Method and system for calculating high-frequency noise of underwater vehicle based on fluid compressibility

Abstract

This invention discloses a method and system for calculating high-frequency noise of underwater vehicles based on fluid compressibility. The method includes: obtaining the local static pressure of the flow field; calculating the density distribution of the compressible water flow based on the local static pressure and the compressibility characteristics of the water; constructing a flow control equation considering fluid compressibility based on the density distribution of the compressible water flow, and solving the velocity distribution, pressure distribution, and density fluctuation distribution of the flow field through numerical iteration; constructing the FW-H equation based on the density distribution, velocity distribution, pressure distribution, and density fluctuation distribution of the compressible water flow; and embedding the flow control equation and the FW-H equation considering fluid compressibility into a computational fluid dynamics solver for solving, thereby obtaining the high-frequency noise calculation results of the underwater vehicle. This invention can effectively control the high-frequency noise rise phenomenon and improve the accuracy of high-frequency noise prediction for underwater vehicles.

Description

Technical Field

[0001] This invention relates to the field of underwater vehicle noise prediction technology, and in particular to a method, system, storage medium, and electronic device for calculating high-frequency noise of underwater vehicles based on fluid compressibility. Background Technology

[0002] High-frequency noise (above 1kHz) is a core factor affecting the acoustic stealth performance of underwater vehicles. It mainly originates from hydrodynamic mechanisms such as high-frequency pulsating pressure in the boundary layer and high-frequency disturbances in turbulence, which directly affect the stealth of the vehicle and the stability of underwater communication.

[0003] Existing numerical prediction methods for underwater vehicle noise are mostly based on incompressible simulation frameworks. These methods have significant drawbacks when dealing with high-frequency noise: the incompressibility assumption ignores the dynamic changes in fluid density with pressure, and cannot accurately capture the generation mechanism of high-frequency pulsating pressure, resulting in an "upward tilt" phenomenon in the calculation results of high-frequency noise (especially above 1kHz), which seriously restricts the simulation accuracy of high-frequency noise of underwater vehicles. Summary of the Invention

[0004] This invention provides a method, system, storage medium, and electronic device for calculating high-frequency noise of underwater vehicles based on fluid compressibility, which can effectively control the high-frequency noise rise phenomenon and improve the accuracy of high-frequency noise prediction for underwater vehicles.

[0005] This invention provides a method for calculating high-frequency noise of underwater vehicles based on fluid compressibility, including: Obtain the local static pressure of the flow field, and calculate the density distribution of the compressible water flow based on the local static pressure of the flow field and the compressibility characteristics of the water body; Based on the density distribution of the compressible water flow, a water flow control equation considering fluid compressibility is constructed, and the velocity distribution, pressure distribution, and density fluctuation distribution of the flow field are solved by numerical iteration. Based on the density distribution of the compressible water flow, the velocity distribution of the flow field, the pressure distribution of the flow field, and the density fluctuation distribution of the flow field, the FW-H equation is constructed. The flow control equations considering fluid compressibility and the FW-H equations are incorporated into a computational fluid dynamics solver for solving, resulting in calculations of high-frequency noise from underwater vehicles.

[0006] Furthermore, according to the above-mentioned method for calculating high-frequency noise of underwater vehicles based on fluid compressibility, the density distribution of compressible water flow is calculated using the following formula:

[0007] in, For compressible fluid density distribution, This refers to the density of water under saturated conditions. For static pressure in the flow field, The reference pressure is the standard atmosphere. and It is a constant.

[0008] Furthermore, according to the above-mentioned method for calculating high-frequency noise of underwater vehicles based on fluid compressibility, the water flow control equation considering fluid compressibility is as follows:

[0009]

[0010] in, For time, It is a velocity vector. For Hamiltonian operators, For viscous stress tensor, It is a volume force vector. It is the hydrostatic pressure of the fluid.

