A method for analyzing vibration and noise characteristics of a subway river-crossing tunnel

Abstract

The application provides a subway river-crossing tunnel vibration noise characteristic analysis method, comprising the following steps: S1, establishing a structure finite element model according to the transverse and longitudinal sections of the river-crossing tunnel, including a tunnel-soil finite element model and a sleeper-rail-wheel finite element model; S2, obtaining a wheel-rail roughness model, specifically comprising: S21, coupling the two finite element models to obtain a frequency domain coupling model based on a frequency domain analysis method, and calculating the vibration admittance at the driving point of the rail under the action of the unit force; S22, coupling the two finite element models to obtain a power flow coupling model based on a power flow method, and calculating the wheel-rail force generated by the wheel on the track and the structure response; S23, using the vibration admittance, the wheel-rail force and the structure response obtained in S2, combining the track structure vibration response tested on site to back-calculate the wheel-rail roughness, and obtaining the wheel-rail roughness model; through back-calculation to obtain the wheel-rail roughness spectrum, more accurate vibration source information is obtained, and the accuracy and confidence of the numerical simulation model are improved.

Description

Technical Field

[0001] This invention relates to the field of transportation technology, and more specifically to a method for analyzing the vibration and noise characteristics of subway river-crossing tunnels. Background Technology

[0002] The development of urban rail transit has brought speed and convenience to travel, but the environmental vibration and noise caused by the interaction between the wheel and rail structures cannot be ignored. When trains pass through river-crossing tunnels, vibration and noise are gradually transmitted into the water through the structure, causing a significant impact on the lives of aquatic organisms. With the rapid increase in the number and scale of underwater projects, underwater noise poses a serious threat to the habitats of aquatic species. The cumulative effect of continuous noise reduces their alertness to predators and ships, damaging the ecological environment of marine life. The vibration and noise generated by trains passing through river-crossing tunnels is one such example.

[0003] Current research on vehicle-induced track vibration and noise primarily relies on air as the propagation medium. Finite element models are established to calculate aerodynamic noise in areas such as wheels and rails. For example, Chinese patent application number 2019110196552 calculates wheel-rail interaction forces based on the vibration admittance and combined roughness of high-speed railway wheels, rails, and wheel-rail systems. A joint prediction model for wheel-track vibration and noise is constructed based on fluid-structure interaction, and the vibration noise of wheels, rails, and track slabs is predicted using this model. The aerodynamic pressure within the flow field is obtained using a fluid domain model of the flow field in the wheel-rail region, and the aerodynamic noise in the wheel-rail region is simulated based on this pressure. Finally, based on the vibration noise of wheels, rails, and track slabs, and the aerodynamic noise in the wheel-rail region, near-field and far-field noise in the wheel-rail region are analyzed using fluid-structure interaction theory.

[0004] In the vibration and noise analysis of the Chezhi River-Crossing Tunnel, the reference sound pressure needs to be modified according to the different propagation media. Furthermore, the source of underwater noise is the vibration of the soil at the water-soil interface; the vibration of the underlying soil layer cannot directly radiate underwater noise. Therefore, it is necessary to distinguish this from traditional vibration and noise analysis during finite element modeling. In summary, there is still a lack of effective methods to analyze the vibration and noise characteristics of the Chezhi River-Crossing Tunnel. Summary of the Invention

[0005] The purpose of this invention is to disclose a method for analyzing the vibration and noise characteristics of subway river-crossing tunnels, which solves the problem that traditional noise analysis methods have low accuracy and are affected by many factors, making it difficult to accurately analyze the noise characteristics of subway river-crossing tunnels.

[0006] To achieve the above objectives, this invention provides a method for analyzing the vibration and noise characteristics of subway river-crossing tunnels, comprising the following steps:

[0007] S1. Based on the cross-sections and longitudinal sections of the river-crossing tunnel, a structural finite element model is established, including a tunnel-soil finite element model and a sleeper-rail-wheel finite element model.

[0008] S2, obtaining the wheel-rail roughness model, specifically includes the following sub-steps:

[0009] S21. A frequency domain coupled model is obtained by coupling two finite element models based on the frequency domain analysis method, and the vibration admittance at the rail drive point under the action of unit force is calculated.

