and micropunch plate silencer, please refer to fig. 4 and show, noise source 1 that contains traffic noise gets into transparent sound absorption cap along noise propagation direction 2, behind the micropunch plate 11 at transparent sound absorption cap 3 top, the sound wave incides micropunch plate 11, under the excitation of sound wave, the air in the micropunch aperture and the air near the micropunch hole vibrate back and forth together, the friction damping during vibration makes a part of sound energy conversion heat energy consumption dispel, only remain a small part of sound energy and continue to propagate forward, thereby reduce the noise diffraction at sound insulation barrier top, reach the mesh of the noise elimination of making an uproar of falling. When the frequency of the sound wave is the same as the natural frequency of the resonant cavity, resonance is generated, the amplitude and the vibration speed of the reciprocating vibration of the air reach the maximum value, at the moment, the consumed sound energy is the largest, and the sound attenuation volume is the largest.
The transparent sound absorption cap for the top of the sound insulation barrier provided by the application has the advantages that the micro-perforations are uniformly distributed on the micro-perforated plate 11, the size and the shape of each micro-perforation can be the same or different, each micro-perforation can be regarded as a short pipe, and the length of each micro-perforation is the thickness of the micro-perforated plate 11. The microperforations in the microperforated plate 11 may be arranged in various shapes, and as shown in FIG. 7(a), the microperforations in the microperforated plate 11 may be arranged in a rectangular shape having a length and a width a, b, respectively, and the diameter of the two microperforations at the upper side of the rectangular shape is d1The diameter of the lower two micro-perforations is d2，d1D is less than or equal to2(ii) a As shown in FIG. 7(b), the microperforations in the microperforated plate 11 may be arranged in a triangular shape having a base with a length of a, two sides with a length of b, and a diameter of d1The diameter of the micro-perforation on the other vertex is d2。
According to the transparent sound absorption cap for the top of the sound insulation barrier, the thickness of the micro-perforated plate 11 is set to be 1.5mm, the diameter of the micro-perforated hole of the micro-perforated plate is 0.5mm, the perforation rate of the micro-perforated plate is 0.5%, and when the distance between the micro-perforated plate 11 and the bottom of the shell 13 is 50mm, 50% of sound energy can be absorbed in a frequency band from 200HZ to 630 HZ; when the distance between the micro-perforated plate 11 and the bottom of the housing 13 is 100mm, 50% of the sound energy can be absorbed in the frequency band of 125HZ to 500 HZ.
Example one
The transparent sound absorption cap 3 for the top of the sound insulation barrier provided by the embodiment is combined with the transparent sound insulation barrier or the sound absorption type barrier, and the insertion loss performance of the sound barrier is improved by inhibiting the boundary potential energy and reducing the diffraction sound field, so that a set of unique and beautiful sound insulation barrier system with the noise reduction function is formed. The length of the top of the outdoor sound insulation barrier is 1000mm, the depth of the transparent sound absorption cap 3 is 50mm, a micro-perforated plate 11 is installed on the top of the transparent sound absorption cap 3, the distance between the micro-perforated plate 11 and the bottom of the shell 13 is 50mm, the thickness of the micro-perforated plate 11 is 1.5mm, the diameter of the micro-perforated plate 11 is 0.5mm, the perforation rate of the micro-perforated plate 11 is 0.5%, and the micro-perforated plates of the micro-perforated plate 11 are arranged in a rectangular shape. As shown by the legend LxTA-50 in fig. 8, the transparent acoustic cap absorbs 50% of the acoustic energy in the 200HZ to 630HZ frequency band.
Example two
The second embodiment is different from the first embodiment mainly in that in the transparent sound absorption cap 3 of the second embodiment, a transparent transverse partition plate 12 capable of absorbing sound is additionally arranged between the micro-perforated plate 11 and the bottom of the outer shell 13, so that the sound absorption performance and the structural fastness of the transparent sound absorption cap 3 can be enhanced, and as shown in a legend LxTA-50F in FIG. 8, the transparent sound absorption cap can absorb 50% of sound energy in a frequency band from 200HZ to 630 HZ.
