A method and apparatus for three-dimensional acoustic elasticity calculation in a horizontally non-uniform channel environment

Abstract

This application discloses a three-dimensional acoustic elasticity calculation method and apparatus in a horizontally non-uniform channel environment, relating to the field of electronic digital data processing. The method establishes a finite element model and a wetted surface element mesh model of an underwater three-dimensional structure, and performs fluid-structure interaction acoustic elasticity calculations to obtain the point sound source intensity of each wetted surface element on the structure's wetted surface. Then, using the Gaussian ray tracing method, it calculates the underwater acoustic Green's function value of each wetted surface element at the observation point based on various acoustic field environmental parameters of the horizontally non-uniform channel environment in which the underwater three-dimensional structure is located. Finally, it combines the point sound source intensity of each wetted surface element with the superposition of these values ​​to obtain the sound pressure level of the underwater three-dimensional structure at the observation point. Based on the characteristics of three-dimensional acoustic elasticity theory and the Gaussian ray tracing method, this method can achieve efficient calculation of the frequency domain sound pressure level at any observation point in a horizontally non-uniform channel environment, meeting the needs of efficient simulation calculation of the radiated sound field of underwater three-dimensional structures in a real marine environment.

Description

Technical Field

[0001] This application relates to the field of electronic digital data processing, and in particular to a method and apparatus for calculating three-dimensional acoustic elasticity in a horizontally non-uniform channel environment. Background Technology

[0002] The acoustic radiation characteristics of underwater three-dimensional structures are not only related to the coupled vibrations of the structure itself and the water medium, but also closely related to the surrounding marine acoustic environment. To accurately describe this physical phenomenon, existing research has combined three-dimensional hydroelasticity theory with underwater acoustic channel theory, proposing a three-dimensional acoustoelastic theory. Within this theoretical framework, the elastic vibration response of underwater three-dimensional structures in fluids and the sound field propagation problem are solved jointly. The computational accuracy and efficiency of the Green's function directly determine the ability of the acoustoelastic model in predicting radiated sound fields.

[0003] In existing three-dimensional acoustoelastic analysis methods, some techniques have introduced normal mode methods to solve the Green's function, thereby enabling far-field sound propagation calculations in horizontally homogeneous environments. For example, patent application CN201810684703.9, entitled "A Shallow-Sea Sound Propagation Calculation Method Applied to Three-Dimensional Acoustastic Analysis of Ships," exemplifies this approach. Normal mode methods effectively handle the refraction effects caused by depth variations in sound velocity profiles and utilize modal superposition to achieve rapid sound field solutions. Therefore, underwater acoustic propagation calculations based on normal mode methods offer advantages such as high computational speed and high accuracy in far-field sound pressure calculations. However, they also have limitations, including unsuitability for horizontally non-uniform channel environments and low near-field accuracy. Real-world marine environments often exhibit significant horizontal non-uniformity, resulting in low adaptability and robustness of three-dimensional acoustoelastic calculations based on normal mode methods in real-world marine environments. Summary of the Invention

[0004] This application addresses the aforementioned problems and technical requirements by proposing a three-dimensional acoustoelasticity calculation method and apparatus in a horizontally non-uniform channel environment. The technical solution of this application is as follows: A method for calculating three-dimensional acoustic elasticity in a horizontally non-uniform channel environment, comprising: A finite element model of an underwater three-dimensional structure and a wet surface element mesh model of the corresponding wet surface of the structure are established. Based on the finite element model and the wet surface element mesh model, fluid-structure coupled acoustoelastic calculations are performed to obtain the source intensity of each wet surface element on the wet surface of the structure in the finite element model. Using the Gaussian ray method, based on various acoustic field environment parameters of the fluid domain in which the underwater three-dimensional structure is located, the underwater acoustic Green function values ​​at the observation points of each wet surface element on the wet surface of the finite element model in a horizontally non-uniform channel environment are calculated; wherein, at least one acoustic field environment parameter in the fluid domain changes along the horizontal direction, forming a horizontally non-uniform channel environment. The sound pressure level of the underwater three-dimensional structure at the observation point is obtained by combining the sound source intensity of each wet surface element on the wet surface element with the water acoustic Green function value at the observation point in a horizontal non-uniform channel environment.

