车轮与高速道岔翼轨的接触分析

为合理设计道岔,更好地匹配轮对和道岔型面,用有限元法求解车轮与高速道岔翼轨的接触问题.建立4种不同型面车轮与高速道岔翼轨接触的有限元模型,分析车轮通过高速道岔翼轨的轮岔接触斑和等效应力的变化规律,计算结果表明:机车车轮与翼轨的接触斑位于翼轨轨顸外侧,动车车轮与翼轨接触的接触斑位置在翼轨轨顶中部;磨耗后JM3型面车轮与翼轨接触时,容易出现应力集中,尤其是在距离心轨尖端50 cm位置处;磨耗后JM3型面车轮与翼轨接触产生的等效应力最大.     

地铁线路扣件刚度对钢轨振动与波磨的影响

为探明整体道床轨道区段波磨发生机理及其对轮轨系统参数的影响规律,建立轮对和整体道床轨道三维有限元模型,分析轮轨共振模态与整体道床钢轨振动特性,探讨钢轨扣件刚度和轮对振动模态对整体道床区段钢轨波磨的影响规律.结果 表明:钢轨扣件刚度主要影响钢轨起跳共振频率,而对钢轨pinned-pinned共振频率影响甚微;较低的扣件刚...     

钢轨火焰热处理温度场数值模拟

为在钢轨火焰热处理时使钢轨接头达到规定的温度和合理均匀分布的温度场,在Abaqus中建立PD3钢轨的三维有限元模型,通过调整加热火焰模型的热流密度,模拟钢轨的温度场,获得钢轨异形结构对钢轨温度场的影响规律.结果表明：在采用均匀热流密度加热火焰模型时,钢轨底部升温速度最快,钢轨头部最慢;加热完成后钢轨底部平均温度最高,钢轨头部最低,钢轨温度场分布均匀性较差,而对于钢轨心部,钢轨腰部升温速度最快、平均温度最高,钢轨头部升温速度最慢、平均温度最低.经过对加热火焰模型热流密度的优化,钢轨表面和心部温度场分布的均匀性得到很好改善,可为实际生产中火焰热处理设计提供参考.     

A mesoscopic simulation modelling methodology for analyzing and evaluating freight train operations in a rail network

This paper includes a mesoscopic simulation modelling methodology developed for analysing and evaluating freight train operations in a rail network. The product of this methodology is a simulation rail network model implemented using an event-based simulation computer package called SIMUL 8. For simulation modelling purposes a decomposition approach is used. This approach allows us to separate the rail network under study into its components such as rail lines, rail yards, rail stations, rail terminals and junctions. The components of the rail network are thought of as interconnected queuing systems that interact and influence one another, so that the global impact of freight train operations in a rail network is captured.The products presented in this paper are of interest to rail freight tactical management, where global benefits are pursued.     

Rail Detection Based on LSD and the Least Square Curve Fitting

It is necessary to rely on the rail gauge to determine whether the object beside the track will affect train operation safety or not. A convenient and fast method based on line segment detector (LSD) and the least square curve fitting to identify the rail in the image is proposed in this paper. The image in front of the train can be obtained through the camera on-board. After preprocessing, it will be divided equally along the longitudinal axis. Utilizing the characteristics of the LSD algorithm, the edges are approximated into multiple line segments. After screening the terminals of the line segments, it can generate the mathematical model of the rail in the image based on the least square. Experiments show that the algorithm in this paper can fit the rail curve accurately and has good applicability and robustness.

     

柔性轮对结构振动对车辆动力学性能的影响

为研究轮对柔性对车辆动力学的影响,建立高速列车轮对的有限元模型,对轮对进行自由模态分析.通过模态综合法获取柔性轮对模态信息,应用多体系统动力学理论建立柔性轮对-刚性轨道接触力学模型;建立包含高速旋转柔性轮对的车辆-轨道耦合动力学模型,研究高速列车在直线和曲线通过时轮对结构振动对车辆动力学性能的影响.结果表明:轮对的结构振动对轮轨接触点位置、蠕滑率、蠕滑力和脱轨因数等均产生较明显的影响,但是对轮重减载率影响较小,因此应采用更加精确的柔性轮轨耦合模型研究轮轨相互作用、轮轨滚动接触疲劳和轮轨噪声等.     

