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691.
高速机车车辆动力学模拟中的轮轨接触模型 总被引:5,自引:1,他引:4
为解决铁路实现高速化后严重加剧的车辆和线路状态恶化问题,必须从加强车辆—轨道系统动力学的 研究着手。迄今所发展的传统滚动接触理论仅适用于低频车辆动力学,且仅限于小蠕滑的情况。为适应高频车 辆—轨道系统动力学和大蠕滑的驱动动力学研究的需要,必须研究发展新的轮轨滚动接触力学。本文在对传统 滚动接触理论的发展作简要评述后,主要介绍并讨论了近期为配合铁路实现高速化而发展起来的新轮轨滚动接 触理论:高频非稳态滚动接触,非Hertz接触,有限元法,宏观滑动区域的接触模型及钢轨疲劳损坏机理等方 面问题。这些问题对铁路实现高速化的意义都是非常重大的。 相似文献
692.
693.
首钢秘铁6 000 t/h装船机是用于老码头扩容改造项目的新设备.这台装船机总体设计的难点在于减轻自重及轮压控制,以满足老码头的轮压要求.该设备的研制成功,为类似的老码头的技术改造积累了经验. 相似文献
694.
纵向耦合独立旋转车轮转向架导向机理 总被引:1,自引:0,他引:1
从轮轨蠕滑力出发,研究了纵向耦合独立旋转车轮转向架的导向机理,通过建立独立旋转车轮转向架整车动力学模型,基于数值仿真方法,分析比较了采用纵向耦合独立旋转车轮转向架、横向耦合独立旋转车轮转向架与全独立旋转车轮转向架车辆的导向性能.计算结果表明:纵向耦合独立旋转车轮轮对具备直线上的对中性能和曲线上的导向性能;在曲线通过时,... 相似文献
695.
为了对具有简谐波形的钢轨短波波磨进行分组与分析轮轨非稳态滚动接触的纵向蠕滑力特性,引入了波磨深度指数与波长比,采用Kalker三维滚动接触理论计算了车轮的纵向蠕滑力,并与采用稳态滚动理论计算结果进行了对比,使用频率响应的系统辨识法对纵向蠕滑力的波动分量进行了拟合,在短波波磨等深度指数条件下,用波长比的二阶传递函数描述了... 相似文献
696.
该转向盘以嵌入式系统为核心,利用GPS数据变化判定车辆驻、行状态,以控制持续驾驶时间的计算周期,利用变压器式角位移传感器采集转向盘转角电压变化,采用电压波模式识别判断疲劳状态,并结合持续驾驶时间参量对疲劳驾驶进行预警。 相似文献
697.
698.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(11):991-1011
A robust nonparametric approach to vehicle stability control by means of a four-wheel steer by wire system is introduced. Both yaw rate and sideslip angle feedbacks are used in order to effectively take into account safety as well as handling performances. Reference courses for yaw rate and sideslip angle are computed on the basis of the vehicle speed and the handwheel angle imposed by the driver. An output multiplicative model set is used to describe the uncertainty arising from a wide range of vehicle operating situations. The effects of saturation of the control variables (i.e. front and rear steering angles) are taken into account by adopting enhanced internal model control methodologies in the design of the feedback controller. Actuator dynamics are considered in the controller design. Improvements on understeer characteristics, stability in demanding conditions such as turning on low friction surfaces, damping properties in impulsive manoeuvres, and improved handling in closed loop (i.e. with driver feedback) manoeuvres are shown through extensive simulation results performed on an accurate 14 degrees of freedom nonlinear model, which proved to give good modelling results as compared with collected experimental data. 相似文献
699.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(3):325-342
Dynamic performance, safety and maintenance costs of railway vehicles strongly depend on wheelset dynamics and particularly on the design of wheelset profile. This paper considers the effect of worn wheel profile on vehicle dynamics and the trend of wear in the wheels as a result of the vehicle movements. ADAMS/RAIL is used to build a multi-body system model of the vehicle. The track model is also configured as an elastic body. Measured new and worn wheel profiles are used to provide boundary conditions for the wheel/rail contacts. The fleet velocity profile taken during its normal braking is also used for the simulation. Wear numbers are calculated for different sets of wheels and the results compared with each other. Outcome of this research can be used for modifying dynamic performance of the vehicle, improving its suspension elements and increasing ride quality. It can also be further processed to reach to a modified wheel profile suitable for the fleet/track combination and for improved maintenance of the wheels. A major advantage of the computer models in this paper is the insertion of the wheel surface properties into the boundary conditions for dynamic modelling of the fleet. This is performed by regularly measuring the worn wheel profiles during their service life and by the calculation of the wear rate for individual wheels. 相似文献
700.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(10):1115-1133
A practical method to determine the zone of two contact points and the transfer of wheel–rail forces between two rails in a turnout is presented in this paper. The method is based on a wheel–rail elastic penetration assumption and used to study a turnout system for a 200 km/h high-speed railway in China. Rail profiles in a number of key sections in the turnout are identified first, and profiles in other sections are then obtained by interpolation between key sections. The track is modelled as flexible with rails and sleepers represented by beams and the interaction between the vehicle and turnout is simulated for cases of the vehicle passing the turnout. Results are mainly presented for two-point contact positions and the characteristics of the wheel–rail forces transference. It is found that the heights of the switch and crossing rail top have significant effects on the wheel–rail contact forces. Finally, the optimised top height for the crossing rails is proposed to reduce the system dynamic force in the turnout system. 相似文献