[0005] A further technical solution involves calculating the underwater acoustic Green's function values ​​at observation points on the wetted surface of the finite element model in a horizontally non-uniform channel environment, including: The Bellhop program is configured with parameters based on various acoustic field environment parameters of the fluid domain, coordinates of the point sound source intensity of each wet surface element on the wet surface of the three-dimensional structure, and coordinates of the observation point. The Bellhop program is then called to calculate the underwater acoustic Green function value of each wet surface element on the wet surface of the finite element model at the observation point in a horizontally non-uniform channel environment.

[0006] A further technical solution involves calculating the underwater acoustic Green's function values ​​at observation points on the wetted surface of the finite element model in a horizontally non-uniform channel environment, including: Based on the principle of acoustic field reciprocity, the sound source information in the Bellhop program is configured according to the coordinates of the observation points, and the field point information in the Bellhop program is configured according to the coordinates of each wet surface element on the wet surface of the finite element model. The Bellhop program is then called to obtain the underwater acoustic Green function values ​​at the observation points of all wet surface elements on the wet surface of the finite element model in a horizontally non-uniform channel environment.

[0007] Further technical solutions include: the three-dimensional acoustic elasticity calculation method in a horizontally non-uniform channel environment also includes: The program iterates through each frequency point within the target frequency range and calls the Bellhop program once at each frequency point to obtain the underwater acoustic Green function values ​​of all wetted surface elements at the current frequency point in the horizontal non-uniform channel environment. The sound pressure level of the underwater three-dimensional structure at the current frequency point in the horizontal non-uniform channel environment is obtained by superimposing the source intensity of each wetted surface element at the current frequency point.

[0008] A further technical solution is that at least one acoustic field environmental parameter varies in the horizontal direction in the sound velocity profile of the fluid domain where the underwater three-dimensional structure is located and in the seabed topography.

[0009] A further technical solution involves superimposing the sound pressure levels of the underwater three-dimensional structure at the observation point, including: Based on the underwater acoustic Green's function values ​​of each wet surface element on the structured wet surface in a horizontally non-uniform channel environment, and combined with the superposition of the point sound source intensity of each wet surface element, the observation points in the horizontally non-uniform channel environment are obtained. The sound field velocity potential at that location :

[0010] in, It is a wetted surface element on the structure of the finite element model. The sound source is strong. It is a wet noodle. Observation points in a horizontally non-uniform channel environment The Green function value of the underwater acoustic field at that location. It is the wet surface of the structure in the finite element model. Indicated on the wet surface of the structure Integrate the area on top; Based on observation points in a horizontally non-uniform channel environment The sound field velocity potential at that location The sound pressure level of the underwater three-dimensional structure at the observation point in a horizontally non-uniform channel environment is obtained.

[0011] A three-dimensional acoustic elasticity calculation device for a horizontally non-uniform channel environment, the device comprising: The model building module is used to build finite element models of underwater three-dimensional structures and corresponding wet surface element mesh models of the wet surface of the structure. The point source intensity calculation module is used to perform fluid-structure interaction acoustoelastic calculations based on the finite element model and the wetted surface element mesh model to obtain the point source intensity of each wetted surface element on the wetted surface of the structure in the finite element model. The Green's function calculation module is used to calculate the underwater acoustic Green's function values ​​at observation points on the wetted surface elements of the finite element model in a horizontally non-uniform channel environment based on various acoustic field environment parameters of the fluid domain in which the underwater three-dimensional structure is located, using the Gaussian ray method. In this case, at least one acoustic field environment parameter in the fluid domain changes along the horizontal direction, forming a horizontally non-uniform channel environment. The acoustic propagation calculation module is used to obtain the sound pressure level of the underwater three-dimensional structure at the observation point based on the underwater acoustic Green function value of each wet surface element on the wet surface of the structure at the observation point in a horizontal non-uniform channel environment, combined with the superposition of the point sound source intensity of each wet surface element.

