Sound Barrier Based on Spatially Coiled Square Super-Element Array and Its Optimization Design Method

Abstract

The present invention discloses a sound barrier based on a spatially coiled square supercell array and its optimized design method. The invention relates to the technical field of sound barriers and includes a square supercell. A number of groups of the square supercells are provided and distributed in an array. The square supercells are designed to be square-shaped and surrounded by four groups of spatially coiled boxes. The present invention forms a sound barrier by stacking the square supercells distributed in an array, and partitions a coiled channel inside the spatially coiled box through a partition. The structure of the square supercell includes two parts, namely an outer square ring coiled area and a middle ventilation open area. It is not only simple to manufacture, but also has good ventilation performance, and can ensure that the ventilation performance meets the standard while ensuring good sound insulation effect. In addition, the present invention also realizes the optimization of the noise reduction performance of the sound barrier through an automatic optimization design method. By adopting this optimized design method, the simulation calculation time can be greatly saved, the design efficiency is improved, and it becomes possible to select the optimal size from a large number of geometric design parameters.

Description

Technical Field

[0001] The present invention relates to the technical field of sound barriers, and particularly to a sound barrier based on a spatially coiled square supercell array and an optimization design method thereof. Background Art

[0002] A sound barrier is a facility used to reduce the impact of noise. It reduces the impact of noise on the surrounding environment and the human body by blocking the propagation of sound waves. The principles of a sound barrier mainly include three mechanisms: reflection, sound absorption, and sound insulation. Sound barriers are widely used in fields such as architectural design, transportation, and heavy machinery cabins. In actual application scenarios, it is often required that the sound barrier carry out noise control under the condition of ensuring good air circulation. For example, natural ventilation is a key part of architectural design, which inevitably causes residents to be affected by the accompanying noise, thus generating the need for a sound-insulating and breathable structure; mechanical cabins not only need to be sound-insulated, but also need to dissipate heat through the air exchange between the internal and external environments; the aerodynamic load acting on the sound barriers along the line by high-speed trains cannot be ignored, which also requires the sound barrier to have a certain ventilation capacity while exerting its noise reduction performance to ensure its structural safety and the smooth operation of the train. Most traditional sound barriers have problems such as poor sound insulation effect or unqualified ventilation.

[0003] In recent years, the emergence and use of acoustic metamaterials have provided an effective way to solve the above problems, especially the attenuation and selective action on waves in specific frequency bands. Acoustic metamaterials are widely used in various fields, such as acoustic invisibility, sub-wavelength imaging, transmission or reflection control, etc. With the continuous development of acoustic metamaterials, spatially coiled metamaterials, topological acoustics, fractal acoustic metamaterials, helical structure metamaterials, and acoustic metasurfaces have been successively proposed. However, the structural forms of the above acoustic metamaterial sound barriers are all too complex, and their manufacturing and installation costs are too high. In addition, few metamaterial sound barriers obtain the optimal structural parameters through an automatic optimization program.

[0004] In summary, traditional sound barriers either have poor sound insulation effect or unqualified ventilation, and always need to make a trade-off between sound insulation and ventilation performance, and cannot ensure qualified ventilation performance while ensuring good sound insulation effect. And currently, various mainstream acoustic metamaterial sound barriers also have problems such as complex structural forms and inability to automatically optimize structural parameters. Therefore, the present invention proposes a sound barrier based on a spatially coiled square supercell array and an optimization design method thereof to solve the problems existing in the prior art. Summary of the Invention

[0005] Aiming at the above problems, the purpose of the present invention is to propose a sound barrier based on a spatially coiled square supercell array and an optimization design method thereof, which solves the problems that traditional sound barriers either have poor sound insulation effect or unqualified ventilation, and that various mainstream acoustic metamaterial sound barriers currently also have complex structural forms and cannot complete the automatic optimization of structural parameters.

[0006] To achieve the object of the present invention, the present invention is realized through the following technical solutions: A sound barrier based on a spatially coiled square supercell array, which includes square supercells. A number of groups of the square supercells are provided and distributed in an array. The square supercells are designed to be square-shaped and surrounded by four groups of spatially coiled boxes. The spatially coiled box includes a square frame body and a partition fixed inside the square frame body. The front and rear sides of the square frame body are designed to be open. The partitions are staggered inside the square frame body to form coiled channels.

