Charging Pile Noise Prediction Method and Device

Abstract

The present invention relates to the technical field of charging pile simulation, and provides a method and device for predicting the noise of a charging pile. The method includes the following steps: determining the noise parameters to be predicted; when the noise parameters to be predicted include frequency data, obtaining the frequency data through pneumatic noise calculation; and when it is necessary to quickly predict the sound pressure data of the noise, obtaining the sound pressure data through equivalent sound source substitution calculation. The present invention can conveniently and quickly realize the noise prediction of the charging pile.

Description

Technical Field

[0001] The present invention relates to the technical field of charging pile simulation, and particularly relates to a charging pile noise prediction method and a charging pile noise prediction device. Background Art

[0002] At present, with the development of new energy vehicles, more and more charging piles are built everywhere, and the noise problem of charging piles is becoming increasingly prominent. Especially for high-power charging piles, they generate a large amount of heat and require more and larger fans to ensure heat dissipation. Therefore, the fan noise in the charging pile has become the main source of the overall pile noise. Especially for charging piles near some residential buildings, the generated noise will seriously affect the lives of nearby residents. Therefore, before a charging pile is built and put into use, how to predict its noise has become an urgent problem to be solved. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention provides a charging pile noise prediction method and device, which can conveniently and quickly realize the noise prediction of the charging pile.

[0004] The technical solution adopted by the present invention is as follows:

[0005] A charging pile noise prediction method includes the following steps: determining the noise parameters to be predicted; when the noise parameters to be predicted include frequency data, obtaining the frequency data through aerodynamic noise calculation; when it is necessary to quickly predict the sound pressure data of the noise, obtaining the sound pressure data through equivalent sound source substitution calculation.

[0006] Obtaining the frequency data through aerodynamic noise calculation includes: obtaining the three-dimensional digital model of the fan in the charging pile and the three-dimensional digital model of the entire charging pile; establishing the entire charging pile flow field model according to the three-dimensional digital model of the fan in the charging pile and the three-dimensional digital model of the entire charging pile; obtaining the sound source data of the fan in the charging pile through the entire charging pile flow field model; establishing the entire charging pile acoustic model, mapping the sound source data of the fan in the charging pile to the entire charging pile acoustic model according to the corresponding coordinates, and performing acoustic solution to obtain the frequency data.

[0007] The sound source data of the fan in the charging pile is obtained through the overall pile flow field model of the charging pile, specifically including: obtaining the quantity of each type of fan in the charging pile; determining whether the quantity of the same type of fan is greater than a preset quantity; if the quantity of the same type of fan is not greater than the preset quantity, calculating and exporting the sound source data of each fan of this type, and mapping the sound source data of each fan to the coordinate position of the corresponding fan; if the quantity of the same type of fan is greater than the preset quantity, calculating and exporting the sound source data of any one fan of this type, and using the sound source data of this fan as the sound source data of all fans of this type and mapping it to the coordinate position of each fan.

[0008] The sound pressure data is obtained through equivalent sound source substitution calculation, including: substituting the fan sound source in the charging pile with a dipole sound source, and calculating the equivalent sound source parameters according to the sound propagation equation of the equivalent sound source; establishing the overall pile acoustic model of the charging pile, and using the equivalent sound source parameters as excitation parameters to perform acoustic solution to obtain the sound pressure data.

[0009] The sound propagation equation of the equivalent sound source is:

[0010]

[0011] where A is the equivalent sound source parameter, d is the distance from the air inlet surface to the air outlet surface of the fan, r is the distance from the fan to the receiving point, k is the acoustic wave number, and P i is the sound pressure amplitude at the receiving point.

[0012] A charging pile noise prediction device includes: a determination module for determining the noise parameters to be predicted; a first calculation module for obtaining the frequency data through aerodynamic noise calculation when the noise parameters to be predicted include frequency data; a second calculation module for obtaining the sound pressure data through equivalent sound source substitution calculation when quickly predicting the sound pressure data of the noise.