[0012] A further technical solution is that the Green function calculation module is also used to configure the Bellhop program according to the various acoustic field environment parameters of the fluid domain, the coordinates of the point sound source intensity of each wet surface element on the wet surface of the three-dimensional structure, and the coordinates of the observation point, and call the Bellhop program to calculate the underwater acoustic Green function value of each wet surface element on the wet surface of the finite element model at the observation point in the horizontal non-uniform channel environment.

[0013] A further technical solution is that the Green function calculation module is also used to configure the sound source information in the Bellhop program according to the coordinates of the observation point based on the principle of sound field reciprocity, and to configure the field point information in the Bellhop program according to the coordinates of each wet surface element on the structure wet surface of the finite element model; and to call the Bellhop program to obtain the underwater acoustic Green function values ​​of all wet surface elements on the structure wet surface of the finite element model at the observation points in the horizontal non-uniform channel environment.

[0014] The further technical solution is that the Green function calculation module is also used to traverse each frequency point in the target frequency range in turn, and call the Bellhop program once at each frequency point to obtain the underwater acoustic Green function value of all wet surface elements at the current frequency point in the observation point of the horizontal non-uniform channel environment. The sound propagation calculation module is also used to obtain the sound pressure level of the underwater three-dimensional structure at the observation point in a horizontally non-uniform channel environment at the current frequency point by combining the underwater acoustic Green function values ​​of all wetted surface elements at the observation point with the point sound source intensity of each wetted surface element at the current frequency point.

[0015] The beneficial technical effects of this application are: This application discloses a three-dimensional acoustic elasticity calculation method in a horizontally non-uniform channel environment. This method introduces the Gaussian ray method into the three-dimensional acoustic elasticity analysis technology to calculate the underwater acoustic Green's function value. Taking advantage of the Gaussian ray method's ability to be applied in relatively complex medium and boundary conditions, this method can achieve efficient calculation of the frequency domain sound pressure level at any observation point in a horizontally non-uniform channel environment. This realizes the application of the three-dimensional acoustic elasticity calculation method in a more universal horizontally non-uniform channel environment, thereby meeting the needs of efficient simulation calculation of the radiated sound field of underwater three-dimensional structures in a real marine environment.

[0016] This method calls the Bellhop program to calculate the underwater acoustic Green's function value of a single observation point in a horizontally non-uniform channel environment. Addressing the constraint that the Bellhop program can only configure one sound source but multiple field points at a time, this method creatively uses the principle of sound field reciprocity to treat the observation point as the sound source in the Bellhop program and the wetted surface element as the field point. This reduces the number of Bellhop program calls at a single frequency point from the number of wetted surface elements to one, significantly improving computational efficiency. While achieving the same level of computational accuracy as existing commercial software, this method far surpasses the computational efficiency of existing commercial software. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating a three-dimensional acoustoelasticity calculation method in one embodiment of this application.

[0018] Figure 2 This is a schematic diagram of COMSOL finite element modeling in a simulation example.

[0019] Figure 3 yes Figure 2 In the simulation examples, a comparison of the sound pressure level frequency curves at the observation points obtained using the three-dimensional acoustic elasticity calculation method of this application and COMSOL software are shown.

[0020] Figure 4 This is a structural block diagram of a three-dimensional acoustic elasticity calculation device in one embodiment of this application. Detailed Implementation

[0021] The specific embodiments of this application will be further described below with reference to the accompanying drawings.

[0022] This application discloses a three-dimensional acoustoelasticity calculation method under a horizontally non-uniform channel environment. The method includes the following steps, please refer to [reference needed]. Figure 1 The flowchart shown is as follows: Step 1: Establish the finite element model of the underwater three-dimensional structure, i.e., the dry model, and the wet surface element mesh model of the corresponding wet surface of the structure. The specific establishment method can refer to existing methods, which will not be elaborated here.

[0023] Step 2: Based on the finite element model and wet surface element mesh model of the underwater three-dimensional structure, perform fluid-structure interaction acoustoelastic calculations to obtain the point sound source intensity of each wet surface element on the wet surface of the structure in the finite element model.

