Underwater structure two-dimensional irregular waveguide sound field calculation method, device and medium

Abstract

The invention relates to a calculation method and device for a two-dimensional irregular waveguide sound field of an underwater structure and a medium, and belongs to the technical field of underwater sound radiation forecast.The calculation method for the two-dimensional irregular waveguide sound field of the underwater structure comprises the steps that the two-dimensional irregular waveguide sound field of the underwater structure is constructed; multi-connected domain complex waveguide sound field calculation is converted into single connected domain sound field calculation, the boundary of a waveguide area of a two-dimensional irregular waveguide sound field is determined based on the constructed coordinate system, the boundary comprises an irregular fluctuating seabed boundary, and integration is carried out along the boundary to determine an integral equation; discretizing the boundary of the waveguide region, determining a boundary integral equation based on the basic solution of the integral equation, calculating a coefficient matrix in the constructed linear equation set, and determining an unknown physical quantity on the boundary; the intra-domain integral equation is determined based on the boundary integral equation, the velocity potential function value is determined based on the intra-domain integral equation and the known boundary physical quantity, then the sound pressure of the waveguide region is determined, and the calculation precision of the underwater radiation sound field is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater acoustic radiation prediction, and particularly to a method, device and medium for calculating the sound field of a two-dimensional irregular waveguide of an underwater structure. Background Art

[0002] The prediction of the radiation sound field caused by the vibration of an underwater structure has always been an important issue in the fields of underwater countermeasure and underwater acoustic communication. The characteristics of the underwater radiation sound field not only have a coupling relationship with the dynamics of the structure, but also have a boundary condition constraint relationship and an energy transfer relationship with the underwater environment (the sea surface and the seabed in the waveguide environment) where the structure is located.

[0003] In the traditional theories and methods related to the underwater structure acoustic radiation in an irregular interface waveguide environment, it is mainly based on the premise assumption of an equivalent flat interface with a small roughness. The reflection coefficient of a rough sea surface or seabed is calculated based on methods such as the Kirchhoff assumption or the small slope approximation, and the wave equation is solved by methods such as variable separation, wave number integration or discrete difference to realize the calculation of the radiation sound field of the underwater structure.

[0004] However, the accuracy and applicability of the current calculation methods for the underwater structure acoustic radiation in a rough ocean waveguide interface are limited by the assumption of interface irregularity in the theory, that is, the undulating interface has characteristics such as "micro" and "small". For an irregular seabed topography with a large undulation and a large slope change, the theoretical assumptions of such methods are no longer applicable, resulting in the serious deviation of the predicted results of the radiation sound field from the true value and a significant reduction in the calculation accuracy. Summary of the Invention

[0005] In view of this, it is necessary to provide a method, device and medium for calculating the sound field of a two-dimensional irregular waveguide of an underwater structure to solve the technical problem of poor calculation accuracy of the radiation sound field of an underwater structure in a complex waveguide environment, especially under a large-undulation irregular interface.

[0006] To solve the above problems, the present invention provides a method for calculating the sound field of a two-dimensional irregular waveguide of an underwater structure, including: Construct a two-dimensional irregular waveguide sound field of an underwater structure, determine the boundary of the waveguide region of the two-dimensional irregular waveguide sound field based on the constructed coordinate system, and integrate the boundary to determine an integral equation; After discretizing the boundary of the waveguide region, determine the discretized boundary integral equation based on the fundamental solution of the integral equation; Construct a linear equation system based on the boundary integral equation, calculate the coefficient matrix and the integral term of the linear equation system to determine the unknown physical quantities on the boundary; Determine the integral equation in the domain based on the boundary integral equation, determine the velocity potential function value based on the integral equation in the domain and the known physical quantities on the boundary, and determine the sound pressure in the waveguide region based on the velocity potential function value.

[0007] In a possible implementation, constructing the two-dimensional irregular waveguide sound field of the underwater structure includes: Constructing the two-dimensional irregular waveguide sound field of the underwater structure with the underwater structure as the closed region and the outer surface of the underwater structure, the sea surface interface, and the irregular undulating seabed interface as the waveguide regions.

