Research On Acoustic Characteristics Of Sound Absorbing Materials And Sound Insulation Components Of High Speed Passenger Train

With the continuous development of high speed railway technology,the speed of train is getting higher and higher,the noise problem is more obvious,the noise is one of the important indicators of train performance evaluation.Today,Sound-absorbing materials and sound insulation components are increasingly used in high speed passenger train.Therefore,the study of sound-absorbing materials and sound insulation components has a very important significance.In this paper,the sound absorption performance of different materials is tested by reverberation chamber method and impedance tube method.The relationship between the two test results is compared.The effects of different layout and different specimen area and thickness on the test results of sound absorption characteristics are studied.The sound insulation characteristics of different components are tested by sound insulation chamber method,The sound insulation of components is simulated and the two results is compared.The following conclusions are drawn from the study: The law of sound absorption coefficient of materials measured by reverberation chamber method varies with the area of specimen is the sound absorption coefficient increases with the area decreases,The test piece with the area of 9 ? and the standard area has the similar sound absorption coefficient results.The sound absorption coefficient of the material measured by the reverberation chamber method and the impedance tube method is different in numerical value,but the center frequency of the peak of the sound absorption coefficient is basically the same,which can meet the different test requirements and practical application.The overall trend of the sound insulation curve of the aluminum components measured in sound insulation chamber is the sound insulation increases with frequency increasing,Increasing the thickness of the air layer can increase the overall sound insulation of the components.The results show that there is a difference between the simulation value and the experimental test results in the 100Hz~200Hz frequency range,which is basically the same in 250Hz~5000Hz frequency range.The use of fasteners in sound insulation tests helps to install and seal the test pieces,but it has little effect on the test results,The sealing degree on both sides of the specimen has a great influence on the low and medium frequency of Sound insulation,The test piece can be fixed with a certain number of fasteners and sealed on both sides of the specimen using a sealant.The conclusion of this paper is of great reference meaning and application value for sound absorbing materials and sound insulation components of high speed passenger train.