A method and system for evaluating flow-induced vibration noise of underwater vehicles considering fluid-structure coupling

Abstract

The present invention discloses a method and system for evaluating the flow-induced vibration noise of an underwater vehicle considering fluid-solid coupling, wherein the method comprises: establishing a geometric model of an underwater vehicle according to drawings and materials; determining the speed of the underwater vehicle, setting a fluid-solid coupling interface, and using an implicit algorithm to perform two-way data transmission between the flow field and the structural field; establishing an acoustic calculation model of the underwater vehicle, importing the pressure pulsation data into it to set the acoustic and structural material parameters; performing a discrete Fourier transform on the time domain data, mapping the pressure pulsation data onto the sound field grid, determining the calculation frequency band of the vibration noise, and calculating the sound pressure distribution around the underwater vehicle; converting the sound pressure distribution into a sound source level, calculating the total noise level of the entire frequency band and the single frequency point noise limit as evaluation parameters; comparing the evaluation parameters with the required limit to determine whether the current solution is feasible. The method can perform a preliminary evaluation of the flow-induced vibration noise of the underwater vehicle in the design stage, thereby improving the rationality of the underwater vehicle design.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater vehicle vibration and noise assessment, and in particular to an underwater vehicle flow-induced vibration and noise assessment method and system considering fluid-solid coupling. Background Art

[0002] As we all know, mechanical noise, hydrodynamic noise and propeller noise are the main components of the noise of large underwater vehicles, which seriously affect the quiet operation of underwater vehicles. When the speed is low, mechanical noise is the main noise source. As the speed increases, hydrodynamic noise and propeller noise gradually become the main noise sources. The use of numerical simulation methods to predict the flow-induced vibration noise of underwater vehicles can provide guidance for the low-noise design of underwater vehicles in the design stage, make rapid predictions in the operation stage, and provide data support in the maintenance stage. At present, there are some prediction methods for underwater vehicle vibration noise, but there is no complete and reliable evaluation process for the evaluation of hydrodynamic noise.

[0003] At present, the relevant technologies mainly include: Related Technology 1 Simulation and Experimental Research on Flow Noise of Underwater Airfoil Structure (Acoustic Technology, October 2013); Related Technology 2 Vibration and Acoustic Radiation of Submarine Model Excited by Turbulent Fluctuation Pressure (Master's Degree Thesis of Dalian University of Technology); Related Technology 3 Research on Hydrodynamic Noise Prediction of Underwater Vehicle Based on LES (Acoustic Technology, Vol. 36, No. 5, 2017). Among them, Related Technology 1 numerically simulates the flow noise of underwater airfoil based on CFD method and compares the calculation results with the experimental results, but does not consider the fluid-solid coupling effect, nor the influence of flow-induced vibration, so the final result is of low accuracy; Related Technology 2 studies the vibration and acoustic radiation characteristics of underwater vehicles under turbulent fluctuating pressure excitation based on random vibration theory, but does not involve specific fluid-solid coupling analysis, vibration and acoustic radiation characteristics evaluation process, etc., and the implementation process is cumbersome and inefficient; Related Technology 3 numerically predicts the hydrodynamic noise of underwater vehicles based on LES method, but this method does not consider the fluid-solid coupling effect, focuses more on flow noise, and ignores the noise caused by flow-induced vibration of underwater vehicles. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an object of the present invention is to propose a method for evaluating flow-induced vibration noise of an underwater vehicle taking fluid-structure coupling into consideration.

[0006] Another object of the present invention is to provide a method system for evaluating flow-induced vibration noise of underwater vehicles taking fluid-structure coupling into consideration.

[0007] Another object of the present invention is to provide a computer device.

[0008] Another object of the present invention is to provide a non-transitory computer-readable storage medium.

