Sound absorption layer performance simulation method for structural deformation and material parameter change under hydrostatic pressure

Abstract

The invention relates to a sound absorption layer performance simulation method for structural deformation and material parameter change under hydrostatic pressure. The method comprises the following steps: establishing a sound absorption layer geometric model and a sound propagation medium geometric model; a solid mechanics physical field and a pressure acoustics physical field are defined, boundary conditions are set, the sound absorption layer is the solid mechanics physical field, the sound propagation medium and an inner cavity of the sound absorption layer are the pressure acoustics physical field, and the coincidence boundary of the sound absorption layer and the sound propagation medium is a sound-solid coupling boundary; setting a deformation area, and transmitting a structural deformation calculation result of a solid mechanical domain under the action of hydrostatic pressure to an acoustic domain through a dynamic grid interface; mechanical parameters of the sound absorption layer material are coupled with the hydrostatic pressure; and carrying out mechanical deformation solution and acoustic solution in series to obtain a sound absorption performance result of the sound absorption layer. According to the method, physical and mechanical parameters such as modulus and Poisson's ratio of the sound absorption layer material are coupled with the hydrostatic pressure during simulation, so that simulation setting is closer to the actual situation, and the credibility of a simulation result is improved.

Description

Technical Field

[0001] This application relates to the field of underwater sound-absorbing layer performance simulation technology, and in particular to a method for simulating the performance of sound-absorbing layers under hydrostatic pressure by analyzing structural deformation and material parameter changes. Background Technology

[0002] Underwater sound-absorbing layer technology is a core technology for achieving acoustic stealth and noise control in the field of marine engineering. Existing solutions mostly use rubber-based materials to absorb and dissipate sound energy through viscoelastic losses. Current sound-absorbing layer technology can achieve complete absorption of mid-to-high frequency sound waves, but due to size-wavelength effects, achieving efficient low-frequency sound absorption performance with a relatively small sound-absorbing layer size presents a significant challenge. To achieve efficient low-frequency sound absorption with a smaller size, it is usually necessary to design a cavity structure within the sound-absorbing layer. Through the resonance and waveform conversion functions of the cavity structure, low-frequency sound absorption performance can be improved within a limited thickness.

[0003] As the working depth of marine structures continues to expand into the deep sea, the hydrostatic pressure of the deep sea brings enormous challenges to the design of sound-absorbing layers, mainly in the following aspects: Firstly, the matrix material constituting the sound-absorbing layer is mainly viscoelastic material such as rubber. The physical properties of the material, such as elastic modulus, density, porosity, etc., are pressure-sensitive. The propagation speed and attenuation characteristics of sound waves in the material are directly related to these material parameters. Pressure-induced parameter changes will destroy the theoretical basis of the original sound-absorbing design.

[0004] On the other hand, the low-frequency broadband sound absorption achieved by the sound-absorbing layer depends on special structural designs such as cavities and periodic structures. Under hydrostatic pressure, the geometry of the structure will change, which may cause the sound absorption mechanism to fail, the effective sound absorption frequency band to shift, and the sound absorption coefficient to decrease significantly.

[0005] Hydrostatic pressure resistant sound-absorbing layers can reduce the impact of hydrostatic pressure on the performance of sound-absorbing layers. However, designing high hydrostatic pressure resistant sound-absorbing layers first requires establishing an accurate simulation method for hydrostatic pressure resistant sound-absorbing layer performance. Currently, most sound-absorbing layer performance simulation designs are limited to simulating normal pressure conditions and do not comprehensively consider the impact of structural deformation and changes in material mechanical parameters on sound absorption performance under high hydrostatic pressure conditions.

[0006] The performance of sound-absorbing layers under hydrostatic pressure is usually analyzed using the finite element method. For example, if we take a hydrostatic sound-absorbing material with an elliptical cavity as the research object, we can use the finite element method to analyze the deformation of the sound-absorbing material under hydrostatic pressure, and then use the "moving mesh" module to directly apply the deformation results to the acoustic-structure interaction calculation, thereby realizing the simulation calculation of the sound absorption performance under hydrostatic pressure.