[0011] Furthermore, according to the above-mentioned method for calculating high-frequency noise of underwater vehicles based on fluid compressibility, the formula for calculating the volume force vector is as follows:

[0012] in, It is the acceleration due to gravity. It is the unit vector in the z-direction.

[0013] Furthermore, according to the above-mentioned method for calculating high-frequency noise of underwater vehicles based on fluid compressibility, the FW-H equation is solved in integral form to obtain the radiated sound pressure. A closed integral surface is selected, formed by the underwater vehicle surface and the virtual surface of the far-field flow field. The FW-H equation is:

[0014] in, As observation point At any moment The radiated sound pressure pressure pulsation at the location; The source point position vector on the integral surface; The distance from the observation point to the source point of the integral surface. Let be the unit direction vector from the source point to the observation point, and let its _____ be the _____. Each component is denoted as ; Let be the instantaneous density of the fluid on the integral surface; The reference density is for a stationary medium. Let be the instantaneous pressure of the fluid on the integral surface; The reference pressure for the static medium; Let be the fluid velocity vector, and its ______ Each component is denoted as ; Let be the velocity vector of the integral surface, and its ... Each component is denoted as ; Let be the outward normal unit vector of the integral surface, and let its be... Each component is denoted as ; This represents the component of the fluid velocity in the direction normal to the integral surface; This represents the component of the velocity on the integral surface in the normal direction of the integral surface; The speed of sound in a stationary medium; The Mach number vector of the integral surface motion is defined as follows: , its first Each component is ; For the Mach number of the integral surface motion in the radial direction Projection on; For the generalized stress tensor form on the penetration integral surface; For Kronecker delta notation, when The value is 1 if the condition is met, otherwise it is 0. It is the viscous stress tensor; The delay time; symbol Indicates the integrand in the lag time Values ​​are taken at the specified location; symbol Indicates the distance of radiation The partial derivative operation.

[0015] Furthermore, according to the above-mentioned method for calculating high-frequency noise of underwater vehicles based on fluid compressibility, the flow control equation considering fluid compressibility and the FW-H equation are embedded into a computational fluid dynamics solver for solving, resulting in the calculation results of high-frequency noise of the underwater vehicle, including: The flow control equations considering fluid compressibility and the FW-H equations were written into a C language file, compiled using Visual Studio, and solved in the computational fluid dynamics solver to obtain the calculation results of high-frequency noise of the underwater vehicle.

[0016] Furthermore, according to the above-mentioned method for calculating high-frequency noise of underwater vehicles based on fluid compressibility, the method further includes: The SIMPLEC algorithm is used to couple pressure and velocity, with a time step of 0.5° per propeller rotation.

[0017] The present invention also provides a high-frequency noise calculation system for underwater vehicles based on fluid compressibility, comprising: The compressible water flow density distribution calculation module is used to obtain the local static pressure of the flow field and calculate the density distribution of the compressible water flow based on the local static pressure of the flow field and the compressibility characteristics of the water body. The water flow control equation construction module is used to construct water flow control equations that consider fluid compressibility based on the density distribution of the compressible water flow, and to solve the velocity distribution, pressure distribution and density fluctuation distribution of the flow field through numerical iteration. The FW-H equation construction module constructs the FW-H equation based on the density distribution of the compressible water flow, the velocity distribution of the flow field, the pressure distribution of the flow field, and the density fluctuation distribution of the flow field. The underwater vehicle high-frequency noise solution module is used to embed the water flow control equation considering fluid compressibility and the FW-H equation into the computational fluid dynamics solver for solving, and obtain the calculation results of the underwater vehicle high-frequency noise.

[0018] The present invention also provides a computer-readable storage medium storing a plurality of instructions adapted for loading by a processor to execute any of the above-described methods for calculating high-frequency noise of underwater vehicles based on fluid compressibility.

[0019] The present invention also provides an electronic device, including a processor and a memory, wherein the processor is electrically connected to the memory, the memory is used to store instructions and data, and the processor is used in the steps of the above-described method for calculating high-frequency noise of underwater vehicles based on fluid compressibility.