[0009] To achieve the above-mentioned purpose, an embodiment of the present invention proposes a method for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-solid coupling, comprising the following steps: step S1, establishing a geometric model of an underwater vehicle according to preset drawings and materials, placing the geometric model of the underwater vehicle in a fluid domain, and establishing a fluid domain mesh model and a structural finite element model respectively according to the geometric model of the underwater vehicle; step S2, determining the speed of the underwater vehicle, setting a fluid-solid coupling interface, using an implicit algorithm to perform bidirectional data transmission between the flow field and the structural field, and obtaining pressure pulsation data; step S3, establishing an acoustic calculation model of the underwater vehicle based on the computational acoustics software Virtual.Lab, and importing the pressure pulsation data into the acoustic calculation model of the underwater vehicle In the model, a grid model of the sound field around the underwater vehicle is established, and acoustic parameters and structural material parameters are set; step S4, discrete Fourier transform is performed on the preset time domain data, the pressure pulsation data is mapped to the grid model of the sound field around the underwater vehicle, the calculation frequency band of the vibration noise is determined, and the sound pressure distribution around the underwater vehicle is calculated; step S5, the sound pressure distribution is converted into a sound source level, and the total noise level of the whole frequency band and the single frequency point noise limit are calculated based on the calculation frequency band, as evaluation parameters; step S6, the evaluation parameter is compared with the preset demand limit to determine whether it is satisfied. If not, iteratively execute steps S1-S6 to perform noise optimization design on the preset drawing data, and re-evaluate. Otherwise, the preset drawing data is feasible.

[0010] The method for evaluating the flow-induced vibration noise of an underwater vehicle considering fluid-solid coupling in an embodiment of the present invention takes into account the influence of the fluid-solid coupling effect on the structure and flow field information, so that the prediction result when resonance occurs is more reliable, while ensuring the calculation efficiency. It has a guiding role in the protection design of low-frequency vibration noise, and can perform a preliminary evaluation of the flow-induced vibration noise of the underwater vehicle in the design stage, improve the rationality of the underwater vehicle design, and can be applied to the design and control of the flow-induced vibration noise of large underwater vehicles.

[0011] In addition, the method for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-structure coupling according to the above embodiment of the present invention may also have the following additional technical features:

[0012] Furthermore, in one embodiment of the present invention, in said step S1, the distance between the inlet of the fluid domain and the bow of the underwater vehicle geometric model is greater than 6L, the distance between the outlet of the fluid domain and the stern of the underwater vehicle geometric model is greater than 10L, and the distance between the remaining boundaries of the fluid domain and the underwater vehicle geometric model is greater than 3L, wherein L is the total length of the underwater vehicle.

[0013] Furthermore, in one embodiment of the present invention, the step S2 specifically includes: step S201, determining the speed of the underwater vehicle of the underwater vehicle geometric model in the fluid domain; step S202, setting the surface of the underwater vehicle geometric model in the fluid domain and the surface of the underwater vehicle geometric model in the structural field as a fluid-solid coupling interface; step S203, using an implicit algorithm to calculate the pulsating pressure of the fluid in the fluid domain on the structural surface, and then transmitting the pulsating pressure data to the structural field, calculating the displacement of the structural surface in the structural field, and then transmitting the structural surface displacement to the fluid domain, updating the structural surface in the fluid domain, and obtaining the pressure pulsation data.

[0014] Furthermore, in one embodiment of the present invention, the step S3 specifically includes: step S301, establishing the underwater vehicle acoustic calculation model in the computational acoustics software Virtual.Lab according to the structural finite element model; step S302, importing the pressure pulsation data into the underwater vehicle acoustic calculation model to establish a grid model of the sound field around the underwater vehicle; step S303, establishing a plurality of noise monitoring points in the grid model of the sound field around the underwater vehicle according to preset analysis requirements, and setting the acoustic parameters and structural material parameters according to preset media.

[0015] To achieve the above-mentioned purpose, another embodiment of the present invention proposes an underwater vehicle flow-induced vibration noise evaluation system considering fluid-solid coupling, including: a geometric model construction module, used to establish an underwater vehicle geometric model according to preset drawing materials, the underwater vehicle geometric model needs to be placed in a fluid domain, and a fluid domain grid model and a structural finite element model are respectively established according to the underwater vehicle geometric model; a two-way data transmission module, used to determine the speed of the underwater vehicle, set the fluid-solid coupling interface, use an implicit algorithm to perform two-way data transmission between the flow field and the structural field, and obtain pressure pulsation data; a parameter setting module, used to establish an underwater vehicle acoustic calculation model based on the computational acoustics software Virtual.Lab, and import the pressure pulsation data into the underwater vehicle acoustic calculation model A grid model of the sound field around the underwater vehicle is established in the model, and acoustic parameters and structural material parameters are set; a frequency band acquisition module is used to perform discrete Fourier transform on preset time domain data, map the pressure pulsation data to the grid model of the sound field around the underwater vehicle, determine the calculation frequency band of the vibration noise, and calculate the sound pressure distribution around the underwater vehicle; an evaluation parameter acquisition module is used to convert the sound pressure distribution into a sound source level, and calculate the total noise level of the full frequency band and the single frequency point noise limit based on the calculation frequency band as evaluation parameters; an evaluation module is used to compare the evaluation parameters with the preset demand limit to determine whether they are satisfied. If not, iteratively execute steps S1-S6 to perform noise optimization design on the preset drawing materials and re-evaluate. Otherwise, the preset drawing materials are feasible.

