Nonlinear impact of traction rod on the dynamics of a high-speed rail vehicle carbody

Journal of Mechanical Science and Technology - This paper focuses on the bogie-carbody nonlinear dynamic interaction of a Shinkansen high-speed rail vehicle. The Euler-Bernoulli beam model is used...     

Influence of active steering with adaptive control law on a metro rail vehicle wheel wear and dynamic performance

Journal of Mechanical Science and Technology - An active steering bogie is designed to for yaw control of the wheel-sets to align the wheels with the track direction during curve negotiation....     

垂向减振器对铁道车辆动力学性能的影响分析

随着运行速度的不断提高,减振器在保持铁道车辆运行的安全性和乘坐的舒适性方面也发挥了越来越大的作用。在常规的动力学分析中,基本上只是考虑减振器的阻尼特性,忽略了减振器的端部连接刚度和卸荷特性等因素。在建立了充分考虑减振器的端部连接刚度、阻尼以及卸荷特性的减振器模型的基础上,结合铁道车辆的垂向简化模型,通过线性分析的方法研究了一系、二系垂向减振器的各参数对车体的频率响应和垂向平稳性的影响。并指出在进行减振器参数的选择和进行减振器相关的分析时,在阻尼特性的基础上还应增加对端部连接刚度和卸荷特性的关注。     

Fatigue life analysis of wheels on guideway vehicle using multibody dynamics

A guideway vehicle is used in automobile, semiconductor and LCD manufacturing industries to transport products efficiently. Since the operating speed of the guideway vehicle should be increased for maximum productivity, the weight of the vehicle has to be reduced, and this weight reduction may cause a failure of a part in the system. Therefore, the estimation of the fatigue life of the parts becomes an important problem. In this study, the fatigue life of the wheels in the guideway vehicle is estimated using an S-N curve. To obtain the fatigue life of a part, the S-N curve, the dynamic stress time history applied to the part, and the material property of the part are required. The S-N curve of the driving wheel is obtained from the fatigue experiment on wheels. To obtain the material properties of the driving wheel, which is composed of aluminum with urethane coating, the result of a compression hardware test and static analysis of the wheel’s FE model are used. The dynamic stress time history influencing the driving wheel can be obtained from linear superposition of the dynamic load time history and the static stress. The dynamic load time history is estimated by multibody dynamic analysis, and the static stress is obtained by finite element analysis.     

客车座椅造型快速设计研究

为应对产品多样化、瞬变性的市场需求,缩短设计周期和提高设计成功率,通过对快速设计理论中模块化技术的研究,以客车乘客座椅造型设计为例,结合用户需求、人机尺寸、产品结构、色彩及材质等设计约束条件的分析,提出了基于同一产品平台的系列产品快速造型设计方法,并给出了相关的造型设计案例,为提升产品造型设计效率,提高企业设计开发质量提供参考和借鉴.     

Effect of passenger car curving on rail corrugation at a curved track

The paper presents a corrugation calculation model, which considers Kalker's non-Hertzian rolling contact theory to be modified, a material wear model and a vertical and lateral coupling dynamics of a half passenger car and a curved track. The dynamics characters of the curved track model in frequency domain were investigated by the commercial finite element code ANSYS, and some results concerning rail corrugation are presented in this paper. During a passenger car passing a curved track the dynamical performance of the vehicle and track and the initiation and growth of the curved rail corrugation are analyzed with the present corrugation calculation model. In the numerical calculation, two track states are investigated. One is that the track does not have any congenital defect except for the discrete rail support by sleepers. The other is that the track has a lateral dent on the gauge corner of the high rail. The rail corrugations analyzed are attributed to the material wear mechanism. The numerical results obtained indicate that (1) a high passing frequency corrugation initiates on the smooth running surface of the curved rail during the first passing of the passenger car through the curved track without defects; (2) the initial corrugation develops quickly and its passing frequencies change with an increase of passenger car passage; (3) the interaction of the leading wheelset of the bogie and the curved rails causes more severe corrugation and wear on the rail running surface than that of the trailing wheelset of the same bogie; (4) discrete rail support by sleepers is the congenital defect leading to rail corrugation formation.     

