Study On Rigid-Flexible Coupling Modeling Of Vehicle And Vibration Reduction Of Suspended Equipments Based On Model Updating

The rapid development of high-speed vehicle technology has brought great convenience to people’s life.To increase the speed of the vehicle,lightening design of carbody and the type of distributed power are adopted.The lightening design greatly reduces the quality of the carbody,which improves the speed and reduces the wheel-rail force.At the same time,it leads to stiffness deficiency of the carbody,which seriously affects the stability and ride comfort of the vehicle.The type of distributed power reduces the axle load.But many equipments of different qualities are suspended under the carbody and some of the equipments have excitation source.For this reason,the coupling vibration is easy to occur between underframe equipments and carbody which affects the dynamic performance of the vehicle.In order to reduce the vibration of the carbody and improve the ride comfort,it is necessary to study the coupling vibration between carbody and underframe equipments,then find the control method.The accuracy and reliability of the dynamic model are the necessary prerequisites for these studies,which directly affects the analysis results of vehicle dynamics problems.This paper studies the modeling and updating methods of various substructures of carbody.Firstly,this paper studies the finite element modeling method of the composites passenger compartment floor.Then through the analysis of laminated plate theory and the comparison between simulation and experiment,the modeling scheme of the floor is determined.Secondly,this paper discusses the equivalent modeling method of the composite section structure,which greatly affects the accuracy of dynamic analysis.Based on the results of experimental modal identification,the model updating of the passenger compartment floor and composite section structure are completed,which reduces the deviation between the simulation model and the experiment model,and verifies the feasibility of the modeling method.Thirdly,this paper studies the equivalent modeling and updating method of the white carbody and fully equipped carbody,and realizes the integration of finite element model into multibody dynamics software.Based on the stability evaluation criterion and the analysis of modal contribution,this paper studies the choice of flexible structure.Then the finite element model and the rigid-flexible coupling model reflecting the dynamic characteristics of the real structure are obtained.Finally,based on the simulation model,this paper studies the influence of the equipments on the carbody vibration and compares the influence of rigid suspension and elastic suspension on the dynamic performance of the vehicle.Through the analysis of the equipment quality,suspended stiffness and suspended damping,this paper studies the matching design method of the equipment suspended parameters.According to the principle of dynamic vibration absorber and the principle of passive vibration isolation,the optimal scheme of suspended parameters is obtained.