高速列车气动噪声源远场噪声贡献度研究

建立3辆车编组高速列车气动噪声计算模型,包括1辆头车、1辆中间车、1辆尾车、6个转向架和1个受电弓,利用标准k-ε湍流模型和大涡模拟分别计算列车的外部稳态和瞬态流场,并基于瞬态流场用FWH方法计算高速列车远场气动噪声。计算单个转向架、全部6个转向架、车体头部、车体尾部、车体中间部、全部车体、受电弓、列车整体分别为噪声源时的远场辐射噪声,分析这些噪声源对远场噪声评估点的总声压级,以及不同噪声源对远场噪声的贡献,以验证局部气动噪声源对远场辐射噪声与整体噪声源之间的叠加关系。计算结果表明:车体是高速列车远场辐射噪声的主要噪声源,其次是受电弓,转向架对远场辐射噪声影响相对较小;从局部噪声源来看,车体头部、受电弓、头部第1个转向架是高速列车远场辐射噪声的主要噪声源;各局部气动噪声源远场噪声的叠加值与整体气动噪声源远场噪声一致,验证了高速列车整体噪声源与其包括的各局部噪声源符合声源叠加原理。

Far Field Noise Contribution Radiated from Aerodynamic Noise Source of High-Speed Train

The computational model for the aerodynamic noise of a three-car formation high-speed train was established, including a head car, a middle car, a tail car, a pantograph and 6 bogies. The external steady and transient flow fields of trains were calculated by using the standard turbulence model and large eddy simulation (LES), respectively. Based on transient flow field, the far-field aerodynamic noise of high-speed train was calculated by FW-H method. The far-field radiation noises were calculated respectively under the noise sources of a single bogie, all 6 bogies, the head of car body, the tail of car body, the middle of car body, the whole car body, pantograph and the whole train. The overall sound pressure levels of these noise sources at the far-field noise evaluation points and the contributions of different noise sources to far-field noises were analyzed so as to verify the superposition relationship between the local aerodynamic noise source, the far-field radiation noise and the overall noise source. Calculation results show that the car body is the main noise source for the far-field radiation noise of high-speed train, followed by pantograph, and the influence of bogie is relatively small. From local noise sources, the head of car body, pantograph and the first bogie at the head car are the main noise sources for the far-field radiation noise of high-speed train. The superposition of far-field noises of each local aerodynamic noise source is consistent with the far-field noises of the whole aerodynamic noise source. It is verified that the whole noise sources and all local noise sources of high-speed train conform to the superposition principle of noise source.