高速列车车头的气动噪声数值分析

Numerical Analysis on Aerodynamic Noise of the High-speed Train Head

随着列车运行速度的提高,列车气动噪声变得越来越明显,降低气动噪声已成为控制高速列车噪声的关键之一。本文对高速列车车头气动噪声进行数值分析。首先,建立高速列车三维绕流流场的数学物理模型,分别利用标准k-ε湍流模型和大涡模拟计算高速列车的外部稳态和瞬态流场。然后,基于稳态流场,利用宽频带噪声源模型计算高速列车车身表面气动噪声源;基于瞬态流场,分析车身表面脉动压力的时域及频域特性;利用Lighthill声学比拟理论,计算高速列车远场气动噪声,分析远场气动噪声的时域及频域特性。本文对研究和控制高速列车气动噪声具有一定意义。

Along with the raising of the train speed, aerodynamic noise of the high-speed train are generated more and more significantly and their reduction has become one of the key factors to control noises of the high-speed train. In this paper, aerodynamic noise radiated from the high-speed train head surface are analyzed numerically. The mathematical and physical models of the three dimensional flow field of the high-speed train areestablished and the external steady and unsteady flow fields of the high-speed train are calculated by using the standard k-ε turhulence model and large eddy simulation （LES） respectively. On the basis of the steady flowfield, aerodynamic noise sources on the car body surface of the high-speed train are calculated by using the broadband noise source model. On the basis of the unsteady flow field, the time domain and frequency domaincharacteristics of fluctuating pressures on the car body surface are analyzed. The far-field aerodynamic noise of the high-speed train are calculated by applying the Lighthill acoustic analogue theory and the time domain andfrequency domain characteristics of aerodynamic noise in the far-field are analyzed. The computational research is significant to study and control of aerodynamic noise of the high-speed train.