[0020] This invention provides a method, system, storage medium, and electronic device for calculating high-frequency noise in underwater vehicles based on fluid compressibility. The invention employs compressible water flow modeling, accurately capturing the generation and propagation characteristics of high-frequency pulsating pressure through dynamic density calculation and complete control equations, thus overcoming the physical model defects caused by the incompressibility assumption. This invention achieves deep coupling between the compressible flow field and the FW-H equations, enabling quantitative prediction of the high-frequency noise radiation characteristics of underwater vehicles and providing reliable numerical support for high-frequency noise reduction design. The calculation model provided by this invention has strong versatility, applicable to different types of underwater vehicles (submarines, torpedoes, etc.) and different high-frequency operating conditions, and is easily developed for engineering applications through secondary development using computational fluid dynamics solvers. Attached Figure Description

[0021] The technical solution and other beneficial effects of the present invention will become apparent from the following detailed description of specific embodiments of the invention, in conjunction with the accompanying drawings.

[0022] Figure 1A flowchart illustrating a high-frequency noise calculation method for underwater vehicles based on fluid compressibility, provided for embodiments of the present invention.

[0023] Figure 2 The density distribution provided in the embodiments of the present invention.

[0024] Figure 3 Comparison of simulation results of hydrodynamic noise of underwater vehicles with propellers using two methods provided in the embodiments of the present invention.

[0025] Figure 4 A schematic diagram of the structure of a high-frequency noise calculation system for underwater vehicles based on fluid compressibility, provided in an embodiment of the present invention.

[0026] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] This invention provides a method, system, storage medium, and electronic device for calculating high-frequency noise of underwater vehicles based on fluid compressibility. The high-frequency noise calculation system for underwater vehicles provided by this invention can be integrated into an electronic device, such as a terminal or server. The terminal can include a tablet computer, laptop computer, personal computer (PC), microprocessor box, or other devices.

[0029] Please see Figure 1 , Figure 1 A flowchart illustrating a high-frequency noise calculation method for underwater vehicles based on fluid compressibility, provided in an embodiment of the present invention, is shown. This method, applied in electronic devices, includes the following steps: S1: Obtain the local static pressure of the flow field. Based on the local static pressure of the flow field and the compressibility characteristics of the water body, calculate the density distribution of the compressible water flow.

[0030] Specifically, the density distribution of compressible water flow is calculated using the following formula:

[0031] in, For compressible fluid density distribution, The density of water under saturation is 998 kg / m3. For static pressure in the flow field, The reference pressure is the standard atmosphere. and It is a constant (in a specific embodiment, it can be 2.2 × 10⁹ Pa and 7.1 respectively).

[0032] S2, based on the density distribution of compressible water flow, constructs the water flow control equation considering the compressibility of the fluid, and solves the velocity distribution, pressure distribution and density fluctuation distribution of the flow field through numerical iteration.

[0033] Considering the fluid compressibility, the governing equations for water flow are shown below, accurately characterizing the coupling simulation of pulsation and noise:

[0034]

[0035] in, For time, the unit is ; It is a velocity vector, with units of . ; For Hamiltonian operators; This is the viscous stress tensor, in units of... ; This is a volume force vector, with units of . For single-phase water flow, the volume force is mainly gravity, that is... , Let be the acceleration due to gravity, taken as 9.81. , It is the unit vector in the z-direction. It is the hydrostatic pressure of the fluid.

[0036] At each time step, the velocity distribution, pressure distribution, and density fluctuation distribution of the flow field can be obtained by iteratively solving the governing equations that take into account the compressibility of the fluid.

[0037] S3. Based on the density distribution, velocity distribution, pressure distribution, and density fluctuation distribution of compressible water flow, the FW-H equation (Fowcs Williams - Hawkings equation) is constructed.