[0010] S22, based on the power flow method, two finite element models are coupled to obtain a power flow coupled model, and the wheel-rail force and structural response generated by the wheel on the track are calculated;

[0011] S23, using the vibration admittance, wheel-rail force, and structural response obtained in S2, combined with the track structure vibration response tested in the field, the wheel-rail roughness is inferred to obtain the wheel-rail roughness model.

[0012] S3. Based on the wheel-rail roughness model obtained in step S2, calculate the vibration response of the tunnel-soil coupled system under the action of a single wheelset. On this basis, analyze and obtain the structural acceleration level spectrum, and save the analysis results of the coupling of the two finite element models.

[0013] S4. Based on the analysis results in step S3, establish an acoustic finite element model and sound field points, set acoustic model parameters, import the vibration response results of the tunnel-soil coupling system in step S3 as the boundary conditions of the acoustic model, calculate underwater vibration noise based on acoustic-vibration coupling analysis, and obtain an underwater vibration noise model.

[0014] S5. Based on the underwater vibration and noise model obtained in step S4, the sound pressure at the field point calculated by the acoustic model is derived, the 1 / 3 octave band sound pressure level is calculated, the sound pressure spatial distribution cloud map is plotted using MATLAB and the noise propagation law is analyzed, and the characteristics of the vibration and noise of the subway river-crossing tunnel and its impact on underwater organisms are evaluated in combination with the underwater biological hearing threshold curve.

[0015] The evaluation method in step S5 is as follows:

[0016] The time-frequency curve of the sound field points was obtained by performing short-time Fourier transform using IZotope software, and the dominant frequency range of vibration noise during the subway passage time was determined.

[0017] The underwater vibration noise of the tunnel and the hearing threshold of underwater organisms were compared in different frequency bands at different locations within the spatial sound field.

[0018] As a further improvement of the present invention, the connection between the rail and the sleeper in step S1 is simulated by a three-way spring damping unit.

[0019] The boundary element method is used to simulate the cut-off location.

[0020] As a further improvement of the present invention, in step S2, a single-wheel model is used to perform vehicle-tunnel-soil coupled vibration response analysis to ignore the influence of the vehicle's secondary suspension.

[0021] As a further improvement of the present invention, in step S22, when calculating the structural response, one wheel is taken as the driving wheel and the other wheels are taken as the passive wheels. The wheel-rail interaction force is applied at the position of the driving wheel, and the passive wheels are connected to the rail by a mass unit through a spring.

[0022] As a further improvement of the present invention, in step S23, the on-site structural test requires at least three acceleration sensors to be installed at different locations on the tunnel, including: a lateral acceleration sensor, a vertical acceleration sensor and a longitudinal acceleration sensor. The measured time-domain response is converted to the frequency domain through a fast Fourier transform and compared with the numerical simulation results at various frequency points, thereby obtaining the wheel-rail roughness spectrum.

[0023] As a further improvement of the present invention, in step S3, based on the frequency domain coupling model, each wheel is treated as an active wheel, and the moving roughness model is adopted to consider the influence of different wheelset positions. Different active wheel conditions are regarded as incoherent vibration sources and superimposed to obtain the structural response under the action of multiple wheelsets.

[0024] As a further improvement of the present invention, the structural acceleration level spectrum obtained by simulation analysis in step S3 is fitted with the acceleration level spectrum of the measured data in step S2.

[0025] If the frequency domain coupling model matches the measured results well near the peak frequency and is generally consistent, it indicates that the frequency domain coupling model accurately simulates the vibration of the train during operation.

[0026] If the fit is poor, the validity of the finite element model needs to be re-examined.

[0027] As a further improvement of the present invention, in step S4, the acoustic-structure coupling surface mesh in the acoustic model is directly extracted from the outer surface mesh of the structure to maintain consistency, and is extended to the normal direction of the outer surface of the structure to generate a convex surface to generate an acoustic finite element mesh, and the infinite element method is used to satisfy the Sommerfeld boundary conditions in the acoustic model.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] (1) Unlike the scheme of calculating the wheel-rail interaction force by using the vibration admittance of the wheel and the wheel-rail and the joint roughness, and then constructing a model to calculate vibration noise, this method can obtain the wheel-rail roughness spectrum by calculating the wheel-rail force and structural response of the coupled vibration model when the roughness is unknown, and using the track structure vibration response tested in the field as a reference. This method can obtain vibration source information more accurately and improve the accuracy and confidence of the numerical simulation model.

