CN114519286B - Method for rapidly calculating secondary structural noise of vibration caused by rail transit vehicle - Google Patents
Method for rapidly calculating secondary structural noise of vibration caused by rail transit vehicle Download PDFInfo
- Publication number
- CN114519286B CN114519286B CN202210147751.0A CN202210147751A CN114519286B CN 114519286 B CN114519286 B CN 114519286B CN 202210147751 A CN202210147751 A CN 202210147751A CN 114519286 B CN114519286 B CN 114519286B
- Authority
- CN
- China
- Prior art keywords
- vibration
- evaluation point
- noise
- result
- point grid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/23—Design optimisation, verification or simulation using finite element methods [FEM] or finite difference methods [FDM]
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/13—Architectural design, e.g. computer-aided architectural design [CAAD] related to design of buildings, bridges, landscapes, production plants or roads
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F8/00—Arrangements for software engineering
- G06F8/40—Transformation of program code
- G06F8/41—Compilation
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Geometry (AREA)
- General Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Computational Mathematics (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- Pure & Applied Mathematics (AREA)
- Software Systems (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
Abstract
The invention relates to the field of rail transit, and discloses a method for rapidly calculating secondary structural noise of vibration caused by a rail transit vehicle. When the vehicle-induced vibration is calculated, the whole ultra-large-scale building finite element model is discretized, only the vibration result of the evaluation point grid set defined in advance is calculated and output, the evaluation point grid set and the vibration result thereof in the vibration analysis model are transplanted to the acoustic radiation calculation model, and the secondary structural noise is solved in the frequency domain by utilizing the self-adaptive order finite element technology, so that the problems of the along-line environment/building vehicle-induced vibration and the secondary structural noise caused by the rapid calculation of the rail traffic are solved, the calculation time is shortened, and the calculation cost is reduced.
Description
Technical Field
The invention relates to the field of rail transit, in particular to a method for rapidly calculating secondary structural noise of building vehicle-induced vibration radiation caused by rail transit.
Background
Along with the rapid development of rail transit such as high-speed rails and subways, a green efficient development mode of 'rail-city' fusion development is gradually formed, and the problems of vehicle-induced vibration and secondary structural noise generated along the environment and buildings when a train passes through are gradually emerging. Long-term train loading can affect structural safety; in addition, the building components vibrate under the action of train load to radiate low-frequency structural noise, and compared with high-frequency noise, the building components are more prone to producing long-term health hazards to people. At present, a time-course finite element calculation method is widely applied to prediction research of vibration and secondary structural noise caused by track traffic along a line environment/building vehicle.
As shown in fig. 1, the main idea of the time-course finite element analysis method (Finite Element Method, FEM) is to obtain the train load through a "train-track" model, and then obtain the time-course train induced vibration response through a "track-soil-building" model. The secondary structural noise is calculated by an acoustic boundary element/finite element method on the basis of acquiring the building vibration response. The finite element method can describe the detail characteristics of main vibration links such as a track, a line, a soil layer, a building structure and the like more truly and specifically, but because the structure form of an actual research object is complex, the space scale is huge, and the time cost required for constructing and solving the models is very expensive.
Therefore, a rapid and accurate method for calculating the noise of the vehicle-induced vibration secondary structure is urgently needed.
Disclosure of Invention
The invention aims to provide a method for rapidly calculating secondary structural noise of vibration caused by a rail transit vehicle.
The invention discloses a method for rapidly calculating secondary structural noise of vibration caused by a rail transit vehicle, which is characterized by comprising the following steps:
in the vibration analysis model, the whole building finite element model is discretized into a plurality of grid groups, the grid groups needing to evaluate the secondary structural noise are defined as evaluation point grid groups, the types of results needing to be output by the evaluation point grid groups are defined, and vibration result files of the evaluation point grid groups are calculated and output;
and transplanting the vibration result of the evaluation point grid group to an acoustic radiation calculation model, and calculating secondary structural noise in a frequency domain.
Further, after the vibration result file of the evaluation point grid set is output, the vibration result file of the evaluation point grid set is compiled for the second time, so that the vibration result file of the evaluation point grid set is integrated again, and the vibration result of the evaluation point grid set is transplanted to the acoustic radiation calculation model.
Further, the vibration result file of the evaluation point grid set includes a node number, a coordinate position, and a time-course vibration result on each unit node in the evaluation point grid set.
Further, when the vibration result file of the evaluation point grid set is compiled secondarily, a finite element grid consistent with the evaluation point grid set of the vibration analysis model is generated on the acoustic radiation calculation model by using the node numbers and the coordinate positions, and the time-course vibration result on each unit node is in one-to-one correspondence to the finite element grid of the acoustic radiation calculation model.