[0013] The first calculation module is used for: obtaining the three-dimensional digital model of the fan in the charging pile and the overall pile three-dimensional digital model of the charging pile; establishing the overall pile flow field model of the charging pile according to the three-dimensional digital model of the fan in the charging pile and the overall pile three-dimensional digital model of the charging pile; obtaining the sound source data of the fan in the charging pile through the overall pile flow field model of the charging pile; establishing the overall pile acoustic model of the charging pile, and mapping the sound source data of the fan in the charging pile to the overall pile acoustic model of the charging pile according to the corresponding coordinates, and performing acoustic solution to obtain the frequency data.

[0014] The first calculation module is specifically configured to: obtain the quantity of each type of fan in the charging pile; determine whether the quantity of the same type of fan is greater than a preset quantity; if the quantity of the same type of fan is not greater than the preset quantity, calculate and export the sound source data of each fan of this type, and map the sound source data of each fan to the corresponding coordinate position of each fan; if the quantity of the same type of fan is greater than the preset quantity, calculate and export the sound source data of any one fan of this type, and use the sound source data of this fan as the sound source data of all fans of this type and map it to the coordinate position of each fan.

[0015] The second calculation module is configured to: replace the fan sound source in the charging pile with a dipole sound source, and calculate the equivalent sound source parameters according to the sound propagation equation of the equivalent sound source; establish an acoustic model of the entire charging pile, and use the equivalent sound source parameters as excitation parameters to perform acoustic solution to obtain the sound pressure data.

[0016] The sound propagation equation of the equivalent sound source is:

[0017]

[0018] where A is the equivalent sound source parameter, d is the distance from the air inlet surface to the air outlet surface of the fan, r is the distance from the fan to the receiving point, k is the wave number of the sound wave, and P i is the sound pressure amplitude at the receiving point.

[0019] Advantages of the present invention:

[0020] By predicting the sound pressure and frequency data of the charging pile noise, the present invention can not only intuitively reflect the noise level of the entire pile through the sound pressure data, but also provide a data basis for subsequent noise reduction design and processing through the frequency data. Moreover, when it is necessary to quickly predict the sound pressure data of the charging pile noise, it can be achieved through equivalent sound source substitution calculation. Compared with using hydrodynamics and aeroacoustics calculations, it can greatly save computing resources and reduce computing time, so as to realize the noise prediction of the charging pile as conveniently and quickly as possible. Description of the drawings

[0021] Figure 1 is a flowchart of the method for predicting the charging pile noise in an embodiment of the present invention;

[0022] Figure 2 is a specific flowchart of obtaining frequency data through aerodynamic noise calculation in an embodiment of the present invention;

[0023] Figure 3 is a specific flowchart of obtaining sound pressure data through equivalent sound source substitution calculation in an embodiment of the present invention;

[0024] Figure 4It is a block diagram of the charging pile noise prediction device according to an embodiment of the present invention. Specific embodiments

[0025] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the 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.

[0026] As Figure 1 shown, the charging pile noise prediction method according to an embodiment of the present invention includes the following steps: S1, determining the noise parameters to be predicted. S2, when the noise parameters to be predicted include frequency data, obtaining the frequency data through aerodynamic noise calculation. S3, when it is necessary to quickly predict the sound pressure data of the noise, obtaining the sound pressure data through equivalent sound source substitution calculation.

[0027] According to the charging pile noise prediction method of the embodiment of the present invention, by predicting the sound pressure and frequency data of the charging pile noise, it can not only intuitively reflect the noise level of the entire pile through the sound pressure data, but also provide a data basis for subsequent noise reduction design and processing through the frequency data. Moreover, when it is necessary to quickly predict the sound pressure data of the charging pile noise, it can be achieved through equivalent sound source substitution calculation. Compared with using fluid mechanics and aeroacoustics calculations, it can greatly save computing resources and reduce computing time, thereby realizing the noise prediction of the charging pile as conveniently and quickly as possible.