柴油机共轨压力模糊自适应PID控制研究

柴油机高压共轨燃油系统中,共轨压力决定了燃油喷射压力,共轨压力随不同工况的调节能力及其压力的稳定性从根本上影响着系统性能。针对共轨压力控制,设计了模糊PID控制器,增加了积分分离与轨压预控制技术,给出了共轨压力的控制策略和实现方法。通过对PID参数的在线自适应整定,实现了在不同柴油机工况下对不同共轨压力变化的最佳控制。台架实验结果表明,共轨压力随柴油机转速与单次喷油量的增加应相应提高;当柴油机转速较高时,PID控制器应采用较大的控制参数;轨压预控制可有效地减少轨压波动和缩短轨压稳定时间;提出的控制策略和实现方法可把轨压控制偏差稳定在1.7%以下。     

基于Gocator视觉传感器的轨头参数计算

轮轨间紧密接触使轨头轮廓产生不规则变化,传统钢轨检测方法主要测量钢轨的垂直磨耗和水平磨耗,不能全面反映钢轨横截面的轮廓信息。基于Gocator视觉传感器采集、拼接得到的完整轨头轮廓数据及标准钢轨轨头轮廓曲线解析式,提出计算轨头剩余面积、轨头45°角磨耗和轨头角度参数的计算方法。该方法通过传感器拼接得到的离散点数据,采用优化分段三次的拟合方法进行多项式拟合,依次对多项式积分得到整个轨头剩余面积;通过轨头45°角所在直线与测量轮廓的交点计算其磨耗;通过计算轨头圆弧相交点处切线斜率得到轨头角度。实验数据表明,在钢轨同一截面计算得到的参数误差小,精度高,计算速度快,这些参数的有效测量值为钢轨自动化打磨维护提供指导意义。     

城市轨道交通联调联试的组织与实施

联调联试作为城市轨道交通建设中的一个重要环节,是一项涉及多系统、多任务、技术难度大的系统工程,其组织与实施应遵循科学、安全和有序的原则进行。以南京宁和城际轨道交通一期工程为例,介绍城市轨道交通联调联试的整体流程,包括联调联试的筹划、组织与实施以及收尾,重点对联调联试的接口识别与分析进行阐述,并在此基础上创新性地提出以通信、信号、综合监控、供电四个专业横向牵头,其他专业纵向配合的调试模式,形成纵横交错的矩阵式调试组织结构,有效发挥系统优势,提高联调联试效率,为城市轨道交通联调联试的开展提供有益建议。     

Railway multibody simulation with the knife-edge-equivalent wheel–rail constraint equations

This paper describes a new numerical procedure for the modelling and simulation of the wheel–rail contact in railway dynamic simulations. The method is called knife-edge-equivalent contact constraint method, or simply KEC-method. Using this method, the wheel–rail contact is modelled as rigid or constraint-based using a set of kinematic constraints that eliminates one-degree of freedom of relative wheel–rail motion. The KEC-method uses a transformed but equivalent wheel profile in contact with a single-point rail. This equivalent profile has the property of producing the same wheelset-rail relative kinematics as the real wheel–rail profiles. The method can be used efficiently online while achieving better computational times than using contact lookup tables. Compared with existing constraint methods, the KEC-method has the following advantages: (1) simplification of the wheel–rail contact constraints, (2) simplified wheel–rail profiles, (3) online solution of the contact constraints, (4) reduction of the number of surface parameters, and (5) increased computational efficiency. A comparative study with respect to the use of efficient contact lookup tables in the simulation of Metro de Sevilla (metropolitan train in the city of Sevilla) shows that this contact method is appropriate to simulate the dynamics of a railway vehicle efficiently.

