System and method for establishing noise model of ship nuclear power secondary circuit flowmeter

Abstract

The invention provides a ship nuclear power secondary circuit flowmeter noise model building system and method, and the system comprises a grid division module which is used for carrying out the modeling of a ship nuclear power secondary circuit flowmeter and an acoustic propagation domain, and carrying out the grid division of a fluid domain, a solid domain and an acoustic propagation domain of the built model; the noise calculation module is used for performing flow meter noise calculation based on the divided fluid domain, solid domain and sound propagation domain to obtain a flow meter noise sound pressure level curve; the noise model building module is used for building a flowmeter noise model based on the flowmeter noise sound pressure level curve; and the dynamic monitoring module is used for dynamically monitoring and optimizing the noise of the secondary circuit of the nuclear power device in real time based on the flow meter noise model. According to the invention, a more stable, hidden and efficient nuclear power system can be realized, and powerful technical support is provided for stable operation of a nuclear power device.

Description

Technical Field

[0001] The present invention belongs to the technical field of flow-induced vibration noise analysis, and particularly relates to a system and method for establishing a noise model of a flowmeter in the secondary loop of a ship nuclear power plant. Background Art

[0002] In the design and construction stages of the secondary loop of a ship nuclear power plant, due to numerous pipelines and equipment in the system, flow-induced vibration phenomena often occur, leading to strong vibration and noise problems, which have an adverse impact on the stealth of certain specific ship nuclear powers. Therefore, to ensure the safety and reliability of the nuclear power plant, it is necessary to deeply explore the vibration and noise conditions occurring in the system. However, in traditional flowmeter simulation calculations, whenever the working conditions change, it is necessary to recalculate the noise level, which not only requires extremely high computing power but also takes a long time. Using numerical simulation methods to calculate and analyze the noise of the flowmeter in the secondary loop of a ship nuclear power plant can reduce noise generation during the design stage, quickly adapt to changes in working conditions, eliminate the need for complex calculations, reduce the demand for computing power, and provide guiding significance for design, operation, and maintenance.

[0003] Most of the current related technologies for studying flow-induced noise focus on air and water, lacking those for the secondary loop system of nuclear power. Compared with other fluid media, the secondary loop has characteristics such as high temperature, high pressure, and humidity, which can cause flow-induced vibration phenomena in the secondary loop system. Moreover, in a high-temperature and high-pressure steam environment, the force of the fluid on the structure and the influence of the structure on the fluid are both significantly enhanced. Therefore, fluid-structure interaction analysis is crucial for accurately simulating and predicting the noise and vibration characteristics in the secondary loop system. In summary, developing a method for establishing a noise model based on the flowmeter in the secondary loop of a ship nuclear power plant is of great significance for improving the operating stability of ship nuclear power and reducing the cost of simulation calculations. Summary of the Invention

[0004] To solve the problems existing in the prior art, the present invention provides a system and method for establishing a noise model of a flowmeter in the secondary loop of a ship nuclear power plant, which can accurately calculate the noise generated by the flowmeter in the secondary loop due to flow-induced vibration, reduce computing power consumption, and improve calculation efficiency.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A system for establishing a noise model of a flowmeter in the secondary loop of a ship nuclear power plant, the system comprising:

[0007] A mesh generation module, configured to model the flowmeter in the secondary loop of a ship nuclear power plant and the acoustic propagation domain, and perform mesh generation for the fluid domain, solid domain, and acoustic propagation domain of the established model;

[0008] A noise calculation module, which is used to calculate the flowmeter noise based on the divided fluid domain, solid domain and sound propagation domain, and obtain the flowmeter noise sound pressure level curve;

[0009] A noise model construction module, which is used to establish a flowmeter noise model based on the flowmeter noise sound pressure level curve;

[0010] A dynamic monitoring module, which is used to complete the dynamic monitoring and real-time optimization of the secondary loop noise of the nuclear power plant based on the flowmeter noise model.

