Keywords: forced vibration, aerodynamic force, comfort in riding, inter-vehicle lateral damper, equivalent single-car model.

In recent years, with the speed-up of Shinkansen trains, an increase in the car body lateral vibration caused by the aerodynamic force acting in tunnel sections has been noted. The vibration of railway vehicles is excited not only by the aerodynamic force in tunnel sections but also by track irregularities. The damping coefficients of the lateral damper, which is installed between the car body and truck, have been determined on the basis of the premise of excitation from track irregularities. Thus the effect of the lateral damper against the excitation of aerodynamic force is not expected even if the damping coefficient is made larger. In addition, anti-rolling devices which are also installed between the car body and trucks cannot suppress the vibrations in the wide frequency range excited by both disturbances. Therefore, it seems to be difficult for devices installed between the car-body and truck to suppress the running vibrations caused by both aerodynamic force and track irregularities at the same time.

In this study, by means of numerical analysis, we investigated the possibility of installing inter-vehicle lateral dampers between car bodies to reduce the running vibrations caused by the two types of disturbances. Here, considering the characteristics of intermediate cars in a long train, an equivalent single-car model [1] is utilized for ease in the analysis of the effect of the inter-vehicle lateral damper. The analysis using the equivalent single-car model is divided into two cases: one is and operation on an open section with excitation only by track irregularities, and the other is operation in a tunnel section with excitation caused only by aerodynamic forces. Then, the practical effect of the inter-vehicle damper on vibration suppression is verified by utilizing a train model with eight coupled cars [2], in the range of damping coefficients with which the inter-vehicle lateral damper is expected to be effective in the equivalent single-car model.

The equivalent single-car model showed qualitatively that the inter-vehicle lateral damper has the potential to reduce car body vibration upon increasing its damping coefficient. Then, the effect of the inter-vehicle lateral damper was verified quantitatively using a train model. Here, it was also suggested that the riding comfort can be improved by installing the inter-vehicle lateral damper under the gangway between cars.

1

H. Fujimoto, "Research on Dynamic Influences of Vehicle Coupling and Vibration in Running Railway Vehicles", RTRI Report, Special 29, 47-65, 1995.

2

K. Tanifuji, K. Sakanoue, S. Kikko, "Modelling of aerodynamic force acting on high speed train in tunnel and a measure to improve the riding comfort utilising restriction between cars", Supplement to Vehicle System Dynamics, 46, 1065-1075, 2008. doi:10.1080/00423110802158747

purchase the full-text of this paper (price £20)

go to the previous paper
go to the next paper
return to the table of contents
return to the book description
purchase this book (price £145 +P&P)