[0028] In an embodiment of the present invention, as Figure 2 shown, obtaining the frequency data through aerodynamic noise calculation includes:

[0029] S21, obtaining the three-dimensional digital model of the fan in the charging pile and the three-dimensional digital model of the entire charging pile.

[0030] When calculating the frequency data of its noise through aerodynamic noise, first, the three-dimensional digital models of the entire pile and the fan can be obtained. The three-dimensional digital models of the entire pile and the fan can be obtained from the product design database. If the fan is provided by an external supplier, the fan can be reversely scanned to obtain the three-dimensional digital model of the fan.

[0031] S22, establishing the entire pile flow field model of the charging pile according to the three-dimensional digital model of the fan in the charging pile and the three-dimensional digital model of the entire charging pile.

[0032] The three-dimensional digital models of each fan can be assembled into the three-dimensional digital model of the entire pile according to the actual positions, and then the three-dimensional digital model can be simplified into a calculable fluid domain model, that is, the entire pile flow field model of the charging pile is obtained.

[0033] S23. Obtain the sound source data of the fan in the charging pile through the overall charging pile flow field model of the charging pile.

[0034] By solving the overall charging pile flow field model of the charging pile, the air flow information inside the overall charging pile can be obtained. Export the time-domain data of the pressure and velocity of each fan, which can be used as the sound source data of the fan.

[0035] Since there are multiple fans with the same model in a charging pile, that is, the same model of fans, it is not necessary to export the sound source data of each fan. In an embodiment of the present invention, the number of each type of fan in the charging pile can be obtained, and it is determined whether the number of the same model of fans is greater than a preset number. If the number of the same model of fans is not greater than the preset number, calculate and export the sound source data of each fan of this type, and map the sound source data of each fan to the corresponding coordinate position of each fan; if the number of the same model of fans is greater than the preset number, calculate and export the sound source data of any one fan of this type, and use the sound source data of this fan as the sound source data of all fans of this type and map it to the coordinate position of each fan.

[0036] That is to say, in view of the fact that the sound source data of the same model of fans is basically the same, if the total number of a certain type of fan in the charging pile is small, the sound source data of all its fans can be directly exported; if the total number of a certain type of fan in the charging pile is large, only the sound source data of one of the fans can be exported, and it is used as the sound source data of all fans of this type. In the acoustic model of the subsequent step S24, map the sound source data according to the coordinates of each fan.

[0037] In the embodiment of the present invention, by only exporting the sound source data of one of the fans when the number of the same model of fans is large, the amount of data to be processed can be effectively reduced, and the complexity of the construction and solution of the subsequent overall charging pile acoustic model can be reduced, thereby improving the efficiency of aerodynamic noise calculation and more conveniently and quickly realizing the noise prediction of the charging pile.

[0038] It should be understood that the preset number can be set according to the amount of data of the exported sound source data, so that the data size of exporting the sound source data of all fans of the same model is within an acceptable range. In a specific embodiment of the present invention, the preset number can be 4. Taking the noise prediction of a 120kW DC charging pile as an example, this charging pile has a total of 16 fans, including 12 heat dissipation fans (module fans) of the same model for the charging module and 4 heat dissipation fans (system fans) of the same model for the overall charging pile system. Then for the system fans, the sound source data of each system fan can be exported, and for the module fans, only the sound source data of one module fan can be exported, and this sound source data is also used as the sound source data of the other 11 module fans.

[0039] S24. Establish the overall pile acoustic model of the charging pile, map the sound source data of the fan in the charging pile to the overall pile acoustic model of the charging pile according to the corresponding coordinates, and perform acoustic solution to obtain frequency data.

[0040] In an embodiment of the present invention, the overall pile acoustic model of the charging pile can be established through the pre-processing software ANSA, and the sound source data of the fan obtained in step S23 is mapped to the coordinate position of the corresponding fan in the acoustic model, and the sound source data of the fan is transmitted to the acoustic model. As described above, when the number of the same type of fans is greater than the preset number, only the sound source data of one fan is exported, and through coordinate transformation, it is repeatedly mapped to the positions of each same type of fan, so as to obtain the overall pile acoustic model including all the sound source data of the fans.