[0007] However, the above analysis method only considers the structural deformation caused by hydrostatic pressure, while ignoring the changes in physical property parameters of the sound-absorbing layer matrix material, such as modulus and Poisson's ratio. Therefore, the accuracy of the analysis results needs to be further improved. Consequently, existing simulation methods for sound-absorbing layer performance cannot accurately simulate the effects of deformation and changes in material physical property parameters under high hydrostatic pressure, leading to the problem of inaccurate prediction of the sound absorption performance of sound-absorbing layers under high hydrostatic pressure. Summary of the Invention

[0008] This application provides a method for simulating the performance of a sound-absorbing layer under hydrostatic pressure by assessing structural deformation and changes in material parameters. This method addresses the problem in related technologies where simulation methods for sound-absorbing layer performance cannot accurately simulate the effects of deformation and changes in material physical properties under high hydrostatic pressure, leading to inaccurate predictions of the sound absorption performance of the sound-absorbing layer under high hydrostatic pressure.

[0009] This application provides a method for simulating the performance of a sound-absorbing layer under hydrostatic pressure, involving structural deformation and changes in material parameters. The method includes: Establish the geometric model of the sound-absorbing layer and the geometric model of the sound propagation medium; Define the solid mechanical physical field and the pressure acoustic physical field, and set the boundary conditions, wherein the sound-absorbing layer is the solid mechanical physical field, the sound propagation medium and the internal cavity of the sound-absorbing layer are the pressure acoustic physical field, and the boundary of the sound-absorbing layer and the sound propagation medium is the sound-solid coupling boundary. A deformation region is set up, and the structural deformation calculation results of the solid mechanics domain under hydrostatic pressure are transferred to the acoustic domain through the dynamic mesh interface; The mechanical parameters of the sound-absorbing layer material are coupled with the magnitude of the hydrostatic pressure, and the mechanical parameters are obtained based on actual experimental tests. The mechanical deformation and acoustic solutions are performed in series to obtain the sound absorption performance results of the sound-absorbing layer.

[0010] In some embodiments, establishing a geometric model of the sound-absorbing layer and a geometric model of the sound propagation medium specifically includes: The sound-absorbing layer has a periodic sound-absorbing structure inside. One or more periodic sound-absorbing layer geometric models are established based on the calculation amount of the simulation model. A large sound-absorbing layer model or a full-size sound-absorbing layer model is simulated by setting boundary conditions. The sound propagation medium includes water, air, or a combination of both. The sound wave incident end of the sound-absorbing layer coincides with one end of the water medium segment, and the rigid backing end of the sound-absorbing layer coincides with one end of the water or air medium. A perfectly matched layer is provided to simulate an infinite domain.

[0011] In some embodiments: the sound-absorbing layer is defined as a solid mechanical physical field to obtain the deformation results under hydrostatic pressure, and a deformation region is set for mechanical calculation. In the mechanical calculation, the lower boundary of the sound-absorbing layer is defined as a fixed boundary, and a pressure load is applied to the upper boundary of the sound-absorbing layer to simulate hydrostatic pressure. The sound propagation medium and the sound-absorbing layer are defined as pressure acoustic physical fields. An incident sound field condition is added to the medium domain, and the sound wave propagation direction is pointed towards the sound-absorbing layer to simulate the incident sound wave. The boundary conditions on both sides of the geometric model of the sound-absorbing layer and the geometric model of the sound propagation medium are defined as periodic boundaries.

[0012] In some embodiments, a deformation region is defined, and the structural deformation calculation results of the solid mechanics domain under hydrostatic pressure are transferred to the acoustic domain through a dynamic mesh interface, specifically including: A deformation domain is set in the geometric model of the sound-absorbing layer. The deformation domain is selected as the acoustic calculation domain. After the mechanical deformation results are solved, the geometric model is reconstructed based on the deformation calculation results of the sound-absorbing layer structure, and then the acoustic calculation is performed. The structural deformation calculation results of the solid mechanical domain under hydrostatic pressure are transferred to the acoustic domain through the dynamic mesh interface. The acoustic domain directly uses the deformed geometric model to calculate the sound absorption performance, so that the structural deformation of the sound-absorbing layer is related to the acoustic performance of the sound-absorbing layer.

