New Designing Procedure for Pantograph of High-Speed Trains

In Japan, several projects to increase train speed are underway, requiring a new generation pantograph that achieves further reduction in aerodynamic noise. However, as reduction of pantograph noise usually conflicts with the stabilization of its lift force characteristics, a number of experiments have to be conducted to develop a new type of pantograph. The aeroacoustic and lift force characteristics of the pantograph depend largely on the design of the panhead; therefore, the authors have attempted to systematically modify the aeroacoustic and lift force characteristics of the panhead using techniques of shape optimization and flow control technique, as well as an innovative flow visualization technique. The optimization technique can analytically propose a panhead shape with low aerodynamic noise and stable lift force characteristics. The flow control technique regulates the pantograph’s lift force characteristics using jet ejection. The flow visualization technique using pressure-sensitive paint (PSP) gives detailed image of pressure distribution with high spatial resolution in wind tunnel testing, enabling the pressure distribution on the pantograph to be observed directly. As aerodynamic interaction between the panhead and the articulated system strongly affects aeroacoustic and lift force properties of the pantograph, the visualization of pressure distribution provides useful information for pantograph design. This paper outlines the new design procedure of the pantograph for high-speed trains and gives details of some experimental results.