     

Urban Functional Spatial Succession Trajectory and Determination of Renewal Mode in Rail Transit Station Area——Multiple Cases Comparisons and Sustainable Enlightenment

At present, the layout of rail transportation is an important driving force for optimizing the spatial structure of cities and regions and will also accelerate urban space renewal. This paper uses inter-field interpretation of multi-source data information, combining the spatial judgment scheme, Based on the comprehensive perspective of “three-dimensional integration” scale characteristics, functional attributes and agglomeration patterns of urban functional space, finely depicted urban spatial succession trajectory and update model of the rail transportation station. The study found that: (1) urban space scale showed significant reduction in urban central area, high-density residential, commercial service site;(2) urban functional succession tends to dominate the update mode, especially the high-efficiency catering and entertainment, business service format is the main function;(3) urban function of the rail transit station space is agglomerated. Taking this as a reference, it is proposed that the urban spatial renewal of China's rail transit stations should be based on responding to the development requirements of the times and stimulating the spatial vibrancy of the station; corresponding to the station environment, rational allocation of functional elements; careful considerate functional agglomeration characteristics, optimize station space structure and update spatial succession framework strategy, in order to provide important inspiration and policy recommendations for China's successive access to the station space update and planning regulation of different rail transportation development stages.     

城市轨道交通网络特性与级联失效鲁棒性分析

为探讨城市轨道交通网络(U RT N)的网络特性及面对突发事件时的鲁棒性,提升运营效率,基于复杂网络理论,采用Space-L方法构建URTN拓扑结构,提出URTN站点重要性综合评价指标.建立URTN级联失效模型,设计级联失效仿真算法,通过网络效率和最大连通子图比例两项鲁棒性评价指标,定量分析不同攻击策略下U RT N级...     

A numerical method for prediction of curved rail wear

Important published papers on rail wear in the past were reviewed. A numerical method was put forward to predict curved rail wear during a railway vehicle curving. The numerical method was discussed in detail. It considered a combination of Kalker’s non-Hertzian rolling contact theory, rail material wear model, the coupling dynamics of the vehicle and track, and the three-dimensional contact geometry analysis of wheel-rail. In its numerical implementation, the dynamical parameters of all the parts of the vehicle and track, such as normal loads and creepages of the wheels and rails, were firstly obtained through the curving dynamics analysis. The wheel-rail contact geometry calculation gave the wheel-rail contact geometry parameters, which were used in the wheel-rail rolling contact calculation with Kalker’s non-Hertzian rolling contact theory modified. The friction work densities on the contact areas of the wheels and rails were obtained in the rolling contact calculation, and were used to predict the rail running surface wears caused by the multiple wheels of the vehicle simultaneously with the rail material wear model. In the rail material wear model, it was assumed that the mass loss of each unit area was proportional to the frictional work density in the contact area. A numerical example was present to verify the present method. The numerical results of the example are reasonable, and indicate that the high rail wear of the curved track caused by the leading wheelset is much more serious than those caused by the other three wheels of the same bogie.     

一种基于漏磁检测的钢轨伤损判定和计数方法

为了快速有效地评估轨顶表面损伤状态,提出一种基于漏磁(Magnetic Flux Leakage,MFL)检测的钢轨伤损判定和计数方法.该方法使用自适应阈值法计算判伤阈值,减小了噪声对判伤结果的影响,并用整段MFL数据的峰峰值进行预判伤;根据峰值点位置选定判伤窗口,缩短了数据处理时间,利用窗口内数据的峰峰值进行伤损判定...     

