全表面车轮径向疲劳试验的数值仿真及疲劳寿命分析

为对钢制全表面车轮的径向疲劳寿命进行预测,本文中针对全表面车轮的径向疲劳试验工况建立了有限元分析模型,考虑了轮胎的试验气压对车轮的影响,且使试验中径向载荷的施加过程尽可能接近真实工况。加载变化的径向载荷后得到危险区域的位置并得到车轮危险节点的载荷历程,预测车轮在径向疲劳试验时的疲劳寿命。在国内率先使用ANSYS Workbench分析平台对车轮进行径向疲劳分析,为车轮的径向疲劳分析提供了一种快捷且可靠的分析方法。     

轮胎充气压力对摩托车车轮应力分布的影响

轮胎充气压力对摩托车车轮应力分布有一定的影响,利用I-DEAS软件对车轮在各种载荷下的应力分布情况进行分析,得出冲击试验分析模型可以不考虑充气压力、径向载荷试验分析模型必须考虑充气压力的结论,为深入进行冲击试验和径向载荷疲劳试验有限元分析做了准备。     

汽车车轮双轴疲劳试验仿真方法

介绍了一种车轮侧倾的汽车车轮双轴疲劳的有限元仿真方法。该方法对车轮施加完整序列的载荷谱,可以真实地反映车轮双轴疲劳载荷工况,实现缩短车轮研发周期,节约开发成本。     

基于ANSYS Workbench的赛车车轮疲劳仿真分析

赛车车轮是车辆承载的重要安全部件,行驶过程中,赛车车轮承受来自路面不同幅值、不同频率的激励除受垂直力外,还受因车辆起动、制动时扭矩的作用,转弯、冲击等来自多方向的不规则受力。高速旋转的车轮直接影响车辆的平稳性和操纵性。文章以Wonder7号铝合金车轮为研究对象,在CATIA中建立赛车车轮的三维模型,并导入到ANSYS Workbench软件中生成轮辋和轮辐的几何模型。根据计算极限工况下,对wonder7号车轮进行受力分析,并对车轮的受力载荷进行确定。建立车轮的有限元模型并进行有限元分析。为预测车轮的疲劳寿命,用Ansys中的Fatigue模块对车轮进行疲劳寿命分析,预测车轮疲劳破坏位置和使用寿命,对设计人员起了指导意义。     

基于ANSYS workbench的车轮疲劳强度分析

车轮是汽车上的重要部件,它承受车身的重力、驱动力、制动力以及汽车转弯时的横向载荷,对汽车的行驶安全性、稳定性和平顺性都有着非常重要的影响。采用有限元分析的方法可以在新产品设计初期分析出车轮的强度和疲劳寿命,大大缩短设计周期。本文以14×5.5J车轮为研究对象,采用三维建模软件pro/E对车轮进行建模,利用有限元分析软件ANsYs worl出ench对车轮弯曲疲劳强度试验进行模拟,得到车轮强度和疲劳寿命的分析结果。     

汽车车轮性能试验方法及标准

汽车车轮是汽车行驶系统中重要的安全部件，世界各国的标准均对其进行了严格的要求。汽车车轮的安全性能主要是通过弯曲疲劳试验、径向疲劳试验以及冲击试验来进行考核，但是在各种标准具体的试验方法上还是存在着一定差异。     

摩托车和轻便摩托车辐条式车轮标准简介

摩托车和轻便摩托车辐条式车轮标准从3个方面对辐条式车轮的技术要求及试验方法进行了编制:1)对车轮的基本要求;2)对轮毂辐条孔的极限拉力、辐条、条母组件的极限拉力、条母的拧紧力矩等限值作出了规定;3)辐条式车轮的4项性能要求。通过试验验证,径向冲击试验合格率为60%,径向载荷疲劳试验合格率为83.3%,扭转疲劳试验合格率为100%,证明标准是可行的。     

