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排序方式: 共有1497条查询结果,搜索用时 16 毫秒
91.
Yang Chen Yunbo Hou Andrew Peterson 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2019,57(4):617-635
Failure mode and effects analysis are performed for a dual levelling valve pneumatic suspension to determine the effect of suspension failure on tractor–semi-trailer dynamics, using a detailed model of suspension pneumatics coupled with a truck dynamic model. A key element of failure analysis in suspensions with one or two levelling valves is determining the effect on the vehicle body roll when one or more failures occur. The failure modes considered are mainly the suspension pneumatic components, including clogged levelling valve, bent control rod, disabled lever arm, and punctured or leaking connectors and pipes. The pneumatic suspension is modelled in AMESim, with critical parameters established through component testing. Upon validating the AMESim component model experimentally, the pneumatic suspension model is integrated into TruckSim for studying the consequences of suspension failure on truck dynamics. The simulation results indicate that the second levelling valve in a dual-valve arrangement brings a certain amount of failure redundancy to the system, in the sense that when one side fails, the other side can compensate for the failure. Equipping the trailer with dual levelling valves brings an additional stabilising effect to the vehicle in the event of tractor suspension failure. 相似文献
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93.
研究车辆在怠速工况下的发动机舱热空气回流问题,基于OpenFOAM 软件进行回流计算方法的开发。通过设置监控面及组分转换面来重新定义格栅新空气和舱内回流热空气等组分,可直接计算出回流在监控面上的分布及回流率和回流量。根据开发的方法对某款插电式混合动力汽车(Plug-in Hybrid Electric Vehicle,PHEV)车型进行计算并提出不同的优化方案,使其发动机舱回流率从32.7% 分别降低至24.0%和9.3%,回流量从0.169 kg/s分别降低至0.128 kg/s和0.048 kg/s,从而降低了冷凝器等散热器的进风温度,提高了怠速工况下热管理系统的性能。 相似文献
94.
低动力作用货车转向架动力性能的研究 总被引:2,自引:0,他引:2
沈志云 《西南交通大学学报》1991,(1)
本文探讨低动力作用货车转向架的原理及其动力性能的计算和评估方法。首先定义9项指标,作为衡量车辆对轨道动力作用的标准。然后研究这些指标的诸因素。在此基础上总结出实现低动力作用的基本途径。本文还应用这些研究成果,提出4种低动力作用货车转向架的设计方案,并通过数值计算,同国内、外主型货车转向架对比,从而论证其在我国铁路采用的可行性。 相似文献
95.
Shin Hyung Rhee Boris P. Makarov H. Krishinan Vladimir Ivanov 《Journal of Marine Science and Technology》2005,10(4):173-180
This study was concerned with the free-surface wave flow around a surface-piercing foil. The volume of fluid method implemented
in a Navier–Stokes computational fluid dynamics code was employed. Three widely used discretization schemes for the volume
of fluid method were assessed for a test case that involved general ship waves, spilling breaking waves in front of the leading
edge, and bubbly free surfaces in separated regions. A single computational approach was selected for the comparison, and
a grid-dependence study was carried out. The computational results were validated against existing experimental data, showing
good agreement. The validation results suggest that all three discretization schemes perform well, but the best and most efficient
results were obtained using the high-resolution interface capturing scheme. 相似文献
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98.
《铁道标准设计通讯》2016,(1):83-86
由于部分山区桥梁跨越发育冲沟,会受到泥石流的冲击作用,基于桥梁构件能力保护原则,对泥石流作用下桥梁动力响应分析的研究就显得尤为重要。应用有限元动态接触方法对碰撞过程进行数值模拟,选取某高速公路30 m实心T墩建立三维实体有限元模型,分析其在泥石流作用下的动力响应情况。研究表明,在泥石流冲击作用下,块石与桥墩接触区及下部构件连接处应力较大,墩顶位移随上部荷载压力增大而不断减小,即设计应考虑分别提高桥墩的承载能力及其构件连接处的变形能力。 相似文献
99.
Gábor Orosz 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2016,54(8):1147-1176
Connected vehicle systems (CVS) are considered in this paper where vehicles exchange information using wireless vehicle-to-vehicle (V2V) communication. The concept of connected cruise control (CCC) is established that allows control design at the level of individual vehicles while exploiting V2V connectivity. Due to its high level of modularity the proposed design can be applied to large heterogeneous traffic systems. The dynamics of a simple CVS is analysed in detail while taking into account nonlinearities in the vehicle dynamics as well as in the controller. Time delays that arise due to intermittencies and packet drops in the communication channels are also incorporated. The results are summarised using stability charts which allow one to select control gains to maintain stability and ensure disturbance attenuation when the delay is below a critical value. 相似文献
100.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(9):803-829
In this paper, we examine the lateral dynamics emulation capabilities of an automotive vehicle equipped with four-wheel steering. We first demonstrate that the lateral dynamics of a wide range of vehicles can be emulated, either with little or with no modification on the test vehicle. Then we discuss a sliding mode controller for active front and rear wheel steering, in order to track some given yaw rate and side-slip angle. Analytically, it is shown that the proposed controller is robust to plant parameter variations by±10%, and is invariant to unmeasurable wind disturbance. The performance of the sliding mode controller is evaluated via computer simulations to verify its robustness to vehicle parameter variations and delay in the loop, and its insensitivity to wind disturbance. Finally, the emulation of a bus, a van, and two commercially available passenger vehicles is demonstrated in an advanced nonlinear simulator. 相似文献