[0013] In some embodiments, the mechanical parameters include at least one of Young's modulus, Poisson's ratio, shear modulus, and bulk modulus.

[0014] In some embodiments, the method further includes: The geometric model of the sound-absorbing layer is meshed, and the mesh is refined in areas where the expected deformation is severe under hydrostatic pressure to avoid mesh distortion after large deformation affecting the calculation convergence. In addition, the mesh quality index is controlled to avoid high aspect ratio, small interior angle or twisted elements.

[0015] In some embodiments, mechanical deformation solutions and acoustic solutions are performed in series, specifically including: First, the structural deformation of the sound-absorbing layer under hydrostatic pressure is calculated using solid mechanical physics. The deformation results are then automatically transferred to the pressure acoustic physics as real-time input for acoustic calculations. In the same simulation model, the sound absorption is calculated directly based on the deformed geometry.

[0016] In some embodiments: the sound absorption performance of the sound-absorbing layer is obtained by formula The calculation yielded, where The sound absorption coefficient is... To reflect sound pressure, This is the incident sound pressure.

[0017] In some embodiments: after completing one series connection for mechanical deformation and acoustic solution, the mechanical deformation and acoustic solution are then performed again after coupling different mechanical parameters and hydrostatic pressure of the sound-absorbing layer material.

[0018] In some embodiments, the sound-absorbing layer includes a rigid backing layer and a rubber layer, wherein the rubber layer is applied to the rigid backing layer and has a plurality of periodic cavities.

[0019] The beneficial effects of the technical solution provided in this application include: This application provides a simulation method for the performance of a sound-absorbing layer under hydrostatic pressure, considering structural deformation and material parameter changes. The method first establishes a geometric model of the sound-absorbing layer and a geometric model of the sound propagation medium. Then, it defines a solid mechanical field and a pressure acoustic field, setting boundary conditions. The sound-absorbing layer is defined as the solid mechanical field, while the sound propagation medium and the internal cavity of the sound-absorbing layer are defined as the pressure acoustic field. The boundary where the sound-absorbing layer and the sound propagation medium coincide is defined as the acoustic-solid coupling boundary. Next, a deformation region is set, and the structural deformation calculation results from the solid mechanical domain under hydrostatic pressure are transferred to the acoustic domain through a dynamic mesh interface. Then, the mechanical parameters of the sound-absorbing layer material are coupled with the magnitude of the hydrostatic pressure, with the mechanical parameters obtained from actual experimental tests. Finally, the mechanical deformation solution and the acoustic solution are performed in series to obtain the sound absorption performance results of the sound-absorbing layer.

[0020] Therefore, the sound-absorbing layer performance simulation method of this application is based on the mechanical parameters of the sound-absorbing layer material under different hydrostatic pressures obtained from experimental tests, such as modulus and Poisson's ratio. During simulation, the physical and mechanical parameters of the sound-absorbing layer material, such as modulus and Poisson's ratio, are coupled with the magnitude of hydrostatic pressure to simulate the changes in the material's physical properties and mechanical parameters with the magnitude of hydrostatic pressure. This makes the simulation settings closer to actual conditions and improves the reliability of the simulation results. By setting deformation regions and serial calculation steps, the deformation calculation under hydrostatic pressure is coupled with the acoustic calculation in a single model. Furthermore, considering the normal deformation of the sound-absorbing layer's side surface and the changes in the material's mechanical parameters under hydrostatic pressure, the reliability and computational efficiency of the sound absorption performance simulation under varying hydrostatic pressure are improved. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the geometric model of the sound-absorbing layer and the geometric model of the sound propagation medium in an embodiment of this application; Figure 2This is a flowchart illustrating the simulation method for the performance of the sound-absorbing layer under hydrostatic pressure, considering structural deformation and parameter changes, according to an embodiment of this application. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] This application provides a method for simulating the performance of a sound-absorbing layer under hydrostatic pressure by assessing structural deformation and changes in material parameters. This method solves the problem in related technologies where the simulation method for sound-absorbing layer performance cannot accurately simulate the effects of deformation and changes in material physical properties under high hydrostatic pressure, leading to the inaccurate prediction of the sound absorption performance of the sound-absorbing layer under high hydrostatic pressure.