Analysis of temperature distributions in surface grinding with intermittent wheels

An analytical model was established to calculate the curve of temperature distributions in surface grinding with intermittent wheels. In order to predict the numbers of the pulses imposed on the fluctuating temperature profile, a new quantity, the dynamic number of wheel segments in the grinding zone, was defined. The temperatures at the grinding zone were measured by using a foil thermocouple. It is found that the new quantity, the dynamic number of wheel segments, can be used to accurately predict the pulses on the measured temperature curves in the grinding zone. Through matching the calculated temperature curves with the measured results, it is found that the temperature profile is greatly dependent on the wheel segment-engaging states even at identical grinding parameters. However, the wheel segment-engaging states have little influence on the values of peak and valley temperatures.     

卸船机垂直臂架破坏事故分析

1 概述 双带式卸船机具有结构简单、能耗低、噪声小、无粉尘飞扬、效率高等优点,从80年代中期开始进入我国各大港口,主要用于粮食等散料的卸船.广州新沙港1999年引进了800TPH SIMPORTER 卸船机,使用不久便发生了垂直臂架破坏事故.如图1所示,前翼缘板在离顶部大约3 m处发生翘曲变形;后翼缘在离顶部2 m左右处和底部与给料头连接处发生变形;腹杆与翼缘连接处的角钢全部发生变形,部分出现断裂;前翼缘与给料头的连接处开裂40mm长.     

新型独立转向架的研制及其在改善轮轨关系方面的应用

从轮轨接触的形式、轮轨磨损成因及降低轮轨磨耗的对策分析出发,通过对独立旋转车轮工矿车辆转向架的研制和运行验证后,对该转向架的优点做了总结,结果表明该转向架在降低轮轨磨耗、提高曲线通过能力、提高适应线路扭曲的能力、改善车辆运行品质等方面均有明显效果,这对铁路干线车辆转向架具有借鉴意义。     

Theoretical cross-wind speed against rail vehicle derailment considering the cross-running wind of trains and the dynamic wheel-rail effects

In this paper, a theoretical formula was proposed that predicts the derailment index due to a cross wind applied to a rail vehicle considering the cross running wind condition of two running trains as well as the dynamic wheel-rail effects. The recently developed derailment theory on a wheelset was applied to this new cross wind derailment formula. Contrary to the conventional formulas, this new derailment formula was derived considering a dynamic derailment coefficient (Q/P) under normal running, the friction coefficient between the wheel and the rail, the wheel load variation, the cross running wind effects, and the cross wind. Using this proposed formula, the derailment pattern and the critical cross wind speed of derailment could be predicted for various cross running wind conditions of two running trains. Finally, for some typical examples, the results of this proposed formula were compared and verified with those of the conventional formulas and the numerical simulation of multi-body dynamics software, Recurdyn.     

基于模拟生产线的轨道车辆生产工艺优选研究

为满足轨道车辆优选生产工艺路线的需求,基于轨道车辆模拟生产线提出生产工艺的选优方法。以模拟生产线仿真车辆产品质量信息和相应的工艺参数为数据源,采用非参数分析方法对各种不同生产工艺路线进行优选,详细阐述工艺费用、设备负荷率、质量指数与损失率等工艺路线关键性能指标的计算过程,并给出简化的评价模型。采用非参数统计思想,通过二维列联表的独立性检验实现工艺路线和工艺性能的相关性分析,通过Wilcoxon秩和检验方法,实现工艺路线的选优求解。实例研究表明,该方法能够从产品质量数据和工艺参数得到统计推断性结论,可选取较优的生产工艺路线,控制车辆产品工艺费用,提高轨道车辆生产效率与产品质量。     

