虚拟轨道列车运行噪声特性及评价分析

Noise Characteristics and Evaluation Analysis of Virtual Track Trains

虚拟轨道列车正在我国得到快速发展,其车内外噪声水平、特性及形成机理还缺少相关研究。基于线路试验,对虚拟轨道列车开展声源识别和振动噪声测试,分析其车内外噪声水平、频谱特性和速度依赖关系,进而参考城市轨道交通列车和汽车相关噪声限值标准对车内外噪声进行评价分析,最后对其噪声形成机理和关键控制技术进行初步探讨。结果表明:其以52.5 km/h匀速运行时,车内外噪声分别为69.5 dB(A)和67.8 dB(A);相比城市轨道交通列车和汽车相关噪声限值,虚拟轨道列车车内噪声分别低于噪声限值5.5 dB(A)和14.5 dB(A);车外噪声低于城市轨道交通列车限值11.5 d B(A);虚拟轨道列车车内噪声能量主要集中在315 Hz~1000 Hz频段内,噪声主要来源于地板区域,初步推断结构为噪声主要的传递路径,可通过避开车外振动源和车体结构共振频率来减小车体的结构传声。

Virtual track trains are fast developing in China, but corresponding researches on interior and exterior noise levels, characteristics and formation mechanisms are insufficient. In this paper, based on noise source identification and sound vibration test results, the interior and exterior noise levels, spectral characteristics and its velocity dependence are analyzed. Then, according to the noise limitation standards for urban rail transit trains and automobiles, the interior and exterior noises are analyzed and evaluated. Finally, noise formation mechanisms and key control techniques are preliminarily investigated. The results show that the interior and exterior noise are respectively 69.5 dB(A)and 67.8 dB(A)when the virtual rail train runs at a constant speed of 52.5 km/h. Compared with the noise limits of urban rail transit trains and automobiles, the noise inside the virtual track train is 5.5 d B(A)and 14.5 dB(A)lower than their limits and the noise outside the train is 11.5dBA lower than the limit for urban rail transit trains. The interior noise energy is mainly concentrated in the frequency range of 315 Hz-1 000 Hz. The main noise source is mainly from in the area around the floor. It is preliminarily inferred that the structure is the main transmission path. Thus, noise reduction can be achieved by avoiding the resonance frequency of external vibration sources of the train body structure.