Numerical modeling and experimental evaluation of an high-speed train pantograph aerodynamic noise

Several studies to increase train speed are underway with the target to design a new generation pantograph in order to reduce aerodynamic noise. The aerodynamic characteristics as shapes of pantograph are the main issue. The present work deals with a high-speed aerodynamic and aeroacoustic analysis of a three-dimensional pantograph model, through the employment of 3D numerical simulations. In particular, a computational fluid dynamics-based analysis is performed using commercial software code FLUENT AnsysTM and an experimental campaign is performed in the high-speed wind tunnel in order to verify the accuracy of numerical approach. The aerodynamic noise is, then, calculated through the Ffowcs Williams--Hawkings (FW-H) equation to evaluate the flow induced sound pressure level in aeroacoustics. The numerical and experimental results are then compared in terms of sound pressure levels and a well agreement has been found. The numerical results in terms of visualization of pressure distribution on the pantograph provides useful information for pantograph design. The results highlight the possibility to develop a new design of the pantograph for high-speed trains, in order to obtain an aerodynamic noise reduction