[0007] A further improvement lies in that: the height of the partition is less than the height of the square frame body, and the height of the coiled channel is greater than the height of the partition.

[0008] A further improvement lies in that: a square hole surrounded by four groups of spatially coiled boxes is provided at the middle position of the square supercell for air flow to pass through.

[0009] A further improvement lies in that: seven groups of partitions are provided. Four of the seven groups of partitions are fixed to one side inside the square frame body, and the other three groups of partitions are fixed to the other side inside the square frame body.

[0010] A further improvement lies in that: six groups of coiled channels are provided. The six groups of coiled channels are symmetrically distributed in a mirror image with the partition at the middle position inside the square frame body as the center line.

[0011] A further improvement lies in that: the thickness of the square supercell is equal to the sum of the total thickness of the partitions and the total thickness of the coiled channels.

[0012] An optimization design method for a sound barrier based on a spatially coiled square supercell array includes the following steps:

[0013] Step 1: Define global parameters in the COMSOL software, establish an acoustic finite element model of the square supercell, and run the frequency domain study calculation and solution. Draw the transmission loss curve according to the solution calculation results, and export the solution calculation data at the same time;

[0014] Step 2: Use the APP developer module built in the COMSOL software to create a new method for frequency domain study calculation and result data export code in the method branch. Return to the model developer module and add the call of this method;

[0015] Step 3: Enter the COMSOL command in the Windows command prompt CMD to modify the model parameters, and call the new method created in Step 2 to complete the model calculation after modifying the parameters once to obtain the result data;

[0016] Step 4: Write an external program to traverse parameters, call CMD, and implement the loop to modify the input COMSOL command string multiple times, traverse all dimension parameters within the preset range, repeat Step 3, and calculate and export the transmission loss result data corresponding to all models within the preset parameter range in sequence;

[0017] Step 5: Use a screening program to determine the optimal dimension parameters, traverse all the calculation result data in Step 4, screen out the combination of dimension parameters that maximizes the average transmission loss of all models within the target frequency band, and use it as the optimal dimension parameters.

[0018] A further improvement lies in that: in Step 1, when establishing the square super-element acoustic finite element model, assign material properties and set boundary conditions.

[0019] A further improvement lies in that: in Step 5, when screening the optimal dimension parameters, screen out the minimum value of the transmission loss of all models within the target frequency band, compare the maximum value among the minimum values, and the corresponding set of model dimensions is the optimal dimension parameters.

[0020] The beneficial effects of the present invention are as follows: The present invention forms a sound barrier by superimposing square super-elements distributed in an array, and partitions a winding channel inside the space winding box through a partition. The square super-element structure includes two parts, an outer square ring winding area and a central ventilation open area. It is not only simple to manufacture, but also has good ventilation performance, and can ensure good sound insulation effect while ensuring that the ventilation performance meets the standard. In addition, this application also realizes the optimization of the noise reduction performance of the sound barrier through an automatic optimization design method. Using this optimization design method can greatly save the simulation calculation time, improve the design efficiency, and make it possible to select the optimal dimensions from a large number of geometric design parameters. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 is the front view of the space winding square super-element array in the first embodiment of the present invention;

[0023] Figure 2 is the three-dimensional structure schematic diagram of the square super-element in the first embodiment of the present invention;

[0024] Figure 3 is the side cross-sectional view of the square super-element in the first embodiment of the present invention;

[0025] Figure 4 It is the transmission loss (TL) curve graph of the spatial coiled channel, the middle square hole channel and the super element in the simulation calculation of the first embodiment of the present invention;

[0026] Figure 5 It is the schematic diagram of the sound pressure distribution and the local velocity streamline at four representative frequencies in the first embodiment of the present invention;

[0027] Figure 6 It is the schematic diagram of the optimization design method flow in the second embodiment of the present invention;

[0028] Figure 7 It is the schematic diagram for comparing the transmission loss curves of the optimized super element and the reference super element in the second embodiment of the present invention;

[0029] Figure 8 It is the schematic diagram of the dimension marking for the modeling of the square super element in the second embodiment of the present invention.