基于疲劳试验的车轮拓扑优化和多目标优化

基于动态弯曲疲劳试验和动态径向疲劳试验对16×61/2J型车轮的轮辐进行了联合拓扑优化,设计了一个带有镁合金轮辋和铝合金轮辐的组装式车轮结构。建立其弯曲疲劳试验和径向疲劳试验的有限元模型,计算其强度、刚度、疲劳寿命和径向疲劳寿命安全系数,并分析了这些性能与车轮结构之间的关系。利用网格变形技术建立了组装式车轮在两种工况下的参数化模型并定义了12个设计变量,使用Isight软件平台集成各性能指标的计算软件建立了车轮多目标优化模型,利用哈默斯雷和最优拉丁超立方试验设计分别提取了72和10个样本点,拟合了Kriging近似模型并检验了近似模型的精度。利用所建立的近似模型,以车轮质量最小、弯曲疲劳寿命和径向疲劳寿命安全系数最大为目标,应力、位移和柔度为约束,采用第二代非劣排序遗传算法(NSGA-Ⅱ)对车轮进行了多目标优化,得到了Pareto前沿,综合考虑了车轮各项性能,选取了一个妥协解作为优化结果,并对优化前后车轮综合性能进行了对比。结果表明,在满足车轮各项性能要求的条件下,优化得到组装式车轮的质量比同型铸造铝合金车轮减小了29.42%。     

汽车车轮的试验方法及试验结果分析

介绍了车轮弯曲疲劳、径向疲劳、弯曲刚度的试验方法,车轮易损部位应力测定方法和车轮弯曲疲劳曲线的绘制方法,并对试验结果进行了分析。     

车轮寿命试验方法的发展趋势

车轮是汽车底盘中重要的安全部件,需要用精确严格的试验来保证.文章介绍了车轮安全性的3大试验,即弯曲疲劳、径向疲劳和冲击试验,并利用不断进步的汽车试验理论和技术,对车轮进行寿命试验.目前内转鼓试验向外转鼓三向加载试验方面发展,外转鼓三向加载试验可更精确与合理地评价车轮寿命.得出运用典型路谱提取车轮试验载荷谱的寿命评价和考核方法正逐渐成为车轮试验的主流方向.     

The Wheel Shimmy Problem: Its Relationship to Wheel and Road Irregularities

The equations of motion are derived for a single wheel steerable pneumatic tire system. Included in this system are a built-in wheel wobble and wheel-tire irregularities which produce oscillation of the normal load. Special emphasis is placed on the dynamic characterization of the tire cornering force and aligning torque. The results show that the built-in wheel wobble causes a steady shimmy which is large when the wheel rotation frequency is close to the natural shimmy frequency. The results also show that a normal load oscillation which has a frequency approximately twice the natural shimmy frequency causes a decrease in shimmy stability.     

The Wheel Shimmy Problem: Its Relationship to Wheel and Road Irregularities

SUMMARY

The equations of motion are derived for a single wheel steerable pneumatic tire system. Included in this system are a built-in wheel wobble and wheel-tire irregularities which produce oscillation of the normal load. Special emphasis is placed on the dynamic characterization of the tire cornering force and aligning torque. The results show that the built-in wheel wobble causes a steady shimmy which is large when the wheel rotation frequency is close to the natural shimmy frequency. The results also show that a normal load oscillation which has a frequency approximately twice the natural shimmy frequency causes a decrease in shimmy stability.     

Automotive Stability and Handling Dynamics in Cornering and Braking Maneuvers

SUMMARY

Automotive steering behaviour is classified for steady-state cornering and the definitions of over-/understeer and stability/instability are well known. In this paper it is intended to apply these definitions to combined cornering and braking maneuvers i.e. to extend the criteria to quasi-steady-state conditions. This way of investigation was chosen because it gives a clear idea of the typical handling behaviour. Furthermore, the vehicle behaviour is analyzed using the cornering stiffness of the axles and front/rear cornering stiffness ratio because this is always of primary significance. The following contribution is based on a theoretical analysis considering the most important non-linear vehicle properties.

The paper deals with two groups of vehicles: single vehicles (passenger cars) and combinations (passenger car/caravan and tractor/semitrailer). In the case of combinations the effect of trailers on the towing vehicles is examined. So, careful attention is paid to the coupling forces, which alter the wheel loads and influence steerability and stability.     