铁轨表面缺陷的视觉检测与识别算法

提出一种铁轨表面缺陷的视觉检测与识别算法。设计铁轨表面缺陷视觉检测与识别系统的总体结构,基于水平投影法提取铁轨表面区域,采用逻辑操作组合检测结果,使用 BP 神经网络进行缺陷分类。实验结果表明,该算法能准确地检测与识别铁轨表面的疤痕和波纹擦伤这2种缺陷,分类正确率分别达到99%和95%。     

Investigations into the skills of modern and traditional train driving

Rail operations are housed inside a complex and extremely dynamic system where work is distributed in time and space. The train driver has traditionally relied on their own decisions, plans, and actions to navigate the rail environment, but the use of modern driver systems that force how these activities are regulated has altered this dynamic. This paper reports the findings of a study that set out to investigate the skills of modern (enhanced display-based) and traditional (real world) train driving. Data were collected from a variety of UK domain experts (n = 45) using an innovative methodology that converged multiple techniques for knowledge elicitation and analysis. The findings are represented in a model of dynamic train control and discussed according to the specific features and nature of tracking skill in the rail domain. The utility of the model is demonstrated through work of its application to the design of a train simulator and research tool for systematic study of rail human factor issues.     

基于深度学习的城市轨道客流预测实训基地培训系统设计与实现

为进行城市轨道客流量的科学预测,设计实现了实训基地培训系统,在系统中分别构建BP(Back Propagation)神经网络模型与DBN(Deep Belief Network)深度置信网络模型来进行城市轨道客流量数据的收集与整理。针对城市轨道交通车流量短时间快速增长的问题,在系统中建立实时数据分析处理模块,结合深度置信网络,使用算法对轨道客流进行实时准确的预测。将采集到的大量数据通过系统的数据处理模块进行分析验证,数据分析结果显示：在深度置信网络模型中,轨道交通各节点平均均方根误差相比BP神经网络模型大约减少了0.01475,每批次任务实时计算时间平均为3.5s,系统预测实时性较好,准确率较高,有很好的预测效果,可以合理地规划城市轨道交通线路,有效提高了城市轨道的交通利用率。     

燃油分配管结构强度仿真

采用仿真与试验相结合的方法分析燃油分配管的结构强度.讨论模态分析及频率响应分析相关理论和燃油分配管的建模特点.采用Abaqus对燃油分配管实例进行数值模拟,分析燃油分配管仿真建模中网格划分、算法选择和阻尼参数等关键问题.仿真和试验结果表明:燃油分配管的1阶频率为320.22 Hz,频率响应分析的最大应力为330 MPa,说明结构存在风险;支架板加厚1.5mm后燃油分配管的1阶频率为524.00 Hz,同时,试验得到1阶频率为512 Hz,两者相对误差为2.3％,说明结构通过扫频试验.     

基于傅里叶变换轮廓术的钢轨三维面型复原

随着现代化轨道交通的飞速发展,在线非接触式检测技术已成为钢轨面型检测的趋势.本文基于傅里叶变换轮廓术（FTP）提出实现钢轨的三维面型复原的新方法.通过生成虚拟光栅,再将其投影在被测钢轨上,得到被测钢轨的变形光场图.再由滤波和相位展开等步骤成功恢复出被测钢轨的三维面型,为控制钢轨的外形尺寸,提高外观质量提供了新的方法.     

区域控制器的安全需求建模与自动验证

轨道交通区域控制器（ZC）是我国轨道交通信号系统选型的主流制式——基于通信的列车控制系统（CBTC）的核心子系统，其突出的安全性使得安全需求的形式化验证成为一个非常重要的问题.但是ZC自身的复杂性以及领域知识的繁杂难以掌握，使得形式化方法很难应用到安全需求的验证中去.针对这些问题，提出一种安全需求的自动验证方法，使用半形式化的问题框架方法（PF）来建模和分解安全需求，根据需求模型自动生成安全需求的验证模型和验证性质，在此基础上自动生成验证模型的Scade语言实现，并通过Design Verifier验证器对需求进行组合验证.最后，使用了某个实际案例ZC的一个子问题CAL_EOA进行了研究，实验结果证明了该方法的可行性与有效性，它能自动地将安全需求模型进行组合验证，改善了验证的效率.