Improved Design Of Self-Adaptive High Speed Bogies Based On Full-Vehicle Stability Properties And Variation Patterns

Harmful wear is one of the common technical problems existing in the operation and maintenance practice of high-speed railway in the world.For example,there is a snaking design defect in the German ICE3 series bogie prototype,which constitutes the fundamental reason for the formation of tread concave wear.However,the bottom slope of CN60KG rail in China is 1/40,and the wheel rail gap on each side is reduced by 3.5 mm,so the initial contact area of rail deviates from the center line of rail head to the side of gauge angle,so it is not easy to carry out excessive rail head modification.Therefore,the advanced improved augmented method is applied to reveal the influence of wheelset self stability and singularity change of complex constraints,and then the formation mechanism of wheel tread concave wear and its countermeasures are discussed.Considering the restriction of one-time hunting on the wheel rail matching conditions,the wheel cumulative tread concave wear can not be eliminated or removed regularly by cross line operation.According to the energy absorption mechanism of anti hunting（wide）frequency band,the improvement scheme of adaptive fast/high speed bogie is formulated.Taking MC01（the first motor car）as the research object,the dynamic simulation of high-speed running shows that the equivalent taper is the best Whenλ_{e N}is reduced to 0.06,the slight shaking of the head in the initial stage can be used to clean up the harmful wear in time;The wheel tread wear presents obvious uniform,stable and rapid wear law;The accumulated tread concave wear and its negative effects can be eliminated regularly by using the wheel across the line.The whole vehicle stability analysis diagram uses big data mining methods such as orthogonal decomposition or design mode to clarify the technical transformation direction of the adaptive bogie and eliminate the singularity of complex constraints such as one-time hunting.Using Newmark second-order difference algorithm,nonlinear simulation can further verify the dialectical relationship between（near）linear and nonlinear of actual wheel rail contact.Through the collaborative innovation efforts of vehicle and rail specialty,under the condition of reasonable wheel rail matching,scientifically formulate the repair system and optimize the operation and maintenance cost.The whole vehicle stability analysis chart is the best optimization technology tool to break through the Pareto frontier.The improved design of adaptive high-speed bogies is based on the whole vehicle stability analysis chart to lead the optimization of bogie parameters.According to the energy absorption mechanism of anti hunting（wide）frequency band,dynamic design and software analysis method,the analysis diagram of vehicle stability state is used to seek advantages and avoid disadvantages,and a hunting or other similar phenomenon is completely eliminated.In order to make the anti roll torsion bar play its normal function and resist the strong fluid structure coupling effect caused by unstable crosswind or wake disturbance,the sufficient safety and stability margin should be taken into account for the self stability of wheelset and the effectiveness of turning resistance moment.According to the particularity of China’s railway,two technical transformation schemes of adaptive fast/high-speed bogies are formulated according to the above methods,which are helpful to form uniform wear of wheel tread,and then the uniform,stable and rapid wear laws can be realized by using the change of safety and stability margin.