城轨不锈钢车辆门角激光-MAG复合焊工艺研究

介绍了城轨车辆不锈钢车体门角激光-MAG复合焊工艺的初步研究过程及成果。通过选用不同的焊接工艺参数规范对车体门角进行激光-MAG复合焊焊接,对焊接接头进行相关性能检测,选定出适合该焊接接头的激光-MAG复合焊工艺参数及焊接顺序,对焊接过程中出现的气孔及未焊透等焊接缺陷进行了原因分析,制定出车体门角进行激光-MAG复合焊焊接工艺。     

整车碰撞仿真及试验分析

采用1s-dyna等有限元软件,通过模拟小客车的正碰过程.讨论小客车碰撞有限元模型的建立方法.通过对变形情况、加速度时间历程曲线以及车各部分在碰撞中吸收能量的分析,评估小客车的耐撞性,结合试验数据,分析正碰建模方法的正确性,同时提出小客车的改进设计方案.     

乘用车车身结构件被动安全性试验台的研制

试验台不仅能够测试汽车车身的强度、刚度以及抗撞性能,还可用于相当广泛的其他零部件的试验.试验台不但能测试侧门强度,实时计算并显示平均力、最大力和被测汽车所吸收的能量,而且采用图像测量法精确测量车身刚度,以评价汽车安全性,为研发提供可靠详细的依据.     

BP neural network classification on passenger vehicle type based on GA of feature selection

万方数据知识服务平台-中外学术论文、中外标准、中外专利、科技成果、政策法规等科技文献的在线服务平台。     

城轨不锈钢车辆鼓型侧墙弧焊工艺研究

介绍了城轨不锈钢车辆鼓型侧墙弧焊工艺的研究过程及成果。通过选用合适的焊接工艺对城轨不锈钢车辆侧墙进行焊接,很好地控制了不锈钢车辆侧墙变形程度,选定出了适合该侧墙焊接的工艺方法,制定出了不锈钢车辆鼓型侧墙弧焊工艺。     

基于有向加权网的轨道车辆生产工艺路线优化研究

为解决城市轨道车辆生产线存在的生产效率不高与稳定性差等问题,提出了一种基于有向加权网络的城市轨道车辆工艺路线优化方法。该方法首先利用有向加权网络理论构建车辆生产线的生产网络模型,然后以生产线可靠性与制造成本为目标,建立轨道车辆工艺路线的多目标优化模型,并基于粒子群算法得到最优工艺路线生成算法,最后以某轨道列车生产线为例进行了验证,结果表明,该方法能显著降低生产线的生产成本,提高生产线的生产效率与稳定性。     

纺纱锭子动态特性的研究

用近代非线性动力学理论分析了纺纱锭子的动态特性。用数值方法得到转子系统在某些参数区域内的轴心轨迹图、Poincare映射图和分岔图等。讨论了系统各种形式的倍周期、拟周期和混沌运动。分析结果为定性地改善转子系统的稳定运行状态,提供了理论依据。     

Estimation of vehicle sideslip angle based on steering torque

Vehicle sideslip angle is one of the important indicators to determine whether vehicles are stable and is also a significant parameter for vehicle stability control. However, it is almost impossible to be measured directly without complex and expensive sensors or devices. Soft measurements are therefore generally adopted to estimate vehicle sideslip angle on the basis of easily observed physical quantities. This paper proposes an estimation method of sideslip angle based on steering torque instead of steering angle, for the fact that steering torque signal has more rapid and direct response compared with that obtained from steering angle. The frequency is analyzed between steering torque-sideslip angle and steering angle-sideslip angle transfer functions, and the extended Kalman filter (EKF) for vehicle sideslip angle based on steering torque is proposed. Both simulation results and vehicle tests prove the validity of our estimating method, indicating that the proposed method based on steering torque exhibits better accuracy and more rapid response in extreme region than the one based on steering angle.