[0024] This step can refer to existing mature methods, including: performing modal analysis on the finite element model to obtain modal parameters. The modal parameters include at least the modal frequencies and mode shapes. Specifically, the Lanczos method can be used. After setting the boundary conditions and the required output frequency range, the modal analysis can be performed automatically.

[0025] Then, fluid-structure interaction (FSI) boundary conditions are determined for each mode. Based on the modal parameters and the FSI boundary conditions, the point source intensity and generalized hydrodynamic coefficients of each mode of the underwater 3D structure are obtained. The principal coordinate response of each mode is then calculated based on the applied load and the generalized hydrodynamic coefficients. After determining the FSI boundary conditions, point source intensity, generalized hydrodynamic coefficients, and principal coordinate response for each mode, the point source intensity of each mode is multiplied by the corresponding principal coordinate response and superimposed to obtain the point source intensity of each wetted surface element on the wetted surface of the structure. In other words, the point source intensity of each wetted surface element on the wetted surface of the structure obtained in this step is the actual total point source intensity after superimposing the point source intensity of each mode.

[0026] Step 3: Using the Gaussian ray tracing method, calculate the underwater acoustic Green function values ​​at the observation points of each wet surface element on the wet surface of the finite element model in a horizontally non-uniform channel environment based on the various acoustic field environment parameters of the fluid domain where the underwater three-dimensional structure is located.

[0027] In this application, the fluid domain containing the underwater three-dimensional structure exhibits at least one acoustic field environmental parameter that varies horizontally, forming a horizontally non-uniform channel environment. These acoustic field environmental parameters include sound velocity profile, seabed topography, density, and attenuation coefficient. The sound velocity profile at each horizontal location represents the relationship between the sound velocity and seawater depth at that location. Considering the characteristics of a real marine environment, in one embodiment, at least one acoustic field environmental parameter in the sound velocity profile and seabed topography of the fluid domain containing the underwater three-dimensional structure varies horizontally.

[0028] The Gaussian ray method is a classic calculation method in underwater acoustic propagation theory. It is characterized by its simple and intuitive physical meaning and its ability to be applied well in complex media and boundary conditions, making it suitable for calculations in horizontally non-uniform channel environments. This application integrates it with three-dimensional acoustoelasticity calculations. After calculating the underwater acoustic Green's function values ​​at observation points in a horizontally non-uniform channel environment where the sound velocity profile and / or seabed topography vary along horizontal distance using the Gaussian ray method, a series of monopole point sound sources of different intensities are superimposed based on three-dimensional acoustoelasticity theory to obtain the sound pressure level at the observation points in the horizontally non-uniform channel environment.

[0029] The Bellhop program is currently the most classic open-source code for the Gaussian ray method. Therefore, in one embodiment, the Bellhop program is configured with parameters according to the determined acoustic field environment parameters of the fluid domain, the coordinates of the point sound source intensity of each wet surface element on the wet surface of the three-dimensional structure, and the coordinates of the observation point. Then, by calling the Bellhop program, the underwater acoustic Green function value of each wet surface element on the wet surface of the finite element model at the observation point in a horizontal non-uniform channel environment can be calculated.

[0030] Following the traditional parameter configuration method of the Bellhop program, to calculate the underwater acoustic Green's function value of each wetted surface element at the observation point in a horizontally non-uniform channel environment, it is necessary to configure the sound source information in the Bellhop program according to the coordinates of the wetted surface element and the field point information according to the coordinates of the observation point. However, due to the inherent constraint that the Bellhop program can only define one sound source per calculation, this approach can only obtain the underwater acoustic Green's function value of a single wetted surface element at the observation point in a horizontally non-uniform channel environment with each call to the Bellhop program. To obtain the underwater acoustic Green's function value of each wetted surface element on the structural wetted surface of the finite element model at the observation point in a horizontally non-uniform channel environment, it is necessary to configure the sound source information in the Bellhop program according to the coordinates of each wetted surface element and perform multiple calculations. However, the number of wetted surface elements on the structural wetted surface of the finite element model is large, and the number of wetted surface elements in large-scale finite element models is often close to tens of thousands. To obtain the underwater acoustic Green's function value of all wetted surface elements at the observation point in a horizontally non-uniform channel environment, it is necessary to configure and call the Bellhop program tens of thousands of times, which is very time-consuming and inefficient.