[0025] See Figure 1 and Figure 2 As shown in the figure, this application provides a method for simulating the performance of a sound-absorbing layer under hydrostatic pressure, considering structural deformation and changes in material parameters. The method includes the following steps: S101. Establish a geometric model. In the simulation model, establish a geometric model of the sound-absorbing layer and a geometric model of the sound propagation medium. The sound-absorbing layer includes a rigid backing layer and a rubber layer. The rubber layer is attached to the rigid backing layer and has several periodic cavities inside.

[0026] S102. Define the physical field and boundary conditions. Define the solid mechanical physical field and the pressure acoustic physical field. Set the boundary conditions. The sound-absorbing layer is defined as the solid mechanical physical field. The periodic cavity region of the sound propagation medium and the sound-absorbing layer is defined as the pressure acoustic physical field. The boundary where the sound-absorbing layer and the sound propagation medium coincide is the sound-solid coupling boundary.

[0027] S103. Set the deformation region and transfer the structural deformation calculation results of the solid mechanical domain under hydrostatic pressure to the acoustic domain through the dynamic mesh interface. The function of the dynamic mesh interface is to input the deformation calculation results of the solid mechanical domain into the acoustic domain in real time and dynamically, so that the acoustic calculation is based on the geometric model of the sound-absorbing layer after real deformation, thereby solving the core problem of "inaccurate simulation of sound absorption performance under high hydrostatic pressure".

[0028] S104. Coupling of material parameter changes with hydrostatic pressure: This involves coupling the mechanical parameters of the sound-absorbing layer material with the magnitude of the hydrostatic pressure, enabling the mechanical parameters of the sound-absorbing layer material to change dynamically with variations in hydrostatic pressure. The mechanical parameters are obtained based on actual experimental testing. These mechanical parameters include at least one of Young's modulus, Poisson's ratio, shear modulus, bulk modulus, or a combination of transverse wave velocity and longitudinal wave velocity.

[0029] S105. Sequential calculation of mechanical and acoustic solutions: The mechanical deformation solution and acoustic solution are performed in series in two steps. The first step is the mechanical deformation solution, which calculates the deformation of the sound-absorbing layer caused by hydrostatic pressure. The second step is the acoustic solution, in which the frequency points to be calculated are set, and the acoustic performance of the sound-absorbing layer after deformation caused by hydrostatic pressure is calculated to obtain the sound absorption performance results of the sound-absorbing layer.

[0030] Traditional methods separate deformation calculation and acoustic calculation into two independent calculation models. The deformation results under hydrostatic pressure are introduced into the acoustic calculation through geometric import. This method ignores the normal deformation of the sound-absorbing layer side when calculating deformation and cannot simultaneously couple material parameter changes into mechanical and acoustic calculations.

[0031] In this method, hydrostatic deformation calculation and acoustic calculation are directly coupled in series. The mechanical parameter changes can be coupled simultaneously in one model, which can greatly improve the calculation efficiency. In addition, the normal deformation of the side of the sound-absorbing layer is considered, and the calculation results are more consistent with the actual situation.

[0032] S106. After completing one series connection for mechanical deformation and acoustic solution, return to step S104 to recouple different mechanical parameters and different hydrostatic pressures of the sound-absorbing layer material, and continue to S105 for series connection for mechanical deformation and acoustic solution.

[0033] This step is based on the mechanical parameter data such as modulus and Poisson's ratio of the sound-absorbing layer material obtained from experimental tests under different hydrostatic pressures. In the simulation, the physical property parameters such as modulus and Poisson's ratio of the sound-absorbing layer material are coupled with the magnitude of hydrostatic pressure to realize the effect of simulating the change of material physical property parameters with the magnitude of hydrostatic pressure. This makes the simulation settings closer to the actual situation and improves the credibility of the simulation results.

