跨座式单轨交通车外噪声源识别试验研究

Experimental Study on External Noise Sources Identification of Straddle-type Monorail Transit

为掌握跨座式单轨交通车外噪声源的组成和辐射特性,基于单轨交通线路和车辆结构特点,运用时频波束形成噪声源识别方法,对运行列车底部和侧面辐射噪声展开试验研究。结果表明:运行列车车外辐射噪声主要位于车厢最底部裙板与轨道梁接触区域附近,500 Hz以上的噪声源主要由胎轨噪声和弓网噪声构成。胎轨噪声为周期性的冲击噪声,主要辐射频段800~2 000 Hz,峰值频率为1 250 Hz,较集中分布于车厢最底部裙板两侧;而弓网噪声具有不连续冲击特性,主要辐射频段为3 500~7 500 Hz,沿接触网方向呈线状离散分布在弓网接触区域。此外,弓网噪声的声压级要低于胎轨噪声,但弓网噪声属于人耳较敏感的高频噪声,对列车运行声品质影响较大,其降噪控制应给予重视。

In order to understand the composition and radiation characteristics of external noise sources of straddle-type monorail vehicles,the time-frequency beamforming noise source identification method is used to conduct experimental research on the bottom and side radiated noise of running train based on the characteristics of monorail transport lines and vehicle structures.The results show that the radiated noise from the running train is mainly located near the contact area between the bottom skirt of the carriage and the track beam,and the noise sources above 500 Hz are mainly composed of tire-rail noise and pantograph-catenary noise.Tire-rail noise,a periodic impact noise,is concentrated on both sides of the bottom skirt of the carriage,of which,the main radiation frequency band is about 800~2000 Hz and the peak frequency is 1250 Hz;while the pantograph-catenary noise mainly radiates at 3500~7500 Hz,which is distributed in the contact area of pantograph and catenary along the catenary direction in a linear and discrete distribution.In addition,the sound pressure level of the pantograph-catenary noise is lower than that of the tire-rail noise,but the pantograph-catenary noise belongs to high-frequency noise that is sensitive to human ear and has a great impact on the sound quality of train operation.So,more attention should be paid to its noise reduction control.