Further, a vibration-noise data interface is developed, and a vibration result file of the evaluation point grid set is compiled for the second time.
Further, the time-frequency conversion of the vibration response is completed by performing Fourier transform on the time-frequency vibration result to generate a frequency domain vibration result, and the frequency domain vibration result is then corresponding to the finite element grid of the acoustic radiation calculation model.
Further, when the secondary structure noise is calculated, an acoustic calculation domain mesh is generated, and the frequency domain vibration result is mapped onto the acoustic calculation domain mesh surface.
Generating a field point grid for outputting a noise calculation result;
further, the adaptive order finite element technique is applied to rapidly calculate the secondary structural noise in the frequency domain.
Further, the time course vibration results include vertical vibration displacement, velocity, and acceleration.
Further, after the secondary structure noise is calculated, the noise result of the derived evaluation point comprises a frequency spectrum, an equivalent A sound level and a sound pressure distribution cloud chart of noise characteristics, wherein the noise characteristics comprise sound pressure, sound pressure level, sound power and sound power level.
Further, when the secondary structure noise is calculated, an adaptive order finite element technology is adopted for calculation.
The beneficial effects of the invention are as follows: when the vehicle-induced vibration is calculated, the whole ultra-large building finite element model is discretized, only the vibration result of the evaluation point grid set defined in advance is output, the evaluation point grid set and the vibration result thereof in the vibration analysis model are transplanted to the acoustic radiation calculation model, and the secondary structural noise is solved in the frequency domain by utilizing the self-adaptive order finite element technology, so that the problems of the along-line environment/building vehicle-induced vibration and the secondary structural noise caused by the rapid calculation of the rail traffic are solved, the calculation time can be shortened, and the calculation cost is reduced.
Drawings
FIG. 1 is a schematic diagram of a prior art secondary structure noise prediction flow;
FIG. 2 is a schematic diagram of a secondary structure noise fast calculation flow of the present application;
FIG. 3 is a schematic illustration of a set of evaluation point grids in the present application;
FIG. 4 is a schematic illustration of a "track-soil-building" model in an embodiment;
FIG. 5 is a comparison of example vibration calculations with test data;
fig. 6 is a comparison of the noise calculation results with the published literature results in the example.
Detailed Description
The invention is further described below.
The invention discloses a method for rapidly calculating secondary structural noise of vibration caused by a rail transit vehicle, which comprises the following steps:
in the vibration analysis model, the whole building finite element model is discretized into a plurality of grid groups, the grid groups needing to evaluate the secondary structural noise are defined as evaluation point grid groups, the types of results needing to be output by the evaluation point grid groups are defined, and vibration result files of the evaluation point grid groups are calculated and output;
and transplanting the vibration result of the evaluation point grid group to an acoustic radiation calculation model, and calculating secondary structural noise in a frequency domain.
The vibration analysis model is usually built in vibration analysis software, which is a tool for dividing the grid group of sensitive buildings along the track traffic, defining the type of output result and calculating the vehicle-induced vibration response. The vibration analysis software may employ GTS Midas, etc. After a complete track-soil body-building finite element model is established in vibration analysis software, an evaluation point grid set is defined according to vibration noise evaluation requirements, namely, the grid set where the area with the vibration and secondary structure noise level is required to be evaluated is, as shown in fig. 3, the number of grids/nodes is far smaller than that of the whole building finite element model, and the calculation time for performing time-course vibration response can be saved. And then defining the content of a result output file, determining the type of the result according to the calculation requirement of the subsequent secondary noise, carrying out time-course vibration analysis after the content is defined, and only calculating and outputting the vibration result defined in the evaluation point grid group, thereby avoiding the high calculation cost caused by solving and outputting various dynamic response parameters of the ultra-large scale building finite element model.
The calculation of the secondary structural noise is required to be completed on an acoustic radiation calculation model which is usually established in noise analysis software, and therefore, the vibration result of the evaluation point grid set is transplanted to the acoustic radiation calculation model to perform the secondary structural noise calculation. The noise analysis software may employ LMS Virtual lab, etc. The secondary structure noise may be calculated in the frequency domain using an adaptive order finite element technique (Finite Element Method Adaptive Order, FEMAO). The adaptive order finite element technique can automatically adjust the mesh order according to the calculated frequency, and properly relax the acoustic mesh size to reduce the number of meshes, thereby reducing the solving time.