[0008] In a possible implementation, determining the boundary of the waveguide region of the two-dimensional irregular waveguide sound field based on the constructed coordinate system and integrating the boundary to determine the integral equation includes: Taking the intersection point of the left boundary and the lower boundary of the two-dimensional irregular waveguide sound field as the origin of the coordinate system to construct a two-dimensional Cartesian coordinate system, and determining the boundary of the waveguide region of the two-dimensional irregular waveguide sound field based on the two-dimensional Cartesian coordinate system, where the boundary of the waveguide region at least includes the sea surface boundary, the outer surface boundary of the underwater structure, and the irregular undulating seabed boundary, and the origin of the underwater structure is located at the center of the waveguide region; Connecting the outer surface boundary of the underwater structure and the irregular undulating seabed boundary, after converting the multi-connected domain of the waveguide region into a simply-connected domain, using the boundary integral method to integrate along the boundary of the waveguide region to obtain the integral equation, where the boundary integral loop of the outer surface of the underwater structure is in the clockwise direction, the normal direction is inward with respect to the center of the waveguide region, and the boundary integral loop of the waveguide region is in the counterclockwise direction.

[0009] In a possible implementation, the calculation formula of the integral equation is: , where is the velocity potential function, is the normal derivative of the velocity potential function, is the fundamental solution of the velocity potential function, is the fundamental solution of the normal derivative of the velocity potential function, is the point on the outer surface boundary of the underwater structure, is the point on the irregular undulating seabed boundary, is the outer surface boundary of the underwater structure, is the irregular undulating seabed boundary, is the boundary of the waveguide region, is the change amount of the integral variable.

[0010] In a possible implementation, after discretizing the boundary of the waveguide region, determining the discretized boundary integral equation based on the fundamental solution of the integral equation includes: After discretizing the outer surface boundary of the underwater structure, the irregular undulating seabed boundary, and the sea surface boundary, the discretized boundary integral equation is determined based on the fundamental solution of the integral equation.

[0011] In a possible implementation, the calculation formula of the boundary integral equation is: , where is the velocity potential function, is the normal derivative of the velocity potential function, is the fundamental solution of the velocity potential function, is the fundamental solution of the normal derivative of the velocity potential function, is the number of boundary discretizations, is a positive integer.

[0012] In a possible implementation, the calculation formula of the linear equations is: , where is the integral term coefficient matrix of the velocity potential function, is the integral term coefficient matrix of the normal derivative of the velocity potential function, is at the boundary values of the velocity potential function, is at the boundary values of the normal derivative of the velocity potential function; The calculation formula of the in-domain integral equation is: , where is the velocity potential at the -th point in the waveguide region, is the -th element of the velocity potential function on the boundary, is the element in the -th row and -th column of the velocity potential function coefficient matrix, is the -th element of the normal derivative of the velocity potential function on the boundary, is the element in the -th row and -th column of the normal derivative coefficient matrix of the velocity potential function, is the number of boundary discretizations.

[0013] In a possible implementation, the calculation formula of the sound pressure in the waveguide region is: , where is the sound pressure, is the imaginary unit, is the sound field density, is the circular frequency, is the velocity potential function in the waveguide region.

[0014] On the other hand, the present invention also provides an electronic device, including: a processor and a memory; A computer-readable program executable by the processor is stored on the memory; When the processor executes the computer-readable program, the steps in the above-mentioned underwater structure two-dimensional irregular waveguide sound field calculation method are implemented.

[0015] On the other hand, the present invention also provides a computer-readable storage medium. The computer-readable storage medium stores one or more programs, and the one or more programs can be executed by one or more processors to implement the steps in the above-mentioned underwater structure two-dimensional irregular waveguide sound field calculation method.

