Study On The Relationship Between Internal Noise And Sound Insulation Of High Speed Train Components

With the rapid development of technology and economy,the noise in high-speed train becomes the focus of people’s attention.The acoustic environment in the vehicle directly affects the comfort of passengers.Therefore,it is an important optimization direction to control the noise in the train.In order to get a quiet acoustic environment in the vehicle,the sound insulation performance of components on the main noise transmission path is usually strengthened to weaken the transmission of noise.This paper studies and analyzes the propagation path of the noise in the high-speed train,and then analyzes the influence of sound insulation performance of each component on the noise in the vehicle.Based on python,the calculation of the sound insulation performance of the VA-One vehicle body composite structure is developed twice,and some parts of the structure are optimized.The main contents are as follows:1.According to the structural parameters of the high-speed train body,the prediction model of the interior noise of the first vehicle and the middle vehicle is established based on the statistical energy analysis method,and the sound insulation performance curves of the aerodynamic,wheel rail noise sources and key components are applied.According to GB/T3449-2011 acoustics-Measurement of interior noise of rail vehicles,the noise monitoring points are selected in the vehicle,and the interior noise is simulated,The noise spectrum in the frequency range of 100 ～ 4000 Hz is obtained,and the sound pressure level of each monitoring point in the vehicle is analyzed.The results show that the sound pressure level of the cab of the first vehicle and the rear of the middle vehicle is higher.2.The power flow spectrum of the cab of the first vehicle and the rear of the middle vehicle with higher sound pressure level is analyzed,the main noise transmission path and key sound transmission components are determined,and the influence of sound insulation performance of floor,side window,side wall and roof on the internal noise of high-speed train is analyzed.The results show that the sound insulation performance of the roof has little influence on the sound pressure level inside the vehicle,while the sound insulation performance of the floor,side window and side wall has a greater influence.The floor has the greatest influence on the noise inside the vehicle,and the main influence position is the cab of the first vehicle and the front part of the middle vehicle.The main influence frequency range is 100 ～ 200 Hz and 1000 ～ 4000 Hz.3.In order to improve the efficiency of simulation calculation of component sound insulation,the secondary development of VA-One based on Python is carried out,and the calculation program of composite structure sound insulation is compiled,which simplifies the calculation process.The sound insulation simulation models of vehicle floor and side window components are established,and the influence of structure size and material property parameters on sound insulation performance is analyzed and compared by secondary development program.The results show that laying 10 mm hard rubber on the floor can improve the sound insulation performance,and the weighted sound insulation of the floor is increased by about 6d B;The scheme of filling helium in the air layer of the side window has a good effect,and the weighted sound insulation is improved by about 17.5d B.The research results of this paper can provide reference for the simulation of interior noise,noise control and optimization of sound insulation performance of components of high-speed trains,and have certain engineering application value.