[0031] To avoid the aforementioned problem of long computation time, one embodiment optimizes the parameter configuration and calling method of the Bellhop program. Although the Bellhop program can only define one sound source per calculation, it can define multiple field points, and the computation time for multiple field points is within an acceptable range. Therefore, in this embodiment, based on the principle of sound field reciprocity, the sound source information in the Bellhop program is configured according to the coordinates of the observation points, and the field point information in the Bellhop program is configured according to the coordinates of each wet surface element on the wet surface of the finite element model. The specific configuration method is based on the parameter configuration rules of the Bellhop program, including: Configure the number of sound sources in the Bellhop program to 1, the depth of the sound source to be the same as the depth of the observation point, and the horizontal distance of the sound source to 0.

[0032] The number of field points in the Bellhop program is configured to be the total number of wetted elements on the wetted surface of the finite element model. The field point coordinates for each wetted element include the depth of the current wetted element and the horizontal distance between the current wetted element and the observation point. Since wetted elements are often irregularly distributed compared to observation points, when configuring the field point information in the Bellhop program, the last digit of the run type is usually defined as "I", that is, the field point coordinate method is defined as irregular mesh, and the field point coordinates corresponding to each wetted element are defined separately.

[0033] With this configuration, the hydroacoustic Green function values ​​of all wet surface elements on the wet surface of the finite element model at the observation point can be obtained in one go by calling the Bellhop program.

[0034] Step 4: Based on the underwater acoustic Green function values ​​of each wet surface element on the structure at the observation point in a horizontally non-uniform channel environment, and combined with the superposition of the point sound source intensity of each wet surface element, the sound pressure level of the underwater three-dimensional structure at the observation point is obtained.

[0035] After obtaining the underwater acoustic Green's function values ​​at the observation points of each wetted surface element in the horizontally non-uniform channel environment through step 3, the observation points are obtained by combining the underwater acoustic Green's function values ​​of each wetted surface element on the structural wetted surface of the finite element model with the point source intensity superposition of each wetted surface element. The sound field velocity potential at that location :

[0036] in, It is the wet surface of the structure in the finite element model. Indicated on the wet surface of the structure Integrate the area on top. It is a wetted surface element on the structure of the finite element model. The sound source is strong. It is the calculated wet surface element At the observation point The underwater acoustic Green's function value at a certain point, i.e., the propagation of a monopole point source in a marine acoustic waveguide, satisfies the following equation:

[0037] in, For the Laplace operator. This represents the Green's function value for underwater acoustics. The harmonic time factor is taken as... , Angular frequency, For time, The unit of coefficient is... For sound wave number, It is the speed of sound in a horizontally non-uniform channel environment formed by a fluid domain, and it varies with spatial location. It is a three-dimensional Dirac function.

[0038] Finally, based on the observation points The sound field velocity potential at that location This will allow us to obtain the sound pressure level of the underwater three-dimensional structure at the observation point; for details, please refer to existing methods.

[0039] In practical applications, it is often necessary to perform sound radiation calculations at multiple different frequency points. Therefore, the process involves sequentially traversing each frequency point within the target frequency range, and at each frequency point, calling the Bellhop program once (step 3) to obtain the underwater acoustic Green's function values ​​at the observation points of all wetted surface elements in a horizontally non-uniform channel environment at the current frequency point. Then, following step 4, the sound pressure level of the underwater 3D structure at the observation points in a horizontally non-uniform channel environment at the current frequency point is obtained by superimposing the point source intensities of each wetted surface element. After traversing all frequency points within the target frequency range, the sound pressure levels of the underwater 3D structure at different frequency points in a horizontally non-uniform channel environment can be obtained.

