Mutual Transition Condition Between Hunting Motion Stabilization And Instability Oscillation Of Self-Adaptive High-speed Bogie

Regardless of normal or harmful wear,the geometric nonlinearity of wheel rail contact will force the wheel to produce spin creep and form rolling resistance moment.Therefore,the hypothesis of small creep and no spin is no longer tenable.As a result,the longitudinal traction kinetic energy is partially transformed and becomes the transverse energy of unstable hunting oscillation.The stability of hunting motion is conditional,so the adaptive high-speed bogie should scientifically improve the limit and construction speed under the condition of reasonable wheel rail matching.Considering a snaking of an imported prototype and its influence,both theoretical and experimental studies can prove that: when λe <0.10,a low-taper high-speed sway car occurs;when λe ≥0.10,there is a causal relationship between bogie vibration early warning and vehicle shaking,which makes it difficult to improve the limit and construction speed.In order to lead the adaptive improvement design of high-speed bogie.In this study,the stability analysis diagram of the whole vehicle is used to transform a very difficult snaking into a simple problem of vehicle body instability.When λe <0.10,the wheel load shedding rate becomes one of the main restricting factors of lifting speed.Therefore,the adaptive high-speed bogie not only obtains a long uniform wear period,but also can realize the self-cleaning of the tread wear of the central depression across the railway special line with different speed levels.When λe =0.10,the dynamic simulation analysis shows that the limit speed is increased from 480 km/h to 650 km/h.On the premise of removing and eliminating the causal relationship and negative effects between bogie vibration warning and shaking,it can be proved that when λe ≤0.16,the adaptive high-speed bogie has the ability to break the highest speed of 575 km/h in the world.For high-speed special railway lines,the occurrence probability of track taper(0.25-0.35)needs to be controlled below 5% by rail inspection vehicles.Therefore,the adaptive improved design finally has the conditions to realize low taper uniform wear.If the track has a reasonable curve to straight ratio,it can not only realize economic lathing,but also realize the three-stage wear law of uniform,fast and stable.