The type of the vibration result file output by the vibration analysis software is defined in advance according to the requirement, so that the vibration result file can be defined according to the information and the format required by the noise analysis software, however, in most cases, the vibration result of the self-defined evaluation point grid set output by the vibration analysis software is discrete, and the vibration result file format cannot be directly read by the noise analysis software. Therefore, the vibration result file of the evaluation point grid set is preferably compiled for a second time so as to be re-integrated, so that the vibration result of the evaluation point grid set can be transplanted to the acoustic radiation calculation model.
The vibration result file of the evaluation point grid set is determined according to data required for calculation of the quadratic noise, for example, in a preferred embodiment of the present application, the vibration result file of the evaluation point grid set includes a node number, a coordinate position of each unit node within the grid set, and a time-course vibration result on each unit node. Such as the number (1, 2, …, n) of each node, the coordinates (x i ，y i ，z i ) The time course vibration results may include information such as vertical vibration displacement, velocity, and acceleration. Of course, depending on the computational requirements and analysis software, the defined vibration result file types may also be different.
And generating finite element grids consistent with the evaluation point grid set of the vibration analysis model on the acoustic radiation calculation model by using the node numbers and the coordinate positions when the vibration result file of the evaluation point grid set is compiled for the second time aiming at the vibration result file, and enabling the time-course vibration result on each unit node to be in one-to-one correspondence with the finite element grids of the acoustic radiation calculation model. Therefore, the transplanting of the grid set vibration result from the finite element vibration analysis software to the noise analysis software can be realized, and the method is applicable to most vibration and noise analysis software at present. In order to facilitate the realization of the process, a vibration-noise data interface can be specially developed, and the vibration result file of the evaluation point grid set is compiled for the second time, wherein the vibration-noise data interface can be developed through Matlab programming.
And generating a finite element grid consistent with the vibration analysis model evaluation point grid set in noise analysis software after secondary compiling, namely the structural grid in fig. 2, and corresponding a vibration result to the structural grid. In order to facilitate the calculation of frequency domain vibration acoustic radiation, it is preferable that the time-frequency conversion of the vibration response is completed by performing fourier transform on the time-course vibration result to generate a frequency domain vibration result, and then the frequency domain vibration result is mapped onto a finite element grid of the acoustic radiation calculation model. Then regenerating an acoustic calculation domain grid based on the adaptive order finite element technology, namely the acoustic grid in fig. 2, and mapping the frequency domain vibration result onto the surface of the acoustic calculation domain grid; generating a field point grid for outputting a noise calculation result; and (4) rapidly calculating the secondary structural noise in the frequency domain by applying an adaptive order finite element technology. After the calculation is completed, the noise analysis software can read and derive a plurality of noise result forms such as a frequency spectrum, an equivalent A sound level, a sound pressure distribution cloud chart and the like of the noise characteristic of the evaluation point, wherein the noise characteristic comprises but is not limited to sound pressure, sound pressure level, sound power and sound power level.
Examples
The present invention is illustrated with a four-story brick-concrete building along a railway as an example.
The four-layer brick-concrete structure building, the site situation and the model schematic and main parameters are shown in fig. 5 and table 1. Calculating the train induced vibration response by adopting a time domain analysis method, wherein the running speed of the train is 80km/h, the passing time is 8s, and the calculated time step is set to be 0.002s; and solving the acoustic response of the vibration result in a frequency domain after FFT, wherein the analysis bandwidth and the frequency resolution are respectively 250 Hz and 0.125Hz.
Table 1 example soil parameters
To illustrate the advantages of FEMAO techniques for solving for the presence of secondary structure noise, the computational efficiency pairs of conventional FEM and FEMAO techniques are shown in table 2.
TABLE 2 comparison of FEM and FEMAO computational efficiency
As can be seen from table 2, the FEMAO method is used to calculate the secondary structure noise, and the acoustic response with higher frequency can be accurately calculated by using a smaller number of acoustic finite element mesh models; meanwhile, under the condition that the hardware conditions of the computers are consistent, the FEMAO method occupies lower memory during calculation, and the solving time can be saved by 3 times. The FEMAO technology has great advantages in reducing the number of grids and the calculation cost.
The test and simulation results for vertical vibration at a floor of a building along a railway are shown in fig. 6.
As can be obtained from FIG. 5, the test and simulation results are basically consistent within the frequency range of 10-63 Hz with obvious vibration response, the simulation result of the vertical maximum frequency division vibration level of the floor slab is 75.4dB, and the test result is 74.4dB; the difference of the results is mainly reflected in a high-frequency region above 100Hz, and the building vibration level is low in the range, so that the whole vibration level is not influenced. A large number of research results also show that the vehicle-induced vibration of the building is dominated by low-frequency vibration of 40-63 Hz, so that the simulation model can be considered to basically reflect the actual condition of the vehicle-induced vibration of the building.