轮胎非稳态转向特性非线性仿真模型

本文以轮与路面之间的滑移速度为出发点，在稳态指数统一模型的基础上，建立了轮胎非稳态转向特性非线性仿真模型。在实验研究中，发现了动态过程回正力臂和附加的回正力矩的滞后特性。仿真和试验结果对比表明，该模型足以反映轮胎非线性转向特性，可用于前轮及汽车操纵动力学仿真方面的研究。     

Dynamics of Pneumatic Tire Vehicles with Connected Suspension Systems

A vehicle model, with 10 degrees of freedom is used to investigate the skidding conditions of any wheel of the vehicle in motion. Equations for the load transfer and equations for the pneumatic tire spring and shock absorber are derived. Parameters such as gradual cornering, U-curve cornering, the wavy road surface of different wave lengths and cases of independent and connected suspension systems are inputs to the system. The tire calculated forces and their corresponding maximum resistance forces are the outputs of the systems. A connected suspension system is found to resist skidding better than the independent suspension system. The system is non-linear, and numerical solutions are obtained.     

Modelling the effects of friction modifiers on rail corrugation in cornering

A proposed solution to the problem of rail corrugation on curves of urban lines is the use of friction modifiers. Recent experimental research indicates this approach can be effective. This paper makes use of two theoretical models to study the effects of friction modifiers on corrugation in cornering. The first one is a nonlinear time-domain model that predicts corrugation growth from a series of simulated passes of a bogie. The second one is a frequency domain model of wheel–rail interaction, linearised about a steady cornering state, estimated from the nonlinear model. Both models predict reduction of growth of corrugation due to the use of friction modifiers. Friction modifiers can alter the steady cornering state to one with somewhat lower creeps and much lower tractions. Major reductions in corrugation growth rate have been shown to occur if a wheel can be prevented from reaching a state of full sliding when subject to oscillating creeps caused by existing rail corrugation.     

Wheel Slip Control in Traction Control System for Vehicle Stability

Traction control systems are used to prevent wheel slippage and to maximize traction forces. This paper proposes a new scheme to enhance vehicle lateral stability with a traction control system during cornering and lane changes. This scheme controls wheel slip during cornering by varying the slip ratio as a function of the slip angle. It assumes that a traction control system with the engine throttle angle is used. The scheme is dynamically simulated with a model of front-wheel-driven passenger vehicles. Simulation results show that the proposed scheme is robust and superior to a conventional one, which is based upon fixed slip ratios, during cornering and lane changes.     

Wheel Slip Control in Traction Control System for Vehicle Stability

Traction control systems are used to prevent wheel slippage and to maximize traction forces. This paper proposes a new scheme to enhance vehicle lateral stability with a traction control system during cornering and lane changes. This scheme controls wheel slip during cornering by varying the slip ratio as a function of the slip angle. It assumes that a traction control system with the engine throttle angle is used. The scheme is dynamically simulated with a model of front-wheel-driven passenger vehicles. Simulation results show that the proposed scheme is robust and superior to a conventional one, which is based upon fixed slip ratios, during cornering and lane changes.     

Dynamics of Pneumatic Tire Vehicles with Connected Suspension Systems

SUMMARY

A vehicle model, with 10 degrees of freedom is used to investigate the skidding conditions of any wheel of the vehicle in motion. Equations for the load transfer and equations for the pneumatic tire spring and shock absorber are derived. Parameters such as gradual cornering, U-curve cornering, the wavy road surface of different wave lengths and cases of independent and connected suspension systems are inputs to the system. The tire calculated forces and their corresponding maximum resistance forces are the outputs of the systems. A connected suspension system is found to resist skidding better than the independent suspension system. The system is non-linear, and numerical solutions are obtained.     

电动轮驱动电动汽车差速技术研究

提出了电动轮旋转动力学方程和对驱动电机采用转矩指令控制及车轮转速随动的方法,实现电动轮系统的自适应差速。进行了转向行驶、路面不平及不同车轮半径等工况的道路试验,试验结果表明:电动轮汽车在各种工况下都能保持良好的差速性能,具有自适应差速特性。