Modelling And Simulation Analysis Of Vehicle System Dynamics In Consideration Of The Elasticity Of Wheelsets

The problem of vehicle-track dynamics caused by the moving of the wheel/rail contact point was presented at the beginning of railway operation. All of the vehicle components were modeled as rigid bodies in multi-body system dynamics analysis, and the elastic deformation was not taken into account. With the development of modern railway, many new techniques appear. The kinematics relations between vehicle components became more complicated. When the lightweight structures are used in high-speed vehicles, the affection of the elastic deformation of vehicle components on vehicle dynamics can not be ignored when analyzing the vehicle stability and security. Therefore, the modeling and simulation of the vehicle multi-body system dynamics were studied.The process of modeling elastic wheelsets dynamics was presented based on the analysis of wheelset structure. The dynamics model of elastic wheelset was modeled applying SolidWorks, ANSYS and SIMPACK softwares. The vehicle multi-body system dynamics model considering the wheelset elastic deformation was established based on the studies on vehicle kinematics relations and vehilce suspension structures.The elastic deformation of wheelsets appears in vehicle operation due to the structural elasticity of wheelset were considered. The simulations on elastic- wheelset vehicle system dynamics were done in order to investigating the effect of wheelset elastic deformation on vehicle dynamics. The elastic-wheelset vehicle critical speed was obtained by analysing the history of lateral displacement of elastic wheelset. Then the vehicle running stability can be confirmed. The vehicle riding quality under the excitation of German high speed track spectrum was analyzed. The wheel/rail lateral force, the wheel/rail vertical force, the wheel/axle force, the reduction rate of wheel load and the derailment coefficient were simulated and analyzed when vehicles run on different curves. The results simulated by the elastic-wheelset vehicle system dynamics and the rigid-wheelset vehicle system dynamics were compared. The results show that the vehicle critical speed reduces and the vehicle riding quality and the curve negotiation performance are affected a little when the elastic deformation of wheelsets are considered.