[0016] The beneficial effects of the present invention are as follows: construct the two-dimensional irregular waveguide sound field of the underwater structure, determine the boundary of the waveguide region of the two-dimensional irregular waveguide sound field based on the constructed coordinate system, and determine the integral equation by integrating the boundary; after discretizing the boundary of the waveguide region, determine the discretized boundary integral equation based on the fundamental solution of the integral equation; construct a linear equation set based on the boundary integral equation, calculate the coefficient matrix and integral terms of the linear equation set to determine the unknown physical quantities on the boundary; determine the domain integral equation based on the boundary integral equation, determine the velocity potential function value based on the domain integral equation and the unknown physical quantities, determine the sound pressure in the waveguide region based on the velocity potential function value, convert the complex multi-connected domain problem of sound radiation in the underwater waveguide environment structure into a single-connected domain sound field boundary value problem of the structure-aqueous sound field, and given the boundary conditions of the outer surface of the structure, the sea surface, and the seabed, realize the irregular self-adaptation of the seabed interface and improve the calculation accuracy of the underwater radiation sound field. Description of the Drawings

[0017] Figure 1 is a flowchart of an embodiment of the underwater structure two-dimensional irregular waveguide sound field calculation method provided by the present invention; Figure 2 is a schematic diagram of the coordinate system of the two-dimensional radiation sound field of the underwater structure two-dimensional irregular waveguide sound field calculation method provided by the present invention; Figure 3 is a result diagram of the finite element calculation of the underwater structure two-dimensional irregular waveguide sound field calculation method provided by the present invention; Figure 4 is a calculation result diagram of the underwater structure two-dimensional radiation sound field of the underwater structure two-dimensional irregular waveguide sound field calculation method provided by the present invention; Figure 5Schematic diagram of a structure of an embodiment of the electronic device provided by the present invention. Detailed implementation manners

[0018] The preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings. The accompanying drawings form a part of this application and are used together with the embodiments of the present invention to explain the principles of the present invention, rather than to limit the scope of the present invention.

[0019] The present invention discloses a method, device and medium for calculating the two-dimensional irregular waveguide sound field of an underwater structure, which can be used in a computer. The method, device or computer-readable storage medium involved in the present invention can either be integrated with the above device or be relatively independent.

[0020] A specific embodiment of the present invention discloses a method for calculating the two-dimensional irregular waveguide sound field of an underwater structure, which can be executed by a computer, specifically by one or more processors of the computer. As Figure 1 shown, the method for calculating the two-dimensional irregular waveguide sound field of an underwater structure includes: S101. Construct a two-dimensional irregular waveguide sound field of an underwater structure, determine the boundary of the waveguide region of the two-dimensional irregular waveguide sound field based on the constructed coordinate system, and perform integration on the boundary to determine the integral equation; S102. After discretizing a part of the boundary of the waveguide region, determine the discretized boundary integral equation based on the fundamental solution of the integral equation; S103. Construct a linear equation system based on the boundary integral equation, calculate the coefficient matrix and the integral term of the linear equation system, and determine the unknown physical quantities on the boundary; S104. Determine the integral equation in the domain based on the boundary integral equation, determine the velocity potential function value based on the integral equation in the domain and the known physical quantities on the boundary, and determine the sound pressure in the waveguide region based on the velocity potential function value.

[0021] Among them, the waveguide region of the two-dimensional irregular waveguide sound field (two-dimensional radiation sound field) is a multi-connected domain. After connecting the outer surface boundary of the structure and the irregularly undulating seabed boundary, the multi-connected domain is transformed into a simply-connected domain, realizing the conversion of the sound field calculation problem, improving the calculation efficiency, and ensuring the accuracy of the calculation result.

