Analysis of Wind Noise from a Train Pantograph Cover

Public transportation systems that pass through densely populates areas should generally be as quiet as possible. High-speed trains present noise problems because of their size, operation speeds, and the proximity of homes. An important source of wind noise on trains is the pantograph system which is used to supply electrical power from overhead lines.

The objective of this project was to predict the wind noise from the pantograph cover on a high-speed train. The general approach is to divide the problem into two parts: a flow calculation to determine the unsteady air flow generating the sound and an acoustics calculation to determine the sound propagation. The unsteady fluid flow problem was solved using a large-eddy simulation (LES). The resulting pressure histories on the cover were then used to predict the radiated sound using a boundary element method to solve the Helmholtz equation.

The pantograph and aerodynamic cover being analyzed is shown in Figure 1. The calculation of the unsteady flow over the pantograph cover to predict the pressure fluctuations over the model surface was performed with the SPECTRUM solver. The results of this unsteady flow simulation are shown in Figure 2. The results of the flow simulation were then used to predict the radiated sound using the RAYON acoustics code. More details of this program are available in the reference below.

For inquiries or comments, please contact:
Robert MacNeill
Principal Engineer
e-mail: rmacneill@ara.com