As shown in FIG. 6, the comparison of the secondary structure noise result obtained by calculation by the method of the present application with the published result shows that the primary frequency of the secondary structure noise is concentrated in the range of 40-63 Hz, and the maximum sound pressure level is about 60-70 dB; the sound pressure level distribution range in other frequency bands is 20-50 dB, and the equivalent A sound level is about 40 dBA. The noise main frequency of the example is 63Hz, the peak value is 60.1dB, and the equivalent A sound level is 41dBA; the spectral curves are also substantially identical to the references. The results show that the calculation method can basically reflect the vehicle-induced vibration and the secondary structure noise level of the building along the line under the action of the train load, and has higher calculation efficiency compared with the traditional time domain finite element method.
Claims (4)
1. The method for rapidly calculating the secondary structural noise of the vibration caused by the rail transit vehicle is characterized by comprising the following steps of:
in the vibration analysis model, the whole building finite element model is discretized into a plurality of grid groups, the grid groups needing to evaluate the secondary structural noise are defined as evaluation point grid groups, the types of results needing to be output by the evaluation point grid groups are defined, and vibration result files of the evaluation point grid groups are calculated and output;
transplanting the vibration result of the evaluation point grid group to an acoustic radiation calculation model, and calculating secondary structural noise in a frequency domain;
after the vibration result file of the evaluation point grid set is output, the vibration result file of the evaluation point grid set is compiled for the second time, so that the vibration result file of the evaluation point grid set is re-integrated, and the vibration result of the evaluation point grid set is conveniently transplanted to an acoustic radiation calculation model;
the vibration result file of the evaluation point grid group comprises node numbers and coordinate positions of each unit node in the evaluation point grid group and time-course vibration results on each unit node;
when the vibration result file of the evaluation point grid set is compiled for the second time, generating finite element grids consistent with the evaluation point grid set of the vibration analysis model on the acoustic radiation calculation model by using the node numbers and the coordinate positions, and enabling the time-course vibration result on each unit node to correspond to the finite element grids of the acoustic radiation calculation model one by one;
firstly, performing Fourier transformation on a time-course vibration result to complete time-frequency conversion of vibration response to generate a frequency domain vibration result, and then, corresponding the frequency domain vibration result to a finite element grid of an acoustic radiation calculation model;
generating an acoustic calculation domain grid when the secondary structure noise is calculated, and mapping a frequency domain vibration result onto the surface of the acoustic calculation domain grid;
generating a field point grid for outputting a noise calculation result;
and (4) rapidly calculating the secondary structural noise in the frequency domain by applying an adaptive order finite element technology.
2. The method for rapidly calculating the secondary structural noise of the vibration of the rail transit vehicle as claimed in claim 1, wherein: and (3) developing a vibration-noise data interface, and performing secondary compiling on a vibration result file of the evaluation point grid set.
3. The method for rapidly calculating the secondary structural noise of the vibration of the rail transit vehicle as claimed in claim 1, wherein: the time course vibration results include vertical vibration displacement, velocity, and acceleration.
4. The method for rapidly calculating the secondary structural noise of the vibration of the rail transit vehicle as claimed in claim 1, wherein: after the secondary structure noise is calculated, the noise result of the derived evaluation point comprises a frequency spectrum, an equivalent A sound level and a sound pressure distribution cloud picture of noise characteristics, wherein the noise characteristics comprise sound pressure, sound pressure level, sound power and sound power level.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210147751.0A CN114519286B (en) | 2022-02-17 | 2022-02-17 | Method for rapidly calculating secondary structural noise of vibration caused by rail transit vehicle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210147751.0A CN114519286B (en) | 2022-02-17 | 2022-02-17 | Method for rapidly calculating secondary structural noise of vibration caused by rail transit vehicle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114519286A CN114519286A (en) | 2022-05-20 |
| CN114519286B true CN114519286B (en) | 2023-04-25 |
Family
ID=81600060