[0022] Compared with the prior art, the method for calculating the two-dimensional irregular waveguide sound field of an underwater structure provided in this embodiment constructs a two-dimensional irregular waveguide sound field of the underwater structure, determines the boundary of the waveguide region of the two-dimensional irregular waveguide sound field based on the constructed coordinate system, integrates the boundary to determine the integral equation; after discretizing the boundary of the waveguide region, determines the discretized boundary integral equation based on the fundamental solution of the integral equation; constructs a linear equation system based on the boundary integral equation, calculates the coefficient matrix and the integral terms of the linear equation system to determine the unknown physical quantities on the boundary; determines the in-domain integral equation based on the boundary integral equation, determines the velocity potential function value based on the in-domain integral equation and the known physical quantities on the boundary, determines the sound pressure in the waveguide region based on the velocity potential function value, converts the problem of the multi-connected domain of sound radiation of a complex seabed waveguide environment structure into a boundary value problem of a single-connected domain of the structure-aqueous sound field, and given the boundary conditions of the outer surface of the structure, the sea surface, and the seabed, realizes irregular self-adaptation to the seabed interface, and improves the calculation accuracy of the underwater radiation sound field.

[0023] In some embodiments, in step S101, a two-dimensional irregular waveguide sound field of an underwater structure is constructed. Taking the underwater structure as a closed region and the outer surface of the underwater structure, the sea surface interface, and the irregularly undulating seabed interface as the waveguide region, a two-dimensional irregular waveguide sound field of the underwater structure is constructed, that is, a two-dimensional radiation sound field. Among them, the underwater structure is a spherical shell. Determine the boundary of the waveguide region of the two-dimensional irregular waveguide sound field based on the constructed coordinate system. Construct a two-dimensional Cartesian coordinate system with the intersection point of the left boundary and the lower boundary of the two-dimensional irregular waveguide sound field as the origin of the coordinate system. Determine the boundary of the waveguide region of the two-dimensional irregular waveguide sound field based on the two-dimensional Cartesian coordinate system. Among them, the boundary of the waveguide region at least includes the sea surface boundary, the outer surface boundary of the underwater structure, and the irregularly undulating seabed boundary. The origin of the underwater structure is located at the center of the waveguide region. For the schematic diagram of the coordinate system of its two-dimensional radiation sound field, please refer to Figure 2 , such as Figure 2 shown, the underwater structure located in the waveguide environment is used as a closed region , and has a convex outer surface. The outer surface of the structure, the sea surface interface, and the seabed interface together constitute the waveguide region , obtain the known parameters of the waveguide environment and the underwater structure, including the boundary coordinates of the outer surface of the structure, the boundary coordinates of the irregularly undulating seabed, the boundary coordinates of the sea surface, and the boundary of the domain formed by them, the sound field parameters, and the corresponding boundary conditions of the boundary. The spherical shell radius of the underwater structure is 2 meters. The minimum distance between the sea surface and the seabed is 100 meters, and the maximum distance is 120 meters. The seabed boundary is a downward undulating boundary. The origin of the structure is located at the center of the calculation domain , the fluid density is , the sound speed is , the frequency of the simple harmonic sound field is 20 Hz; the sea surface simulates an absolutely soft boundary condition with a velocity potential value of 0, the seabed simulates an absolutely hard boundary condition with a normal derivative of the velocity potential value of 0, and the velocity potential value on the outer surface of the structure is 0.01.

[0024] Integrate the boundary to determine the integral equation. After connecting the outer surface boundary of the underwater structure with the irregular undulating seabed boundary, use the boundary integral method to integrate the boundary of the waveguide region to determine the integral equation. Among them, the boundary integral loop on the outer surface of the underwater structure is in the clockwise direction, the center of the waveguide region is in the direction of the normal inward, and the boundary integral loop of the waveguide region is in the counterclockwise direction. The waveguide region can be regarded as a multiply connected domain, and its inner and outer boundaries are the outer surface boundary of the structure , the irregular undulating seabed boundary , the sea surface boundary . At the boundary and the boundary , arbitrarily take two points B and A respectively, and use an arbitrary curve connecting A and B to convert the multiply connected domain of the waveguide environment region and the internal region of the structure into a simply connected domain. Use the boundary integral method to integrate the boundary of the waveguide region . When integrating, the boundary integral loop of the structure is in the clockwise direction, and the boundary integral loop of the waveguide environment composed of the sea surface and the seabed is in the counterclockwise direction. The calculation formula of its integral equation is: , where, is the velocity potential function, is the normal derivative of the velocity potential function, is the fundamental solution of the velocity potential function, is the fundamental solution of the normal derivative of the velocity potential function, is the point on the outer surface boundary of the underwater structure, is the point on the irregular undulating seabed boundary, is the outer surface boundary of the underwater structure, is the irregular undulating seabed boundary, is the boundary of the waveguide region, is the change amount of the integral variable.

