Influence of Arc and Conic Profile on Vehicle Dynamics. An Evaluation from Input Energy and Kinematic Oscillation.

Abstract

It is found through vehicle dynamics simulation that a carbody hunting motion for arc tread wheel becomes smaller than that for conic tread wheel in new type SHINKANSEN train which is bolsterless and has soft suspension between carbody and bogie. Then we studied about the reason, comparing kinematic hunting wave length of a bogie with the natural frequency of the carbody and also evaluating input energy from rail to vehicle. The analysis shows that vehicle with arc profile treat has high frequency from short kinematic wave length in a high speed (270 km/h) whereas low carbody natural frequency, then the frequency of carbody hunting motion becomes apart from the natural frequency and smaller than that with conic profile. In addition, the energy input from rail to vehicle were calculated from simulation and verified the validity of relation between the carbody natural frequency and hunting characteristics. An arc profile that varies with lateral displacement of wheelset also shows that the energy input from rail is smaller than that in a conic profile.