[0030] Figure 9 It is the schematic diagram of the structures of the Type I unit and the Type II unit constructed in the third embodiment of the present invention;

[0031] Figure 10 It is the schematic diagram of the transmission loss curves of the Type I unit and the Type II unit in the third embodiment of the present invention.

[0032] Wherein: 1. Square super element; 2. Spatial coiled box; 3. Square frame; 4. Partition board; 5. Coiled channel. Specific implementation manners

[0033] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0034] Embodiment 1

[0035] Refer to Figure 1 , Figure 2 , Figure 3, this embodiment provides a sound barrier based on a spatially coiled square supercell array. The sound barrier is composed of several square supercells 1 designed to be square-shaped and surrounded. The several groups of square supercells 1 are arrayed and stacked to form a complete sound barrier. The square supercell 1 is designed to be square-shaped and surrounded by four groups of spatially coiled boxes 2. The spatially coiled box 2 includes a square frame 3 and a partition 4 fixed inside the square frame 3. The front and rear sides of the square frame 3 are designed to be open. The partitions 4 are staggered inside the square frame 3 to form a coiled channel 5. In this embodiment, the side length of the square supercell 1 is 80 mm, the thickness of the square supercell 1 is 40 mm, the thickness of the partition 4 is 1 mm, the thickness of the coiled channel 5 is 8 mm, and the thickness of the square supercell 1 is equal to the sum of the total thickness of the partitions 4 and the total thickness of the coiled channel 5.

[0036] The resonance unit formed by the spatially coiled box 2 can greatly reduce the thickness required for the sound barrier at low frequencies. When sound waves pass through it, it can generate a complete 2π phase delay within a distance much smaller than the wavelength of the sound wave, and the phase delay can be freely controlled by adjusting the structural parameters. The coiled channel 5 only allows sound waves that meet its resonance frequency to pass through completely, so the corresponding spectrum is discrete. There is a square hole 6 surrounded by four groups of spatially coiled boxes 2 in the middle position of the square supercell 1, and the square hole 6 is used for air flow to pass through. The square hole channel in the middle of the square supercell 1 allows sound waves of any frequency to pass through to achieve full transmission, so it presents a continuous spectrum. The supercell structure of this embodiment utilizes the coupling between the discrete state and the continuous state constructed by the two to achieve a Fano-like resonance.

[0037] The height of the partition 4 is less than the height of the square frame 3. Three of the outer walls of the partition 4 are fixedly connected to the inner wall of the square frame 3, and an empty groove is formed between the other outer wall and the square frame 3. The height of the coiled channel 5 is greater than the height of the partition 4, and the coiled channel 5 is connected to the empty groove to allow sound waves to pass through.

[0038] In this embodiment, there are a total of seven groups of partitions 4. Four of the seven groups of partitions 4 are fixed to one side inside the square frame 3, and the other three groups of partitions 4 are fixed to the other side inside the square frame 3. The four groups of partitions 5 on one side inside the square frame 3 are staggered with the four groups of partitions 5 on the other side inside the square frame 3.

[0039] The seven groups of partitions 4 divide the inside of the square frame 3 into six groups of coiled channels 5, and the six groups of coiled channels 5 are mirror-symmetrically distributed with the partition 4 in the middle position inside the square frame 3 as the center line.

[0040] In this embodiment, the square supercell 1 is studied by COMSOL Multiphysics software to verify the effectiveness of the design. As Figure 4The figures respectively show the transmission loss (TL) curves of the simulated spatial coiled channel, the middle square-hole channel, and the supercell. Whether it is the discrete state of the spatial coiled structure or the continuous state of the hollow square-hole structure. As Figure 4 shown in Figure a in Figure 4 , the corresponding transmission loss curves are all symmetric linear types. Only the resonance point corresponding to the spatial coiled channel appears at 498 Hz, and the transmission loss at the resonance frequency is almost zero, showing full transmission. Only the hollow square-hole shows full transmission at any frequency. However, for the combined coupled structure, i.e., the supercell, its transmission loss curve is no longer a simple superposition of the two. Due to the existence of the phase difference between the discrete state and the continuous state, the transmission loss curve is no longer symmetric. As Figure 4 shown in Figure b in

