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Numerical Analysis of Aerodynamic Noise of a High-Speed Pantograph

The aerodynamic noise of pantograph is one of the most important noise sources of high speed trains. Therefore, the reduction of the aerodynamic noise of pantograph becomes very important for reducing the total noise level of the high-speed trains. In this paper, the distribution of dipole sound sources at the surface of a single-arm pantograph and the noise radiation from it are predicted numerically by the combination of incompressible fluid flow analysis using the finite element method (FEM) and acoustic analysis using the boundary element method (BEM) at speed of 300km/h. The objectives of this calculation are to locate the noise sources on the surface of this type of pantograph and to understand the mechanism of the aerodynamic noise radiation. The analysis results indicate that: the aerodynamic noise of the high-speed pantograph is induced by the vortex shedding, the main noise sources of this single-arm pantograph are the pantograph head, knee, arms around knee and foot region, the aerodynamic noise of this type of pantograph is mainly the low-frequency and mid-frequency noises.