[0025] In some embodiments, in step S102, after discretizing the boundary of the waveguide region, determine the discretized boundary integral equation based on the fundamental solution of the integral equation. For the fundamental solution of the Helmholtz equation of the waveguide environment with an irregular undulating seabed boundary in a two-dimensional shallow sea, that is, the fundamental solution of the integral equation, the calculation formula of its fundamental solution is: , where, is the fundamental solution of the Helmholtz equation, is the imaginary unit, is the Hankel function of the second kind of order zero, is the acoustic wavenumber, is the two-dimensional spatial 2-norm; Since the fundamental solution automatically satisfies the Sommerfeld radiation condition, there is no need to discretize the left and right boundaries of the waveguide environment. Only the outer surface boundary of the structure, the irregular undulating seabed boundary, and the sea surface boundary need to be discretized. The outer surface boundary of the structure , the irregular undulating seabed boundary and the sea surface boundary are discretized. In this process, any shaped seabed is automatically divided into multiple boundary elements. The outer surface boundary of the structure in the waveguide region , the irregular undulating seabed boundary , the sea surface boundary are discretized. The outer surface boundary of the structure is divided into boundary elements through discretization. The irregular undulating seabed boundary is divided into boundary elements through discretization. The sea surface boundary is divided into boundary elements through discretization. The midpoint of the boundary element is taken as the node. The total number of boundary elements is , where boundary elements belong to the outer surface boundary of the structure , , boundary elements belong to the irregular seabed boundary , boundary elements belong to the sea surface boundary . The constant element is adopted, and the node is taken at the midpoint of the boundary element. Based on the fundamental solution of the integral equation, the boundary integral equation on the discretized smooth boundary is obtained. The calculation formula of its boundary integral equation is: , where is the velocity potential function, is the normal derivative of the velocity potential function, is the fundamental solution of the velocity potential function, is the fundamental solution of the normal derivative of the velocity potential function, is the number of boundary discretizations, is a positive integer.

[0026] In some embodiments, in step S103, a linear equation system is constructed based on the boundary integral equation, the coefficient matrix and the integral terms of the linear equation system are calculated, the unknown physical quantities on the boundary are determined, and the unknown physical quantities on the boundary are obtained through the boundary integral equation velocity potential function values and normal derivative values of the velocity potential function, and the linear equation system in the form of a matrix vector is formed by velocity potential function values and normal derivative values of the velocity potential function on the boundary. The calculation formula of the linear equation system is: , where is the integral term coefficient matrix of the velocity potential function, is the integral term coefficient matrix of the normal derivative of the velocity potential function, is velocity potential function values on the boundary, is normal derivative values of the velocity potential function on the boundary; The calculation formula of the matrix elements in the linear equation system is: , , , , where , are matrices, , are the subscripts of the -th row and the -th column in the matrix, is the Kronecker operator. When , is 0. When , is 1, is the integral of the normal derivative of the velocity potential function; The coefficient matrix and the integral terms of the linear equation system are calculated to determine the unknown physical quantities on the boundary. The unknown physical quantities are: all unknown velocity potential function values and normal derivative values on the outer surface boundary of the structure, the seabed boundary and the sea surface boundary ; the integral terms in the linear equation system are calculated by Gaussian integration. The integral terms include: , , Among them, is the Hankel function of the second kind of order 0, is the acoustic wave number, is the two-dimensional space 2-norm, is the Hankel function of the second kind of order 1. After organizing the integral term, we get: , , Among them, is the point and the point 's 2-norm, is the dimensionless coordinate; The quadrature formula used for Gaussian integration is: , Among them, is the quadrature point of the Gaussian quadrature method, , the quadrature point is the distinct real roots of the Legendre polynomial of degree is taken as 6, which holds precisely for any polynomial not exceeding degree 11. Through the known boundary conditions, all unknown velocity potential function values and the normal derivative values of the velocity potential function values are obtained by using the direct inversion method.