[0016] The underwater vehicle flow-induced vibration and noise evaluation system considering fluid-solid coupling in the embodiment of the present invention takes into account the influence of the fluid-solid coupling effect on the structure and flow field information, so that the prediction result when resonance occurs is more reliable, while ensuring the calculation efficiency. It has a guiding role in the protection design of low-frequency vibration noise, and can perform a preliminary evaluation of the flow-induced vibration and noise of the underwater vehicle in the design stage, improve the rationality of the underwater vehicle design, and can be applied to the design and control of the flow-induced vibration and noise of large underwater vehicles.

[0017] In addition, the underwater vehicle flow-induced vibration noise assessment system considering fluid-structure coupling according to the above embodiment of the present invention may also have the following additional technical features:

[0018] Furthermore, in one embodiment of the present invention, the distance between the inlet of the fluid domain in the geometric model construction module and the bow of the underwater vehicle geometric model is greater than 6L, the distance between the outlet of the fluid domain and the stern of the underwater vehicle geometric model is greater than 10L, and the distance between the remaining boundaries of the fluid domain and the underwater vehicle geometric model is greater than 3L, wherein L is the total length of the underwater vehicle.

[0019] Furthermore, in one embodiment of the present invention, the bidirectional data transmission module is specifically used to: determine a speed unit for determining the speed of the underwater vehicle of the underwater vehicle geometric model in the fluid domain; set an interface unit for setting the surface of the underwater vehicle geometric model in the fluid domain and the surface of the underwater vehicle geometric model in the structural field as a fluid-solid coupling interface; a bidirectional data transmission unit for calculating the pulsating pressure of the fluid in the fluid domain on the structural surface using an implicit algorithm, and then transmitting the pulsating pressure data to the structural field, calculating the displacement of the structural surface in the structural field, and then transmitting the structural surface displacement to the fluid domain, updating the structural surface in the fluid domain, and obtaining the pressure pulsation data.

[0020] Furthermore, in one embodiment of the present invention, the parameter setting module is specifically used to: construct an acoustic calculation module unit for establishing the underwater vehicle acoustic calculation model in the computational acoustics software Virtual.Lab according to the structural finite element model; construct a sound field grid model unit for importing the pressure pulsation data into the underwater vehicle acoustic calculation model to establish a sound field grid model around the underwater vehicle; and set a parameter unit for establishing a plurality of noise monitoring points in the sound field grid model around the underwater vehicle according to preset analysis requirements, and setting the acoustic parameters and structural material parameters according to preset media.

[0021] In another aspect, an embodiment of the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the method for evaluating flow-induced vibration noise of an underwater vehicle taking into account fluid-solid coupling as described in the above embodiment is implemented.

[0022] In another aspect, an embodiment of the present invention provides a non-temporary computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for evaluating flow-induced vibration noise of an underwater vehicle taking into account fluid-solid coupling as described in the above embodiment.

[0023] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0025] Figure 1 A flowchart of a method for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-structure coupling according to an embodiment of the present invention;

[0026] Figure 2 A specific execution diagram of flow-induced vibration noise assessment of an underwater vehicle according to an embodiment of the present invention;

[0027] Figure 3 A schematic diagram of an underwater vehicle model according to an embodiment of the present invention;

[0028] Figure 4 is a numerical prediction result of flow-induced noise of an underwater vehicle according to an embodiment of the present invention;

[0029] Figure 5 Schematic diagram of the flow-induced noise evaluation result of an underwater vehicle according to an embodiment of the present invention;

[0030] Figure 6 The figure is a schematic diagram of the structure of a flow-induced vibration noise evaluation system for an underwater vehicle considering fluid-structure coupling according to an embodiment of the present invention. DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0032] The following describes a method and system for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-solid coupling according to an embodiment of the present invention with reference to the accompanying drawings. First, a method and system for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-solid coupling according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0033] Figure 1 The present invention is a flowchart of a method for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-structure coupling according to an embodiment of the present invention.