[0041] , a Fano-like resonance is achieved. Such an asymmetric resonance will have two anti-resonance points after the resonance frequency of full transmission, located at 536 Hz and 934 Hz respectively, and the corresponding transmission losses are as high as 50 dB and 74 dB. The sound wave almost shows full reflection at the anti-resonance points, thus achieving the purpose of noise reduction. It should be noted that according to the mechanical analogy of Fano resonance, the position of the transmission peak in Fano resonance will have a red shift compared to the resonance point position of the spatial coiled structure itself. For example, in this embodiment, the resonance point of the coiled channel 5 itself appears at 498 Hz, while the full transmission peak of this supercell appears at 468 Hz, and the resonance frequency has a 6.0% shift. Figure 4 The numerical simulation results in Figure b in

[0041] show that in the frequency band of 514 - 963 Hz (defined as the corresponding noise reduction frequency band), the transmission loss of this supercell is greater than 8 dB, and the maximum can reach 74 dB.

[0041] To more intuitively highlight the noise reduction effect of this supercell, four representative frequencies are selected: 500 Hz, 536 Hz, 700 Hz, and 934 Hz. The sound pressure field and local velocity streamline distributions of the cross-sections at each frequency are obtained through numerical simulation. As Figure 5 shown, at the peak frequencies of 536 Hz and 934 Hz, the sound pressure amplitude passing through the supercell decreases significantly, and a completely silent area (sound pressure almost 0) appears at its rear side. Due to the strong coupling effect between the spatial coiled structure and the square-hole structure, the radiation in the far field is weakened. Between the two peak frequencies (700 Hz), the simulation results show a similar pattern to that at the peak frequencies, that is, the sound pressure is significantly reduced. This indicates that the sound insulation performance of this supercell is not only limited to the two peak frequencies, but is still effective within the frequency range between them. Outside the two peak frequencies (500 Hz), the sound field shows a completely different pattern. Although the pressure amplitude decreases, the streamline parallel to the waveguide shows a large amount of sound energy leakage, and the noise reduction effect is poor.

[0042] Example Two

[0043] In this embodiment, taking the noise reduction application background of rail transit as an example, the structural dimensions of the sound barrier super unit are optimized. The noises generated during the operation of the train mainly include pantograph-catenary noise, aerodynamic noise, wheel-rail noise, electrical noise, auxiliary equipment noise, and structural noise, etc. Among them, the wheel-rail noise is the main sound source radiating noise to the outside. According to the measured wheel-rail noise spectrum of urban rail transit, the sound energy is mainly concentrated in the frequency band of 500 - 1000 Hz. This frequency band is used as the frequency design control range of the super unit, and the structural dimensions of the super unit (including the outer side length L, the inner side length l, and the thickness d 3 ) are optimized to find the best structural parameters that can meet the actual application requirements. The optimization goal is to find a set of optimal structural parameters within the preset parameter range so that the minimum value (the valley between the two peaks) of the transmission loss reaches the maximum within the target noise reduction frequency band of 500 - 1000 Hz. The preset parameter range is shown in Table 1 below. L is the side length of the square super unit 1, l is the thickness of the square super unit 1, w is the thickness of the partition, d 1 、d 2 and d 3 are all the thicknesses of the coiled channel 5, and the step size for each value is 1 mm. It should be noted that the value range of the parameter l is not independent but depends on the parameter L of the same model to prevent problems such as model errors and excessive or too small ventilation area.