[0041] In an embodiment of the present invention, the mapping of grid nodes is adopted for the sound source data, that is, the sound source data on the grid nodes of the overall pile flow field model is mapped to the corresponding grid nodes of the overall pile acoustic model.

[0042] After obtaining the overall pile acoustic model including all the sound source data of the fans, the sound propagation calculation is carried out through an acoustic solver to obtain the frequency data of the noise of the charging pile in the simulation scenario, including spectrum information, main frequency band, etc., realizing the prediction of the frequency data of the charging pile noise.

[0043] In most cases, it is necessary to quickly understand the noise conditions of the charging pile under multiple different working conditions. At this time, only the specific sound pressure values of the overall pile under different working conditions need to be known, so as to judge the maximum noise level of the overall pile. However, the above-mentioned calculation of aerodynamic noise for multiple working conditions cannot well meet the requirements of rapid prediction in engineering. In view of this, the embodiment of the present invention can also obtain the sound pressure data through equivalent sound source substitution calculation.

[0044] In an embodiment of the present invention, as Figure 3 shown, obtaining the sound pressure data through equivalent sound source substitution calculation includes:

[0045] S31. Substitute the fan sound source in the charging pile with a dipole sound source, and calculate the equivalent sound source parameters according to the sound propagation equation of the equivalent sound source.

[0046] The main sound source in the charging pile is the axial flow fan. Due to the particularity of the noise propagation mode of the axial flow fan, its noise mainly propagates to the outside through the air inlet and outlet of the fan, and the noise propagation in other directions contributes less compared with these two directions. In view of the noise propagation characteristics of the fan, the embodiment of the present invention adopts the equivalence of the dipole sound source, so as to simulate the sound generation mode of the fan sound source more accurately.

[0047] In an embodiment of the present invention, the following sound propagation equation of the equivalent sound source can be established:

[0048]

[0049] Among them, A is the equivalent sound source parameter, d is the distance from the air inlet surface to the air outlet surface of the fan, r is the distance from the fan to the receiving point, k is the acoustic wave number, and P i is the sound pressure amplitude at the receiving point.

[0050] Through the above acoustic propagation equation of the equivalent sound source, the equivalent sound source parameters of the fan can be calculated. The equivalent sound source parameter is the sound source amplitude, which is a complex number. It can be considered that the fan sound source is composed of two spherical sound sources with the same intensity propagating towards the air inlet and outlet respectively, and the real part of the sound source parameter is equivalent to the positive direction, while the imaginary part is the opposite direction.

[0051] In a specific embodiment of the present invention, assume that the maximum noise values of each fan are obtained by referring to the fan specification sheet. Among them, the maximum noise value of the module fan is 60.1 dBA, and the maximum noise value of the system fan is 70 dBA. First, according to the above acoustic propagation equation of the equivalent sound source, the equivalent sound source parameter A of the module fan is inversely deduced M , where the sound pressure level at the receiving point 1 meter away from the module fan is 60.1 dBA, which is converted to the sound pressure amplitude P iM = 0.02 Pa, the distance r between the simulation receiving point and the sound source is 1 m, the distance d between the air inlet and outlet of the module fan M = 0.024 m, the acoustic wave number k = 2πf / c, f is the calculated frequency, and c is the sound speed = 340 m / s. Finally, the equivalent sound source parameter A of the module fan is obtained according to the equation M = 0.85 - 0.85i. Similarly, the equivalent sound source parameter A of the system fan can be obtained X . The equivalent sound source parameters under other working conditions are also inversely deduced in this way. In this embodiment, the noise sound pressure values at the receiving points of the whole pile of the system fan at different speeds can be calculated when the speed of the module fan remains unchanged.

[0052] S32. Establish the whole-pile acoustic model of the charging pile, and use the equivalent sound source parameter as the excitation parameter to perform acoustic solution to obtain the sound pressure data.