[0011] Preferably, the noise calculation module includes:

[0012] A fluid domain calculation unit, which is used to perform fluid calculation on the fluid domain by using the computational fluid dynamics method, and obtain the velocity and pressure distribution data of the fluid in the flowmeter;

[0013] A fluid-structure interaction unit, which is used to establish a fluid-structure interaction interface and perform one-way fluid-structure interaction analysis based on the data exchange between the fluid domain and the solid domain, and obtain the velocity and pressure data after fluid-structure interaction;

[0014] An acoustic calculation model construction unit, which is used to construct an acoustic calculation model of the secondary loop flowmeter based on preset acoustic parameters, material properties and boundary conditions;

[0015] A noise sound pressure level acquisition unit, which is used to obtain the noise sound pressure level of the flowmeter based on the velocity and pressure distribution data of the fluid in the flowmeter and the velocity and pressure data after fluid-structure interaction;

[0016] A curve acquisition unit, which is used to obtain the flowmeter noise sound pressure level curve based on the flowmeter noise sound pressure level under different boundary conditions.

[0017] Preferably, in the noise sound pressure level acquisition unit, the velocity and pressure distribution data of the fluid in the flowmeter and the velocity and pressure data after fluid-structure interaction are subjected to frequency domain conversion, and the converted data are imported into the acoustic propagation domain by interpolation to obtain the noise sound pressure level of the flowmeter.

[0018] Preferably, the noise model construction module includes:

[0019] A regression analysis unit, which is used to fit the flowmeter noise sound pressure level curve to obtain the relationship between the noise sound pressure level and each boundary condition;

[0020] A flowmeter noise model unit, which is used to establish the flowmeter noise model based on the relationship between the noise sound pressure level and each boundary condition.

[0021] The present invention also provides a method for establishing a flowmeter noise model for the secondary loop of a ship nuclear power plant. By applying the system, the method includes:

[0022] Model the flowmeter of the secondary loop of a ship's nuclear power plant and the acoustic propagation domain, and perform mesh generation for the fluid domain, solid domain, and acoustic propagation domain of the established model;

[0023] Based on the divided fluid domain, solid domain, and acoustic propagation domain, calculate the flowmeter noise to obtain the flowmeter noise sound pressure level curve;

[0024] Based on the flowmeter noise sound pressure level curve, establish a flowmeter noise model;

[0025] Based on the flowmeter noise model, complete the dynamic monitoring and real-time optimization of the secondary loop noise of the nuclear power plant.

[0026] Preferably, the method for obtaining the flowmeter noise sound pressure level curve includes:

[0027] Adopt the computational fluid dynamics method to perform fluid calculation on the fluid domain to obtain the velocity and pressure distribution data of the fluid in the flowmeter;

[0028] Based on the data exchange between the fluid domain and the solid domain, establish a fluid-structure interaction interface and perform one-way fluid-structure interaction analysis to obtain the velocity and pressure data after fluid-structure interaction;

[0029] Based on the preset acoustic parameters, material properties, and boundary conditions, construct an acoustic calculation model for the secondary loop flowmeter;

[0030] Based on the velocity and pressure distribution data of the fluid in the flowmeter and the velocity and pressure data after fluid-structure interaction, obtain the flowmeter noise sound pressure level;

[0031] Based on the flowmeter noise sound pressure levels under different boundary conditions, obtain the flowmeter noise sound pressure level curve.

[0032] Preferably, the method for obtaining the flowmeter noise sound pressure level includes: performing frequency domain conversion on the velocity and pressure distribution data of the fluid in the flowmeter and the velocity and pressure data after fluid-structure interaction, and importing the converted data into the acoustic propagation domain by interpolation to obtain the flowmeter noise sound pressure level.

[0033] Preferably, the method for constructing the flowmeter noise model includes:

[0034] Fit the flowmeter noise sound pressure level curve to obtain the relationship between the noise sound pressure level and each boundary condition;

[0035] Based on the relationship between the noise sound pressure level and each boundary condition, establish the flowmeter noise model.

