城市轨道交通近轨吸声矮墙降噪量数值仿真分析

Numerical Simulation Analysis of Noise Reduction for Urban Rail Transit Low-height Trackside Soundproof Wall

为解决城市轨道交通带来的噪声问题和弥补传统声屏障的不足之处,结合国外相关经验和国内规范设计了一款近轨吸声矮墙。为进一步验证这款产品的降噪量,借助Virtual.Lab平台,引用现有文献中关于我国城市轨道交通的噪声源强参数,用声学间接边界元法计算不同顶部形式近轨吸声矮墙在不同受声点处的降噪能力。结果表明:近轨吸声矮墙对于较低区域的受声点,比如行人,保护效果更好;不同顶部结构的近轨吸声矮墙,其降噪峰值、峰值频率以及频率特性均有所不同,可利用该特性选择不同顶部形式增强其降噪频率的针对性,且各类顶部形式的降噪量均能满足规范要求;仿真结果与经验公式计算结果对比发现,在相对较高的频段,其结果较为可靠。

In order to solve the noise problems caused by urban rail traffic and make up for the shortcomings of the traditional sound barrier,a low-height trackside soundproof wall has been designed in the light of relevant foreign experience and domestic standards.In order to further verify the noise reduction of this product,the noise reduction capability of different top low-height trackside soundproof wall at different sound-receiving points is calculated by using the acoustic indirect boundary element method with the help of the Virtual.Lab platform and the existing literature about the noise source intensity parameters of urban rail transit in China.The results show that the track edge sound-absorbing dwarf wall has better protection effect for the lower region,such as the pedestrian.The noise reduction peak,the peak frequency and the frequency characteristics of the low-height trackside soundproof wall with different top structures are different,this feature can be used to select different top forms to enhance the frequency of noise reduction,and the noise reduction of all kinds of top forms can be full of standard requirements;the simulation results and the experience public are good.Comparison of the results shows that the results are reliable at relatively high frequency bands.