The reduction of aerodynamic noise emitted from pantographs along with the increasingly higher speeds of Shinkansen trains has become a major challenge. Accordingly, the RTRI developed an effective technique to reduce aerodynamic noise from panheads, panhead supports, knuckle and baseframe, which represent the main sources of pantograph aerodynamic noise.

With panheads, which contribute more to aerodynamic noise, it is required to achieve reduced noise while maintaining appropriate lift characteristics. The RTRI therefore developed panhead shape-optimization method through a technique that combines numerical computation in the flow field and optimization theory, and proposed a new panhead shape featuring reduced noise and stable lift characteristics similar to currently-used panheads. The Institute also proposed a panhead support configuration that prevents the induction of aerodynamic noise caused by aerodynamic interference between the panhead and the articulated frame, and created a prototype pantograph. A noise reduction technique involving the pasting of porous materials was also developed for use with relatively large members such as knuckle and baseframe.

The results of applying these techniques to Shinkansen pantographs (Fig. 1) and verifying their aerodynamic noise reduction effect in RTRI’s large reduced-noise wind tunnel confirmed an aerodynamic noise reduction of about 4 dB(A) in overall (OA) value relative to currently-used pantographs (Fig. 2).