[0034] like Figure 1 As shown, the method for evaluating flow-induced vibration noise of underwater vehicles considering fluid-structure coupling includes the following steps:

[0035] In step S1, a geometric model of an underwater vehicle is established according to preset drawing data, the geometric model of the underwater vehicle is placed in a fluid domain, and a fluid domain mesh model and a structural finite element model are established respectively according to the geometric model of the underwater vehicle.

[0036] It should be noted that in step S1, the distance between the inlet of the fluid domain and the bow of the underwater vehicle geometric model is greater than 6L, the distance between the outlet of the fluid domain and the stern of the underwater vehicle geometric model is greater than 10L, and the distance between the remaining boundaries of the fluid domain and the underwater vehicle geometric model is greater than 3L, where L is the total length of the underwater vehicle.

[0037] In step S2, the speed of the underwater vehicle is determined, a fluid-solid coupling interface is set, and an implicit algorithm is used to perform bidirectional data transmission between the flow field and the structural field to obtain pressure pulsation data.

[0038] Furthermore, in one embodiment of the present invention, step S2 specifically includes:

[0039] Step S201, determining the underwater vehicle speed of the underwater vehicle geometric model in the fluid domain;

[0040] Step S202, setting the surface of the underwater vehicle geometric model in the fluid domain and the surface of the underwater vehicle geometric model in the structure field as a fluid-solid coupling interface;

[0041] Step S203, using an implicit algorithm to calculate the pulsating pressure of the fluid in the fluid domain on the structural surface, then transmitting the pulsating pressure data to the structural field, calculating the displacement of the structural surface in the structural field, and then transmitting the structural surface displacement to the fluid domain, updating the structural surface in the fluid domain, and obtaining pressure pulsation data.

[0042] Specifically, Figure 2 As shown, the underwater vehicle speed of the underwater vehicle geometric model in the fluid domain is determined, the underwater vehicle surface in the fluid domain and the underwater vehicle surface in the structural field are set as fluid-solid coupling interfaces, and an implicit algorithm is used. In each iteration step, the pulsating pressure of the fluid on the structural surface in the flow field is first calculated, and then the pulsating pressure data is transmitted to the structural field, the displacement of the structural surface is calculated in the structural field, and then the structural surface displacement is transmitted to the flow field, and the structural surface in the flow field is updated, thereby obtaining pressure pulsation data.

[0043] In step S3, an underwater vehicle acoustic calculation model is established based on the computational acoustics software Virtual.Lab, the pressure pulsation data is imported into the underwater vehicle acoustic calculation model to establish a grid model of the sound field around the underwater vehicle, and the acoustic parameters and structural material parameters are set.

[0044] Furthermore, in one embodiment of the present invention, step S3 specifically includes:

[0045] Step S301, establishing an underwater vehicle acoustic calculation model in the computational acoustics software Virtual.Lab according to the structural finite element model;

[0046] Step S302, importing the pressure pulsation data into the underwater vehicle acoustic calculation model to establish a grid model of the sound field around the underwater vehicle;

[0047] Step S303, establishing a plurality of noise monitoring points in the sound field grid model around the underwater vehicle according to preset analysis requirements, and setting acoustic parameters and structural material parameters according to preset media.

[0048] That is to say, an underwater vehicle acoustic calculation model is established in the acoustic software based on the structural finite element model, and the pressure pulsation data is imported into the underwater vehicle acoustic calculation model. The bow and stern directions of the vehicle are taken as the x-axis, the port and starboard directions of the vehicle are taken as the y-axis, and the height direction is taken as the z-axis. Three xyz sections are established through the vehicle as the sound field, that is, the sound field grid model around the underwater vehicle. Then, multiple noise monitoring points are established in the sound field according to the analysis requirements, and the sound pressure at a distance of 1m from the vehicle is obtained through the sound pressure conversion formula. The sound pressure level is used as the sound source level to evaluate the noise level of the underwater vehicle. Then, the acoustic parameters and structural material parameters are set according to the preset medium.

[0049] In step S4, a discrete Fourier transform is performed on the preset time domain data, the pressure pulsation data is mapped to the sound field grid model around the underwater vehicle, the calculation frequency band of the vibration noise is determined, and the sound pressure distribution around the underwater vehicle is calculated.

[0050] Among them, the corresponding upper limits of vibration noise prediction frequency f1 and f2 can be calculated according to the acoustic grid size and time domain in the sound field grid model around the underwater vehicle, and the final calculation frequency band is 10-fHz (f is the smaller value of f1 and f2).

[0051] In step S5, the sound pressure distribution is converted into a sound source level, and the total noise level of the entire frequency band and the single-frequency noise limit are calculated based on the calculation frequency band to serve as evaluation parameters.