[0040] In a simulation example, an acoustoelastic analysis was performed on an underwater three-dimensional structure with a capsule shell subjected to a unit force at its bottom. The underwater three-dimensional structure has a spherical head / cylindrical radius of 0.5 m, a cylindrical section length of 2 m, a thickness of 0.01 m, an elastic modulus of 210 GPa, a Young's modulus of 0.3, and a density of 7800 kg / m³. 3 After establishing a finite element model of the underwater three-dimensional structure, the three-dimensional acoustic elasticity calculation method of this application and the commercial multiphysics coupled finite element software COMSOL were used to perform three-dimensional acoustic elasticity calculations on the finite element model under a horizontally non-uniform channel environment. The COMSOL model and the set horizontally non-uniform channel environment are as follows: Figure 2 As shown in the simulation example, the seabed topography of the fluid domain where the underwater three-dimensional structure is located slopes horizontally. Figure 2 The image shows two endpoints of a sloping seabed topography (200, -200) and (550, -170), and compares the sound pressure level spectra at the observation point (500, -30) in a horizontally non-uniform channel environment obtained by the two methods. Figure 3 As shown, by Figure 3 The results show that the sound pressure level spectrum curves obtained by the two methods at the observation points have good overlap, and even at the peak, the error is controlled within a relatively small and acceptable range. This proves that the accuracy and precision of the three-dimensional acoustic elasticity calculation method of this application can reach the same level as COMSOL software. Moreover, the calculation time of the three-dimensional acoustic elasticity calculation method of this application is half an hour, while the calculation time of COMSOL software is 12 hours. The solution efficiency of the three-dimensional acoustic elasticity calculation method of this application is much higher than that of COMSOL software.

[0041] This application also discloses a three-dimensional acoustoelasticity calculation device for horizontally non-uniform channel environments. Please refer to [reference needed]. Figure 4 The three-dimensional acoustic elasticity calculation device for this horizontally non-uniform channel environment includes a model building module, a point sound source intensity calculation module, a Green's function calculation module, and a sound propagation calculation module. The model building module is used to build finite element models of underwater three-dimensional structures and corresponding wet surface element mesh models of the wet surfaces of the structures.

[0042] The point sound source intensity calculation module is used to perform fluid-structure interaction acoustoelastic calculations based on the finite element model and the wetted surface element mesh model to obtain the point sound source intensity of each wetted surface element on the wetted surface of the structure in the finite element model.

[0043] The Green's function calculation module is used to calculate the underwater acoustic Green's function values ​​at observation points on the wetted surface elements of the finite element model in a horizontally non-uniform channel environment based on various acoustic field environment parameters of the fluid domain in which the underwater three-dimensional structure is located, using the Gaussian ray method. In this case, at least one acoustic field environment parameter in the fluid domain changes along the horizontal direction, forming a horizontally non-uniform channel environment.

[0044] The acoustic propagation calculation module is used to obtain the sound pressure level of the underwater three-dimensional structure at the observation point based on the underwater acoustic Green function value of each wet surface element on the wet surface of the structure at the observation point in a horizontal non-uniform channel environment, combined with the superposition of the point sound source intensity of each wet surface element.

[0045] In another embodiment, the Green function calculation module is also used to configure the Bellhop program according to the various acoustic field environment parameters of the fluid domain, the coordinates of the point sound source intensity of each wet surface element on the structural wet surface of the three-dimensional structure, and the coordinates of the observation point, and call the Bellhop program to calculate the underwater acoustic Green function value of each wet surface element on the structural wet surface of the finite element model at the observation point in the horizontal non-uniform channel environment.

[0046] In another embodiment, the Green function calculation module is also used to configure the sound source information in the Bellhop program according to the coordinates of the observation point based on the principle of acoustic field reciprocity, and to configure the field point information in the Bellhop program according to the coordinates of each wet surface element on the structural wet surface of the finite element model; and to call the Bellhop program to obtain the underwater acoustic Green function values ​​of all wet surface elements on the structural wet surface of the finite element model at the observation points in the horizontal non-uniform channel environment.

[0047] In another embodiment, the Green's function calculation module is further configured to sequentially traverse each frequency point within the target frequency range and call the Bellhop program once at each frequency point to obtain the underwater acoustic Green's function values ​​of all wetted surface elements at the current frequency point in a horizontally non-uniform channel environment. The sound propagation calculation module is further configured to combine the underwater acoustic Green's function values ​​of all wetted surface elements at each frequency point with the point sound source intensity superposition of each wetted surface element at the current frequency point to obtain the sound pressure level of the underwater three-dimensional structure at the current frequency point in a horizontally non-uniform channel environment.