[0038] The FW-H equations are solved in integral form for radiated sound pressure. A closed integral surface is chosen, consisting of the underwater vehicle surface and a virtual surface representing the far-field flow field. The FW-H equations are:

[0039] in, As observation point At any moment The radiated sound pressure pressure pulsation at the location; The source point position vector on the integral surface; The distance from the observation point to the source point of the integral surface. Let be the unit direction vector from the source point to the observation point, and let its _____ be the _____. Each component is denoted as ; Let be the instantaneous density of the fluid on the integral surface; The reference density is for a stationary medium. Let be the instantaneous pressure of the fluid on the integral surface; The reference pressure for the static medium; Let be the fluid velocity vector, and its ______ Each component is denoted as ; Let be the velocity vector of the integral surface, and its ... Each component is denoted as ; Let be the outward normal unit vector of the integral surface, and let its be... Each component is denoted as ; This represents the component of the fluid velocity in the direction normal to the integral surface; This represents the component of the velocity on the integral surface in the normal direction of the integral surface; The speed of sound in a stationary medium; The Mach number vector of the integral surface motion is defined as follows: , its first Each component is ; For the Mach number of the integral surface motion in the radial direction Projection on; For the generalized stress tensor form on the penetration integral surface; For Kronecker delta notation, when The value is 1 if the condition is met, otherwise it is 0. It is the viscous stress tensor; The delay time; symbol Indicates the integrand in the lag time Values ​​are taken at the specified location; symbol Indicates the distance of radiation The partial derivative operation.

[0040] S4 incorporates the flow control equations and FW-H equations, which consider the compressibility of the fluid, into the computational fluid dynamics solver to obtain the calculation results of high-frequency noise of the underwater vehicle.

[0041] Specifically, the flow control equations and FW-H equations considering fluid compressibility are written into a C language file and compiled using Visual Studio. The solution is obtained by calling a user-defined function (UDF) in the computational fluid dynamics solver, thus achieving the coupled simulation of compressible flow field and high-frequency noise, and effectively suppressing the upward tilting phenomenon in high-frequency noise calculation.

[0042] In this embodiment of the invention, the finite volume method is used to discretize the governing equations; a high-quality hexahedral mesh is used to spatially discretize the computational domain, with a total mesh count of approximately 30 million. Velocity inlet and pressure outlet boundary conditions are used, and the computational domain walls are set as no-slip boundary conditions. The SIMPLEC algorithm is used to couple pressure and velocity in the calculation process, with a time step of 0.5° per propeller rotation.

[0043] Figure 2 The density distribution provided in the embodiments of the present invention. Figure 3 This invention provides a comparison of simulation results for hydrodynamic noise of an underwater vehicle with a propeller using two methods. One method yields a structure obtained by implementing the method of this invention, while the other method yields a result obtained without implementing the method of this invention. Figure 3 It can be seen that after implementing the method mentioned in this invention, the effect of suppressing the "upward tilt" in the high-frequency band is obvious, which is more in line with the actual physical conditions, proving the effectiveness of the hydrodynamic noise calculation method for suppressing the "upward tilt" phenomenon in the high-frequency band in this embodiment.

[0044] Based on the method described in the above embodiments, this embodiment will further describe it from the perspective of a high-frequency noise calculation system for underwater vehicles based on fluid compressibility. This high-frequency noise calculation system for underwater vehicles based on fluid compressibility can be implemented as an independent entity or integrated into an electronic device. The electronic device can be a terminal, server, or other device. The terminal can include a tablet computer, a laptop computer, a personal computer (PC), a microprocessor box, or other devices.