[0044] Table 1 Preset range table of structural parameters of the square super unit

[0045]

[0046] See Figure 6 , this embodiment provides an optimization design method for a sound barrier based on an array of spatially coiled square super units, including the following steps:

[0047] Step 1: Define the global parameters L, l, w, d 1 、d 2 and d 3 in the COMSOL software. When modeling in COMSOL, assign values to parameters such as the side length and thickness of the three-dimensional model. As Figure 8 shown, where L is the outer side length of the square super unit 1, l is the inner side length of the square super unit 1, w is the thickness of the partition 4, d 1 is the thickness of the first group of coiled channels 5 from left to right, d 2 is the thickness of the second group of coiled channels 5 from left to right, d 3It is the thickness of the third set of coiled channels 5 from left to right. An acoustic finite element model of the square super element 1 is established using a model developer, and a frequency-domain study calculation is run to solve. During the modeling process, material properties are assigned and port boundary conditions are set to simulate the actual situation of the sound barrier. The material property of the acoustic finite element model is air, and the boundary condition is a hard sound field boundary. According to the solution calculation results, a octave band transmission loss curve between the incident and receiving ports, that is, the sound insulation amount, is drawn, which is calculated from the sound power at the waveguide inlet and outlet in the software. At the same time, the solution calculation data is exported for subsequent screening work;

[0048] Step 2: Use the APP developer module built into COMSOL software to create a new method for frequency-domain study calculation and result data export code in the method branch. The code snippet is extracted from the model developer in Step 1. Return to the model developer module and add a call to this method;

[0049] There are two specific operation methods: The first is to go to the "Development Tools" tab and then click Record Method; then, perform a series of complete operations in the model developer until the "Stop Recording" button is clicked; the relevant code will be saved to the new method. The second is to right-click on the "Study" branch in the model tree, and you will see a submenu for copying the code to the clipboard, and one of the options is Run; select this option to copy the code snippet for running to the clipboard; go to the method editor and paste to view the code, and the code extraction for result data export is the same as above;

[0050] Step 3: Enter COMSOL commands in the Windows command prompt CMD to traverse and modify parameters based on a loop statement. The modification range is the preset parameter range in Table 1 (the preset parameter range is roughly determined by manual trial calculation). For the arguments related to parameter modification in COMSOL commands, such as "-pname" and "-plist", etc., the specific usage method can refer to the COMSOL command part in the "COMSOL Multiphysics Reference Manual", and call the new method created in Step 2 to complete the model calculation after modifying the parameters once, obtaining result data, including a new transmission loss curve and calculation data. The new transmission loss curve is also the final calculated data, and this curve is drawn from this data. Subsequent screening is also performed on such data;

[0051] Step 4: The externally written program for traversing parameters is implemented through loop statements to traverse the code program of parameter values, so as to call CMD and implement the loop to modify the input COMSOL command string multiple times (the string in CMD, the meaning of the instruction remains unchanged, only the parameter values in the string are modified), traverse all dimension parameters within the preset range, and all dimension parameters are shown in Table 1. Repeat Step 3, and calculate and export the transmission loss result data corresponding to all models within the preset parameter range in turn (the transmission loss curve (continuous curve) of the model constructed by each group of parameters is drawn from the corresponding solution data (discrete points), and there is no relationship between the curves);

[0052] The externally written program will modify the parameter values in the command string multiple times, traverse the parameters, and export a set of calculation data each time;

[0053] Step 5: Use the screening program to determine the optimal dimension parameters. The working principle of the screening program is as follows: Traverse all the calculation result data in Step 4 and screen out the combination of dimension parameters that maximizes the average transmission loss of all models within the target frequency band, and use it as the optimal dimension parameters (the maximization of transmission loss is determined by the valley value of the transmission loss within the target frequency band. Screening is to find the minimum value in each group of data and compare the sizes of these minimum values. The parameter corresponding to the largest of these minimum values is the optimal parameter. The screening program is a process of finding the minimum and maximum values).

[0054] Step 3 of this embodiment is carried out in CMD (multiple modifications cannot be directly performed), which is the original modified string. Step 4 is written in another code editor to modify the string in CMD in Step 3 (the code editor is not specified, and VS Cold is used in this embodiment), so two steps are written.

