Prediction And Control Of Interior Low Frequency Aerodynamic Noise Of High-Speed Train

With the speed of the train increasing continuously, the train’s vibration is more and more intense under the aerodynamic loads, the interior noise of the high-speed train increasing gradually, which leads to reducing the comfort of passengers greatly. This article will predict and analysis the interior low frequency aerodynamic noise(including the ground, the intersection of the two high-speed trains, passing through the tunnel etc.) of high-speed train, for further control of interior noise analysis for bedding.The main content of studying includes the following aspects in this paper:1. The aerodynamic model of the high-speed train was built. With the computational software FLUENT, The fluctuation pressures of the train’s surface under the ground, the intersection of the two high-speed trains and passing through the tunnel were obtained by using the LES. The result shows that under the same conditions, as the speed of the train increasing, the fluctuation pressure of the middle train’s surface is larger. And when the speeds of high-speed train are same, the fluctuation pressures of the middle train’s surface is the largest as passing through tunnel.2. The structure finite element model of the middle of the high-speed train was built. With the finite analysis software ANSYS, which was conducted modal analysis, and the vibration displacements under the ground, the intersection of the two high-speed trains and passing through the tunnel are obtained through the transient analysis. The result shows that the vibration displacements of the roof, the windows are largest, the floor is followed by and the end wall is smallest under only the aerodynamic loads. With the speed of the high-speed train improving, the train’s vibration is more and more intense. And when the speeds of high-speed train are same under all condtions. the vibration displacement of the train passing through tunnel is largest, especially at the time of the train entering the tunnel.3. The acoustic model of the high-speed passenger cabin was built. With the acoustic software Virtual.Lab Acoustic, the distribution of the interior noise under the different conditions were analysised in detail by using the direct boundary element method. The result shows that:interior low frequency aerodynamic noise increases with the speed of the square. The sound pressure of observation plane from the bottom of the train height of1.2m is larger than the height of1.6m. And when the speeds of high-speed train are same under all condtions, the sound pressure of the train passing through tunnel is largest, the intersection of the two high-speed trains is followed by, the sound pressure of the train which run on the ground is smallest.4. Based on the acoustic transfer vector method, the contribution of the train plate was analysised. The result shows that the contributions of the roof, the floor and the windows are largest, and the end wall is smallest. Based on the above-mentioned analysis of the contribution of the plates of which are some larger, and define the sound absorption properties and increase the train body stiffness, which can be effective in reducing interior noise, and improving the comfort of the passengers.