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论文建立了汽车动力性检测模型,并对损耗功率分量进行了研究,最终实现快速检测汽车动力性,对汽车技术状况进行等级评定。 相似文献
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分析了目前用于汽车动力性检测的底盘测功机,由于其基本结构参数的不同,检测工况控制精度的差异,检测重复性不佳及其内阻功率损耗的差异等因素,严重影响了汽车动力性检测结果的一致性,进而提出用于汽车动力性检测的底盘测功机必须进行型式认证。 相似文献
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本文简述了我国在用汽车动力性进行了评价的现状及必要性,首次提出了驱动比功率RDP作为在用汽车动力性的技术评价参数,同时应用汽车功率平衡理论,确定了在用汽车动力性上路运行驱动比功率的新限值,并组织了217辆客、货车验证了可行性,可分析检证资料的基础上,提出了有关建议。 相似文献
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在建立汽车动力性与燃料经济性模拟计算方法的基础上,提出了应用模糊数学方法描述汽车动力性限制的约束条件,以汽车多工况燃料经济性为目标函数,优化了汽车的传动系数,从而使整车燃料经济性获得改善。 相似文献
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汽车动力性设计方法研究 总被引:1,自引:0,他引:1
提出汽车动力性指标应作进一步约束,规范并加以分类的概念。评述了汽车特性,发动机特性和地面特性参数在汽车动力性设计中的作用。重点介绍了与分析了发动机特性参数与曲线的特点及使用。 相似文献
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Kai Wei Feng Wang Ping Wang Zi-xuan Liu Pan Zhang 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(3):351-370
The soft under baseplate pad of WJ-8 rail fastener frequently used in China’s high-speed railways was taken as the study subject, and a laboratory test was performed to measure its temperature and frequency-dependent dynamic performance at 0.3?Hz and at ?60°C to 20°C with intervals of 2.5°C. Its higher frequency-dependent results at different temperatures were then further predicted based on the time–temperature superposition (TTS) and Williams–Landel–Ferry (WLF) formula. The fractional derivative Kelvin–Voigt (FDKV) model was used to represent the temperature- and frequency-dependent dynamic properties of the tested rail pad. By means of the FDKV model for rail pads and vehicle–track coupled dynamic theory, high-speed vehicle–track coupled vibrations due to temperature- and frequency-dependent dynamic properties of rail pads was investigated. Finally, further combining with the measured frequency-dependent dynamic performance of vehicle’s rubber primary suspension, the high-speed vehicle–track coupled vibration responses were discussed. It is found that the storage stiffness and loss factor of the tested rail pad are sensitive to low temperatures or high frequencies. The proposed FDKV model for the frequency-dependent storage stiffness and loss factors of the tested rail pad can basically meet the fitting precision, especially at ordinary temperatures. The numerical simulation results indicate that the vertical vibration levels of high-speed vehicle–track coupled systems calculated with the FDKV model for rail pads in time domain are higher than those calculated with the ordinary Kelvin–Voigt (KV) model for rail pads. Additionally, the temperature- and frequency-dependent dynamic properties of the tested rail pads would alter the vertical vibration acceleration levels (VALs) of the car body and bogie in 1/3 octave frequencies above 31.5?Hz, especially enlarge the vertical VALs of the wheel set and rail in 1/3 octave frequencies of 31.5–100?Hz and above 315?Hz, which are the dominant frequencies of ground vibration acceleration and rolling noise (or bridge noise) caused by high-speed railways respectively. Since the fractional derivative value of the adopted rubber primary suspension, unlike the tested rail pad, is very close to 1, its frequency-dependent dynamic performance has little effect on high-speed vehicle–track coupled vibration responses. 相似文献
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为提高白车身轻量化设计效率,提出了一种试验设计与PSI决策相结合的轻量化设计策略。首先对白车身基本静-动态性能和正撞安全性能进行有限元分析,并通过车辆正撞试验验证有限元模型的准确性。然后采用贡献度分析对白车身前端结构进行设计变量筛选。接着通过试验设计获得白车身前端结构轻量化备选解。最后采用PSI法对众多备选解进行多目标决策,获得最佳轻量化方案。结果表明,轻量化设计后,白车身前端结构质量减轻4.43 kg,轻量化率达7.23%,同时白车身性能均满足设计基线要求。 相似文献