[0027] In some embodiments, in step S104, based on the boundary integral equation, the domain integral equation is determined, and the calculation formula of the domain integral equation is: , Among them, is the velocity potential at the th point in the waveguide region, is the th element of the velocity potential function on the boundary, is the element in the th row and th column of the velocity potential function coefficient matrix, is the th element of the normal derivative of the velocity potential function on the boundary, is the element in the th row and th column of the normal derivative coefficient matrix of the velocity potential function, is the number of boundary discretizations; Based on the domain integral equation and the known physical quantities on the boundary, the velocity potential function values are determined, and the outer surface boundary , the seabed boundary and the sea surface boundary Substitute all known values of the velocity potential function and the normal derivative values into the integral equation within the domain to calculate the velocity potential function values in the waveguide region. Based on the velocity potential function values, determine the sound pressure in the waveguide region. The calculation formula for the sound pressure in the waveguide region is as follows: , where, is the sound pressure, is the imaginary unit, is the sound field density, is the circular frequency, is the velocity potential function in the waveguide region.

[0028] For the result graph calculated using the finite element method, please refer to Figure 3 , and for the calculation result graph of the two-dimensional irregular waveguide sound field of the underwater structure, please refer to Figure 4 . Through Figure 3 compared with Figure 4 , it can be seen from the comparison that compared with the finite element method of the same model, for the sound radiation problem of underwater structures in a waveguide environment with an irregular seabed, using the calculation of the two-dimensional irregular waveguide sound field of the underwater structure has higher accuracy, and because only the boundary is discretized and calculated, the calculation efficiency is higher.

[0029] Abstract and equivalently transform the multi-connected domain problem of sound radiation of underwater structures in a waveguide environment into a boundary value problem of single-connected domain sound field calculation. Based on the discretization and calculation of the boundary integral equation, it realizes the adaptability to the boundary shape of the irregular seabed interface, can fully solve the problem of any irregularly shaped seabed interface, improves the applicability of the calculation and prediction method for sound radiation of underwater structures, and has higher accuracy and efficiency.

[0030] As Figure 5 shown, the present invention also correspondingly provides an electronic device 500. The electronic device 500 can be a computing device such as a mobile terminal, a desktop computer, a notebook, a handheld computer, and a server. The electronic device 500 includes a processor 501, a memory 502, and a display 503. Figure 5 Only some components of the electronic device 500 are shown. However, it should be understood that it is not required to implement all the shown components, and more or fewer components can be implemented alternatively.

[0031] The memory 502 may be an internal storage unit of the electronic device 500 in some embodiments, such as the hard disk or memory of the electronic device 500. The memory 502 may also be an external storage device of the electronic device 500 in other embodiments, such as a plug-in hard disk equipped on the electronic device 500, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. Further, the memory 502 may also include both the internal storage unit of the electronic device 500 and the external storage device. The memory 502 is used to store application software installed on the electronic device 500 and various types of data, such as program codes installed on the electronic device 500. The memory 502 may also be used to temporarily store data that has been output or will be output. In one embodiment, a two-dimensional irregular waveguide sound field calculation program for underwater structures is stored on the memory 502, and the two-dimensional irregular waveguide sound field calculation program for underwater structures can be executed by the processor 501, so as to implement the two-dimensional irregular waveguide sound field calculation method for underwater structures in various embodiments of the present invention.