[0036] Compared with the prior art, the beneficial effects of the present invention are as follows: Through the accurate noise model establishment system and method for the secondary loop flowmeter of the present invention, the rapid calculation of the noise of the secondary loop flowmeter of the ship nuclear power plant is realized. Compared with the traditional method, the present invention can analyze and accurately calculate the fluid-induced vibration noise of the secondary loop flowmeter more quickly, thus providing a more scientific basis for the design and safe operation of the secondary loop. This method not only improves the speed of noise calculation, but also reduces the necessity of recalculating the noise level under different working conditions, improving the operation efficiency and safety of the system. In addition, the method of the present invention also has high adaptability and flexibility, and can establish a noise model for secondary loop equipment with the same high temperature, high pressure and wet steam medium. It realizes the dynamic monitoring and real-time optimization of the secondary loop noise of the nuclear power plant. This innovative methodology provides a new technical means for the design, manufacture and maintenance of ship nuclear power plants, helps to promote the development of ship nuclear power technology, and improves the overall performance and competitiveness of ships. Through the application of the present invention, it can be expected that in future ship designs, a more quiet, environmentally friendly and efficient nuclear power system will be able to be realized, contributing to the sustainable development of the nuclear-powered ship industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0038] Figure 1 Schematic structural diagram of the system for establishing the noise model of the secondary loop flowmeter of the ship nuclear power in the embodiment of the present invention;

[0039] Figure 2 Specific execution diagram of the method for modeling the noise model of the flowmeter in the embodiment of the present invention;

[0040] Figure 3 Schematic diagram of the method for establishing the noise model of the secondary loop flowmeter of the ship nuclear power in the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0042] To make the above objects, features, and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] Embodiment 1

[0044] As Figure 1 、 Figure 2 shown, a system for establishing a noise model of a flowmeter in the secondary loop of a ship nuclear power plant includes: a grid division module, a noise calculation module, a noise model construction module, and a dynamic monitoring module;

[0045] The grid division module is used to model the flowmeter in the secondary loop of the ship nuclear power plant and the acoustic propagation domain. The model should reflect the geometric characteristics of the flowmeter in detail. Mesh division is performed on the established model for the fluid domain, solid domain, and acoustic propagation domain; the mesh division should ensure sufficient fineness to capture flow details and acoustic characteristics, while avoiding excessive refinement to increase the computational amount.

[0046] The noise calculation module is used to calculate the flowmeter noise based on the divided fluid domain, solid domain, and acoustic propagation domain to obtain the noise sound pressure level curve of the flowmeter; a further embodiment is that the noise calculation module includes:

[0047] The fluid domain calculation unit is used to adopt the computational fluid dynamics (CFD) method. First, a steady-state calculation is performed using the k-e model, and after the system is stable, a transient calculation is performed using the LES large eddy model to obtain the transient velocity and pressure distribution data of the fluid in the flowmeter; in this embodiment, the turbulent characteristics of the fluid should be considered, and a suitable turbulent model should be selected for calculation. For the rotating flow situation, the k-w model should be selected, and for the rest of the situations, the k-e model should be selected. In this model, the k-e model should be selected. For the k-e model, the turbulent kinetic energy k and its dissipation rate are obtained from the following transport equations:

[0048]

[0049] In the formula, ρ represents the fluid density, ε represents the turbulent dissipation rate, G k represents the turbulent kinetic energy generated due to the mean velocity gradient, G b represents the turbulent kinetic energy generated by buoyancy, Y M represents the dissipation of the turbulent kinetic energy generated due to the strain rate, S k represents the source term of the turbulent kinetic energy, S ε represents the source term of the turbulent dissipation rate.

