SUMMARY
The main intention of this research work is to study the derailment response of high-speed railway vehicles (HSRV) cruising on a curved track. In previous research work, a lower degree of freedom (DOF) has been considered for the derailment analysis which may not give more accurate results. Hence, a 31 DOF bond graph model of HSRV has been developed which consists of a car body, two truck frames, and two selfsame wheelsets for each truck frame. Vertical, lateral, roll, yaw, and pitch motion are considered for car body and bogie and except pitch motion, all the other motions are considered for wheelsets. Non-linearities in terms of heuristic nonlinear creep model and flange contact has been employed to simulate the derailment response at high speed. The effect of vehicle speed running on a curved track was investigated for derailment quotient. The main aim of the present research work is to evaluate the derailment quotient at the speed range of 150 kmph to 600 kmph for hard and soft suspension parameters. Derailment quotient has been calculated for both linear and nonlinear creep models and it is seen that DQ for the linear model has a lower value compared to non-linear creep. The major advantages of the proposed model are that the presented model can actively predict the derailment of a railway vehicle, and also precisely determine the nonlinear critical hunting speeds.