[0048] It should be noted that the existing THAFTS-Acoustic 1.1 software for three-dimensional acoustic elasticity analysis of ships already has the function of calculating the underwater acoustic Green's function value using the normal mode method, thus enabling far-field sound propagation calculations in a horizontally uniform environment. The existing THAFTS-Acoustic software integrates functions such as model building, fluid-structure interaction acoustic elasticity calculation, and sound propagation calculation. Therefore, the three-dimensional acoustic elasticity calculation device for a horizontally non-uniform channel environment in this embodiment can be obtained directly by combining the Green's function calculation module with the existing THAFTS-Acoustic software. This includes directly calling existing functional modules in the THAFTS-Acoustic software to implement the functions of the model building module and the point source intensity calculation module. Users only need to complete steps such as modeling the wetted surface element, applying loads, and setting environmental parameters in the interactive interface to automatically calculate the point source intensity of the wetted surface element. Then, the Green's function calculation module of this embodiment is used to calculate the underwater acoustic Green's function value at the observation point of each wetted surface element in a horizontally non-uniform channel environment. The existing functional modules in the THAFTS-Acoustic software are called to calculate the sound pressure level of the underwater three-dimensional structure at the observation point based on the input underwater acoustic Green's function value. This enables the efficient integration of the Gaussian ray method for calculating the underwater acoustic Green's function value with the existing ship three-dimensional acoustic elasticity analysis software THAFTS-Acoustic.

[0049] The above are merely preferred embodiments of this application, and this application is not limited to the above embodiments. It is understood that other improvements and variations that can be directly derived or conceived by those skilled in the art without departing from the spirit and concept of this application should be considered to be included within the protection scope of this application.

Claims

1. A method for calculating three-dimensional acoustic elasticity in a horizontally non-uniform channel environment, characterized in that, The three-dimensional acoustoelasticity calculation method under horizontally non-uniform channel conditions includes: A finite element model of an underwater three-dimensional structure and a wet surface element mesh model of the corresponding wet surface of the structure are established. Based on the finite element model and the wet surface element mesh model, fluid-structure interaction acoustoelastic calculations are performed to obtain the point sound source intensity of each wet surface element on the wet surface of the structure in the finite element model. Using the Gaussian ray tracing method, based on the various acoustic field environment parameters of the fluid domain in which the underwater three-dimensional structure is located, the underwater acoustic Green function values ​​at the observation points of each wet surface element on the wet surface of the finite element model in a horizontally non-uniform channel environment are calculated; wherein, at least one acoustic field environment parameter in the fluid domain changes along the horizontal direction, forming a horizontally non-uniform channel environment; The sound pressure level of the underwater three-dimensional structure at the observation point is obtained by combining the sound source intensity of each wet surface element on the wet surface element with the water acoustic Green function value at the observation point in a horizontal non-uniform channel environment. The calculation of the underwater acoustic Green function values ​​at observation points on the wetted surface of the finite element model in a horizontally non-uniform channel environment includes: configuring the Bellhop program with parameters according to various acoustic field environment parameters of the fluid domain, the coordinates of the point sound source intensity of each wetted surface element on the wetted surface of the three-dimensional structure, and the coordinates of the observation points. When configuring the Bellhop program with parameters, the sound source information in the Bellhop program is configured according to the coordinates of the observation points based on the principle of acoustic field reciprocity, and the field point information in the Bellhop program is configured according to the coordinates of each wetted surface element on the wetted surface of the finite element model. The Bellhop program is then called to obtain the underwater acoustic Green function values ​​at observation points on the wetted surface of the finite element model in a horizontally non-uniform channel environment.

2. The three-dimensional acoustic elasticity calculation method under a horizontally non-uniform channel environment according to claim 1, characterized in that, The three-dimensional acoustoelasticity calculation method under horizontally non-uniform channel conditions also includes: The Bellhop program is called once at each frequency point within the target frequency range to obtain the underwater acoustic Green function values ​​of all wetted surface elements at the current frequency point in the horizontal non-uniform channel environment. The sound pressure level of the underwater three-dimensional structure at the current frequency point in the horizontal non-uniform channel environment is obtained by superimposing the source intensity of each wetted surface element at the current frequency point.