[0050] The default constants are as follows:

[0051] C 1ε = 1.44, C 2ε = 1.92, C μ = 0.09, σk = 1.0, σ ε = 1.3

[0052] These default values are determined from experiments on basic turbulence, including commonly encountered shear flows such as boundary layers, mixing layers, and jets, as well as decaying isotropic grid turbulence. They have been found to be quite effective for various wall boundaries and free shear flows.

[0053] LES differentiates the eddy scale sizes through a filtering function and considers each variable as consisting of two parts: the mean variable with relatively large scales and the variable φ′ characterizing the small-scale conditions. For any variable at a certain moment, the variable φ to be sought is:

[0054]

[0055] In the formula, the mean variable can be expressed in the following form:

[0056]

[0057] In the formula, D represents the fluid control region, G is the filtering function mentioned above used to differentiate the eddy scales, and G can have various expressions depending on the type of problem and the simulation model. For the finite volume method, the discretization process of the control equation actually uses the filtering function for processing, and the specific operation process of the filtering function can also be understood as averaging the physical quantity over the control volume:

[0058]

[0059] In the formula, x′ represents each position when integrating the function φ within the domain D, V represents the size of the control volume, and for an incompressible fluid, it can be obtained that:

[0060]

[0061] The above formula is the most basic control equation set in the LES simulation method, where x i and x j represent the physical space; t is the flow time of the flow field, s; represents the static pressure of the flow field, Pa; τ ij is the sub-grid stress term, which can be expressed as:

[0062]

[0063] τ ijIt can be used to characterize the specific influence of small-scale eddies on the solved motion equations. There are various forms of sub-grid models. In the embodiments of the present invention, since subsequent successive calculations related to flow noise need to be carried out, the Smagorinsky-Lilly model is selected. In the Smagorinsky-Lilly model, τ ij term can be further expressed as:

[0064]

[0065] In the formula, τ kk is the isotropic correction term considered in the sub-grid stress term; δ ij represents the Kronecker function; μ t is the viscosity term considering the sub-grid model, and

[0066]

[0067] is the Reynolds stress strain rate tensor, which can be specifically expressed as: s Δ) 2 is usually determined by the grid size and the grid mixing length, and C s is a constant.

[0068] In this way, the construction of the sub-grid model enables the control equation to be closed, and the above theory is the derivation process of the classical LES model.

[0069] The fluid-structure interaction unit is used to establish a fluid-structure interaction interface and perform one-way fluid-structure interaction analysis based on the data exchange between the fluid domain and the solid domain, so as to obtain the velocity and pressure data after fluid-structure interaction; specifically, since the secondary loop is steam with high temperature, high pressure and humidity, it will cause fluid-induced vibration in the secondary loop system. In the high-temperature and high-pressure steam environment, the force of the fluid on the structure and the influence of the structure on the fluid are both significantly enhanced. Therefore, fluid-structure interaction analysis is crucial for accurately simulating and predicting the noise characteristics in the secondary loop system, which is a fundamental and necessary step for subsequent noise analysis and model establishment.

[0070] Specifically, in this embodiment, a fluid-structure interaction interface is set. In ANSYS Mechanical, the fluid-structure interaction interface is defined by creating a System Coupling Region, and one-way fluid-structure interaction analysis is carried out using Workbench software to transfer the fluid pulsating velocity and pressure to the wall surface. In this step, it is necessary to ensure the accurate data exchange between the fluid domain and the solid domain to obtain the velocity and pressure data after fluid-structure interaction.

[0071] An acoustic calculation model construction unit, which is used to construct the acoustic calculation boundary conditions of the secondary loop flowmeter based on preset acoustic parameters, material properties, and boundary conditions; in this embodiment, an acoustic calculation model of the secondary loop flowmeter is established based on the computational acoustics software Actran. As Figure 2 shown, set acoustic parameters, such as the density and sound speed of the propagation medium and noise source, and the material properties of the pipeline, to simulate the propagation of sound waves in the flowmeter and the surrounding working medium.