[0045] Please see Figure 4 , Figure 4 This invention specifically describes a high-frequency noise calculation system for underwater vehicles based on fluid compressibility, applicable to electronic devices. The system may include: The compressible water flow density distribution calculation module is used to obtain the local static pressure of the flow field and calculate the density distribution of the compressible water flow based on the local static pressure of the flow field and the compressibility characteristics of the water body. The water flow control equation construction module is used to construct water flow control equations that consider fluid compressibility based on the density distribution of the compressible water flow, and to solve the velocity distribution, pressure distribution and density fluctuation distribution of the flow field through numerical iteration. The FW-H equation construction module constructs the FW-H equation based on the density distribution of the compressible water flow, the velocity distribution of the flow field, the pressure distribution of the flow field, and the density fluctuation distribution of the flow field. The underwater vehicle high-frequency noise solution module is used to embed the water flow control equation considering fluid compressibility and the FW-H equation into the computational fluid dynamics solver for solving, and obtain the calculation results of the underwater vehicle high-frequency noise.

[0046] In specific implementation, the above modules and / or units can be implemented as independent entities, or they can be arbitrarily combined and implemented as the same or several entities. For the specific implementation of the above modules and / or units, please refer to the previous method embodiments. For the specific beneficial effects that can be achieved, please also refer to the beneficial effects in the previous method embodiments, which will not be repeated here.

[0047] In addition, this embodiment of the invention also provides an electronic device, which may be a computer, tablet computer, or other similar device. This electronic device can implement the steps in any embodiment of the underwater vehicle high-frequency noise calculation method based on fluid compressibility provided in this embodiment of the invention. Therefore, it can achieve the beneficial effects achievable by any of the underwater vehicle high-frequency noise calculation methods based on fluid compressibility provided in this embodiment of the invention, as detailed in the preceding embodiments, and will not be repeated here.

[0048] Figure 5 A specific structural block diagram of an electronic device provided in an embodiment of the present invention is shown. This electronic device can be used to implement the high-frequency noise calculation method for underwater vehicles based on fluid compressibility provided in the above embodiments. The electronic device 500 can be a terminal, server, or other device. The terminal can include a tablet computer, laptop computer, personal computer (PC), microprocessor box, or other devices.

[0049] The memory 520 can be used to store software programs and modules, such as the program instructions / modules corresponding to those in the above embodiments. The processor 580 executes various functional applications and data processing by running the software programs and modules stored in the memory 520. The memory 520 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 520 may further include memory remotely located relative to the processor 580, and these remote memories can be connected to the electronic device 500 via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0050] The input unit 530 can be used to receive input numeric or character information, and to generate a keyboard and mouse related to user settings and function control. Display unit 540 can be used to display information input by the user or information provided to the user, as well as various graphical user interfaces, which can be composed of graphics, text, icons, video, and any combination thereof. Display unit 540 may include display panel 541, which may optionally be configured in the form of LCD (Liquid Crystal Display), OLED (Organic Light-Emitting Diode), or other similar forms.

[0051] Electronic device 500, through transmission module 570 (e.g., Wi-Fi module), can help users receive requests, send information, etc., providing users with wireless broadband internet access. Although transmission module 570 is shown in the figure, it is understood that it is not an essential component of electronic device 500 and can be omitted as needed without changing the essence of the invention.

[0052] The processor 580 is the control center of the electronic device 500. It connects to various parts of the phone via various interfaces and lines, and performs various functions and processes data of the electronic device 500 by running or executing software programs and / or modules stored in the memory 520, and by calling data stored in the memory 520, thereby providing overall monitoring of the electronic device. Optionally, the processor 580 may include one or more processing cores; in some embodiments, the processor 580 may integrate an application processor and a modem processor, wherein the application processor mainly handles the operating system, user interface, and applications, and the modem processor mainly handles wireless communication. It is understood that the modem processor may also not be integrated into the processor 580.

[0053] Electronic device 500 also includes a power supply 590 (such as a battery) that supplies power to various components. In some embodiments, the power supply may be logically connected to processor 580 through a power management system, thereby enabling functions such as charging, discharging, and power consumption management through the power management system. The power supply 590 may also include one or more DC or AC power supplies, recharging systems, power fault detection circuits, power converters or inverters, power status indicators, and other arbitrary components.