[0032] The processor 501 may be a central processing unit (CPU), a microprocessor or other data processing chips in some embodiments, and is used to run the program codes stored in the memory 502 or process data, such as the two-dimensional irregular waveguide sound field calculation method for underwater structures.

[0033] The display 503 may be an LED display, a liquid crystal display, a touch liquid crystal display, and an OLED (Organic Light-Emitting Diode) toucher, etc. in some embodiments. The display 503 is used to display the identification information of the two-dimensional irregular waveguide sound field calculation program for underwater structures and to display a visual user interface. The components 501-503 of the electronic device 500 communicate with each other through a system bus.

[0034] In some embodiments, when the processor 501 executes the two-dimensional irregular waveguide sound field calculation program in the memory 502, each step in the two-dimensional irregular waveguide sound field calculation method described in the above embodiments is implemented. Since the two-dimensional irregular waveguide sound field calculation method has been described in detail above, it will not be repeated here.

[0035] Correspondingly, the present invention also provides a computer-readable storage medium accordingly. The computer-readable storage medium is used to store computer-readable programs or instructions. When the programs or instructions are executed by a processor, the steps or functions in the two-dimensional irregular waveguide sound field calculation method provided in the above method embodiments can be implemented.

[0036] In summary, the method, device and medium for calculating the two-dimensional irregular waveguide sound field of an underwater structure provided by the present invention construct the two-dimensional irregular waveguide sound field of the underwater structure, convert the calculation of the complex waveguide sound field in a multi-connected domain into the calculation of the sound field in a simply-connected domain, determine the boundary of the waveguide region of the two-dimensional irregular waveguide sound field based on the constructed coordinate system, including the irregular undulating seabed boundary, and determine the integral equation by integrating the boundary; after discretizing the boundary of the waveguide region, determine the discretized boundary integral equation based on the fundamental solution of the integral equation; construct a linear system of equations based on the boundary integral equation, calculate the coefficient matrix and integral terms of the linear system of equations, and determine the unknown physical quantities on the boundary; determine the integral equation in the domain based on the boundary integral equation, determine the velocity potential function value based on the integral equation in the domain and the known physical quantities on the boundary, and determine the sound pressure in the waveguide region based on the velocity potential function value, thereby improving the calculation accuracy of the underwater radiation sound field.

[0037] Those skilled in the art can understand that all or part of the processes for implementing the methods of the above embodiments can be completed by instructing relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium. Among them, the computer-readable storage medium is a magnetic disk, an optical disk, a read-only memory or a random access memory, etc.

[0038] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

Claims

1. A method for calculating the acoustic field of a two-dimensional irregular waveguide of an underwater structure, characterized in that: include: Constructing a two-dimensional irregular waveguide acoustic field of an underwater structure, determining a boundary of a waveguide region of the two-dimensional irregular waveguide acoustic field based on the constructed coordinate system, and integrating the boundary to determine an integral equation; After discretizing the boundary of the waveguide region, determining a discretized boundary integral equation based on a basic solution of the integral equation; Constructing a linear equation system based on the boundary integral equation, calculating the coefficient matrix and integral terms of the linear equation system, and determining unknown physical quantities on the boundary; An integral equation within a domain is determined based on the boundary integral equation, a velocity potential function value is determined based on the integral equation within the domain and known physical quantities at the boundary, and a sound pressure in a waveguide region is determined based on the velocity potential function value.

2. The method for calculating the acoustic field of a two-dimensional irregular waveguide of an underwater structure according to claim 1, characterized in that: The method of constructing a two-dimensional irregular waveguide acoustic field of an underwater structure comprises: A two-dimensional irregular waveguide acoustic field of the underwater structure is constructed with the underwater structure as a closed area and the outer surface of the underwater structure, the sea surface interface and the irregular undulating seabed interface as the waveguide area.