[0053] In a specific embodiment of the present invention, after establishing the whole-pile acoustic model of the charging pile, the above two equivalent sound source parameters A M and A X can be loaded to the corresponding fan coordinate positions in the form of ideal volume sound sources respectively, and then the sound propagation solution is carried out to obtain the sound pressure value of the charging pile noise in the simulation scenario, and further obtain the sound pressure level of the charging pile noise, realizing the prediction of the sound pressure data of the charging pile noise. [[ID=--33]]

[0054] The embodiments of the present invention adopt equivalent sound source substitution calculation, which can not only save computing resources and reduce computing time, but also efficiently obtain the sound pressure level caused by the interaction of different models of fans, providing an effective means for the selection and combination of the entire pile of fans.

[0055] Corresponding to the charging pile noise prediction method of the above embodiment, the present invention also proposes a charging pile noise prediction device.

[0056] As Figure 4 shown, the charging pile noise prediction device of the embodiments of the present invention includes a determination module 10, a first calculation module 20 and a second calculation module 30. Among them, the determination module 10 is used to determine the noise parameters to be predicted; the first calculation module 20 is used to obtain frequency data through aerodynamic noise calculation when the noise parameters to be predicted include frequency data; the second calculation module 30 is used to obtain sound pressure data through equivalent sound source substitution calculation when quickly predicting the sound pressure data of the noise.

[0057] According to the charging pile noise prediction device of the embodiments of the present invention, by predicting the sound pressure and frequency data of the charging pile noise, it can not only intuitively reflect the noise level of the entire pile through the sound pressure data, but also provide data basis for subsequent noise reduction design and processing through the frequency data. Moreover, when the sound pressure data of the charging pile noise needs to be quickly predicted, it can be achieved through equivalent sound source substitution calculation. Compared with using fluid mechanics and aeroacoustics calculations, it can greatly save computing resources and reduce computing time, thus realizing the noise prediction of the charging pile as conveniently and quickly as possible.

[0058] In an embodiment of the present invention, the first calculation module 20 is used to: obtain the three-dimensional digital model of the fan in the charging pile and the three-dimensional digital model of the entire pile of the charging pile; establish the entire pile flow field model of the charging pile according to the three-dimensional digital model of the fan in the charging pile and the three-dimensional digital model of the entire pile of the charging pile; obtain the sound source data of the fan in the charging pile through the entire pile flow field model of the charging pile; establish the entire pile acoustic model of the charging pile, and map the sound source data of the fan in the charging pile to the entire pile acoustic model of the charging pile according to the corresponding coordinates, and perform acoustic solution to obtain frequency data.

[0059] When the first calculation module 20 calculates the frequency data of its noise through aerodynamic noise, first, the three-dimensional digital models of the entire pile and the fan can be obtained. The three-dimensional digital models of the entire pile and the fan can be obtained from the product design database. If the fan is provided by an external supplier, the fan can be reversely scanned to obtain the three-dimensional digital model of the fan.

[0060] The three-dimensional digital models of each fan can be assembled into the three-dimensional digital model of the entire pile according to the actual position, and then the three-dimensional digital model can be simplified into a computable fluid domain model, that is, the entire pile flow field model of the charging pile is obtained.

[0061] By solving the overall pile flow field model of the charging pile, the air flow information inside the overall pile can be obtained. Exporting the time-domain data of the pressure and velocity of each fan can be used as the sound source data of the fan.

[0062] Since there are multiple fans of the same model in a charging pile, that is, the same type of fan, it is not necessary to export the sound source data of each fan. In an embodiment of the present invention, the first calculation module 20 can obtain the number of each type of fan in the charging pile and determine whether the number of the same type of fan is greater than a preset number. If the number of the same type of fan is not greater than the preset number, calculate and export the sound source data of each fan of this type, and map the sound source data of each fan to the corresponding coordinate position of each fan; if the number of the same type of fan is greater than the preset number, calculate and export the sound source data of any one fan of this type, and use the sound source data of this fan as the sound source data of all fans of this type and map it to the coordinate position of each fan.