[0034] The sound-absorbing layer performance simulation method of this application is based on the mechanical parameters of the sound-absorbing layer material under different hydrostatic pressures obtained by experimental testing, such as modulus and Poisson's ratio. During the simulation, the physical and mechanical parameters of the sound-absorbing layer material, such as modulus and Poisson's ratio, are coupled with the magnitude of hydrostatic pressure to simulate the change of the material's physical properties and mechanical parameters with the magnitude of hydrostatic pressure. This makes the simulation settings closer to the actual situation and improves the credibility of the simulation results.

[0035] By setting up deformation regions and serial calculation steps for mechanical and acoustic solutions, deformation calculations and acoustic calculations under hydrostatic pressure are coupled in one model. The normal deformation of the sound-absorbing layer side and the changes in material mechanical parameters under hydrostatic pressure are also considered, thereby improving the reliability and computational efficiency of the sound absorption performance simulation under varying hydrostatic pressure.

[0036] In some alternative embodiments, see Figure 1 and Figure 2 As shown, this application provides a method for simulating the performance of a sound-absorbing layer under hydrostatic pressure, considering structural deformation and material parameter changes. The method establishes a geometric model of the sound-absorbing layer and a geometric model of the sound propagation medium in step S101, specifically including: S101a. Establish a geometric model of the sound-absorbing layer based on the actual design. To achieve low-frequency broadband sound absorption, the sound-absorbing layer usually has a periodic structure. To simplify the computation of the simulation model, a geometric model of the sound-absorbing layer containing one or several cycles can be established, and reasonable boundary conditions can be set to simulate a large sound-absorbing layer. Alternatively, a full-size sound-absorbing layer model can be established if the computing power allows.

[0037] S101b. Establish a geometric model of the sound propagation medium, which can be water, air, or both water and air in segments. The sound wave incident end of the sound-absorbing layer coincides with one end of the water segment, and the back of the rigid backing layer of the sound-absorbing layer coincides with one end of the water or air segment. A perfectly matched layer is set to simulate an infinite domain to eliminate the effects of sound reflection, refraction, and reverberation. By setting reasonable boundary conditions, the infinite expansion of the propagation medium domain on both sides can be simulated.

[0038] In some alternative embodiments, see Figure 1 and Figure 2 As shown, this application provides a method for simulating the performance of a sound-absorbing layer under hydrostatic pressure by structural deformation and material parameter changes. In S102, the sound-absorbing layer is defined as a solid mechanical physical field to obtain the deformation results under hydrostatic pressure. A deformation region is set for mechanical calculation. In the mechanical calculation, the lower boundary of the sound-absorbing layer is defined as a fixed boundary, and a pressure load is applied to the upper boundary of the sound-absorbing layer to simulate hydrostatic pressure.

[0039] The periodic cavity region of the sound propagation medium and the sound-absorbing layer is defined as a pressure acoustic physics field. Acoustic calculations are performed on this region, and incident sound field conditions are added to the medium domain, with the sound wave propagation direction pointing towards the sound-absorbing layer to simulate the incident sound wave. The upper and lower ends of the sound-absorbing layer coincide with the sound propagation medium, forming acoustic-structure coupling boundaries. The boundary conditions on both sides of the sound-absorbing layer geometric model and the sound propagation medium geometric model are defined as periodic boundaries to simulate a large sound-absorbing layer.

[0040] In some alternative embodiments, see Figure 1 and Figure 2As shown, this application provides a method for simulating the performance of a sound-absorbing layer under hydrostatic pressure by analyzing structural deformation and material parameter changes. The method sets a deformation region in S103 and transfers the structural deformation calculation results from the solid mechanics domain to the acoustic domain through a dynamic mesh interface. Specifically, it includes: S103a. Set a deformation domain in the geometric model of the sound-absorbing layer. Select the acoustic calculation domain as the deformation domain. After the mechanical deformation results are solved, the geometric model will be reconstructed based on the deformation calculation results of the sound-absorbing layer structure, and then acoustic calculations will be performed.

[0041] S103b: The structural deformation calculation results of the solid mechanical domain under hydrostatic pressure are transferred to the acoustic domain through the dynamic mesh interface. The acoustic domain directly uses the deformed geometric model to calculate the sound absorption performance, so that the structural deformation of the sound-absorbing layer is related to the acoustic performance of the sound-absorbing layer.