[0052] Specifically, the equivalent sound pressure level at 1m on the port side of the underwater vehicle centroid is first taken as the sound source level of the underwater vehicle. Assuming the frequency interval of the sound source level spectrum curve is 1Hz, the noise source level conversion formula is as follows:

[0053]

[0054] Among them, A is the sound pressure level difference between the sound pressure target point and the sound source point, d1 is the distance between the far-field sound pressure point and the centroid of the aircraft, and d2 is the distance between the near-field sound source point and the centroid of the aircraft.

[0055] Then, the total noise level of the entire frequency band is calculated according to the following formula:

[0056]

[0057] Among them, L p is the total sound pressure level of the aircraft noise calculation frequency band, L pi Indicates the sound pressure level at each frequency point.

[0058] Then, the surface pulsating pressure and structural natural vibration frequency of the underwater vehicle are tested or calculated to obtain the main peak frequency of the pulsating pressure and the frequency corresponding to the first three natural modes of the structure, that is, the single-frequency noise limit. Finally, these full-band total noise level and single-frequency noise limit are used as parameters for the evaluation of flow-induced vibration noise of underwater vehicles.

[0059] In step S6, the evaluation parameters are compared with the preset demand limits to determine whether they are met. If not, steps S1-S6 are iteratively executed to perform noise optimization design on the preset drawing materials and re-evaluate. Otherwise, the preset drawing materials are feasible.

[0060] Specifically, the noise assessment includes calculating the total sound source level in the frequency band and the peak noise results at the above-mentioned specific frequency points. Only when the total sound source level and the single-frequency noise meet the design index requirements, the underwater vehicle flow-induced vibration noise assessment is passed. Otherwise, the underwater vehicle design plan will be revised and re-evaluated until the vibration noise assessment is passed.

[0061] The method for evaluating flow-induced vibration noise of an underwater vehicle taking into account fluid-solid coupling proposed by the present invention is further described below through a specific embodiment.

[0062] Combination Figure 2 and 3 The underwater navigation body is set to be 1.2m long, 200mm in diameter and 2mm thick.

[0063] Step 1: Establish the underwater vehicle geometry model in Solidworks software according to the drawings, import the geometry model into Star CCM+ software to establish a flow field that meets the requirements, and use the large eddy simulation method to keep the wall y+ value about 1. Import the geometry model into Abaqus software to establish a structural finite element model, select the calculation frequency band as 1000Hz, and determine the structure grid size to be less than 0.025m according to the principle that the grid size is less than 1 / 6 of the wavelength;

[0064] Step 2: The surface of the underwater vehicle in the fluid domain and the surface of the underwater vehicle in the structural field are set as the fluid-solid coupling interface. The implicit algorithm is used and the time step is set to 5e-4s. At the beginning of each time step in the calculation process, Star CCM+ first transfers the structural surface pressure data to Abaqus. The structural field calculates the structural surface displacement and transfers the displacement data back to Star CCM+. The residual is reduced through repeated iterations, and the next time step is iterated after the calculation converges.

[0065] Step three, based on the computational acoustics software Virtual Lab, an underwater vehicle acoustic calculation model is established, and the pressure pulsation data calculated in step two is imported. The bow and stern direction of the vehicle is taken as the x-axis, the port and starboard direction of the vehicle is taken as the y-axis, and the height direction is taken as the z-axis. Three xyz sections are established through the vehicle as the sound field, and the spatial distribution of the sound pressure around the vehicle is observed. The size of each sound field section is 20m×20m (not less than 10 times the length of the vehicle), and a far-field sound pressure monitoring point is set at 100m on the starboard side of the vehicle. The acoustic parameters and structural material properties are set according to the medium to which the vehicle belongs.

[0066] Step 4: Figure 4 As shown in the figure, the imported turbulent pulsation pressure time domain data is discrete Fourier transformed, and the calculation result of step 2 is mapped to the acoustic grid surface. According to the acoustic grid size and the time step of the time domain calculation, the vibration noise calculation frequency band is determined to be 10Hz-2000Hz, and the sound pressure distribution around the underwater vehicle is calculated.

