列车脱轨机理与脱轨分析理论研究

在分析国内外脱轨研究现状的基础上，总结出脱轨研究中存在如下主要问题。（1）现有预防脱轨标准对实际列车脱轨没有控制作用。（2）不明原因列车脱轨机理不明确。（3）列车脱轨计算存在3个根本问题：①列车-轨道（桥梁）时变系统振动方程组的建立与求解未满足轮轨位移衔接条件；②仅以轨道横向不平顺作为列车-轨道（桥梁）时变系统横向振动的激振源，未考虑根本激振源——轮轨接触状态的影响；③仅以轨道不平顺的随机性和按时不变系统随机振动分析理论，     

国外反水雷技术装备的发展

本文介绍了国外最新研制和在研的一些新型反水雷技术装备，其中主要包括美国、英国、德国等国的一些新型反水雷技术装备。文章指出，发展无人水下航行器和一次性灭雷武器是今后反水雷装备研制的发展方向。     

国外反水雷舰艇装备现状及发展趋势

本文简述了发展反水雷舰艇装备的必要性,分析了国外主要国家的反水雷舰艇装备现状及发展趋势.     

矿用汽车市场及变速箱产品开发研究

通过对不同矿用汽车性能的比较、中国矿运输市场市场容量的分析以及各种矿用汽车在市场上的使用情况,说明矿用汽车这一卡车的细分市场市场潜力十分巨大,但它不同于一般的运输卡车,需要汽车厂家针对其特点为其配套专业的零部件产品,如变速箱等,来满足其特殊的使用要求,从而满足其使用性能,最终使其能够高效地为社会建设发展做出贡献。     

Stability enhancement of a high-speed train bogie using active mass inertial actuators

In this study, a method regarding frame lateral vibration control based on the state feedback of an additional oscillator is proposed, so as to improve the bogie hunting stability. The multi-objective optimisation method (MOOP), with two objective functions of the stability index and control effort, is solved by the NSGA-II algorithm to obtain the feedback gains. The frame lateral vibration control can effectively improve the bogie hunting stability according to the linear and non-linear analysis of a high-speed train bogie, in which a fault of the yaw damper and time delay in the control system are considered. The effect of the oscillator suspension parameters and time delay on the system stability and robustness are analysed. The results show that the damped vibration frequency of the oscillator should be equal to the bogie hunting frequency, but a harder oscillator suspension can be used to improve the hunting critical speed margin of the bogie control system. However, just as how the feeding the frame states back directly, a hard oscillator suspension will lead to instability in the control system at a certain time delay. Therefore, the improvement of bogie hunting stability and reduction of control system stability must be considered when optimising the oscillator parameters. For the 350?km/h train bogie covered in this study, the optimal mass, natural frequency and damping ratio of the additional oscillator are acquired.     

Actuator optimal placement studies of high-speed power bogie for active hunting stability

ABSTRACT

We put forward three actuator placements of the high-speed train power bogie to improve the train hunting stability. The active control forces act on the frame, between the frame and the motor, and on the motor by the inertial or retractable actuator, respectively, based on the feedback states of vibration velocity of the front and rear end beams. The feedback gains and the motor suspension parameters in different cases are optimised with the two objectives of system stability margin and control effort. The required actuator outputs of the three cases are compared based on the theoretical analysis with a 8 DOF bogie model. The results show that the three control cases can effectively improve the hunting stability, especially at high speed. The active control of motor lateral movement is helpful to increase the dynamic vibration absorbing function of the motor flexible suspension, and the control output is obviously smaller than the other two control cases. In addition, the influence of system delay on stability was analysed and we could use or avoid the effects of delay on the stability.     

现代轨道交通车辆的空气弹簧悬挂技术

介绍空气弹簧系统的构成、作用原理和技术发展。根据空气弹簧特性对转向架进行了分类。指出高柔性空气弹簧是无摇枕转向架二系悬挂装置的关键技术，其横向性能对车辆运行的平稳性有决定性的作用，并对蛇行运动稳定性有重要影响。提出了高柔性空气弹簧的改进和研制方向。     

列车在道岔中的运行稳定性分析

考虑道岔结构引起的竖向与横向不平顺以及轮轨接触关系的变化,将道岔区内轮轨系统空间耦合振动分析模型进一步完善。该模型用以模拟列车经过道岔时的蛇行运动,并分析了列车的平稳性与安全性。     

地下管线检测技术在管线检漏中的应用

地下管线由于腐蚀、意外损伤等因素引起泄漏,现场的复杂性使得检测工作十分困难,管线泄漏能否得到及时修复取决于检测的精度和准确度。文中介绍了地下管线定位技术、外防腐层检测技术和泄漏检测技术的原理,并对这一系列检测技术进行整合,制定了合理的检测工艺,通过运用和改进,取得了良好的效果,使泄漏管线得到及时的修复。该系列检测技术可以准确、快速地确定管线的泄漏点,明显提高检修效率。     

基于轮轨线性相互作用假定的车桥相互作用理论及应用

研究车桥耦合系统中轮轨相互作用关系问题。以刚体动力学方法建立车辆子系统模型,有限元法建立桥梁子系统模型;假定车辆轮对与钢轨之间在竖向上服从轮轨密贴假定,在横向上服从Kalker蠕滑理论;并在计算横向蠕滑力时考虑轮对锥形踏面和恒定法向力;以轨道不平顺为系统激励;建立车辆-桥梁统一的线性动力平衡方程组。利用上述轮轨线性相互作用假定,以SS8单节机车通过单跨32m简支梁为例,计算各轮对横向运动的时域及频域响应;讨论轮对蛇形运动波长、波幅的影响因素;分析桥梁横向振动、横向轨道不平顺以及车辆系统横向振动三者的关系;并验证轮对蛇行波假定的正确性。