[0042] In some alternative embodiments, see Figure 1 and Figure 2 As shown, this application provides a method for simulating the performance of a sound-absorbing layer under hydrostatic pressure, considering structural deformation and material parameter changes. The method further includes the following steps before step S105: The geometric model of the sound-absorbing layer is meshed. For areas where severe deformation is expected under hydrostatic pressure (such as the contact surface between the sound-absorbing layer and the water medium, and stress concentration), the mesh is densified (i.e., the number of elements is increased to make the mesh finer) to avoid mesh distortion affecting the computational convergence after large deformation. Mesh quality indicators are also controlled to avoid high aspect ratio, small interior angle, or twisted elements (e.g., limiting aspect ratio <10, interior angle >30°, and twist <0.9).

[0043] In some alternative embodiments, see Figure 1 and Figure 2 As shown, this application provides a method for simulating the performance of a sound-absorbing layer under hydrostatic pressure, considering structural deformation and material parameter changes. The method involves sequentially solving for mechanical deformation and acoustic properties in step S105, specifically including: First, the structural deformation of the sound-absorbing layer under hydrostatic pressure is calculated using solid mechanical physics. The deformation results are then automatically transferred to the pressure acoustic physics as real-time input for acoustic calculations. In the same simulation model, the sound absorption is calculated directly based on the deformed geometry.

[0044] The sound absorption performance of the sound-absorbing layer is obtained through the formula. The calculation yielded, where The sound absorption coefficient is... To reflect sound pressure, The incident sound pressure is taken as the average value of a cross-section (a line in a two-dimensional model) parallel to the interface between the water medium and the sound-absorbing layer, or near the contact surface. The performance of the sound-absorbing layer can be optimized by iterative calculation of the model.

[0045] Current low-frequency broadband sound-absorbing layers are usually designed with special structures such as periodic cavities. Under high hydrostatic pressure, changes in the mechanical parameters of the material and deformation of the geometric structure of the sound-absorbing layer can lead to the failure of the sound absorption mechanism and significant changes in the performance of the sound-absorbing layer. Existing simulation methods for the performance of sound-absorbing layers cannot accurately simulate the effects of deformation and changes in the physical properties of the material under high hydrostatic pressure.

[0046] This application proposes a method for simulating the sound absorption performance of sound-absorbing layers under different hydrostatic pressures by simultaneously considering structural deformation under hydrostatic pressure and incorporating test results of material mechanical parameters under varying hydrostatic pressures. This improves the consistency between the simulated performance calculations and actual conditions. This simulation method can provide guidance for the design of high hydrostatic pressure resistant sound-absorbing layers and is applicable to the simulation of sound-absorbing layer performance under waveguide conditions and free-field conditions.

[0047] The technical solution of this sound-absorbing layer performance simulation method has the following key points: (1) The physical properties of the sound-absorbing layer change significantly with hydrostatic pressure. The Young's modulus and Poisson's ratio of the rubber material of the sound-absorbing layer are set as variables E and σ, respectively (shear modulus and bulk modulus, or a combination of transverse wave velocity and longitudinal wave velocity can also be used). In subsequent calculations, the material parameter variables are coupled with the hydrostatic pressure change to simulate the material parameter change under hydrostatic pressure. The specific values ​​of the rubber material parameters and hydrostatic pressure P are obtained from actual experimental tests. The accuracy and reliability of the acoustic calculation of the model are ensured by measuring the material parameters.

[0048] (2) Set up a deformation domain and transfer the structural deformation calculation results of the solid mechanical domain under hydrostatic pressure to the acoustic domain through the dynamic mesh interface, so as to associate the structural deformation of the sound-absorbing layer with its acoustic performance.

[0049] (3) Refine the mesh in areas where severe deformation is expected to occur to avoid mesh distortion after deformation due to sparse mesh. Also, pay attention to controlling mesh quality indicators to avoid high aspect ratio, small interior angle or twisted elements.