[0030] (2) The finite element model simulates the connection between the rail and the sleeper through the triaxial spring damping element, which improves the reliability of the calculation results and is closer to the actual working conditions. In the finite element modeling process, the boundary element simulation method is used at the truncation position of the model, which effectively eliminates the reflection phenomenon of vibration waves at the truncation boundary and improves the efficiency and accuracy of finite element calculation.

[0031] (3) By using power flow theory and frequency domain coupled vibration analysis, the vibration and sound radiation characteristics can be quickly determined, and the computational efficiency is higher than that of the time domain nonlinear coupled model.

[0032] (4) Compared with traditional vibration and noise analysis, this invention provides an analysis method for the vibration and noise characteristics of river-crossing tunnels in water, which is innovative and unique;

[0033] (5) The established finite element model is a vehicle-tunnel-soil coupled model. Compared with the vehicle-tunnel coupled model, the influence of soil on the structural vibration response is considered, making the calculation results more consistent with the measured data.

[0034] (6) Since the wave speed generated by vibration in the track is much higher than the vehicle speed in rail transit, the wheel-rail interaction model adopts the moving roughness model in the frequency domain analysis, assuming that the wheel is stationary, which can effectively reduce the error caused by the Doppler effect. Attached Figure Description

[0035] Figure 1 This is a flowchart illustrating the vibration and noise characteristics analysis method for a subway river-crossing tunnel according to the present invention.

[0036] Figure 2 This is a diagram of the tunnel-soil finite element model in the vibration and noise characteristics analysis method for subway river-crossing tunnels of the present invention;

[0037] Figure 3 This is a schematic diagram of the measured-simulated acceleration level spectrum in the vibration and noise characteristic analysis method for subway river-crossing tunnels of the present invention;

[0038] Figure 4 This is a schematic diagram of the sound pressure spectrum at various points in the vibration and noise characteristics analysis method for a subway river-crossing tunnel according to the present invention.

[0039] In the figure: 1. Artificial boundary; 2. Soil mass; 3. Tunnel. DETAILED DESCRIPTION

[0040] The present invention will be described in detail below with reference to the respective embodiments shown in the accompanying drawings. It should be noted that these embodiments are not intended to limit the present invention, and all equivalent transformations or substitutions in functions, methods or structures made by those of ordinary skill in the art based on these embodiments shall fall within the protection scope of the present invention.

[0041] For the convenience of understanding the present invention, the present invention will be described more comprehensively below with reference to the related accompanying drawings. The preferred embodiments of the present invention are presented in the accompanying drawings. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive to understand.

[0042] Please refer to Figures 1 to 4 the shown specific embodiment of the method for analyzing vibration and noise characteristics of a metro river-crossing tunnel according to the present invention.

[0043] As shown in Figure 1 the figure, the present invention discloses a method for analyzing vibration and noise characteristics of a metro river-crossing tunnel, which is specifically as follows: S1, establishing a structural finite element model according to the cross section and longitudinal section of the river-crossing tunnel, including a tunnel-soil mass finite element model and a sleeper-rail-wheel finite element model;

[0044] S2, coupling the two finite element models based on a frequency domain analysis method to obtain a frequency domain coupling model, calculating the vibration admittance at the rail driving point under the action of unit force, coupling the two finite element models based on a power flow method and calculating the wheel-rail force and structural response generated by the wheels on the track, and back-calculating the wheel-rail roughness in combination with the field-tested vibration response of the track structure to obtain a wheel-rail roughness model;

[0045] S3, calculating the vibration response of the tunnel-soil mass coupling system under the action of a single wheelset according to the wheel-rail roughness model in step S2, analyzing on this basis to obtain the structural acceleration level frequency spectrum, and saving the analysis result of the finite element model;

[0046] S4, establishing an acoustic finite element model and sound field points according to the analysis result in step S3, setting parameters of the acoustic model, importing the vibration response calculation result in step S3 as the boundary condition of the acoustic model, and calculating underwater vibration and noise based on vibro-acoustic coupling analysis to obtain an underwater vibration and noise model;

[0047] In S5, the underwater vibration and noise model obtained in step S4 is used to derive the field point sound pressure calculated by the acoustic model, the 1 / 3-octave sound pressure level is calculated, the spatial distribution cloud map of sound pressure is drawn to analyze the noise propagation law, and the characteristics of vibration and noise of the metro river-crossing tunnel and its impact on underwater organisms are evaluated in combination with the hearing threshold curve of underwater organisms.