[0067] Step 5: According to the total sound pressure level calculation formula and the sound source level conversion formula, the total sound source level of the underwater vehicle is calculated to be 128dB, and the spectrum characteristics of the pulsating pressure load on the surface of the underwater vehicle are analyzed, and the main peak of the pulsating pressure is 35Hz. The natural vibration frequency of the underwater vehicle in the water is calculated, and the first three natural frequencies are calculated. The noise peaks of these four characteristic frequency points are extracted. The design indicators stipulate that the total noise level of the full frequency band shall not exceed 130dB, and the noise peak of a single frequency point shall not exceed 120dB.

[0068] Step 6: Figure 5 As shown in the figure, the total sound source level in the calculation is 128dB, which is less than the design index of 130dB; the maximum single-frequency noise peak is 119dB, which is less than the design index of 120dB, indicating that the design scheme is reasonable and feasible. Otherwise, the design scheme needs to be modified until the total sound source level and the single-frequency noise peak meet the design indicators.

[0069] In summary, the method for evaluating the flow-induced vibration noise of underwater vehicles considering fluid-solid coupling proposed in an embodiment of the present invention takes into account the influence of the fluid-solid coupling effect on the structure and flow field information, so that the prediction result when resonance occurs is more reliable, while ensuring the calculation efficiency, and has a guiding role in the protection design of low-frequency vibration noise. It can also conduct a preliminary evaluation of the flow-induced vibration noise of underwater vehicles in the design stage, improve the rationality of the design of underwater vehicles, and can be applied to the design and control of flow-induced vibration noise of large underwater vehicles.

[0070] Next, a flow-induced vibration noise evaluation system for an underwater vehicle considering fluid-structure coupling according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0071] Figure 6 It is a schematic structural diagram of a flow-induced vibration noise evaluation system for an underwater vehicle considering fluid-solid coupling according to an embodiment of the present invention.

[0072] like Figure 6 As shown, the system 10 includes: a geometric model building module 100 , a bidirectional data transmission module 200 , a parameter setting module 300 , a frequency band acquisition module 400 , an evaluation parameter acquisition module 500 and an evaluation module 600 .

[0073] Among them, the geometric model construction module 100 is used to establish the underwater vehicle geometric model according to the preset drawing data, place the underwater vehicle geometric model in the fluid domain, and respectively establish the fluid domain grid model and the structural finite element model according to the underwater vehicle geometric model. The two-way data transmission module 200 is used to determine the speed of the underwater vehicle, set the fluid-solid coupling interface, use the implicit algorithm to perform two-way data transmission between the flow field and the structural field, and obtain the pressure pulsation data. The parameter setting module 300 is used to establish the underwater vehicle acoustic calculation model based on the computational acoustics software Virtual.Lab, import the pressure pulsation data into the underwater vehicle acoustic calculation model to establish the sound field grid model around the underwater vehicle, and set the acoustic parameters and structural material parameters. The frequency band acquisition module 400 is used to perform discrete Fourier transform on the preset time domain data, map the pressure pulsation data to the sound field grid model around the underwater vehicle, determine the calculation frequency band of the vibration noise, and calculate the sound pressure distribution around the underwater vehicle. The evaluation parameter acquisition module 500 is used to convert the sound pressure distribution into the sound source level, and calculate the total noise level of the whole frequency band and the single frequency point noise limit based on the calculation frequency band as the evaluation parameter. The evaluation module 600 is used to compare the evaluation parameter with the preset demand limit to determine whether it is satisfied. If not, iteratively execute steps S1-S6 to optimize the noise design of the preset drawing data and re-evaluate. Otherwise, the preset drawing data is feasible.

[0074] Furthermore, in one embodiment of the present invention, the distance between the inlet of the fluid domain in the geometric model construction module 100 and the bow of the underwater vehicle geometric model is greater than 6L, the distance between the outlet of the fluid domain and the stern of the underwater vehicle geometric model is greater than 10L, and the distance between the remaining boundaries of the fluid domain and the underwater vehicle geometric model is greater than 3L, where L is the total length of the underwater vehicle.

[0075] Furthermore, in one embodiment of the present invention, the bidirectional data transmission module 200 is specifically used for: determining a speed unit for determining the speed of an underwater vehicle of a geometric model of an underwater vehicle in a fluid domain; setting an interface unit for setting the surface of the geometric model of the underwater vehicle in the fluid domain and the surface of the geometric model of the underwater vehicle in the structural field as a fluid-solid coupling interface; a bidirectional data transmission unit for calculating the pulsating pressure of the fluid in the fluid domain on the structural surface using an implicit algorithm, and then transmitting the pulsating pressure data to the structural field, calculating the displacement of the structural surface in the structural field, and then transmitting the structural surface displacement to the fluid domain, updating the structural surface in the fluid domain, and obtaining pressure pulsation data.

