100%低地板列车车内声源识别试验研究

Experimental Study on Interior Noise Source Identification for 100% Low-floor Railway Trains

100%低地板列车是一种新型绿色环保的城市区域交通运输车辆。针对其特殊的车体结构,提出了更高的车内噪声控制要求。通过线路噪声试验,和100%低地板列车车内声源特性的系统测试,定性分析了车内显著声源的传递路径,在此基础上提出车内减振降噪建议措施。试验结果表明,100%低地板列车车内各个测点的声源能量主要集中在中心频率400 Hz^1 250 Hz的1/3倍频带,声源位置主要位于地板、顶板以及风挡区域。车内最显著频带声源的传递路径以空气传声为主。控制车辆外部空气声源,提高车体结构的密封、隔声性能是降低车内噪声的可行方法。研究结果可为100%低地板列车车内减振降噪提供参考。

The 100 % low-floor train is a new type of green urban railway transportation tools.However,control of interior noise is a more complicated issue due to its special car body＇s structure.In this paper,based on the field measurements,the characteristics of the interior noise source of the 100 % low-floor train are analyzed.Then,a qualitative analysis is done to identify the transmission path of the significant interior noise sources.On this basis,measures for reduction of interior noise and vibration are proposed.The results show that the sound source power of the interior noise is mainly concentrated on the 1/3 octave frequency band with the central frequency of 400 Hz -1 250 Hz.The interior noise sources are mainly located in the floor,roof,vestibule diaphragm,etc.And the air- borne sound is the key noise transfer mode.It is a feasible way to reduce the interior noise by controlling the external noise and improving the sealing and sound insulation of the car body.This work provides a basis for further finding the interior noise control measures for the 100 % low-floor railway train.