低地板车结构传声及车内噪声特性

对我国某100 %低地板车辆在60 km/h速度下进行振动噪声试验，获得了低地板车动车、拖车，车内及转向架噪声特性。结果表明，车内噪声主要能量集中在400 Hz～1250 Hz，其中400 Hz频谱能量最大。动车比拖车车内噪声高3 dB，这是由于转向架动力源激励400 Hz中心频段结构传声和空气传声所致。控制电机振动，能从源头上有效控制车内400 Hz中心频率结构传声。此外，也需要从路径上控制电机激励结构传声，即控制横向减振器和二系空簧的结构传声。相关分析结果可为低地板车振动噪声控制和低噪声设计提供参考。

Structure-borne Sound Transfer Path of a Low-floor Vehicle and Its Interior Noise Property

The in-situ vibration and noise test of a domestic 100 % low floor vehicle at the traveling speed of 60 km/h is carried out.The noise characteristics of the motor car,the trailer car and the bogie of the vehicle are obtained.The results show that the energy of the interior noise is mainly distributed in the frequency band of 400 Hz-1 250 Hz,in which the energy is the largest at about 400 Hz frequency.The interior noise of the motor car is at least 3 dB higher than that of the trailer car.This is mainly due to the bogie power＇s structure borne and air borne noises.Reduction of the motor＇s vibration is the best way to control the interior noise due to the structure borne with the central frequency of 400 Hz.In addition,it is necessary to control the transfer path of the structure borne due to the motor＇s excitation,i.e.control the sound borne by the lateral damper and the air damper.This study provides a reference for low-floor vehicle＇s noise and vibration control and noise reduction design.