Modeling and Simulation of High Speed Railway Vehicle Dynamics

This study aims to provide mathematical model(s) for the simulation of high speed railway vehicles. The dynamic behavior of a high speed train is divided into three uncoupled motions: vertical, lateral, and longitudinal. Two models with different complexities are used to simulate vertical plane response of the vehicle to track vertical irregularities. Different wheel-rail contact formulations are utilized to simulate the lateral plane motion of the vehicle on tangent and curved tracks. For both vertical and lateral dynamics modeling, a single wagon is assumed to simulate the whole vehicle. Finally, wagon interactions are taken into account and the response of a full train to different traction/braking inputs are analyzed. The models are parametric and they are used to develop computer programs to simulate train motion. Using a set of parameters obtained from literature, different case studies were performed to test model functionality. It was observed that 10 degree of freedom model can predict the vertical behavior quite well. In wheel-rail contact modeling, the nonlinearities should be included in the system and the wheel profile with its tread and flange sections should be introduced to obtain accurate results. Finally, in longitudinal dynamics modeling, the stopping time and distance between wagons with respect to braking delay and wagon to wagon connection are examined