[0076] Furthermore, in one embodiment of the present invention, the parameter setting module 300 is specifically used to: construct an acoustic calculation module unit for establishing an underwater vehicle acoustic calculation model in the computational acoustics software Virtual.Lab according to the structural finite element model; construct a sound field grid model unit for importing pressure pulsation data into the underwater vehicle acoustic calculation model to establish a sound field grid model around the underwater vehicle; set a parameter unit for establishing multiple noise monitoring points in the sound field grid model around the underwater vehicle according to preset analysis requirements, and set acoustic parameters and structural material parameters according to preset media.

[0077] It should be noted that the above explanation of an embodiment of a method for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-solid coupling is also applicable to the system of this embodiment and will not be repeated here.

[0078] The underwater vehicle flow-induced vibration and noise evaluation system considering fluid-solid coupling proposed in an embodiment of the present invention takes into account the influence of the fluid-solid coupling effect on the structure and flow field information, so that the prediction result when resonance occurs is more reliable, while ensuring the calculation efficiency, and has a guiding role in the protection design of low-frequency vibration noise. It can also perform a preliminary evaluation of the flow-induced vibration and noise of the underwater vehicle in the design stage, improve the rationality of the underwater vehicle design, and can be applied to the design and control of the flow-induced vibration and noise of large underwater vehicles.

[0079] In order to implement the above embodiments, the present invention also proposes a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-solid coupling as described in the above embodiments is implemented.

[0080] In order to implement the above embodiments, the present invention also proposes a non-temporary computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the method for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-solid coupling as described in the above embodiments is implemented.

[0081] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0082] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "N" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0083] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

[0084] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0085] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0086] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0087] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0088] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for evaluating flow-induced vibration noise of underwater vehicles considering fluid-structure coupling, characterized in that: The following steps are involved: Step S1, establishing an underwater vehicle geometric model according to preset drawing data, placing the underwater vehicle geometric model in a fluid domain, and establishing a fluid domain mesh model and a structural finite element model respectively according to the underwater vehicle geometric model; Step S2, determining the speed of the underwater vehicle, setting the fluid-solid coupling interface, using an implicit algorithm to perform bidirectional data transmission between the flow field and the structural field, and obtaining pressure pulsation data; Step S3, establishing an underwater vehicle acoustic calculation model based on the computational acoustics software Virtual.Lab, importing the pressure pulsation data into the underwater vehicle acoustic calculation model to establish a sound field grid model around the underwater vehicle, and setting acoustic parameters and structural material parameters; Step S4, performing discrete Fourier transform on the preset time domain data, mapping the pressure pulsation data onto a grid model of the sound field around the underwater vehicle, determining a calculation frequency band of the vibration noise, and calculating the sound pressure distribution around the underwater vehicle; Step S5, converting the sound pressure distribution into a sound source level, and calculating the total noise level of the entire frequency band and the single-frequency noise limit based on the calculation frequency band as evaluation parameters; Step S6, comparing the evaluation parameters with the preset demand limits to determine whether they are satisfied. If not, iteratively executing steps S1-S6 to perform noise optimization design on the preset drawing materials and re-evaluate. Otherwise, the preset drawing materials are feasible.

2. The method for evaluating flow-induced vibration noise of underwater vehicles considering fluid-structure coupling according to claim 1 is characterized in that: In the step S1, the distance between the inlet of the fluid domain and the bow of the underwater vehicle geometric model is greater than 6L, the distance between the outlet of the fluid domain and the stern of the underwater vehicle geometric model is greater than 10L, and the distance between the remaining boundaries of the fluid domain and the underwater vehicle geometric model is greater than 3L, wherein L is the total length of the underwater vehicle.

3. The method for evaluating flow-induced vibration noise of underwater vehicles considering fluid-structure coupling according to claim 1 is characterized in that: The step S2 specifically includes: Step S201, determining the underwater vehicle speed of the underwater vehicle geometric model in the fluid domain; Step S202, setting the surface of the underwater vehicle geometric model in the fluid domain and the surface of the underwater vehicle geometric model in the structure field as a fluid-solid coupling interface; Step S203, using an implicit algorithm to calculate the pulsating pressure of the fluid in the fluid domain on the structural surface, then transmitting the pulsating pressure data to the structural field, calculating the displacement of the structural surface in the structural field, and then transmitting the structural surface displacement to the fluid domain, updating the structural surface in the fluid domain, and obtaining the pressure pulsation data.