3. The method for calculating the acoustic field of a two-dimensional irregular waveguide of an underwater structure according to claim 2, characterized in that: Determining the boundary of the waveguide region of the two-dimensional irregular waveguide acoustic field based on the constructed coordinate system, and integrating the boundary to determine the integral equation, comprises: A two-dimensional Cartesian coordinate system is constructed with the intersection of the left boundary and the lower boundary of the two-dimensional irregular waveguide acoustic field as the origin of the coordinate system, and the boundary of the waveguide area of ​​the two-dimensional irregular waveguide acoustic field is determined based on the two-dimensional Cartesian coordinate system, wherein the boundary of the waveguide area at least includes a sea surface boundary, an outer surface boundary of an underwater structure, and an irregular undulating seabed boundary, and the origin of the underwater structure is located at the center of the waveguide area; The outer surface boundary of the underwater structure is connected to the irregular undulating seabed boundary, and after the multiply connected domain of the waveguide area is converted into a simply connected domain, the boundary integral method is used to integrate along the boundary of the waveguide area to obtain an integral equation, wherein the boundary integral loop of the outer surface of the underwater structure is in the clockwise direction, the center of the waveguide area is in the normal inward direction, and the boundary integral loop of the waveguide area is in the counterclockwise direction.

4. The method for calculating the acoustic field of a two-dimensional irregular waveguide of an underwater structure according to claim 3, characterized in that: The integral equation is calculated as follows: ， in, is the velocity potential function, is the normal derivative of the velocity potential function, is the basic solution of the velocity potential function, is the basic solution of the normal derivative of the velocity potential function, is a point on the outer surface boundary of the underwater structure, is a point on the boundary of the irregular undulating seabed, is the outer surface boundary of the underwater structure, It is an irregular undulating seabed boundary. is the boundary of the waveguide region, is the change in the integral variable.

5. The method for calculating the acoustic field of a two-dimensional irregular waveguide of an underwater structure according to claim 3, characterized in that: After discretizing the boundary of the waveguide region, determining the discretized boundary integral equation based on the basic solution of the integral equation includes: After discretizing the outer surface boundary of the underwater structure, the irregular undulating seabed boundary and the sea surface boundary, the discretized boundary integral equation is determined based on the basic solution of the integral equation.

6. The method for calculating the acoustic field of a two-dimensional irregular waveguide of an underwater structure according to claim 5, characterized in that: The calculation formula of the boundary integral equation is: ， in, is the velocity potential function, is the normal derivative of the velocity potential function, is the basic solution of the velocity potential function, is the basic solution of the normal derivative of the velocity potential function, is the boundary discrete quantity, Is a positive integer.

7. The method for calculating the acoustic field of a two-dimensional irregular waveguide of an underwater structure according to claim 5, characterized in that: The calculation formula of the linear equation system is: ， in, is the integral coefficient matrix of the velocity potential function, is the integral coefficient matrix of the normal derivative of the velocity potential function, For on the border The velocity potential function value, For on the border The value of the normal derivative of the velocity potential function; The calculation formula of the integral equation in the domain is: ， in, is the first The velocity potential of a point, is the velocity potential function on the boundary elements, is the first Line Column elements, is the normal derivative of the velocity potential function on the boundary elements, is the first in the normal derivative coefficient matrix of the velocity potential function Line Column elements, is the boundary discrete quantity.

8. The method for calculating the acoustic field of a two-dimensional irregular waveguide of an underwater structure according to claim 7, characterized in that: The calculation formula for the sound pressure in the waveguide area is: ， in, is the sound pressure, is an imaginary unit, is the sound field density, is the circular frequency, is the velocity potential function in the waveguide region.

9. An electronic device, characterized in that: including memory and processor; The memory stores a computer-readable program executable by the processor; When the processor executes the computer-readable program, the steps in the method for calculating the two-dimensional irregular waveguide acoustic field of an underwater structure as described in any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores one or more programs, and the one or more programs can be executed by one or more processors to implement the steps in the method for calculating the two-dimensional irregular waveguide acoustic field of an underwater structure as described in any one of claims 1-8.

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