Radiated sound‐pressure levels and sound source locations on the German ICE high‐speed train

1988 ◽  
Vol 84 (S1) ◽  
pp. S119-S119
Author(s):  
E. Pfizenmaier ◽  
W. F. King ◽  
H. Lettmann ◽  
B. Barsikow
Keyword(s):  
Sound Source ◽  
High Speed ◽  
Sound Pressure ◽  
High Speed Train ◽  
Sound Pressure Levels ◽  
Radiated Sound

scholarly journals An investigation into high-speed train interior noise with operational transfer path analysis method

2021 ◽  
Author(s):  
Muxiao Li ◽  
Ziwei Zhu ◽  
Tiesong Deng ◽  
Xiaozhen Sheng
Keyword(s):  
Sound Source ◽  
Reference Point ◽  
Source Identification ◽  
High Speed ◽  
Interior Noise ◽  
Target Point ◽  
High Speed Train ◽  
Transfer Path ◽  
Sound Source Identification ◽  
Transfer Path Analysis

AbstractPassengers' demands for riding comfort have been getting higher and higher as the high-speed railway develops. Scientific methods to analyze the interior noise of the high-speed train are needed and the operational transfer path analysis (OTPA) method provides a theoretical basis and guidance for the noise control of the train and overcomes the shortcomings of the traditional method, which has high test efficiency and can be carried out during the working state of the targeted machine. The OTPA model is established from the aspects of "path reference point-target point" and "sound source reference point-target point". As for the mechanism of the noise transmission path, an assumption is made that the direct sound propagation is ignored, and the symmetric sound source and the symmetric path are merged. Using the operational test data and the OTPA method, combined with the results of spherical array sound source identification, the path contribution and sound source contribution of the interior noise are analyzed, respectively, from aspects of the total value and spectrum. The results show that the OTPA conforms to the calculation results of the spherical array sound source identification. At low speed, the contribution of the floor path and the contribution of the bogie sources are dominant. When the speed is greater than 300 km/h, the contribution of the roof path is dominant. Moreover, for the carriage with a pantograph, the lifted pantograph is an obvious source. The noise from the exterior sources of the train transfer into the interior mainly through the form of structural excitation, and the contribution of air excitation is non-significant. Certain analyses of train parts provide guides for the interior noise control.

Effect of Pantograph and Bogie on Interior Noise of High-Speed Train in Tunnel

2013 ◽  
Vol 664 ◽  
pp. 191-196
Author(s):  
You Gang Xiao ◽  
Yu Shi
Keyword(s):  
High Speed ◽  
Sound Pressure ◽  
Broad Band ◽  
Pressure Level ◽  
Channel Noise ◽  
High Speed Train ◽  
Noise Sources ◽  
Vehicle Noise ◽  
Measurement And Analysis ◽  
Analysis System

For clarifying the noise in tunnel affected by pantograph and bogie, which are the most important noise sources, the noises near pantograph and bogie in a high-speed train were tested by multi-channel noise measurement and analysis system in tunnel, and compared with those measured outside the High-speed train and on an open field. The results show that the interior vehicle noise is spatially non-homogeneous in the whole carriage, the larger sound pressure level (SPL) near pantograph are next to ceiling, and near bogie next to floor. The noise spectra show a broad band feature, and dominated by the frequency contents among 100Hz-2kHz, so the countermeasures against noise should be within these range.

Shape Optimization of High-Speed Train Pantograph Insulators for Low Aerodynamic Noise

2012 ◽  
Vol 249-250 ◽  
pp. 646-651
Author(s):  
Xiao Yan Yang ◽  
You Gang Xiao ◽  
Yu Shi
Keyword(s):  
Shape Optimization ◽  
Sound Pressure Level ◽  
High Speed ◽  
Sound Pressure ◽  
Pressure Level ◽  
Aerodynamic Noise ◽  
High Speed Train ◽  
Eddy Simulation ◽  
Large Eddy ◽  
Elliptical Section

With large eddy simulation(LES) and Lighthill-Curle acoustic theory, the aerodynamic noises radiated from pantograph insulators with rectangular, circular, elliptical section were calculated, and the optimal pantograph insulator shape was obtained. The results show that in the same model, the sound pressure level (SPL) spectrum at different monitoring points are basically the same, but the amplitude is different. In different models, the SPL spectrum are different. As for rectangular, circular, elliptical section insulators, the frequency with maximum SPL reduces gradually. For reducing aerodynamic noise, the elliptical section insulator is optimal, and the long elliptical axis should be consistent with air flow. The pantograph with bigger and less components is helpful to reduce the aerodynamic noise.

