侧风下高速列车车体与轮对的运行姿态

应用流体动力学理论, 建立了高速列车空气动力学模型, 计算了作用于高速列车车体上的气动力和气动力矩; 应用多体动力学理论, 建立了车辆系统动力学模型, 分析了在不同风向角、侧偏角与合成风速下高速列车头车车体和轮对的运行姿态。计算结果表明: 在不同侧风环境下, 头车车体始终向背风侧横摆和侧滚; 当风向角为90°时, 车体的横向位移和侧滚角最大; 当列车车速为350 km.h^-1, 侧风风速分别为13.8、32.6 m.s^-1时, 列车头车车体最大横向位移分别为74.2、171.7 mm, 最大侧滚角分别为3.1°和8.4°; 当列车车速为200 km.h^-1, 风速不小于32.6 m.s^-1, 且风向角为90°时, 列车头车一、二位轮对均向背风侧横移, 背风侧车轮易发生爬轨现象, 三、四位轮对均向迎风侧横移, 三位轮对迎风侧车轮易发生爬轨现象; 四位轮对的横移量和摇头角均小于前三位轮对, 相对安全。     

70%低地板轻轨车辆的型式比较

阐述了低地板轻轨车辆的发展和70%低地板轻轨车辆的优点.介绍了70%低地板轻轨车辆的几种典型型式.从转向架和车体结构方面比较其各种型式的优缺点,指出模块化是低地板轻轨车辆的发展方向.实现低地板的关键技术在于解决独立车轮转向架中的轮缘磨耗问题.给出了提高独立车轮导向能力的措施.     

B型地铁车辆ZMC080型转向架统型轮对设计

文章主要介绍了ZMC080型转向架统型轮对的设计方案及计算、校核过程。校核结果表明,该统型轮对完全满足B型地铁车辆的使用要求。     

Estimation of wheel–rail contact conditions and adhesion using the multiple model approach

This paper presents the development of a multiple model estimation approach for the identification of the adhesion limit to overcome the problem of the wheel slip/slide at the rail wheel-rail contact. The contact characteristics at the rail wheel-rail interface are both highly nonlinear and subject to changes due to exposure to external contaminations. The detection of adhesion and its changes is therefore scientifically challenging, but would provide a critical information in the control of trains to avoid undesirable wear of the wheels/track but also the safety compromise of rail operations. This study exploits the variations in the dynamic behaviour of the railway wheelset caused by the contact condition changes and applies a bank of Kalman filters designed at selected operation points for the adhesion estimation. A fuzzy logic system is then developed to identify the contact conditions by examining the residuals from the Kalman filters.     

发动机瞬时角速度波动分析

发动机在一定稳定工况下运转，瞬时转速会呈现一定的波动现象。本文介绍一种以发动机瞬时角速度的实时检测为基础，在一个工作循环内按着火顺序将做功冲程中瞬时角速度波动作为评价依据的判定发动机工作状况的方法。     

Sensitivity analysis to assess the influence of the inertial properties of railway vehicle bodies on the vehicle's dynamic behaviour

A sensitivity analysis has been performed to assess the influence of the inertial properties of railway vehicles on their dynamic behaviour. To do this, 216 dynamic simulations were performed modifying, one at a time, the masses, moments of inertia and heights of the centre of gravity of the carbody, the bogie and the wheelset. Three values were assigned to each parameter, corresponding to the percentiles 10, 50 and 90 of a data set stored in a database of railway vehicles. After processing the results of these simulations, the analysed parameters were sorted by increasing influence. It was also found which of these parameters could be estimated with a lesser degree of accuracy for future simulations without appreciably affecting the simulation results. In general terms, it was concluded that the most sensitive inertial properties are the mass and the vertical moment of inertia, and the least sensitive ones the longitudinal and lateral moments of inertia.     

Research into the problem of wheel tread spalling caused by wheelset longitudinal vibration

This study mainly focuses on the mechanism of wheel tread spalling through wheelset longitudinal vibration that has been often neglected. Analysis of two actual cases of the wheel tread spalling problem leads to the conclusion that the wheel tread spalling is closely related to the wheelset longitudinal vibration in some locomotives, and many of these problems can be reasonably explained if the wheelset longitudinal vibration is considered. For better understanding of some abnormal wheel spalling problems, the formations of the wheelset longitudinal vibration and the wheel/rail contact parameters were analysed in the initial wheel tread spalling. With the preliminary analytical results, the wheelset longitudinal dynamic behaviour, the characteristics of wheel/rail contact and the mechanics in the condition of the wheelset longitudinal vibration were further studied quantitatively. The results showed that the wheelset longitudinal vibration changed not only the limit of these parameters and the position of principal stress, but also the direction of the principal stress on the surface of wheel/rail contact patch. It is likely that the significant stress changes provoke too much stress on the surface of wheel/rail contact patch, cause fatigue in wheel/rail contact patch and eventually lead to wheel tread spalling. The results of these studies suggest that the suppression of the wheelset longitudinal vibration extends wheel/rail life and the addition of a vertical damper with an ahead angle provides a possible solution to the wheel spalling problem.     

城市轻轨车辆及其相关技术的发展

从轻轨车辆总体结构、走行部及电传动等方面详细介绍了城市轻轨车辆的发展情况,其中包括低地板、独立旋转车轮和变流器等技术。同时介绍当前国外城市轻轨车辆的主要应用模式,分析未来城市轻轨车辆的发展趋势。     

高职院校单招生教学管理问题的思考

本文为了探讨高职院校单招生教学管理问题,从单招生源的结构、自身特点以及对其施教难点进行了分析,进而提出了教学措施上的一点改良思考。作为新兴的单招方式虽然存在一些问题,但却是高职院校招生改革的一个新尝试。本文的目的就是希望该文能对单招生的教学管理工作起到一点有益的作用。     

动车组不落轮镟床工序记录系统的设计

在动车组专项修中,处理CRH动车组轮对踏面擦伤与剥离的主要设备是动车组不落轮镟床,动车组不落轮镟床的正确操作关系着镟修作业的顺利完成.记录下操作人员每步操作,对严格落实设备操作规程,规范各项操作,实现标准化作业有着重要意义.本系统就是本着这一目的而设计,而且也为动车组镟修作业工序卡控的实现奠定了基础.