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车辆动力学性能开发包括性能目标设定、目标分解、优化设计、底盘调校,逐渐向目标达成逼近,开发结束后实现目标达成。性能目标分解即指标分解,用简单有物理意义的理论公式关联整车指标与总成指标,将整车的客观性能指标分解至系统特性,是整车性能目标达成的关键环节,在性能开发中承上启下,是各主机厂的核心技术。性能指标分解正常在车辆开发初期,用于指标分解的模型应采用尽可能少的建模参数,建模分析迅速且模型能明确表达系统参数对整车性能的影响规律。ADAMS或CarSim模型,由于模型结构过于复杂,不适用于车辆性能的指标分解。本文建立了用于性能指标分解的模型,并基于此模型研究底盘动力学操稳转向性能指标的分解及应用方法,为车辆动力学性能开发工作提供理论指导。 相似文献
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Static and Dynamic Performance of Permanent Magnet Suspension for Maglev Transport Vehicle 总被引:1,自引:0,他引:1
Hitoshi Tsunashima Masato Abe 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1998,29(2):83-111
The design and performance of a mechanical air gap controller for a maglev transport vehicle are described. The basic requirement for a functional design of the controller is derived first and its effectiveness is shown by experiments. After the construction of dynamic vehicle models dynamic characteristics of the maglev vehicle are introduced and the stability criteria for magnetic levitation are derived. The effect of a dead zone in the mechanical air gap controller and nonlinear characteristics of the magnets, which are expected to exert a large influence on vehicle levitation performance, are investigated by simulations. The simulation results show that a low control lever ratio causes sudden deterioration of the levitation performance if there exists a dead zone in the controller, and a suitable control lever ratio which is unaffected by the dead zone is proposed. Finally, field test results with an actual maglev transport vehicle are shown and the dynamic levitation performance of the vehicle is discussed. 相似文献
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矿区环境复杂,电传动矿用汽车的轮边电机传动系统对整车动力性、制动性及平顺性有极大影响,为了综合路面激励和电机自身激励综合分析驱动系统动态特性,采用数值仿真软件建立轮边电机传动系统模型,分析其在启动加速、平稳运行及制动时的动态特性,为了验证模型的准确性进行了实车实验。结果表明该轮边电机传动系统的输出转矩发生考虑波动转矩后会较大影响整车加速和制动性能,常见车速的加速和减速性能会减弱5%,稳定行驶阶段差别不大。刚柔耦合模型能更准确地描述驱动系统及整车动力特性,对整车的设计有指导意义。 相似文献
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汽车的动力性和燃油经济性是其最基本与最重要的性能之一。为在汽车开发之初分析整车的动力性和燃油经济性,文章研究了动力性和燃油经济性的评价指标,合理选取整车参数,利用GTDRIVE软件对整车进行动力学和运动学建模与仿真计算。将仿真结果与试验结果对比,合理设置边界条件修正模型,最终得到较为精准的模型,使得在没有样车阶段,利用GT—DRIVE软件仿真可以得到整车的动力性和燃油经济性参数,能够对动力系统的匹配方案进行定量评价,为以后汽车的动力系统匹配优化提供一定的理论参考。 相似文献
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Yao Shan Bettina Albers Shunhua Zhou Stavros A. Savidis 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(1):23-40
The variation of the rail support stiffness is an inherent issue of railway tracks. There is still no consensus on the influence of the rail support stiffness variation on the dynamic response of the vehicle–track system. One view indicates that changes of the support stiffness do not have considerable influence on the vehicle dynamic response. The main influence factor is the rail deflection. However, the opposite view presents that the influence of the support stiffness on the system dynamic response is obvious. Reasons that lead to the dispute of previous studies are the neglect of the influence of the excitation frequencies and a lack of understanding of stiffness sensitive zones. In this study a vehicle–track coupling model with equivalent overall support stiffness is employed to investigate the response of the vehicle to changes of the track stiffness and excitation frequencies. Results show that for each of frequencies (1–40?Hz) the dynamic response of the vehicle is only sensitive to a certain range of the support stiffness. A stiffness sensitive zone for each excitation frequency can be observed. In order to further study the influence of the subgrade on the vehicle system dynamic response a vehicle–track-subgrade model is utilised. The subgrade stiffness belonging to the stiffness sensitive zone has a significant influence on vehicle vibrations. For overall support stiffness of the rail higher than 20?kN/mm, the stiffness sensitive zones of low excitation frequencies can be avoided. 相似文献