scholarly journals A Systematic Approach to Identify Sources of Abnormal Interior Noise for a High-Speed Train

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Jie Zhang ◽  
Xinbiao Xiao ◽  
Xiaozhen Sheng ◽  
Zhihui Li ◽  
Xuesong Jin
Keyword(s):  
High Speed ◽  
Sound Pressure ◽  
Systematic Approach ◽  
Noise Analysis ◽  
Interior Noise ◽  
Sound Insulation ◽  
High Speed Train ◽  
Main Contributor ◽  
Vibration Data ◽  
High Speed Trains

A systematic approach to identify sources of abnormal interior noise occurring in a high-speed train is presented and applied in this paper to resolve a particular noise issue. This approach is developed based on a number of previous dealings with similar noise problems. The particular noise issue occurs in a Chinese high-speed train. It is measured that there is a difference of 7 dB(A) in overall Sound Pressure Level (SPL) between two nominally identical VIP cabins at 250 km/h. The systematic approach is applied to identify the root cause of the 7 dB(A) difference. Well planned measurements are performed in both the VIP cabins. Sound pressure contributions, either in terms of frequency band or in terms of facing area, are analyzed. Order analysis is also carried out. Based on these analyses, it is found that the problematic frequency is the sleeper passing frequency of the train, and an area on the roof contributes the most. In order to determine what causes that area to be the main contributor without disassembling the structure of the roof, measured noise and vibration data for different train speeds are further analyzed. It is then reasoned that roof is the main contributor caused by sound pressure behind the panel. Up to this point, panels of the roof are removed, revealing that a hole of 300 cm2 for running cables is presented behind the red area without proper sound insulation. This study can provide a basis for abnormal interior noise analysis and control of high-speed trains.

Analysis of the Influence of Racks on High Speed Train Interior Noise Using Finite Element Method

2014 ◽  
Vol 675-677 ◽  
pp. 257-260 ◽  
Author(s):  
Di Wu ◽  
Jian Min Ge
Keyword(s):  
Finite Element ◽  
Sound Pressure Level ◽  
High Speed ◽  
Sound Pressure ◽  
Low Frequency ◽  
Sound Field ◽  
Pressure Level ◽  
High Speed Train ◽  
Fe Method ◽  
Proposed Model

In this paper, the finite element (FE) method was used for simulation of the low-frequency sound field in high speed train compartments. The proposed model was validated using experimental results. The FE models of the train compartments with and without racks were established respectively, and the sound pressure level of the standard point and sound field distribution in these two cases were compared. The results showed that the A-weighted sound pressure level of the standard point was 1.2 dB lower when there is no rack in the compartment.

scholarly journals Aerodynamic noise radiating from the inter-coach windshield region of a high-speed train

2018 ◽  
Vol 37 (3) ◽  
pp. 590-610 ◽  
Author(s):  
Wen-Qiang Dai ◽  
Xu Zheng ◽  
Zhi-Yong Hao ◽  
Yi Qiu ◽  
Heng Li ◽  
...  
Keyword(s):  
Sound Pressure Level ◽  
High Speed ◽  
Sound Pressure ◽  
Near Field ◽  
Acoustic Power ◽  
Pressure Level ◽  
Aerodynamic Noise ◽  
Dominant Factor ◽  
High Speed Train ◽  
Frequency Range