[0055] Through the calculation of the above optimization design method, the optimal parameter supercell model with an outer side length L = 78 mm, an inner side length l = 34 mm, and a thickness d 3 = 13 mm is finally determined. Its simulation results are as shown by the solid line in Figure 7 compared with the reference supercell (dotted line). The optimized supercell has obvious improvements in both the noise reduction frequency band width and the sound insulation amount. Within the entire target noise reduction frequency band, the minimum value of the transmission loss after optimization can reach 11 dB, the average value is 14 dB, and the actual noise reduction frequency band where the transmission loss is greater than 11 dB is 495 - 1063 Hz. In addition, the total thickness t of the optimized supercell, that is, the thickness of the sound barrier, is a deep sub-wavelength size of only 65 mm, about λ / 12, where λ is the wavelength corresponding to the frequency 436 Hz at the first resonance point.

[0056] Example 3

[0057] According to the characteristics of acoustic Fano resonance, the square super unit 1 structures with different structural parameters have different corresponding noise reduction frequency bands. By using a certain combination of square super units 1 with multiple different parameters, the noise reduction frequency band can be widened to reach the target frequency band of 500-1750 Hz. The square super unit 1 with optimized parameters for wheel-rail noise in the frequency band of 500-1000 Hz in Example 2 is now used as the main super unit. According to the characteristics of the noise reduction frequency band of the main super unit, the parameter optimization method in Example 2 is still used to select an auxiliary super unit that can make up for the insufficient noise reduction effect. The specific structural parameters of the main super unit and the auxiliary super unit required to construct the ultra-wideband sound barrier are shown in Table 2 below. The transmission loss curves of the main and auxiliary super units in the frequency range of 200-2000 Hz are obtained through simulation calculation.

[0058] Table 2 Structural parameters of main super unit and auxiliary super unit (unit: mm)

[0059]

[0060] In the process of auxiliary super unit parameter optimization, it is important to note that the resonance point frequencies of the two super units should not be too close, otherwise the new structure composed of the two will resonate within the target noise reduction frequency range. At this time, a large number of sound waves near the resonance frequency of the structure will pass through, which is very unfavorable for the ultra-wideband noise reduction of the sound barrier.

[0061] In order to avoid multiple resonance points of the main super unit and the auxiliary super unit appearing in the target noise reduction frequency band, the two super units are arranged separately, that is, the first layer of the sound barrier only uses the main super unit, and the second layer only uses the auxiliary super unit. The combined structural unit of the double-layer sound barrier constructed by these two super units, such as Figure 9 As shown in , there are two types: the first type is a combination of four main super units as the first layer and nine auxiliary super units as the second layer, denoted as type I unit, such as Figure 9 The dotted box part shown in part (a) of the figure has a center distance of 70 mm between layers. The second type is a combination of a main super unit and an auxiliary super unit, which is recorded as a type II unit. Figure 9 In the dotted box part shown in part (b), the auxiliary super unit is embedded in the outer embedded plate of the same thickness, the centers of the main and auxiliary super units are located on the same normal line and the center distance between the layers is 70 mm.

[0062] In the pressure acoustics module, acoustic models of type I and type II units are established respectively, and the two are placed in the corresponding rectangular waveguides. A plane wave is input into the acoustic wave excitation port, and the transmission loss curves are obtained by solving, as shown in the figure. Figure 10 As shown in parts (a) and (b) of FIG.

[0063] Overall, within the entire target frequency range, the double-layer combined unit exhibits ultra-wideband noise reduction performance. For the Type-I unit, there are many mutation values in the transmission loss curve, especially in the high-frequency range. However, in the entire frequency band of 500 - 1750 Hz, the sound insulation amount can basically reach 10 dB or more, and the average sound insulation amount is 20.5 dB, achieving ultra-wideband and efficient noise reduction effects. Only near 700 Hz and 1000 Hz, completely sound transmission windows are opened. Since the frequency range is extremely narrow, in fact, the influence of this resonance on the noise reduction effect of the entire frequency band is very small. For the Type-II unit, the transmission loss curve within the target frequency range of 500 - 1750 Hz is relatively smooth. Except that the sound insulation amount in the frequency band of 600 - 700 Hz is relatively small, which is 5 - 10 dB, the sound insulation in the remaining frequency bands can reach more than 10 dB, and the average sound insulation amount is 21.5 dB. Moreover, there is no complete sound transmission in the ultra-wide frequency band of 200 - 2000 Hz, maintaining the coherence of the high-efficiency noise reduction frequency range, indicating that this arrangement and combination method effectively weakens the adverse effects of the resonance points of the two original super-units.

