基于仿生非光滑结构的高速列车受电弓杆件减阻降噪研究

Study on Drag and Noise Reduction of Pantograph Rods based on Bionic Non-smooth Structures

高速列车受电弓产生的气动噪声会向周围环境直接辐射,成为列车的主要噪声来源之一。受电弓主要由杆件组成,因而针对杆件结构进行空气动力学研究对于受电弓减阻降噪具有重要意义。选取受电弓杆件的典型尺寸建立有限元仿真分析模型,采用Realized k-e湍流模型及宽频噪声模型分别计算流场分布及气动噪声大小。研究受电弓气动噪声产生的机理,对杆件截面形状进行了优化改进,并在此基础上根据鸮的前翼边缘锯齿型结构及潮间贝类的波纹凹槽结构对杆件进行仿生设计。最后,通过数值计算对各类仿生改进设计效果进行对比分析。结果表明,环状波纹凹槽杆件结构为最优的仿生设计,可以实现明显的减阻降噪效果;相对于背风侧带锯齿的杆件结构,迎风锯齿的仿生设计可以有效降低气动噪声,但会使气动阻力增加。

The aerodynamic noise generated by the pantographs of high-speed trains directly radiates to the surrounding environments and becomes one of the main noise sources of the trains. Since the rod is the main component of the pantograph structure, it is of great significance to study the aerodynamics of the rod structure for the reduction of noise and drag of the pantograph. In this paper, the finite element model of a typically sized pantograph bar was established for simulation analysis. The Realized k-e turbulence model and the broadband noise model were used to calculate the flow field distributions and aerodynamic noise magnitudes respectively. The mechanism of aerodynamic noise generation was investigated, and the shape of the cross-section of the rod was optimized. Furthermore, the bionic design of the rod structure was carried out according to the zigzag structure of front wing edge of the owl and the corrugated groove structure on the outer surface of intertidal shellfish. Finally, the effects of all kinds of bionically improved design were compared and analyzed through numerical calculation. The results show that the structure of annularly corrugated groove member is the best bionic design, which can achieve obvious drag reduction and noise reduction effects. And compared with the leeward side zigzag structure, the bionic design of windward side zigzag structure can effectively reduce aerodynamic noise, but it will increase the aerodynamic drag.