Research On Dynamics And Dynamic Comfort Of Multi-Vehicle Marshalling For High-Speed Trains

With the development of high-speed train technology,the vehicle speed is getting faster and faster,the convenience and comfort have become the new development trend of the high-speed vehicles.The increase of running speed will increase the interaction force between wheel and rail,reduce the comfort level and affect its dynamic performance.At the same time,the increase of vehicle speed also leads to the increase of longitudinal force between vehicles,and the dynamic performance of marshalling vehicles has become one of the important issues that people pay close attention to.The research in this paper mainly includes:(1)According to the topological relations,structure of the vehicle carbody and bogie and its dynamic parameters,the multi-rigid-body dynamic models of the one vehicle and 8 vehicles marshalling are established in the multi-body dynamics analysis software SIMPACK.(2)According to the corresponding line conditions,the straight line segment and the curved segment are set respectively,choosing the German high-speed low interference spectrum as excitation,the dynamic simulation calculation of the high-speed vehicle is carried out.The dynamic performance of the high-speed train is analyzed.The stability includes the linear critical speed and nonlinear critical velocity of the vehicle.The evaluation indexes of safety include the vertical force of the wheel and rail,the transverse force of the wheel and rail and the derailment coefficient;Comfort is evaluated according to Sperling index.(3)Taken the single vehicle model as the research object,the influence of the axle box positioning device,the primary spring stiffness,the primary vertical damper and the stiffness and damping of the second suspension on the linear critical speed,the nonlinear critical speed,the safety and the comfort of the vehicle are analyzed,and the variation of the dynamic performance with the suspension parameters of the vehicle is studied and analyzed,so the optimal suspension parameters are determined.(4)On the basis of the single vehicle simulation,the coupler buffering device and the longitudinal damper between vehicles are established by using of No.43 and No.6 force element in the SIMPACK,and so the multi-body dynamic model of the 8 vehicle marshalling is established.The safety of the train passing through the curve,the comfort of the straight line,and the variation of the train coupler force under the braking and starting are studied and analyzed.(5)By adjusting the size of the coupler clearance,the change laws of the safety and comfort of the marshalling vehicle are studied and analyzed.At the same time,the situation of the brake malfunction is studied,and the change characteristics of the coupler force between the vehicles are studied.The results show that the selection of the appropriate coupler clearance is beneficial to the safety of the marshalling vehicle of passing through the curve,especially it is good to reduce the vertical force between the wheel and rail of the tail vehicle.The study shows that the coupler clearance has little effect on the comfort of the marshalling vehicle,and the coupler force will increase in the case of the brake failure.