Numerical Simulation of the Aeroacoustic Performance of the DSA380 High-Speed Pantograph Under the Influence of a Crosswind

摘要

The object of research of this paper is the DSA380 high-speed pantograph.The near-field unsteady flow around the pantograph was investigated using large eddy simulation(LES)while the far-field aerodynamic noise was analysed in the frame of the Ffowcs Williams-Hawkings(FW-H)acoustic analogy.According to the results,the contact strip,base frame and knuckle are the main aerodynamic noise sources,with vortex shedding,flow separation and recombination around the pantograph being related key physical factors.The aerodynamic noise radiates outwards in the form of spherical waves when the distance of the noise receiving point is farther than 8 m.The sound pressure level(SPL)grows approximately as the 6th power of pantograph operating speed.The aerodynamic noise energy is mainly concentrated in the region of 400-1000 Hz,and the frequency band is wider with crosswind than without crosswind.The peak frequency displays a linear relationships with the operating speed and crosswind velocity,respectively.The aerodynamic and aeroacoustic generation from the knuckle-downstream orientation of the pantograph is superior to those of the knuckle-upstream orientation model.This finding may be used for the optimal design of future pantograph configurations in the presence of crosswind.