Abstract
A broadband noise source model based on Lighthill’s acoustic theory was used to perform numerical simulations of the aerodynamic noise sources for a high-speed train. The near-field unsteady flow around a high-speed train was analysed based on a delayed detached-eddy simulation (DDES) using the finite volume method with high-order difference schemes. The far-field aerodynamic noise from a high-speed train was predicted using a computational fluid dynamics (CFD)/Ffowcs Williams-Hawkings (FW-H) acoustic analogy. An analysis of noise reduction methods based on the main noise sources was performed. An aerodynamic noise model for a full-scale high-speed train, including three coaches with six bogies, two inter-coach spacings, two windscreen wipers, and two pantographs, was established. Several low-noise design improvements for the high-speed train were identified, based primarily on the main noise sources; these improvements included the choice of the knuckle-downstream or knuckle-upstream pantograph orientation as well as different pantograph fairing structures, pantograph fairing installation positions, pantograph lifting configurations, inter-coach spacings, and bogie skirt boards. Based on the analysis, we designed a low-noise structure for a full-scale high-speed train with an average sound pressure level (SPL) 3.2 dB(A) lower than that of the original train. Thus, the noise reduction design goal was achieved. In addition, the accuracy of the aerodynamic noise calculation method was demonstrated via experimental wind tunnel tests.
Highlights
With the high running speeds of high-speed trains, problems that can be neglected at low speeds become sufficient to limit improvements in train speed [1, 2]
High-speed railway noise is evaluated in terms of the A-weighted equivalent continuous sound pressure level (SPL) (LpAeq,T)
Optimizing the structures of the main noise sources can lead to effective noise reduction
Summary
With the high running speeds of high-speed trains, problems that can be neglected at low speeds become sufficient to limit improvements in train speed [1, 2]. Rough areas on the train severely disturb the airflow at high speeds, thereby generating complex flow separation and vortex shedding phenomena; the resulting powerful fluctuations in air pressure in the far field translate into aerodynamic noise. This source can be predominant in case of the high-speed train is running behind a ∼4 m high noise barrier as the pantograph is higher than the noise barrier. Yamazaki et al [20] found that the inter-coach spacing is a major noise source for high-speed trains by conducting wind tunnel experiments and field tests using a 1 : 5 scale Shinkansen train model. Wind tunnel tests were performed to thoroughly verify the correctness of the numerical analysis method used in this paper
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