The aerodynamic noise has been the dominant factor of noise issues in high-speed train as the traveling speed increases. The inter-coach windshield region is considered as one of the main aerodynamic noise sources; however, the corresponding characteristics have not been well investigated. In this paper, a hybrid method is adopted to study the aerodynamic noise around the windshield region. The effectiveness of simulation methods is validated by a simple case of cavity noise. After that, the Reynolds-averaged Navier–Stokes simulation is used to obtain the characteristics of flow field around the windshield region, which determine the aerodynamic noise. Then the nonlinear acoustic solver approach is employed to acquire the near-field noise, while the Ffowcs-Williams/Hawking equation is solved for far-field acoustic propagation. The results indicate that the windshield region is approximately an open cavity filled with severe disturbance flow. According to the analysis of sound pressure distribution in the near-acoustic field, both sides of the windshield region appear symmetrical two-lobe shape with different directivities. The results of frequency spectrum analysis indicate that the aerodynamic noise inside inter-coach space is a typical broadband one from 100 Hz to 5k Hz, and most acoustic power is restricted in the low-medium frequency range (below 500 Hz). In addition, the acoustic power in the low frequency range (below 100 Hz) is closely related to the cavity resonance with the resonance peak frequency of 42 Hz. The overall sound pressure level at different speeds shows that the acoustic power grows approximately 5th power of the train speed. Two forms of outside-windshields are designed to reduce the noise around the windshield region, and the results show the full-windshield form is better in noise reduction, which apparently eliminates interior cavity noise of inter-coach space and lessens the overall sound pressure level on the sides of near-field by about 13 dB.

Noise-source identification of a high-speed train by noise source level analysis

2016 ◽  
Vol 231 (6) ◽  
pp. 717-728 ◽  
Author(s):  
Hee-Min Noh
Keyword(s):  
Source Identification ◽  
High Speed ◽  
Sound Pressure ◽  
Noise Source ◽  
Microphone Array ◽  
Beam Power ◽  
High Speed Train ◽  
Scaling Factors ◽  
Noise Source Identification ◽  
Level Analysis

In this study, noise-source identification of a high-speed train was conducted using a microphone array system. The actual sound pressure level analysis of the noise source was performed using scaling factors between the real sound pressure and the beam-power output based on the assumption that the integrated area of the main beam-power lobe is equal to half that of the actual sound pressure of the noise source. Then, the scaling factors for the 144-channel microphone array were derived from analysis of the array response function, and a verification experiment was conducted using a known noise source, an air horn, located on a high-speed train moving at 240 km/h. After the verification test, noise-source identification of the high-speed train was conducted. Based on the resulting noise map of the high-speed train moving at 390 km/h, the main noise sources were determined to be the inter-coach spacing, wheels, and pantograph. The noise generated by the pantograph was then investigated in more detail. It was concluded that the pan head of the pantograph was the main noise source at a frequency of 1000 Hz.

scholarly journals Numerical simulation of the slipstream and aeroacoustic field around a high-speed train

2016 ◽  
Vol 231 (6) ◽  
pp. 740-756 ◽  
Author(s):  
Chunli Zhu ◽  
Hassan Hemida ◽  
Dominic Flynn ◽  
Chris Baker ◽  
Xifeng Liang ◽  
...  
Keyword(s):  
Sound Pressure Level ◽  
High Speed ◽  
Sound Pressure ◽  
Low Frequency ◽  
Pressure Level ◽  
Broadband Noise ◽  
Full Scale ◽  
High Speed Train ◽  
Noise Characteristics ◽  
Simulation Results

The flow field and sound propagation around a three-coach 1/8th scale high-speed passenger train were obtained using a detached-eddy simulation and the Ffowcs-Williams and Hawkings acoustic analogy. The Reynolds number of flow based on the train height and speed was 2,000,000. The numerical results of the flow and aeroacoustic fields were validated using wind tunnel experiments and full-scale data, respectively. Features of overall sound pressure level, sound pressure level and A-weighted sound pressure level of typical measuring points are discussed. The sound propagated by a high-speed train is shown as a broadband noise spectrum including tonal component, where high sound pressure levels are concentrated on the low-frequency range from 10 Hz to 300 Hz. The inter-carriage gap is found to cause distinct tonal noise in contrast to the other parts of the train that cause a broadband noise. The negative log law has been used to study the influence of distance from the centre of track on the sound pressure level, where a good fit is shown at low-frequency ranges. The peak values of A-weighted sound pressure level from both full-scale experiment and simulation results occur at approximately 1 kHz, where simulation results show almost the same range as the experiment. The surface of each component of the train as well as the whole train are chosen as the integral surface for the Ffowcs-Williams and Hawkings computation of the far-field noise characteristics. It was found that the sound source generated by a high-speed train is mainly dipole, and the largest noise was obtained from the leading bogie. The results of this paper provide, for the first time, a better understanding of the aeroacoustic field around a three-coach train model, and the paper has the potential to assist engineers to design high-speed trains with aeroacoustic noise reduction in a better manner.

Sign in / Sign up

Export Citation Format

Share Document