Sound Insulation Simulation&Acoustic Parameters Experiment Of High-speed EMU Body Plate

The car body lightening development and the speed increasing of the high speed passenger train, which makes the interior noise control becomes more and more difficulty, thus affecting the travelling comfort of the passengers. A large number of study show that the interior noise is mainly composed of the vibration noise under the train, aerodynamic noise on the surface and pantograph noise, which all of them could transmit into the car through the body. It is always show that the interior noise between100and1000Hz is bigger than other frequencies. Therefore the sound insulation performance of the body plate structure will directly affect the travelling environment.The main objective of the paper is to study the body sheet (ID:A1, A2, A3, B1, B2, B3, C1, C2, D1, D2) of the High-speed EMU. Firstly, a sound insulation measurement is processed, in order to get its insulation, which based on the reverberation room-semi anechoic chamber sound insulation test method. Secondly get the damping loss factor of each plate via free vibration test method, free vibration of the cantilever beam for getting the elastic modulus and admittance test method to get the modal density.On the basis of test data, using VA one, acoustic vibration full-frequency simulation software, establish static energy analysis model for panel B3and finite element model for others. Then put the experiment parameters into the material properties of the model. Lastly get the simulation results of the sound insulation, which based on Reverberation room test method.By comparing the sound insulation curves of each body plates, analysis the effects on the sound insulation of the hollow extruded aluminium floor by the different damping treatments.Comparing the simulation results with experiment results, it is proved that the simulation model is feasible and effectiveness in sound insulation simulation. In addition, the effect of sound coupling much larger than the air coupling within the frequency range of100～1000Hz,for extruded aluminium panels.