[0048] The method of the present invention can be used to analyze the vehicle-induced vibration and noise characteristics of a river-crossing tunnel, obtain the noise impact of the train on the river-crossing tunnel, and provide a theoretical basis for reducing the impact of vibration and noise on structures and underwater organisms.

[0049] In the following, taking a certain metro river-crossing tunnel structure as an example, the method of the present invention for analyzing vehicle-induced river-crossing tunnel is presented:

[0050] (1) Coupling two finite element models based on the frequency domain analysis method

[0051] Reference Figure 2 As shown, based on the two finite element models, functions such as Boolean operation, coordinate transformation, copying, and rotation are used to establish a complex and accurate train-tunnel-soil coupling model. For this project, geometric models including the soil, box culvert, cushion, sleeper, and artificial boundary are established first, all of which adopt the solid element Solid45, and meshing is performed after the geometric model is established. For the weight of the backfill part and water, the mass element Mass21 is adopted, and the mass elements are directly applied to the nodes without the need to establish a backfill part model and a water body model. The rail structure adopts the beam element Beam188, and the beam elements are directly added to the overall structure by importing the meshed cross-section, and connected through three-way spring damping elements. In terms of meshing, the element size needs to meet the requirement of 6 elements within the minimum wavelength, and the element size is gradually increased at positions far away from the vibration source to reduce the calculation time and improve efficiency while ensuring accuracy.

[0052] (2) Back-calculation of wheel-rail roughness

[0053] Two finite element models are coupled based on the frequency domain analysis method to obtain a frequency domain coupling model, and the vibration admittance at the rail driving point under the action of element force is calculated. The frequency domain coupling model is used to simulate and calculate the wheel-rail force generated by the train-tunnel-soil system on the track, with the calculation frequency interval set to 1Hz. In the frequency domain coupling model based on frequency domain analysis, each wheel is taken as the driving wheel one by one, the wheel-rail roughness model is adopted to consider the influence of different wheelset positions, and different driving wheel working conditions are regarded as incoherent vibration sources for superposition to obtain the structural response under the action of multiple wheelsets. Transverse acceleration sensors, vertical acceleration sensors and longitudinal acceleration sensors are arranged on the tunnel structure, the measured time-domain responses are converted to the frequency domain through fast Fourier transform, and compared with the numerical simulation results at each frequency point, so as to back-calculate and obtain the wheel-rail roughness spectrum.

[0054] The formula is as follows:

[0055] Admittance is the ratio of the steady-state response of a structure to the harmonic excitation force, which is also the reciprocal of the impedance. It is calculated as follows:

[0056] Suppose a single-degree-of-freedom system is subjected to a simple harmonic excitation force:

[0057] P(t) = P0e jωt

[0058] The steady-state response of the structure is:

[0059]

[0060] The admittance is then:

[0061]

[0062] in, It is a complex number. i and j are unit imaginary numbers, ω is the angular frequency, P0 is the initial force acting on the structure, c is the ratio of the damping force to the velocity, k is the structural stiffness coefficient, and m is the structural mass. It can be seen that the admittance is a complex function of the frequency, independent of the magnitude of the excitation force, and depends only on the characteristics of the structure itself (such as inertia, elasticity, and damping characteristics).

[0063] Wheel-rail force calculation formula:

[0064]

[0065] Where: R is the roughness amplitude corresponding to a certain wavelength at the corresponding vehicle speed and calculation frequency; α w The dynamic compliance of the wheel can be obtained from a simplified vehicle model. α c This refers to the dynamic flexibility of the wheel-rail contact spring, which can be obtained using the Hertz contact model; α r The dynamic compliance of the rail is obtained using the power flow method.

[0066] (3) Calculate the vibration response of the system using the roughness model.

