High-center-gravity Vehicle Dynamic Simulation Analysis Of Rigid-flexible Coupling

In the background of that the railway freight transport is developing to heavy haul and quick urgently, in order to release modern technology of freight transport,a vehicle factory developed a new 6-axle double-deck container vehicle ,with high center of gravity. The vehicle not only uses double deck method to load and high gross rail load on axle to make heavy duty true, but also makes the velocity request upgrade one step ,try to make good performance in 100-135km/h true to be able to have the ability of quick transport.In order to research the performance of the prototype vehicle in all kinds of conditions. The article use the ADAMS/Rail software to analyze 6-axle double-deck container vehicle by dynamic simulation method. The process of simulation is as follows: using the technology of template-building model, the strategy of flexible body interface processing, interface-locating subsystem assembled ,rigidity-loading method and so on to model the whole vehicle and 3-unit vehicle; next,conducted a vehicle modal analysis and critical velocity analysis,obtained that typically movement modal of vehicles,body structure modal results and critical speed in the condition of the empty vehicle. And also designed the straight line and 4 kinds of curved line with AAR5 track irregularity, in which to carry out test in the velocity of 60-135km/h,then obtained the car body's data in detail which contains evaluation of stability and wheel-track security evaluation in longitudinal/lateral/vertical direction. The stability evaluation considered the influence of frequency more .To analyze simulation results above-mentioned showed that the 3-unit vehicle have poor lateral stability in the condition of no-loading; the vehicle's vertical stationary influenced high by high-frequency vibration in the condition of heavy loading; and in the aspect of wheel-rail safety, the data in the condition of no-loading and heavy-loading test all reflect that the relationship of 3 wheelsets is out of line. Otherwise, the article directs to the vehicle'stationary and wheel-rail safety evaluation increased sharply in the high-speed section,conducts the 3-axle frame bogie performance simulation argument, the bogie showed 3 problems: the axlebox bearing saddle's sliding problem,the stationary problem of mid-wheelset in the condition of heavy loading,car body's structural vibration followed with movement modal.Based on the problems above ,the article referred to some materials to raise and verify the following countermeasures:â‘ uses 45deg inclined plane as bearing plane to increase the equivalent friction coefficient value and decrease longitudinal clearance between bearing saddle and axlebox in the model;â‘¡uses the modified wheel tread B with rim 23mm instead of the prototype tread in the second wheelset based on wheel-rail matching theory;â‘¢Strengthens the car body's stiffness and adds the wedge damping instrument in the bogie's 2nd wheelset to raise the longitudinal stiffness of wheelsets. At last, the article uses the combined method of modal analysis and frequency response analysis verified the feasibility of the improving. Among of these,the axlebox bearing saddle's sliding problem and the stationary problem of mid-wheelset disappeared; the wheel-rail force decreased by more than 30%,3 wheelsets force tends to balance ;the car body's lateral vibration and vertical high-frequency vibration clearly decreased .