[0072] A noise sound pressure level acquisition unit, which is used to obtain the noise sound pressure level of the flowmeter based on the velocity and pressure distribution data of the fluid in the flowmeter and the velocity and pressure data after fluid-structure interaction; a further implementation is that in the noise sound pressure level acquisition unit, the velocity and pressure distribution data of the fluid in the flowmeter and the velocity and pressure data after fluid-structure interaction are subjected to frequency domain conversion, and the converted data is imported into the acoustic propagation domain by interpolation to obtain the noise sound pressure level of the flowmeter, where the flow noise is the noise generated by the fluid without adding wall conditions; under the condition of adding wall conditions, the force of the fluid on the pipe wall will cause the pipe wall to vibrate and displace, resulting in vibration noise, and the total noise is the sum of the flow noise and the vibration noise.

[0073] A curve acquisition unit, which is used to obtain the noise sound pressure level curve of the flowmeter based on the noise sound pressure levels of the flowmeter under different boundary conditions. In this embodiment, different boundary conditions are changed, and the mesh division module and the noise calculation module are repeatedly executed to obtain the noise sound pressure level curves of the flowmeter under different boundary conditions.

[0074] A noise model construction module, which is used to establish a noise model of the flowmeter based on the noise sound pressure level curve of the flowmeter; a further implementation is that the noise model construction module includes:

[0075] A regression analysis unit, which is used to fit the noise sound pressure level curve of the flowmeter to obtain the relationship between the noise sound pressure level and each boundary condition;

[0076] A flowmeter noise model unit, which is used to establish a noise model of the flowmeter based on the relationship between the noise sound pressure level and each boundary condition.

[0077] A dynamic monitoring module, which is used to complete the dynamic monitoring and real-time optimization of the secondary loop noise of the nuclear power plant based on the flowmeter noise model.

[0078] The present invention specifically addresses the problem of frequent noise measurement of flow meters in the secondary loop of nuclear power plants under varying operating conditions. In traditional simulation calculations of flow meters, whenever the operating conditions change, it is necessary to recalculate the noise level, which not only requires extremely high computing power but also takes a long time. By establishing a complete noise model, it can quickly adapt to changes in operating conditions without the need to repeat complex calculations, thus significantly reducing the demand for computing power and improving the measurement efficiency. At the same time, this method is specifically aimed at the high-temperature, high-pressure, and humid steam environment in the secondary loop of nuclear-powered ships, which is different from working media such as water and air. Compared with other working media, this method can accurately simulate and predict the fluid-induced vibration and noise characteristics generated under such special operating conditions, solving the problem of insufficient adaptability to such complex environments in the prior art. Through the application of this method, a more stable, concealed, and efficient nuclear power system can be realized, providing strong technical support for the stable operation of nuclear power plants.

[0079] Embodiment 2

[0080] As Figure 3 shown, the present invention also provides a method for establishing a noise model of a flow meter in the secondary loop of a ship nuclear power plant. The application system and method include:

[0081] S1: Model the flow meter in the secondary loop of the ship nuclear power plant and the acoustic propagation domain, and perform mesh division on the established model for the fluid domain, solid domain, and acoustic propagation domain;

[0082] S2: Calculate the flow meter noise based on the divided fluid domain, solid domain, and acoustic propagation domain to obtain the flow meter noise sound pressure level curve;

[0083] S3: Establish a flow meter noise model based on the flow meter noise sound pressure level curve;

[0084] S4: Based on the flow meter noise model, complete the dynamic monitoring and real-time optimization of the noise in the secondary loop of the nuclear power plant.