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210147751.0A Active CN114519286B (en) | 2022-02-17 | 2022-02-17 | Method for rapidly calculating secondary structural noise of vibration caused by rail transit vehicle |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114519286B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115828358B (en) * | 2022-09-14 | 2024-03-26 | 中国铁路设计集团有限公司 | Vehicle section upper cover building vibration reduction design method based on secondary structure noise control |
| CN116295804B (en) * | 2023-02-16 | 2023-11-03 | 中铁四院集团南宁勘察设计院有限公司 | Method for constructing vibration map |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102880767A (en) * | 2012-10-19 | 2013-01-16 | 西南交通大学 | Method for predicating noise simulation of rail transit bridge structure |
| CN104036087A (en) * | 2014-06-24 | 2014-09-10 | 同济大学 | Power flow-boundary element model based elevated rail traffic vibratory-noise simulating and predicting method |
| CN104715138A (en) * | 2015-01-28 | 2015-06-17 | 西南交通大学 | Rail fastener counter-force computing method and subway vibration frequency domain response computing method |
| WO2017121044A1 (en) * | 2016-01-11 | 2017-07-20 | 北京城建设计发展集团股份有限公司 | Precast slab railway track structural system for vibration mitigation and associated construction method |
| CN112550180A (en) * | 2020-11-27 | 2021-03-26 | 上海工程技术大学 | Noise-reduction interior trim system for special vehicle cab |
-
2022
- 2022-02-17 CN CN202210147751.0A patent/CN114519286B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102880767A (en) * | 2012-10-19 | 2013-01-16 | 西南交通大学 | Method for predicating noise simulation of rail transit bridge structure |
| CN104036087A (en) * | 2014-06-24 | 2014-09-10 | 同济大学 | Power flow-boundary element model based elevated rail traffic vibratory-noise simulating and predicting method |
| CN104715138A (en) * | 2015-01-28 | 2015-06-17 | 西南交通大学 | Rail fastener counter-force computing method and subway vibration frequency domain response computing method |
| WO2017121044A1 (en) * | 2016-01-11 | 2017-07-20 | 北京城建设计发展集团股份有限公司 | Precast slab railway track structural system for vibration mitigation and associated construction method |
| CN112550180A (en) * | 2020-11-27 | 2021-03-26 | 上海工程技术大学 | Noise-reduction interior trim system for special vehicle cab |
Non-Patent Citations (2)
| Title |
|---|
| 张晓喜 等.220 kV变压器引起的结构振动与二次噪声研究.《噪声与振动控制》.2020,第40卷(第03期),第188-193页. * |
| 毛东兴 等.城市轨道交通浮置式减振措施的减振降噪效果.《环境工程》.2012,第30卷(第S1期),第47-52页. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114519286A (en) | 2022-05-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114519286B (en) | Method for rapidly calculating secondary structural noise of vibration caused by rail transit vehicle | |
| Hornikx | Ten questions concerning computational urban acoustics | |
| CN104765906B (en) | A kind of tire outline acoustics Contribution Analysis method | |
| CN111159938B (en) | Underwater vibration noise prediction method for river-crossing tunnel of road | |
| CN108009344B (en) | Train far-field pneumatic noise prediction method and device and train | |
| CN104102838A (en) | Transformer noise prediction method based on wavelet neural network and wavelet technology | |
| CN111310316A (en) | Vehicle model selection method based on high-precision simulation of far-field noise of high-speed train | |
| CN116090526A (en) | Structural vibration noise inversion method based on embedded physical information neural network | |
| Waezi et al. | Stochastic non-stationary model for ground motion simulation based on higher-order crossing of linear time variant systems | |
| JP2022066143A (en) | Simulation test system and method for cancellation of noise from vehicle road | |
| JP2023112664A (en) | Representing full-scale wind turbine noise | |
| US20140340406A1 (en) | Acoustic performance calculation device, acoustic performance calculation method, and acoustic performance calculation program | |
| CN104951798A (en) | Method for predicting non-stationary fluctuating wind speeds by aid of LSSVM (least square support vector machine) on basis of EMD (empirical mode decomposition) | |
| CN108763646A (en) | Box beam local vibration prediction technique based on FE-SEA mixing methods | |
| Morales et al. | Efficient wave-based acoustic material design optimization | |
| CN106844971B (en) | Rail transit bridge noise inversion prediction method based on inverse boundary element | |
| CN110502844A (en) | A kind of optimum design method of rail traffic vehicles noisy digit model machine | |
| CN111382533A (en) | Simulation analysis method for electromagnetic vibration noise of transformer | |
| JP7488952B2 (en) | Methods for reducing vehicle pass-by noise | |
| CN113312759A (en) | Method and system for calculating noise source intensity of converter transformer bank | |
| Azad et al. | A study of diffusivity in concert halls using large scale acoustic wave-based modeling and simulation | |
| Van Haaren et al. | Validation of ray acoustics applied for the modelling of noise barriers | |
| Adams et al. | Sound quality equivalent modeling for virtual car sound synthesis | |
| CN115828358B (en) | Vehicle section upper cover building vibration reduction design method based on secondary structure noise control | |
| CN113536647B (en) | Full-band-based optimization method for automobile damping fin based on air sound and structure sound analysis |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |