速度400 km/h轮对初始旋转惯性对滚动接触有限元模型的影响  

Effect of Initial Rotational Inertia of Wheels on Wheel-rail Rolling Contact Finite Element Model at 400 km/h

作　　者：徐凡 何远鹏 冀怡名 圣小珍 肖新标[1] XU Fan;HE Yuanpeng;JI Yiming;SHENG Xiaozhen;XIAO Xinbiao(State Key Laboratory of Traction Power,Southwest Jiaotong University,Chengdu 610036,China;School of Urban Railway Transportation,Shanghai University of Engineering Science,Shanghai 201620,China)

机构地区：[1]西南交通大学牵引动力国家重点实验室,四川成都610036 [2]上海工程技术大学城市轨道交通学院,上海201620

出　　处：《铁道学报》2023年第7期126-133,共8页Journal of the China Railway Society

基　　金：国家自然科学基金(U1834201,U1934203,52002340)。

摘　　要：基于显式动力学有限元方法所建立的三维轮轨滚动接触模型是研究高速铁路轮轨相互作用的有效工具。该模型既考虑轮轨的真实几何形状(包括不平顺)和材料非线性,又详细考虑轮轨间的几何接触关系和轮轨系统的纵向动力学性能,得到广泛的应用。在具体实现模型仿真时,采用隐式-显式相结合的办法。传统的做法是,隐式计算时不考虑车轮的旋转,只考虑重力作用下的静态位移场,然后将得到的静态结果作为显式计算的初始条件,同时对车轮施加前进速度和转动角速度以及转矩等条件,求解轮轨的相互作用。大量文献表明,用这种做法来启动显式动力学求解,会产生剧烈的初始瞬态响应,导致求解时间过长,甚至不收敛,尤其在速度高达400 km/h时。基于此,对上述模型进行了改进,在进行隐式计算时,首先考虑车轮的旋转,得到车轮在离心力作用下的位移,在此基础上再考虑车轮受重力作用与钢轨发生接触,得到接触斑、法向接触应力以及车轮的应力应变等,然后将更新后的结果作为显式计算的初始条件进行显式动力学求解。算例表明:改进后的模型可大大减小初始瞬态响应,减少有限元节点和网格数,从而加快计算的收敛过程,提高计算效率;轮轨力频谱存在无衰减频带,在该频带内轮轨力随着模型长度的增加几乎不衰减,传统方法难以通过增加求解区的方式得到稳态轮轨力。The 3D high-speed wheel-rail rolling contact model based on the explicit dynamic finite element method is an effective tool to study the wheel-rail interaction of high-speed railways.The model,not only taking into account the real geometry(including irregularities)and material nonlinearity,but also geometric contact relationship between wheel and rail and the longitudinal dynamic performance of the wheel-rail system,has been widely used.In the implementation of model simulation,the method of implicit-explicit combination was used.Under the traditional method,during implicit calculation,only the static displacement field under the action of gravity,rather than the rotation of the wheel,was considered.Then the obtained static results were used as the initial conditions for explicit calculation.At the same time,the conditions such as the forward velocity,rotational angular velocity and torque were applied to the wheel to solve the wheel-rail interaction.A large number of literature shows that the use of this method to initiate explicit dynamic solutions can result in severe initial transient responses,causing too long solution time and even non-convergence,especially at speed up to 400 km/h.Based on this,the above model was improved in this paper.During implicit calculation,the rotation of the wheels should be first considered to obtain the displacement and stress of the wheel under the action of centrifugal force.On this basis,the wheels came into contact with the rail under the action of gravity,resulting in the contact spot,the normal contact stress and stress strain of the wheel.Then,the updated results were used as the initial conditions for explicit calculation for explicit dynamic solution.Numerical examples show that the improved model can greatly reduce the initial transient response and the number of finite element nodes and grids,thus speeding up the convergence process and further improving the calculation efficiency.A non attenuation frequency band exists in the wheel-rail force spectrum,in which the wh

关 键 词：隐式-显式有限元法 三维滚动接触模型 轮轨相互作用 速度400 km/h 

分 类 号：U211.5[交通运输工程—道路与铁道工程]