Study Of The Influence Of Axlebox Parameters For Dynamic Performance Of Vehicle With B₀B₀-B₀B₀ Wheelset Arrangement

In order to decrease axle-load and increase adhesion force,the vehicle with wheelset arrangement of B0B0-B0B0 has eight dirving wheelsets and smaller wheel-rail force,which can realize the high-speed transportation task on the existing railway,then ensure the safety and efficiency of railway transportation and make full use of line resources.Axlebox locating device is an important component to ensure the safety and stability of high-speed vehicle.Its main function is to provide sufficient stiffness for vehicle and reduce the vertical vibration.The axlebox of wheelset adopts rotating arm locating,which is composed of two springs,a rubber joint and a vertical absorber.Due to the vehicle boundary,there are two optional structure of axlebox spring,which are arranged at both sides or arranged in the way of centering.However,the influence of the structural parameters of axlebox on the vehicle dynamics performance still unclear.Based on this,this thesis analyzed these factors by using the comparison method and simulation method of dynamic simulation.Main research work are as follows.1)On the basis of fully investigation about heavy-haul locomotives,vehicle dynamics performance and axlebox locating device,the structure characteristics of B0B0-B0B0 wheelset arrangement vehicle its axlebox are introduced in detail,then the vehicle physical model are established according to the structural parameters provided by a domestic locomotive factory.There are four kinds B0B0-B0B0 wheelset arrangement vehicle model about combinate spring at both sides or spring in the way of centering with no-load carbody or heavy carbody.2)In the first working,when the axlebox springs arranged at both sides or centrally,the relationship between rubber joint vertical impact and spring’s stiffness ratio must be analyzed.The second working is to find the effect about rubber joint’s radial stiffness and axial stiffness for vehicle lateral stability in springs at both sides of axlebox.In the third working,we also need analyze the influence of the axlebox spring stiffness and the damping of vertical absorber for vehicle ride index when the spring are arranged at both sides of axlebox.In the fourth working,the influence of absorber damping for vertical ride index under fault conditions is studied in springs at both sides of axlebox.3)For the different primary axlebox spring arrangement,it is necessary to compare their vehicle dynamics performance.It mainly include vehicle lateral stability analysis,ride stationarity analysis and curve passing performance analysis.The results show that:When the springs is arranged at both sides of axlebox,spring’s stiffness ratio has a great effect on the maximum vertical impact of rubber joint.Using variable stiffness analysis can find an ideal stiffness ratio to minimize the vertical impact,but the stiffness ratio has no effect for rubber joint’s vertical impact maximum in centralized spring arrangement.In addition,if absorber damping is smaller,the maximum vertical impact of rubber joint will be smaller.But the radial stiffness of rhbber joint itself has no effect on the vertical impact;Tumbler radial stiffness of rubber joints,weak influence on vehicle lateral stability.The axial stiffness of rubber joints has certain influence on vehicle lateral stability,especially when vehicle is no-load,the smaller axial stiffness is,the higher nonlinear critical speed is;Reducing No.1 spring stiffness K1 can improve carbody vertical stationarity,but it has little effect on lateral stationarity at high-speed.Then No.2 spring stiffness K₂has no effect on the vehicle ride stationarity.And the smaller damping is,the better carbody vertical stationarity will be;The failure of vertical absorbers on both sides of No.1 wheelset will only make the vertical stability of the front cab worse,and the wheel-rail vertical force of No.1 wheelset also smaller.The spring arrangement has no affect the lateral stability of the vehicle.The nonlinear critical velocity of no-load vehicle is 340 km/h,and the nonlinear critical velocity of the heavy-load vehicle is 360 km/h.In the aspect of straight-track running stationarity,all ride indexes meet the evaluation standard,the spring at both sides of axlebox has a better vertical stationarity than the centralized spring arrangement.The axlebox spring arrangement has little effect on the vehicle lateral stationarity;In all curve passing working,all the evaluation indexes are less than the corresponding evaluation standards,and the arrangement of axlebox spring has little effect on the performance of the curve.