[0063] That is to say, in view of the fact that the sound source data of the same type of fan is basically the same, if the total number of a certain type of fan in the charging pile is small, the sound source data of all its fans can be directly exported; if the total number of a certain type of fan in the charging pile is large, only the sound source data of one of the fans can be exported and used as the sound source data of all fans of this type. In the subsequent acoustic model, map the sound source data according to the coordinates of each fan.

[0064] In the embodiment of the present invention, by only exporting the sound source data of one of the fans when the number of the same type of fans is large, it can effectively reduce the amount of data to be processed, reduce the complexity of the construction and solution of the subsequent overall pile acoustic model, thereby improving the efficiency of aerodynamic noise calculation and more conveniently and quickly realizing the noise prediction of the charging pile.

[0065] It should be understood that the preset number can be set according to the amount of data of the exported sound source data, so that the data size of exporting the sound source data of all fans of the same type is within an acceptable range. In a specific embodiment of the present invention, the preset number can be 4. Taking the noise prediction of a 120kW DC charging pile as an example, this charging pile has a total of 16 fans, including 12 heat dissipation fans (module fans) of the same model for the charging modules and 4 heat dissipation fans (system fans) of the same model for the overall pile system. Then for the system fans, the sound source data of each system fan can be exported, and for the module fans, only the sound source data of one module fan can be exported, and this sound source data is also used as the sound source data of the other 11 module fans.

[0066] In an embodiment of the present invention, the overall pile acoustic model of the charging pile can be established through the pre-processing software ANSA, and the obtained sound source data of the fan is mapped to the coordinate position of the corresponding fan in the acoustic model, and the sound source data of the fan is transmitted to the acoustic model. As described above, when the number of the same type of fans is greater than the preset number, only the sound source data of one fan is exported, and through coordinate transformation, it is repeatedly mapped to the positions of each same type of fan, so as to obtain the overall pile acoustic model containing all the sound source data of the fans.

[0067] In an embodiment of the present invention, the sound source data uses the mapping of grid nodes, that is, the sound source data on the grid nodes of the overall pile flow field model is mapped to the corresponding grid nodes of the overall pile acoustic model.

[0068] After obtaining the overall pile acoustic model containing all the sound source data of the fans, the sound propagation calculation is carried out through the acoustic solver to obtain the frequency data of the charging pile noise in the simulation scenario, including spectrum information, main frequency band, etc., realizing the prediction of the charging pile noise frequency data.

[0069] In most cases, it is necessary to quickly understand the noise conditions of the charging pile under multiple different working conditions. At this time, only the specific sound pressure values of the overall pile under different working conditions are required to judge the maximum noise level of the overall pile. However, the above-mentioned calculation of the aerodynamic noise for multiple working conditions cannot well meet the requirements of rapid prediction in engineering. In view of this, the embodiment of the present invention can also obtain the sound pressure data through the equivalent sound source substitution calculation of the second calculation module.

[0070] In an embodiment of the present invention, the second calculation module 30 is used for: replacing the fan sound source in the charging pile with a dipole sound source, and calculating the equivalent sound source parameters according to the sound propagation equation of the equivalent sound source; establishing the overall pile acoustic model of the charging pile, and using the equivalent sound source parameters as the excitation parameters to perform acoustic solution to obtain the sound pressure data.

[0071] The main sound source in the charging pile is the axial flow fan. Due to the particularity of the noise propagation mode of the axial flow fan, its noise mainly propagates to the outside through the air inlet and outlet of the fan. The noise propagation in other directions contributes less compared to these two directions. In view of the noise propagation characteristics of the fan, the embodiment of the present invention adopts the equivalence of the dipole sound source, so as to more accurately simulate the sound generation mode of the fan sound source.

