某型受电弓300km/h速度下气动噪声初步分析

Preliminary Investigation into Aerodynamic Noise of A Certain Type of Pantograph under Speed of 300 km/h

建立了某型受电弓的三维几何模型,基于计算流体动力学基本原理及有限体积元方法,对该型受电弓周围流场进行模拟,并建立了受电弓的气动噪声计算模型,利用声类比相关理论对受电弓纵向对称平面上的气动噪声进行计算。列车300km/h速度运行时,受电弓开口和闭口运行2个工况下,旋涡集中分布的区域、气动噪声较大值出现区域和受电弓气动声源所在区域相重合,主要分布在受电弓垂直于气流方向的杆件表面或杆件后面。受电弓开口运行时,引起更大的气动噪声,开口运行时对称平面上气动噪声仿真的最大值出现在受电弓上臂与下臂之间的铰接部位,为130.5dB(A)。最后将仿真结果与实验结果进行对比,受电弓开口运行时底座中心附近的气动噪声仿真值为120.1dB(A),实验结果值为122.5dB(A)。闭口运行时仿真结果为116.8dB(A),实验结果为120.6dB(A)。

This paper developed a three-dimensional geometric model of a pantograph, to simulate the flow field around the pantograph based on the basic principle of computational fluid dynamics and the finite volume element method.A calculation model of aerodynamic noise of the pantograph was also established to calculate the aerodynamic noise on the longitudinal symmetry plane of the pantograph based on the Acoustic Analogy Theory. When the train ran at a speed of 300 km/h in both directions, the vortex core region, the aerodynamic noise area and pantograph＇s pneumatic sound source area overlapped, which were mainly distributed on the surface of or behind the arms of the pantograph perpendicular to the airflow. A higher level of aerodynamic noise on the symmetry plane occurred when the train ran with the ＂knuckle＂ between the pantograph arms facing backward. The maximum value, 130.5 dB（A）, of aerodynamic noise by simulation, appeared at the ＂knuckle＂ between the upper arm and lower arm of the pantograph. Finally, the simulation results and experimental results were compared. When the train ran with the pantograph ＂knuckle＂ facing backward, , the simulation value of aero- dynamic noise near the base center was 120.1 dB（A）, while the aerodynamic noise value of the experimental result was 122.5 dB（A）. When the pantograph ＂knuckle＂ faced forward, the simulation value of aerodynamic noise was 116.8 dB （A）, while the aerodynamic noise value of the experimental result was 120.6 dB （A）.