3. The three-dimensional acoustic elasticity calculation method under a horizontally non-uniform channel environment according to claim 1, characterized in that, At least one acoustic field environmental parameter varies horizontally in the sound velocity profile of the fluid domain where the underwater three-dimensional structure is located and in the seabed topography.

4. The three-dimensional acoustic elasticity calculation method under a horizontally non-uniform channel environment according to claim 1, characterized in that, The superimposed sound pressure level of the underwater three-dimensional structure at the observation point includes: Based on the underwater acoustic Green's function values ​​of each wet surface element on the structured wet surface of the finite element model at the observation points in a horizontally non-uniform channel environment, and combined with the superposition of the point sound source intensity of each wet surface element, the observation points in the horizontally non-uniform channel environment are obtained. The sound field velocity potential at that location : in, The wetted surface element on the structure of the finite element model is the wetted surface element. The sound source is strong. It is a wet noodle. Observation points in a horizontally non-uniform channel environment The Green function value of the underwater acoustic field at that location. The wet surface of the structure in the finite element model. Indicated on the wet surface of the structure Integrate the area on top; Based on observation points in a horizontally non-uniform channel environment The sound field velocity potential at that location The sound pressure level of the underwater three-dimensional structure at the observation point in a horizontally non-uniform channel environment is obtained.

5. A three-dimensional acoustic elasticity calculation device for a horizontally non-uniform channel environment, characterized in that, The three-dimensional acoustoelasticity calculation device under the horizontal non-uniform channel environment includes: The model building module is used to build finite element models of underwater three-dimensional structures and corresponding wet surface element mesh models of the wet surface of the structure. The point sound source intensity calculation module is used to perform fluid-structure interaction acoustoelastic calculations based on the finite element model and the wetted surface element mesh model to obtain the point sound source intensity of each wetted surface element on the wetted surface of the structure of the finite element model. The Green's function calculation module is used to calculate the underwater acoustic Green's function value at the observation point of each wet surface element on the wet surface of the finite element model in a horizontally non-uniform channel environment based on the various acoustic field environment parameters of the fluid domain in which the underwater three-dimensional structure is located, using the Gaussian ray method; wherein, at least one acoustic field environment parameter in the fluid domain changes along the horizontal direction to form a horizontally non-uniform channel environment. The Green's function calculation module is also used to configure the Bellhop program according to various acoustic field environment parameters of the fluid domain, the coordinates of the point sound source intensity of each wet surface element on the structural wet surface of the three-dimensional structure, and the coordinates of the observation point. When configuring the Bellhop program, according to the principle of acoustic field reciprocity, the sound source information in the Bellhop program is configured according to the coordinates of the observation point, and the field point information in the Bellhop program is configured according to the coordinates of each wet surface element on the structural wet surface of the finite element model. The Bellhop program is called to obtain the underwater acoustic Green's function values ​​of all wet surface elements on the structural wet surface of the finite element model at the observation point in a horizontal non-uniform channel environment. The sound propagation calculation module is used to obtain the sound pressure level of the underwater three-dimensional structure at the observation point based on the underwater acoustic Green function value of each wet surface element on the wet surface of the structure at the observation point in a horizontal non-uniform channel environment, combined with the superposition of the point sound source intensity of each wet surface element.

6. The three-dimensional acoustic elasticity calculation device for a horizontally non-uniform channel environment according to claim 5, characterized in that, The Green function calculation module is also used to sequentially traverse each frequency point within the target frequency range and call the Bellhop program once at each frequency point to obtain the underwater acoustic Green function values ​​of all wetted surface elements at the current frequency point in the observation point of the horizontal non-uniform channel environment. The sound propagation calculation module is also used to obtain the sound pressure level of the underwater three-dimensional structure at the observation point in a horizontally non-uniform channel environment at the current frequency point by combining the underwater acoustic Green function values ​​of all wetted surface elements at the observation point with the source intensity of the point sound source of each wetted surface element at the current frequency point.

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