[0085] A further implementation method is that the method for obtaining the flow meter noise sound pressure level curve includes:

[0086] Adopt the computational fluid dynamics method to perform fluid calculation on the fluid domain to obtain the velocity and pressure distribution data of the fluid in the flow meter;

[0087] Based on the data exchange between the fluid domain and the solid domain, establish a fluid-structure interaction interface and perform one-way fluid-structure interaction analysis to obtain the velocity and pressure data after fluid-structure interaction;

[0088] Based on the preset acoustic parameters, material properties, and boundary conditions, construct an acoustic calculation model of the secondary loop flow meter;

[0089] Based on the velocity and pressure distribution data of the fluid in the flowmeter and the velocity and pressure data after fluid-structure interaction, obtain the noise sound pressure level of the flowmeter;

[0090] Based on the noise sound pressure levels of the flowmeter under different boundary conditions, obtain the noise sound pressure level curve of the flowmeter.

[0091] A further implementation manner is that the method for obtaining the noise sound pressure level of the flowmeter includes: performing frequency-domain conversion on the velocity and pressure distribution data of the fluid in the flowmeter and the velocity and pressure data after fluid-structure interaction, and importing the converted data into the acoustic propagation domain by interpolation to obtain the noise sound pressure level of the flowmeter.

[0092] A further implementation manner is that the method for constructing the flowmeter noise model includes:

[0093] Fit the noise sound pressure level curve of the flowmeter to obtain the relationship between the noise sound pressure level and each boundary condition;

[0094] Based on the relationship between the noise sound pressure level and each boundary condition, establish a flowmeter noise model.

[0095] Through the above steps, the present application provides a systematic method for establishing a noise model of a flowmeter in the secondary loop of a ship nuclear power plant. This method not only improves the speed of noise calculation, but also reduces the necessity of recalculating the noise level under different working conditions, and improves the operation efficiency and safety of the system.

[0096] First, through precise modeling and mesh generation, this method ensures a detailed description of the flowmeter and its acoustic propagation domain, providing a solid foundation for subsequent fluid dynamics analysis. Then, through fluid computational analysis and fluid-structure interaction analysis, this method can accurately capture the flow characteristics of the fluid in the flowmeter and the interaction between the fluid and the solid structure, which is crucial for understanding the generation mechanism of flow-induced vibration.

[0097] In addition, through the establishment of the acoustic model and data conversion and acoustic analysis, this method can comprehensively evaluate the noise characteristics of the flowmeter under different working conditions. This provides valuable information for ship designers to consider the noise control requirements at the design stage.

[0098] By changing different boundary conditions and repeating the calculation, this method allows designers to explore various possible working conditions, so as to optimize the design to meet specific performance requirements. Then, find the change relationship formula of the noise sound pressure level through noise parameter regression analysis, and finally, establish a noise model according to the obtained formula. This method ensures that the established noise model can meet the accuracy requirements of noise calculation, while reducing the computational amount to be consumed and improving the calculation speed.

[0099] The method of the present invention is applied to the fields of energy, power engineering, and mechanical engineering, especially in the design, optimization, and fault diagnosis of flowmeter systems. This technical field covers the intersection of multiple disciplines such as fluid dynamics, solid mechanics, and acoustics, aiming to reduce the necessity of recalculating the noise level under different working conditions through algorithms and lower the requirement for computing power to quickly detect the noise level.

[0100] The method of the present invention can not only accurately calculate the noise of secondary loop equipment with high-temperature, high-pressure, and humid steam as the working medium. At the same time, the rapid calculation of noise through the model also helps to quickly detect the noise level of ships. This helps to improve the safety of ship nuclear power and enhance the stealth of ships. These advantages make the present invention have important application value in the design and operation of ship nuclear power plants.

[0101] The above-described embodiments are only descriptions of the preferred embodiments of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A noise model establishment system for a nuclear powered secondary circuit flow meter of a ship, characterized in that: The system comprises: The meshing module is used to model the secondary circuit flowmeter of the ship's nuclear power and the acoustic propagation domain, and to mesh the fluid domain, solid domain, and acoustic propagation domain of the established model; A noise calculation module, used to calculate the flow meter noise based on the divided fluid domain, the solid domain and the sound propagation domain, and obtain a flow meter noise sound pressure level curve; A noise model building module, used to build a flow meter noise model based on the flow meter noise sound pressure level curve; The dynamic monitoring module is used to complete the dynamic monitoring and real-time optimization of the secondary circuit noise of the nuclear power plant based on the flow meter noise model.