[0054] Although not shown, the electronic device 500 also includes cameras (such as front-facing cameras and rear-facing cameras), Bluetooth modules, etc., which will not be described in detail here. Specifically, in this embodiment, the display unit of the electronic device is a touch screen display, and the mobile terminal also includes a memory and one or more programs, wherein one or more programs are stored in the memory and configured to be executed by one or more processors. One or more programs contain instructions for performing the following operations: Obtain the local static pressure of the flow field, and calculate the density distribution of the compressible water flow based on the local static pressure of the flow field and the compressibility characteristics of the water body; Based on the density distribution of the compressible water flow, a water flow control equation considering fluid compressibility is constructed, and the velocity distribution, pressure distribution, and density fluctuation distribution of the flow field are solved by numerical iteration. Based on the density distribution of the compressible water flow, the velocity distribution of the flow field, the pressure distribution of the flow field, and the density fluctuation distribution of the flow field, the FW-H equation is constructed. The flow control equations considering fluid compressibility and the FW-H equations are incorporated into a computational fluid dynamics solver for solving, resulting in calculations of high-frequency noise from underwater vehicles.

[0055] In practice, the above modules can be implemented as independent entities or combined in any way to be implemented as the same or several entities. For the specific implementation of the above modules, please refer to the previous method implementation examples, which will not be repeated here.

[0056] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by instructions, or by instructions controlling related hardware. These instructions can be stored in a computer-readable storage medium and loaded and executed by a processor. Therefore, embodiments of the present invention provide a storage medium storing multiple instructions that can be loaded by a processor to execute the steps of any embodiment of the underwater vehicle high-frequency noise calculation method based on fluid compressibility provided by the present invention.

[0057] The computer-readable storage medium may include: read-only memory (ROM), random access memory (RAM), disk or optical disk, etc.

[0058] Since the instructions stored in the storage medium can execute the steps in any embodiment of the underwater vehicle high-frequency noise calculation method based on fluid compressibility provided in the embodiments of the present invention, the beneficial effects that any underwater vehicle high-frequency noise calculation method based on fluid compressibility provided in the embodiments of the present invention can achieve can be realized, as detailed in the previous embodiments, and will not be repeated here.

[0059] The above provides a detailed description of a high-frequency noise calculation method, system, storage medium, and electronic device for underwater vehicles based on fluid compressibility, as provided in the embodiments of the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for calculating high-frequency noise of underwater vehicles based on fluid compressibility, characterized in that, The method includes: Obtain the local static pressure of the flow field, and calculate the density distribution of the compressible water flow based on the local static pressure of the flow field and the compressibility characteristics of the water body; Based on the density distribution of the compressible water flow, a water flow control equation considering fluid compressibility is constructed, and the velocity distribution, pressure distribution, and density fluctuation distribution of the flow field are solved by numerical iteration. Based on the density distribution of the compressible water flow, the velocity distribution of the flow field, the pressure distribution of the flow field, and the density fluctuation distribution of the flow field, the FW-H equation is constructed. The flow control equations considering fluid compressibility and the FW-H equations are incorporated into a computational fluid dynamics solver for solving, resulting in calculations of high-frequency noise from underwater vehicles.

2. The method for calculating high-frequency noise of underwater vehicles based on fluid compressibility according to claim 1, characterized in that, The density distribution of compressible water flow can be calculated using the following formula: in, For compressible fluid density distribution, This refers to the density of water under saturated conditions. For static pressure in the flow field, The reference pressure is the standard atmosphere. and It is a constant.

3. The method for calculating high-frequency noise of underwater vehicles based on fluid compressibility according to claim 1, characterized in that, The water flow control equation considering fluid compressibility is as follows: in, For time, It is a velocity vector. For Hamiltonian operators, For viscous stress tensor, It is a volume force vector. It is the hydrostatic pressure of the fluid.