4. The method for evaluating flow-induced vibration noise of underwater vehicles considering fluid-structure coupling according to claim 1 is characterized in that: The step S3 specifically includes: Step S301, establishing the underwater vehicle acoustic computational model in the computational acoustics software Virtual.Lab according to the structural finite element model; Step S302, importing the pressure pulsation data into the underwater vehicle acoustic calculation model to establish a grid model of the sound field around the underwater vehicle; Step S303, establishing a plurality of noise monitoring points in the sound field grid model around the underwater vehicle according to preset analysis requirements, and setting the acoustic parameters and structural material parameters according to preset media.

5. A flow-induced vibration noise assessment system for underwater vehicles considering fluid-structure coupling, characterized in that: include: A geometric model building module is used to build an underwater vehicle geometric model according to preset drawing materials, place the underwater vehicle geometric model in a fluid domain, and respectively build a fluid domain mesh model and a structural finite element model according to the underwater vehicle geometric model; The two-way data transmission module is used to determine the speed of the underwater vehicle, set the fluid-solid coupling interface, use the implicit algorithm to perform two-way data transmission between the flow field and the structural field, and obtain the pressure pulsation data; A parameter setting module is used to establish an underwater vehicle acoustic calculation model based on the computational acoustics software Virtual.Lab, import the pressure pulsation data into the underwater vehicle acoustic calculation model to establish a sound field grid model around the underwater vehicle, and set acoustic parameters and structural material parameters; A frequency band acquisition module is used to perform discrete Fourier transform on preset time domain data, map the pressure pulsation data onto a grid model of the sound field around the underwater vehicle, determine the calculation frequency band of the vibration noise, and calculate the sound pressure distribution around the underwater vehicle; An evaluation parameter acquisition module is used to convert the sound pressure distribution into a sound source level, and calculate the total noise level of the entire frequency band and the single-frequency noise limit based on the calculation frequency band as evaluation parameters; The evaluation module is used to compare the evaluation parameters with the preset demand limits to determine whether they are met. If not, iteratively execute steps S1-S6 to perform noise optimization design on the preset drawing materials and re-evaluate. Otherwise, the preset drawing materials are feasible.

6. The underwater vehicle flow-induced vibration noise assessment system considering fluid-structure coupling according to claim 5 is characterized in that: In the geometric model construction module, the distance between the inlet of the fluid domain and the bow of the underwater vehicle geometric model is greater than 6L, the distance between the outlet of the fluid domain and the stern of the underwater vehicle geometric model is greater than 10L, and the distance between the remaining boundaries of the fluid domain and the underwater vehicle geometric model is greater than 3L, where L is the total length of the underwater vehicle.

7. The underwater vehicle flow-induced vibration noise evaluation system considering fluid-structure coupling according to claim 5 is characterized in that: The bidirectional data transmission module is specifically used for: A speed determination unit, used to determine the speed of the underwater vehicle of the underwater vehicle geometric model in the fluid domain; Setting an interface unit, for setting a surface of the underwater vehicle geometric model in the fluid domain and a surface of the underwater vehicle geometric model in the structure field as a fluid-solid coupling interface; A bidirectional data transmission unit is used to calculate the pulsating pressure of the fluid in the fluid domain on the structural surface by using an implicit algorithm, and then transmit the pulsating pressure data to the structural field, calculate the displacement of the structural surface in the structural field, and then transmit the structural surface displacement to the fluid domain, update the structural surface in the fluid domain, and obtain the pressure pulsation data.

8. The underwater vehicle flow-induced vibration and noise evaluation system considering fluid-structure coupling according to claim 5 is characterized in that: The parameter setting module is specifically used for: Constructing an acoustic calculation module unit for establishing the acoustic calculation model of the underwater vehicle in the computational acoustic software Virtual.Lab according to the structural finite element model; Constructing an acoustic field grid model unit, for importing the pressure pulsation data into the underwater vehicle acoustic calculation model to establish an acoustic field grid model around the underwater vehicle; The parameter setting unit is used to establish a plurality of noise monitoring points in the sound field grid model around the underwater vehicle according to preset analysis requirements, and to set the acoustic parameters and structural material parameters according to preset media.

9. A computer device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-solid coupling as claimed in any one of claims 1 to 4 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for evaluating flow-induced vibration noise of an underwater vehicle considering fluid-structure coupling as described in any one of claims 1 to 4 is implemented.

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