Research On The Interior Noise Source Identification Of High-speed Train By Sound Intensity Method

With the increasing speed of the train operator.the train interior noise impact on passengers ride comfort is also growing, which makes the interior noise problem becomes more important and urgent. The ability to correctly identify the main sources of noise inside the train car is the key to solve the noise problem.Therefore, to develop a set of easy to use and inexpensive noise source identification system has important meaning.Firstly, the high-speed train interior noise characteristics, noise source identification technology and sound intensity measurement theories were analyzed and summarized, by comparing the advantages and disadvantages of existing noise source identification technology at home and abroad, finally determine the sound intensity method is adopted for high-speed train interior noise source identification.Then, achieved the development and design of the hardware and software systems of sound intensity measurement and analysis system. First of all, completed the development of hardware system, which consists of two microphone, data acquisition card, signal conditioning and PC machines, etc.; Then, based on the labview virtual instrument development platform to develop the corresponding software system, which can realize data acquisition, data read and storage, system calibration, spectral analysis and the sound intensity calculation,1/3octave analysis, draw three-dimensional map of sound intensity and isacousticchart and other functions.Subsequently, on the basis of interior noise in circuit test data, and conducted verification test in the generalized comfort simulation experiment platform, adopted the sound intensity measurement analysis system to identify the main noise source in the train car, the main noise source location which identified by the three-dimensional map of sound intensity and isacousticchart is consistent with the actual position, and the result is good. Thus we can conclude that the system can be drawn to meet the general accuracy of the noise source identification requirements.Finally, this paper analyzes the development of sound intensity measurement system for line test data were analyzed, the main source for the car and the car’s typical sound intensity measuring point frequency characteristics were analyzed and summarized.Finally, adopted in the sound intensity measurement analysis system to analyzed the circuit test data, and summarized the main sound source inside the car and the car typical sound intensity measuring point frequency characteristic.