Rigid-flexible Coupling Dynamics Analysis Of High-speed Passenger Cars By UM

The rail vehicle is an extremely complex system.In order to simplify the study of the vehicle system,the vehicle system is usually considered as a multi-rigid body and the elastic deformation of the components of the vehicle system is ignored.With the continuous improvement of the running speed of the train,the safety,stability and comfort of the vehicle system are increasing,so it is necessary to consider the elastic vibration of the components of the vehicle system.Based on the theory of rigid-flexible coupling dynamics,combined with finite element analysis software ANSYS and multi-body dynamics software UM,the framework of CRH2 high-speed passenger car is considered as elastomer.The safety,stability and curve performance of the vehicle are analyzed.Firstly,the 3D solid model of the architecture is established in three-dimensional solid modeling software SolidWorks.In order to explore the influence of the elastic deformation of the frame on the dynamic performance of the vehicle,the stiffness matrix is calculated by the finite element software ANSYS,and the frame is transformed into the flexible body by combining UM_ANSYS.Finally,the rigid-flexible coupling dynamics model of CRH2high-speed passenger car is established in the multi-body dynamics software UM.Secondly,in order to study the vibration characteristics of the flexible frame and the influence of the frame flexibility on the operational safety and the curve passing capacity of the vehicle system,the vibration characteristics of the multi-rigid body model and the rigid-flexible coupling dynamic model are compared and analyzed.The nonlinear critical speed and the dynamic parameters of the curve passing of multi-rigid body model and rigid-flexible coupling dynamic model are calculated.The results show that the elastic deformation effect of the frame increases the nonlinear critical speed of the vehicle,and also affects the running stability and curve passing performance of the vehicle.Then,the coupling dynamic model of wheel-rail wear is established,and the distribution and development of wheel surface wear are studied by using Archard abrasion prediction method.The influence of wheel wear on the dynamic parameters of the vehicle system is analyzed by comparing the multi-rigid body model and the rigid-flexible coupling dynamic model.The influence of the frame flexibility on the wheel-rail wear is explored.The results show that the elastic deformation effect of the frame reduces the calculated value of the safety index of the vehicle system after wheel wear.Finally,the vehicle-track-bridge coupling system is established.The influence of the flexibility of the frame on the vibration characteristics of the bridge,the vibration characteristics and the dynamic characteristics of the vehicle under different working conditions are compared analyzed.The influence of frame flexibility on the vibrationcharacteristics of the bridge when the vehicle is passing the bridge and the operational safety,stability of the vehicle.The results show that the elastic deformation effect of the frame reduces the dynamic performance of the vehicle-track-bridge coupling system.