2. The system according to claim 1, characterized in that The noise calculation module comprises: A fluid domain calculation unit, used to perform fluid calculation on the fluid domain by using a computational fluid dynamics method, and obtain velocity and pressure distribution data of the fluid in the flow meter; A fluid-solid coupling unit, used to establish a fluid-solid coupling interface and perform one-way fluid-solid coupling analysis based on data exchange between the fluid domain and the solid domain, so as to obtain velocity and pressure data after fluid-solid coupling; An acoustic calculation model building unit, used to build an acoustic calculation model of a secondary circuit flow meter based on preset acoustic parameters, material properties and boundary conditions; A noise sound pressure level acquisition unit, used to obtain the noise sound pressure level of the flow meter based on the velocity and pressure distribution data of the fluid in the flow meter and the velocity and pressure data after fluid-solid coupling; The curve acquisition unit is used to obtain the flow meter noise sound pressure level curve based on the flow meter noise sound pressure level under different boundary conditions.

3. The system according to claim 2, characterized in that In the noise sound pressure level acquisition unit, the velocity and pressure distribution data of the fluid in the flow meter and the velocity and pressure data after fluid-solid coupling are converted into frequency domain, and the converted data are imported into the acoustic propagation domain by interpolation to obtain the noise sound pressure level of the flow meter.

4. The system according to claim 1, characterized in that The noise model building module includes: A regression analysis unit, used for fitting the flow meter noise sound pressure level curve to obtain the relationship between the noise sound pressure level and various boundary conditions; The flow meter noise model unit is used to establish the flow meter noise model based on the relationship between the noise sound pressure level and various boundary conditions.

5. A method for establishing a noise model for a secondary flow meter of a nuclear power ship, using the system described in any one of claims 1 to 4, characterized in that: The method comprises: Model the secondary flow meter of the nuclear power ship and the acoustic propagation domain, and divide the fluid domain, solid domain and acoustic propagation domain of the established model into meshes; Calculate the flow meter noise based on the divided fluid domain, solid domain, and sound propagation domain to obtain a flow meter noise sound pressure level curve; Based on the flow meter noise sound pressure level curve, a flow meter noise model is established; Based on the flow meter noise model, dynamic monitoring and real-time optimization of the secondary circuit noise of the nuclear power plant are completed.

6. The method according to claim 5, characterized in that The methods for obtaining the flow meter noise sound pressure level curve include: Using computational fluid dynamics methods, fluid calculation is performed on the fluid domain to obtain velocity and pressure distribution data of the fluid in the flow meter; Based on the data exchange between the fluid domain and the solid domain, a fluid-solid coupling interface is established and a one-way fluid-solid coupling analysis is performed to obtain velocity and pressure data after fluid-solid coupling; Based on the preset acoustic parameters, material properties and boundary conditions, the acoustic calculation model of the secondary circuit flow meter is constructed; Based on the velocity and pressure distribution data of the fluid in the flow meter and the velocity and pressure data after fluid-solid coupling, the noise sound pressure level of the flow meter is obtained; Based on the flow meter noise sound pressure level under different boundary conditions, the flow meter noise sound pressure level curve is obtained.

7. The method according to claim 5, characterized in that The method for obtaining the noise sound pressure level of the flow meter includes: performing frequency domain conversion on the velocity and pressure distribution data of the fluid in the flow meter and the velocity and pressure data after fluid-solid coupling, and importing the converted data into the acoustic propagation domain by interpolation to obtain the noise sound pressure level of the flow meter.

8. The method according to claim 5, characterized in that Methods for building flow meter noise models include: Fitting the flow meter noise sound pressure level curve to obtain the relationship between the noise sound pressure level and various boundary conditions; The flow meter noise model is established based on the relationship between the noise sound pressure level and various boundary conditions.

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