EXAMPLE III
The present embodiment provides a transparent cap for sound absorption 3 on top of an acoustic barrier, a design combining acoustics and illumination, micro-perforations are provided on a housing 13 of transparent or translucent material, and an illumination device can be installed inside the transparent cap for sound absorption 3 to provide illumination for the street or space where the acoustic barrier is installed. The length of the top of the outdoor sound insulation barrier is 1000mm, the depth of the transparent sound absorption cap 3 is 50mm, the lighting device 7 is arranged inside the transparent sound absorption cap 3, the micro-perforated plate 11 is arranged at the top of the transparent sound absorption cap 3, the distance between the micro-perforated plate 11 and the bottom of the shell 13 is 100mm, the thickness of the micro-perforated plate 11 is 1.5mm, the diameter of the micro-perforated plate 11 is 0.5mm, the perforation rate of the micro-perforated plate 11 is 0.5%, and the micro-perforations of the micro-perforated plate 11 are arranged in a triangle. As shown by the legend LxTA-100 in fig. 9, the transparent acoustic cap absorbs 50% of the acoustic energy in the 125HZ to 500HZ frequency band.
Example four
The fourth embodiment is different from the third embodiment mainly in that in the transparent sound absorption cap 3 of the fourth embodiment, a transparent transverse partition plate 12 capable of absorbing sound is additionally arranged between the micro-perforated plate 11 and the bottom of the outer shell 13, so that the sound absorption performance and the structural fastness of the transparent sound absorption cap 3 can be enhanced, and as shown in a legend LxTA-100F in fig. 9, the transparent sound absorption cap can absorb 50% of sound energy in a frequency band from 125HZ to 500 HZ.
The application provides a transparent sound absorption cap for sound insulation barrier top, can be higher than 50% to the sound absorption performance of low band noise when the cavity degree of depth is no longer than 100mm for install at open air transparent sound insulation barrier top, can increase the insertion loss performance of sound insulation barrier, reduce traffic noise, industrial noise and other kinds of well low frequency noise, reach the effect of the noise elimination of making an uproar of falling.
The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.
Claims (10)
1. A transparent acoustic cap for the top of an acoustic barrier comprising a housing and a microperforated panel; the shell is made by transparent material, the microperforated panel is fixed the top of shell, the microperforated panel is made by transparent material or translucent material, the microperforation has been seted up on the microperforated panel, the microperforated panel with the distance less than or equal to 100mm of shell bottom.
2. The transparent acoustical cap for a sound barrier top of claim 1 wherein the outer shell is made of glass and/or polycarbonate.
3. A transparent sound absorption cap for the top of a sound insulation barrier according to claim 1, wherein the microperforated plate has a thickness of 1.5mm or more.
4. A transparent sound absorbing cap for a sound barrier top according to claim 1, wherein the diameter of said micro-perforations is within 0.5 mm.
5. A transparent sound absorbing cap for the top of a sound barrier according to claim 1, wherein the perforated sheet has a perforation rate within 0.5%.
6. A transparent cap as claimed in claim 1, wherein a transverse partition is provided between the housing and the microperforated panel.
7. A transparent cap for the absorption of sound for the top of sound-insulating barriers according to claim 6, characterised in that the transverse partitions are made of transparent material or of sound-absorbing panels.
8. The transparent sound absorbing cap for the top of a sound-insulating barrier as claimed in claim 1, wherein a lighting fixture is installed inside the transparent sound absorbing cap.
9. A transparent sound absorbing cap for a sound barrier top as claimed in claim 1, wherein said transparent sound absorbing cap is octagonal.
10. A transparent sound absorbing cap for the top of a sound barrier according to claim 1, characterized in that the microperforations on said microperforated panel are arranged in a rectangular or triangular pattern.
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| CN110485322A (en) * | 2019-09-19 | 2019-11-22 | 盈普声学（惠州）有限公司 | A kind of transparent sound absorption cap at the top of acoustic barrier |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110485322A (en) * | 2019-09-19 | 2019-11-22 | 盈普声学（惠州）有限公司 | A kind of transparent sound absorption cap at the top of acoustic barrier |
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