[0067] Using the harmonic response analysis method, the vibration results of the structure are calculated under the action of continuous periodic load. In the coupled vibration model based on frequency domain analysis, each wheel is taken as the driving wheel in turn, and the other wheels are taken as the driven wheels. The structural vibration response under the action of different wheelsets is regarded as a nonlinear coherent vibration source. The structural vibration response under the action of multiple wheelsets is obtained through the superposition principle. On this basis, the structural acceleration level spectrum is analyzed and the analysis results of the coupling of two finite element models are saved. Figure 3 This is a simulation-measured acceleration spectrum diagram.

[0068] The structural acceleration level spectrum obtained from the simulation analysis in step S3 is fitted with the acceleration level spectrum of the measured data in step S2. If the agreement between the two results is high and consistent with the measured results near the peak frequency, it indicates that the frequency domain coupling model accurately simulates the vibration of the train during operation. If the agreement is poor, the validity of the finite element model needs to be rechecked.

[0069] (4) Establish an acoustic finite element model to analyze and calculate underwater vibration and noise.

[0070] The distribution of soil vibration noise in water was investigated, with water as the propagation medium and a sound velocity of 1300 m / s. The acoustic finite element method was used for modeling, and the infinite element method was employed to satisfy the Sommerfeld boundary conditions in the acoustic model. The structural response calculation results were imported into the acoustic model to calculate the radiated sound pressure. Sound pressure at different locations was calculated separately, ignoring the effect of phase difference, and the total sound pressure was obtained by superimposing incoherent sound sources. Based on the coordinates of the measuring points, field points were set along the outward normal direction at depths of 1 m, 2 m, 3 m, 5 m, and 10 m underwater. Furthermore, to calculate the spatial distribution characteristics, planar field points were set along the tunnel cross-section, with a height of 10 m, a width of 30 m, and a spacing of 2 m.

[0071] (5) Analyze the propagation law and evaluate the characteristics of vibration noise and its impact on underwater organisms.

[0072] The center frequency is determined as Based on the underwater vibration and noise model obtained in step S4, the sound pressure at the field point calculated by the acoustic model is derived, and the 1 / 3 octave band sound pressure level is calculated. One octave band is divided into three adjacent 1 / 3 octave bands, and the sound domain is divided into 30 1 / 3 octave bands. The sound pressure level spectrum diagram of the field point in the direction of the outer normal of the soil center is drawn, with distances from the water surface of 1m, 2m, 3m, 5m and 10m respectively. Figure 4 The sound pressure spectrum diagrams for each field point are generated. By plotting the spatial distribution cloud map of sound pressure and analyzing the noise propagation law, and combining this with the underwater biological hearing threshold curve, the characteristics of the vibration noise of the subway tunnel crossing the river and its impact on underwater organisms are evaluated. The evaluation method in step S5 is as follows: the time-frequency curve of the sound field point is obtained through short-time Fourier transform to determine the dominant frequency range of vibration noise during the subway passage period; the underwater vibration noise of the tunnel and the hearing threshold of underwater organisms are compared in frequency bands at different locations within the spatial sound field range to analyze its auditory impact on different underwater organisms. Sound pressure cloud maps are plotted based on the sound pressure values ​​within the planar field point to analyze the noise distribution patterns along the horizontal and vertical directions.

[0073] Based on the calculation results, a curve of total sound pressure level versus distance was obtained. Taking the Yangtze finless porpoise as an example, which belongs to the class Mammalia and order Cetacea, and referring to the US regulations on cetacean research, the permanent hearing threshold shift (183dB) and temporary hearing threshold shift (120dB) of low-frequency (LF) whales were compared with the total sound pressure level curve. If the two overlapped significantly, it would indicate that the impact on the auditory system of the finless porpoise would be significant.