[0064] For the double-layer sound barrier designed in this Embodiment 3, whether it is the Type-I unit or the Type-II unit, ultra-wideband and high-efficiency noise reduction in the target frequency band of 500 - 1750 Hz is achieved, and the average value of the transmission loss in this frequency range exceeds 20 dB.

[0065] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for optimizing the design of a sound barrier of a spatially coiled square super unit array, characterized in that: The sound barrier comprises a square super unit (1), wherein the square super unit (1) is provided with a plurality of groups and is distributed in an array, wherein the square super unit (1) is designed in a square surround and is surrounded by four groups of space winding boxes (2), wherein the space winding boxes (2) comprise a square frame (3) and a partition (4) fixed inside the square frame (3), wherein the front and rear sides of the square frame (3) are designed to be open, wherein the partition (4) is staggeredly distributed inside the square frame (3) and forms a winding channel (5), wherein the height of the partition (4) is less than the height of the square frame (3), and the height of the winding channel (5) is greater than the height of the partition (4), wherein the space winding box (2) comprises ... space winding box (2) comprises a square frame (3) and a partition (4) fixed inside the square frame (3), wherein the space winding box (2) comprises a square frame (3) and a partition (4) fixed inside the square frame (3), wherein the space winding box (2) comprises a square frame (3) and a partition (4) fixed inside the square frame (3), wherein the space winding box (2) comprises a square frame (3) and a partition (4) fixed inside the square frame (3), wherein the space winding box (2) comprises a square frame (3) and a partition (4) fixed inside the square frame (3), wherein the space winding box (2) comprises a square frame (3) and a partition (4) fixed inside the square frame (3), wherein the space winding box (2) comprises a square frame (3 A square hole formed by four groups of space winding boxes (2) is provided in the middle of the square super unit (1) for airflow to pass through. The partition plates (4) are provided in seven groups. Four of the seven groups of partition plates (4) are fixed on one side of the inside of the square frame (3), and the other three groups of partition plates (4) are fixed on the other side of the inside of the square frame (3). Six groups of winding channels (5) are provided. The six groups of winding channels (5) are distributed in a mirror-symmetrical manner with the partition plate (4) in the middle of the inside of the square frame (3) as the center line. The thickness of the square super unit (1) is equal to the sum of the total thickness of the partition plates (4) and the total thickness of the winding channels (5). The optimization design method comprises the following steps: Step 1: Define global parameters in COMSOL software, establish an acoustic finite element model of the square super unit (1), and run a frequency domain study calculation to solve the problem. Draw a transmission loss curve based on the solution calculation results, and export the solution calculation data. Step 2: Use the APP Builder module that comes with the COMSOL software to create a method for frequency domain study calculations and result data export code in the method branch, return to the Model Builder module, and add a call to this method; Step 3: Enter the COMSOL command in the Windows command prompt CMD to modify the model parameters, and call the method created in step 2 to complete the model calculation after the modified parameters to obtain the result data; Step 4: Write a parameter traversal program externally to call CMD and implement multiple cycles to modify the input COMSOL command string, traverse all dimensional parameters within the preset range, repeat step 3, and calculate and export the transmission loss result data corresponding to all models within the preset parameter range in turn; Step 5: Use the screening program to determine the optimal size parameters, traverse all the calculation result data in step 4 and screen out the size parameter combination that maximizes the average transmission loss of all models in the target frequency band, and use it as the optimal size parameter.

2. The optimization design method of a sound barrier of a spatially coiled square super unit array according to claim 1 is characterized in that: In the step 1, when establishing the acoustic finite element model of the square super unit (1), material properties are assigned and boundary conditions are set.

3. The optimization design method of a sound barrier of a spatially coiled square super unit array according to claim 1 is characterized in that: In the step 5, when selecting the optimal size parameters, the lowest value of the transmission loss of all models in the target frequency band is selected, and the maximum value among the lowest values ​​is compared, and the corresponding set of model sizes is the optimal size parameters.

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