Aerodynamic problems arising in high‐speed train development

The aerodynamic problem, which has not been a serious one previously in the field of train technology, is now becoming serious as the train speed is increased: aerodynamic noise, aerodynamic drag, train oscillation, and structural damage, etc. Of these, the present investigation deals with the aerodynamic problems concerned with the shapes of a nose coach and a pantograph, which are the most important portions to be improved in the train system as far as the train aerodynamics and noise are concerned. Using a recently constructed low‐noise, low‐turbulence small wind tunnel, systematic investigations have been conducted experimentally, and new shapes for those train components are being developed and suggested for future high‐speed train systems. Especially, a detailed investigation was done for the insulator (Gaishi, in Japanese), and a low‐noise insulator was developed.