[0074] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for analyzing the vibration and noise characteristics of a subway river-crossing tunnel, characterized in that, Includes the following steps: S1. Based on the cross-sections and longitudinal sections of the river-crossing tunnel, a structural finite element model is established, including a tunnel-soil finite element model and a sleeper-rail-wheel finite element model. S2, obtaining the wheel-rail roughness model, specifically includes the following sub-steps: S21. A frequency domain coupled model is obtained by coupling two finite element models based on the frequency domain analysis method, and the vibration admittance at the rail drive point under the action of unit force is calculated. S22, based on the power flow method, two finite element models are coupled to obtain a power flow coupled model, and the wheel-rail force and structural response generated by the wheel on the track are calculated; S23, using the vibration admittance, wheel-rail force, and structural response obtained in S2, combined with the track structure vibration response tested in the field, the wheel-rail roughness is inferred to obtain the wheel-rail roughness model. S3. Based on the wheel-rail roughness model obtained in step S2, calculate the vibration response of the tunnel-soil coupled system under the action of a single wheelset. On this basis, analyze and obtain the structural acceleration level spectrum, and save the analysis results of the coupling of the two finite element models. S4. Based on the analysis results in step S3, establish an acoustic finite element model and sound field points, set acoustic model parameters, import the vibration response results of the tunnel-soil coupling system in step S3 as the boundary conditions of the acoustic model, calculate underwater vibration noise based on acoustic-vibration coupling analysis, and obtain an underwater vibration noise model. S5. Based on the underwater vibration and noise model obtained in step S4, the sound pressure at the field point calculated by the acoustic model is derived, the 1 / 3 octave band sound pressure level is calculated, the sound pressure spatial distribution cloud map is plotted using MATLAB and the noise propagation law is analyzed, and the characteristics of the vibration and noise of the subway river-crossing tunnel and its impact on underwater organisms are evaluated in combination with the underwater biological hearing threshold curve. The evaluation method in step S5 is as follows: The time-frequency curve of the sound field points was obtained by performing short-time Fourier transform using IZotope software, and the dominant frequency range of vibration noise during the subway passage time was determined. The underwater vibration noise of the tunnel and the hearing threshold of underwater organisms were compared in different frequency bands at different locations within the spatial sound field.

2. The method for analyzing the vibration and noise characteristics of a subway river-crossing tunnel according to claim 1, characterized in that, In step S1, the connection between the rail and the sleeper is simulated using a three-way spring damping unit. The boundary element method is used to simulate the cut-off location.

3. The method for analyzing the vibration and noise characteristics of a subway river-crossing tunnel according to claim 1, characterized in that, In step S2, a single-wheel model is used to perform vehicle-tunnel-soil coupled vibration response analysis to ignore the influence of the vehicle's secondary suspension.

4. The method for analyzing the vibration and noise characteristics of a subway river-crossing tunnel according to claim 1, characterized in that, In step S22, when calculating the structural response, one wheel is taken as the driving wheel and the other wheels are taken as the passive wheels. The wheel-rail interaction force is applied at the position of the driving wheel, and the passive wheels are connected to the rail by a mass element through a spring.

5. The method for analyzing the vibration and noise characteristics of a subway river-crossing tunnel according to claim 1, characterized in that, In step S23, the on-site structural test requires at least three acceleration sensors to be installed at different locations on the tunnel, including: a lateral acceleration sensor, a vertical acceleration sensor, and a longitudinal acceleration sensor. The measured time-domain response is converted to the frequency domain through a fast Fourier transform and compared with the numerical simulation results at various frequency points, thereby obtaining the wheel-rail roughness spectrum.

6. The method for analyzing the vibration and noise characteristics of a subway river-crossing tunnel according to claim 4, characterized in that, In step S3, based on the frequency domain coupling model, each wheel is treated as an active wheel. The moving roughness model is adopted to consider the influence of different wheel pair positions. Different active wheel conditions are treated as incoherent vibration sources and superimposed to obtain the structural response under the action of multiple wheel pairs.

7. The method for analyzing the vibration and noise characteristics of a subway river-crossing tunnel according to claim 1, characterized in that, The structural acceleration level spectrum obtained from the simulation analysis in step S3 is fitted with the acceleration level spectrum of the measured data in step S2; If the frequency domain coupling model matches the measured results well near the peak frequency and is generally consistent, it indicates that the frequency domain coupling model accurately simulates the vibration of the train during operation. If the fit is poor, the validity of the finite element model needs to be re-examined.

8. The method for analyzing the vibration and noise characteristics of a subway river-crossing tunnel according to claim 1, characterized in that, In step S4, the acoustic-structure interaction surface mesh in the acoustic model is directly extracted from the outer surface mesh of the structure to maintain consistency, and is extended to the normal direction of the outer surface of the structure to generate a convex surface to generate an acoustic finite element mesh. The infinite element method is used to satisfy the Sommerfeld boundary conditions in the acoustic model.

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