4. The method for calculating high-frequency noise of underwater vehicles based on fluid compressibility according to claim 3, characterized in that, The formula for calculating the volume force vector is: in, It is the acceleration due to gravity. It is the unit vector in the z-direction.

5. The method for calculating high-frequency noise of underwater vehicles based on fluid compressibility according to claim 1, characterized in that, The FW-H equations are solved in integral form to obtain the radiated sound pressure. A closed integral surface is chosen, formed by the surface of the underwater vehicle and the virtual surface of the far-field flow field. The FW-H equations are: in, As observation point At any moment The radiated sound pressure pressure pulsation at the location; The source point position vector on the integral surface; The distance from the observation point to the source point of the integral surface. Let be the unit direction vector from the source point to the observation point, and let its _____ be the _____. Each component is denoted as ; Let be the instantaneous density of the fluid on the integral surface; The reference density is for a stationary medium. Let be the instantaneous pressure of the fluid on the integral surface; The reference pressure for the static medium; Let be the fluid velocity vector, and its ______ Each component is denoted as ; Let be the velocity vector of the integral surface, and its ... Each component is denoted as ; Let be the outward normal unit vector of the integral surface, and let its be... Each component is denoted as ; This represents the component of the fluid velocity in the direction normal to the integral surface; This represents the component of the velocity on the integral surface in the normal direction of the integral surface; The speed of sound in a stationary medium; The Mach number vector of the integral surface motion is defined as follows: , its first Each component is ; For the Mach number of the integral surface motion in the radial direction Projection on; For the generalized stress tensor form on the penetration integral surface; For Kronecker delta notation, when The value is 1 if the condition is met, otherwise it is 0. It is the viscous stress tensor; The delay time; symbol Indicates the integrand in the lag time Values ​​are taken at the specified location; symbol Indicates the distance of radiation The partial derivative operation.

6. The method for calculating high-frequency noise of underwater vehicles based on fluid compressibility according to claim 1, characterized in that, The flow control equations considering fluid compressibility and the FW-H equations are incorporated into a computational fluid dynamics solver for solving, yielding calculation results for high-frequency noise of the underwater vehicle, including: The flow control equations considering fluid compressibility and the FW-H equations were written into a C language file, compiled using Visual Studio, and solved in the computational fluid dynamics solver to obtain the calculation results of high-frequency noise of the underwater vehicle.

7. The method for calculating high-frequency noise of underwater vehicles based on fluid compressibility according to claim 1, characterized in that, The method further includes: The SIMPLEC algorithm is used to couple pressure and velocity, with a time step of 0.5° per propeller rotation.

8. A high-frequency noise calculation system for underwater vehicles based on fluid compressibility, characterized in that, include: The compressible water flow density distribution calculation module is used to obtain the local static pressure of the flow field and calculate the density distribution of the compressible water flow based on the local static pressure of the flow field and the compressibility characteristics of the water body. The water flow control equation construction module is used to construct water flow control equations that consider fluid compressibility based on the density distribution of the compressible water flow, and to solve the velocity distribution, pressure distribution, and density fluctuation distribution of the flow field through numerical iteration. The FW-H equation construction module constructs the FW-H equation based on the density distribution of the compressible water flow, the velocity distribution of the flow field, the pressure distribution of the flow field, and the density fluctuation distribution of the flow field. The underwater vehicle high-frequency noise solution module is used to embed the water flow control equation considering fluid compressibility and the FW-H equation into the computational fluid dynamics solver for solving, and obtain the calculation results of the underwater vehicle high-frequency noise.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a plurality of instructions adapted to be loaded by a processor to execute the high-frequency noise calculation method for underwater vehicles based on fluid compressibility as described in any one of claims 1 to 7.

10. An electronic device, characterized in that, It includes a processor and a memory, the processor being electrically connected to the memory, the memory being used to store instructions and data, and the processor being used to execute the steps in the underwater vehicle high-frequency noise calculation method based on fluid compressibility as described in any one of claims 1 to 7.

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