[0072] In an embodiment of the present invention, the following sound propagation equation of the equivalent sound source can be established:

[0073]

[0074] Among them, A is the equivalent sound source parameter, d is the distance from the air inlet surface of the fan to the air outlet surface, r is the distance from the fan to the receiving point, k is the acoustic wave number, P iis the sound pressure amplitude at the receiving point.

[0075] Through the above sound propagation equation of the equivalent sound source, the equivalent sound source parameters of the fan can be calculated. The equivalent sound source parameter is the sound source amplitude, which is a complex number. It can be considered that the fan sound source is composed of two spherical sound sources of the same intensity propagating towards the inlet and outlet respectively, and the real part of the sound source parameter is equivalent to the positive direction, and the imaginary part is the opposite direction.

[0076] In a specific embodiment of the present invention, assume that the maximum noise values of each fan are obtained by consulting the fan specification sheet. The maximum noise value of the module fan is 60.1 dBA, and the maximum noise value of the system fan is 70 dBA. First, according to the above sound propagation equation of the equivalent sound source, the equivalent sound source parameter A of the module fan is deduced backwards M , where the sound pressure level at the receiving point 1 meter away from the module fan is 60.1 dBA, which is converted to the sound pressure amplitude P iM = 0.02 Pa, the distance r between the simulation receiving point and the sound source is 1 m, the distance d between the inlet and outlet of the module fan M = 0.024 m, the acoustic wave number k = 2πf / c, f is the calculated frequency, c is the sound speed = 340 m / s, and finally the equivalent sound source parameter A of the module fan is obtained according to the equation M = 0.85 - 0.85i. Similarly, the equivalent sound source parameter A of the system fan can be obtained X . The equivalent sound source parameters under other working conditions are also deduced in this way. In this embodiment, the noise sound pressure values at the receiving points of the whole pile of the system fan at different speeds can be calculated when the speed of the module fan remains unchanged.

[0077] In a specific embodiment of the present invention, after establishing the whole-pile acoustic model of the charging pile, the above two equivalent sound source parameters A M and A X can be loaded into the corresponding fan coordinate positions in the form of ideal volume sound sources respectively, and then the sound propagation is solved to obtain the sound pressure value of the charging pile noise in the simulation scenario, and then the sound pressure level of the charging pile noise is obtained, realizing the prediction of the sound pressure data of the charging pile noise.

[0078] The embodiment of the present invention uses equivalent sound source substitution calculation, which can not only save computing resources and reduce computing time, but also efficiently obtain the sound pressure level caused by the interaction of different types of fans, providing an effective means for the selection and combination of the whole-pile fans.

[0079] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. The meaning of "plurality" is two or more, unless specifically and clearly defined otherwise.

[0080] In the present invention, unless otherwise clearly specified and defined, terms such as "installed", "connected", "joined", "fixed", etc. shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal connection or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0081] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0082] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions 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 a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0083] Any process or method description represented in a flowchart or otherwise described herein can be understood to represent a module, segment, or portion of code including one or more executable instructions for implementing a specific logical function or process. The scope of the preferred embodiments of the present invention includes additional implementations where functions may be executed not in the order shown or discussed, including in a substantially simultaneous manner according to the involved functions or in a reverse order, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0084] The logic and / or steps represented in a flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing a logical function, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in conjunction with such instruction execution systems, apparatus, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then storing it in a computer memory.

[0085] It should be understood that various parts of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, multiple 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, any one of the following techniques known in the art or a combination thereof can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits having suitable combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0086] Those of ordinary skill in the art can understand that all or part of the steps carried out in implementing the above method embodiments can be completed by instructing relevant hardware through a program. The said program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