[0050] (4) The mechanical deformation and acoustic solutions are performed in series. The traditional method separates the deformation calculation and acoustic calculation into two independent calculation models and imports the deformation results under hydrostatic pressure into the acoustic calculation through geometric import. Compared with the traditional method, this method directly couples the hydrostatic deformation calculation and acoustic calculation. The parameter change coupling can be realized simultaneously in one model, which can greatly improve the calculation efficiency. In addition, it considers the normal deformation of the side of the sound-absorbing layer, and the calculation results are more consistent with the actual situation.

[0051] Working principle This application provides a simulation method for the performance of a sound-absorbing layer under hydrostatic pressure, considering structural deformation and material parameter changes. The method first establishes a geometric model of the sound-absorbing layer and a geometric model of the sound propagation medium. Then, it defines a solid mechanical field and a pressure acoustic field, setting boundary conditions. The sound-absorbing layer is defined as the solid mechanical field, while the sound propagation medium and the internal cavity of the sound-absorbing layer are defined as the pressure acoustic field. The boundary where the sound-absorbing layer and the sound propagation medium coincide is defined as the acoustic-solid coupling boundary. Next, a deformation region is set, and the structural deformation calculation results from the solid mechanical domain under hydrostatic pressure are transferred to the acoustic domain through a dynamic mesh interface. Then, the mechanical parameters of the sound-absorbing layer material are coupled with the magnitude of the hydrostatic pressure, with the mechanical parameters obtained from actual experimental tests. Finally, the mechanical deformation solution and the acoustic solution are performed in series to obtain the sound absorption performance results of the sound-absorbing layer.

[0052] Therefore, the sound-absorbing layer performance simulation method of this application is based on the mechanical parameters of the sound-absorbing layer material under different hydrostatic pressures obtained from experimental tests, such as modulus and Poisson's ratio. During simulation, the physical and mechanical parameters of the sound-absorbing layer material, such as modulus and Poisson's ratio, are coupled with the magnitude of hydrostatic pressure to simulate the changes in the material's physical properties and mechanical parameters with the magnitude of hydrostatic pressure. This makes the simulation settings closer to actual conditions and improves the reliability of the simulation results. By setting deformation regions and serial calculation steps, the deformation calculation under hydrostatic pressure is coupled with the acoustic calculation in a single model. Furthermore, considering the normal deformation of the sound-absorbing layer's side surface and the changes in the material's mechanical parameters under hydrostatic pressure, the reliability and computational efficiency of the sound absorption performance simulation under varying hydrostatic pressure are improved.

[0053] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0054] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0055] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for simulating the performance of a sound-absorbing layer under hydrostatic pressure, characterized in that, The method includes: Establish the geometric model of the sound-absorbing layer and the geometric model of the sound propagation medium; Define the solid mechanical physical field and the pressure acoustic physical field, and set the boundary conditions, wherein the sound-absorbing layer is the solid mechanical physical field, the sound propagation medium and the internal cavity of the sound-absorbing layer are the pressure acoustic physical field, and the boundary of the sound-absorbing layer and the sound propagation medium is the sound-solid coupling boundary. A deformation region is set up, and the structural deformation calculation results of the solid mechanics domain under hydrostatic pressure are transferred to the acoustic domain through the dynamic mesh interface; The mechanical parameters of the sound-absorbing layer material are coupled with the magnitude of the hydrostatic pressure, and the mechanical parameters are obtained based on actual experimental tests. The mechanical deformation and acoustic solutions are performed in series to obtain the sound absorption performance results of the sound-absorbing layer.

2. The method for simulating the performance of a sound-absorbing layer under hydrostatic pressure based on structural deformation and material parameter changes as described in claim 1, characterized in that, Establishing the geometric models of the sound-absorbing layer and the sound propagation medium, specifically including: The sound-absorbing layer has a periodic sound-absorbing structure inside. One or more periodic sound-absorbing layer geometric models are established based on the calculation amount of the simulation model. A large sound-absorbing layer model or a full-size sound-absorbing layer model is simulated by setting boundary conditions. The sound propagation medium includes water, air, or a combination of both. The sound wave incident end of the sound-absorbing layer coincides with one end of the water medium segment, and the rigid backing end of the sound-absorbing layer coincides with one end of the water or air medium. A perfectly matched layer is provided to simulate an infinite domain.

