Research On Rigid-flexible Coupling Vehicle System Dynamic For ZK7Truck

Society and economy’s development make greater demands on the speed and volume of the railway freight.In this condition,Chinese railway freight develops towards high speed and heavy haul.Considering Chinese most railway is lines with passenger and freight traffic,so high speed freight cars will still run on the present lines except few overloaded lines. So Chinese railway chooses to develop low track force freight bogie which can decrease the damage caused by high speed and heavy axle loaded car that can lengthen tracks’service life.This kind of low track force freight bogie which has higher speed and higher axle load can keep the track force at the peivious bogies’level.ZK7bogie with a commercial operation speed of120km/h and an axle load of25t is a freight bogie produced by CSR Meishan Rolling Stock Works.The bogie’s radial mechanism consists of two U sub-frames connected by two cross-bars.The sub-frame with low stiffness yields high and frequently-change forces,so it might generate elastic deformation and vibration that may affect the vehicle’s dynamic performance.This paper builds the rigid-flexible coupling dynamic model and the rigid dynamic model of the gondola car C8o with two ZK7bogies installed using finite elements software ANSYS and multibody dynamic software SIMPACK. Setting the two models to be under the same conditions,simulate and calculate their dynamic performance indexes to analysis the differences between them owing to the sub-frame’s flexibility.The simulation results indicate that the sub-frame’s flexibility makes the highfrequency lataral and vertical vibration become greater.lt also indicates that the sub-frame’s flexibility can lower the vehicle’s critical speed,and it also brings the empty and loaded vehicles’curve negociation performance indexes only except the loaded vehicle’s rate of wheel load reduction at high speed.In general, the sub-frame’s flexibility can improve the vehicle’s riding and safety indexes.