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

[0088] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limitations of the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A charging pile noise prediction method, characterized in that: The following steps are involved: Determine the noise parameters to be predicted; When the noise parameter to be predicted includes frequency data, the frequency data is obtained by aerodynamic noise calculation; When the sound pressure data of the noise needs to be predicted quickly, the sound pressure data is obtained by equivalent sound source substitution calculation. The frequency data is obtained by calculating aerodynamic noise, including: obtaining a three-dimensional digital model of the fan in the charging pile and a three-dimensional digital model of the entire charging pile; establishing a flow field model of the entire charging pile according to the three-dimensional digital model of the fan in the charging pile and the three-dimensional digital model of the entire charging pile; obtaining the sound source data of the fan in the charging pile through the flow field model of the entire charging pile; establishing an acoustic model of the entire charging pile, and mapping the sound source data of the fan in the charging pile to the acoustic model of the entire charging pile according to corresponding coordinates, performing acoustic solution, and obtaining the frequency data. The sound pressure data is obtained by equivalent sound source replacement calculation, including: replacing the fan sound source in the charging pile with a dipole sound source, and calculating the equivalent sound source parameters according to the sound propagation equation of the equivalent sound source; establishing an acoustic model of the entire charging pile, and using the equivalent sound source parameters as excitation parameters to perform acoustic solution to obtain the sound pressure data, The sound propagation equation of the equivalent sound source is: Wherein, A is the equivalent sound source parameter, d is the distance from the fan inlet to the outlet, r is the distance from the fan to the receiving point, k is the sound wave number, P i is the sound pressure amplitude at the receiving point.

2. The charging pile noise prediction method according to claim 1, characterized in that: The sound source data of the fan in the charging pile is obtained through the flow field model of the entire charging pile, specifically including: Obtain the quantity of each type of wind turbine in the charging pile; Determine whether the number of fans of the same model is greater than the preset number; If the number of fans of the same type is not greater than the preset number, then calculating and exporting the sound source data of each fan of the same type, and mapping the sound source data of each fan to the coordinate position of each corresponding fan; If the number of fans of the same type is greater than the preset number, the sound source data of any one fan of the type is calculated and exported, and the sound source data of the fan is used as the sound source data of all fans of the type and mapped to the coordinate position of each fan.

3. A charging pile noise prediction device, characterized in that: include: A determination module, used for determining the noise parameters to be predicted; a first calculation module, configured to obtain the frequency data by aerodynamic noise calculation when the noise parameter to be predicted includes frequency data; The second calculation module is used to obtain the sound pressure data by equivalent sound source substitution calculation when quickly predicting the sound pressure data of the noise, The first calculation module is used to: obtain the three-dimensional digital model of the fan in the charging pile and the three-dimensional digital model of the entire charging pile; establish the entire flow field model of the charging pile according to the three-dimensional digital model of the fan in the charging pile and the three-dimensional digital model of the entire charging pile; obtain the sound source data of the fan in the charging pile through the entire flow field model of the charging pile; establish the entire acoustic model of the charging pile, and map the sound source data of the fan in the charging pile to the entire acoustic model of the charging pile according to the corresponding coordinates, perform acoustic solution, and obtain the frequency data. The second calculation module is used to: replace the fan sound source in the charging pile with a dipole sound source, and calculate the equivalent sound source parameters according to the sound propagation equation of the equivalent sound source; establish an acoustic model of the entire charging pile, and use the equivalent sound source parameters as excitation parameters to perform acoustic solution to obtain the sound pressure data. The sound propagation equation of the equivalent sound source is: Wherein, A is the equivalent sound source parameter, d is the distance from the fan inlet to the outlet, r is the distance from the fan to the receiving point, k is the sound wave number, P i is the sound pressure amplitude at the receiving point.

4. The charging pile noise prediction device according to claim 3, characterized in that: The first calculation module is specifically configured to: Obtain the quantity of each type of wind turbine in the charging pile; Determine whether the number of fans of the same model is greater than the preset number; If the number of fans of the same type is not greater than the preset number, then calculating and exporting the sound source data of each fan of the same type, and mapping the sound source data of each fan to the coordinate position of each corresponding fan; If the number of fans of the same type is greater than the preset number, the sound source data of any one fan of the type is calculated and exported, and the sound source data of the fan is used as the sound source data of all fans of the type and mapped to the coordinate position of each fan.

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