3. The method for simulating the performance of a sound-absorbing layer under hydrostatic pressure based on structural deformation and material parameter changes as described in claim 1, characterized in that: The sound-absorbing layer is defined as a solid mechanical physical field to obtain the deformation results under hydrostatic pressure. Deformation areas are set for mechanical calculations. In the mechanical calculations, the lower boundary of the sound-absorbing layer is defined as a fixed boundary, and a pressure load is applied to the upper boundary of the sound-absorbing layer to simulate hydrostatic pressure. The sound propagation medium and the sound-absorbing layer are defined as pressure acoustic physical fields. An incident sound field condition is added to the medium domain, and the sound wave propagation direction is pointed towards the sound-absorbing layer to simulate the incident sound wave. The boundary conditions on both sides of the geometric model of the sound-absorbing layer and the geometric model of the sound propagation medium are defined as periodic boundaries.

4. The method for simulating the performance of a sound-absorbing layer under hydrostatic pressure based on structural deformation and material parameter changes as described in claim 1, characterized in that, The deformation region is defined, and the structural deformation calculation results of the solid mechanics domain under hydrostatic pressure are transferred to the acoustic domain through the dynamic mesh interface. Specifically, this includes: A deformation domain is set in the geometric model of the sound-absorbing layer. The deformation domain is selected as the acoustic calculation domain. After the mechanical deformation results are solved, the geometric model is reconstructed based on the deformation calculation results of the sound-absorbing layer structure, and then the acoustic calculation is performed. The structural deformation calculation results of the solid mechanical domain under hydrostatic pressure are transferred to the acoustic domain through the dynamic mesh interface. The acoustic domain directly uses the deformed geometric model to calculate the sound absorption performance, so that the structural deformation of the sound-absorbing layer is related to the acoustic performance of the sound-absorbing layer.

5. The method for simulating the performance of a sound-absorbing layer under hydrostatic pressure based on structural deformation and material parameter changes as described in claim 1, characterized in that: The mechanical parameters include at least one of Young's modulus, Poisson's ratio, shear modulus, and bulk modulus.

6. The method for simulating the performance of a sound-absorbing layer under hydrostatic pressure based on structural deformation and material parameter changes as described in claim 1, characterized in that, The method further includes: The geometric model of the sound-absorbing layer is meshed, and the mesh is refined in areas where the expected deformation is severe under hydrostatic pressure to avoid mesh distortion after large deformation affecting the calculation convergence. In addition, the mesh quality index is controlled to avoid high aspect ratio, small interior angle or twisted elements.

7. The method for simulating the performance of a sound-absorbing layer under hydrostatic pressure based on structural deformation and material parameter changes as described in claim 1, characterized in that, The mechanical deformation and acoustic solutions are performed in series, specifically including: First, the structural deformation of the sound-absorbing layer under hydrostatic pressure is calculated using solid mechanical physics. The deformation results are then automatically transferred to the pressure acoustic physics as real-time input for acoustic calculations. In the same simulation model, the sound absorption is calculated directly based on the deformed geometry.

8. The method for simulating the performance of a sound-absorbing layer under hydrostatic pressure based on structural deformation and material parameter changes as described in claim 1, characterized in that: The sound absorption performance of the sound-absorbing layer is obtained through the formula. The calculation yielded, where The sound absorption coefficient is... To reflect sound pressure, This is the incident sound pressure.

9. The method for simulating the performance of a sound-absorbing layer under hydrostatic pressure based on structural deformation and material parameter changes as described in claim 1, characterized in that: After completing one series connection for mechanical deformation and acoustic solutions, the mechanical deformation and acoustic solutions are then performed again by coupling different mechanical parameters and hydrostatic pressure of the sound-absorbing layer material.

10. The method for simulating the performance of a sound-absorbing layer under hydrostatic pressure based on structural deformation and material parameter changes as described in claim 1, characterized in that: The sound-absorbing layer includes a rigid backing layer and a rubber layer. The rubber layer is attached to the rigid backing layer and has several periodic cavities inside.

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