Simplified Analysis of Steady-State Turning Behaviour of Motor Vehicles Part 2: Stability of the Steady-State Turn∗

SUMMARY

A finite element model suitable for camber thrust analysis is formed. By inclining and pressing this finite element model onto the road plane, the forces prevailing in the contact patch of an inclined standing tire are calculated and the asymmetry-dependent mechanism of camber thrust generation is analyzed. By rotating the inclined standing tire at a constant vertical deflection, the roll-distance-dependent mechanism of camber thrust generation is analyzed.     

A Finite Element Model for Analysis of Deformations of Bias-Ply Motorcycle Tires Subject to Inflation Pressure

The finite element model previously formulated to represent a bias-ply motorcycle tire is improved for more accurate orthotropic stiffness values. Efforts are centered on accurate mapping of the cord angle from an actual tire to the finite element model. Using this improved finite element model, the deformations of the bias-ply motorcycle tire subject to inflation pressure are analyzed.     

虚拟试车场动力学轮胎模型技术研究

以P205/55R16轮胎为对象,建立了虚拟试车场动力学轮胎模型,进行了轮胎径向刚度、扭转特性和侧偏特性的仿真分析。通过与相同工况下的轮胎试验台架测试结果对比可知,所建立的虚拟试车场动力学轮胎模型有效,可以满足虚拟试车场仿真需要。     

轮胎泵气噪声有限元仿真分析

轮胎花纹槽泵气噪声是轮胎噪声的主要部分之一。在假设轮胎胎面结构与空气完全耦合的条件下建立轮胎横向花纹槽噪声的有限元模型,在施加与速度相关的强制位移条件下对空气中花纹槽泵气噪声进行仿真仿真,验证轮胎花纹槽泵气噪声的机理,同时通过线性迭加轮胎周向单个横向花纹槽的方法,给出轮胎花纹槽整体噪声的频域曲线。     

悬架导向机构硬点灵敏度分析及多目标优化设计

采用有限转动张量,结合矢量代数法,建立了悬架导向机构的运动学数学模型,并对硬点作灵敏度分析.从提高操纵稳定性和降低轮胎磨损的角度出发,采用微型多目标遗传算法,对悬架跳动中轮心处侧向滑移量、车轮外倾角和前束角进行优化.结果表明,仪通过一次优化就能得到满足不同偏好的悬架硬点坐标.     

Two-Dimensional Contact Area of a Pneumatic Tire Subjected to a Lateral Force

A mathematical model of a two-dimensional contact patch of pneumatic tires rolling over a rigid flat road surface at arbitrary slip and camber angles has been developed. The model is simple in concept, contains few parameters and is applicable to any tire simulation models. In addition to tire geometric parameters and vertical deflection, the carcass camber angle is introduced in the model. This angle is alone responsible for the asymmetric shape of the tire contact patch when the tire undergoes a lateral force. The computed contact patches agree well with the measured patches of an automotive tire at different slip and camber angles. Lastly, the influence of the contact patch geometry on the tire cornering and aligning properties has been discussed through a computational example. It has been shown that the effect of tire contact patch geometry on the steady state behavior is rather remarkable.     

实心橡胶轮胎温度场有限元分析

根据高速履带车辆实心橡胶轮胎的工作条件,在合理假设基础上建立了轮胎热分析有限元模型。借助大型有限元分析软件ANSYS,对某型实心橡胶轮胎温度场的计算,得到了轮胎内部温度场的分布情况,并讨论了轮胎厚度、轮胎宽度、车速、载荷等参数对轮胎温升特性的影响。     

车轮外倾角与前束值的设计匹配

车轮外倾角与车轮前束值是车轮定位中的两个重要参数,车轮前束是为了抵消车轮外倾产生的侧滑不利影响,因此前束值要与车轮的外倾角有合理的匹配。综合考虑车辆的结构参数和轮胎特性,基于车轮的侧滑机理,推导出车轮外倾角与前束值的合理匹配关系模型,用试验结果验证了模型的正确性,为在车辆的设计开发过程中,合理的确定车轮的外倾角与前束值提供理论参考。     

非均布移动荷载下含表面裂缝路面结构应力响应

采用移动加载的动载模型,考虑轮胎花纹形式,选用非均布轮胎荷载模式,建立三维有限元路面结构模型分析了非均布移动荷载作用下含表面纵向和横向裂缝路面结构的应力响应,以探求移动荷载作用下表面裂缝的开裂机理.采用空间有限元——时间差分法对问题进行数值求解.分析过程中对裂缝尖端网格局部进行加密处理,并用位移法求取裂缝尖端的应力强度...     

Prediction procedure for wear distribution of transient rolling tire

As a research method, finite element analysis (FEA) with ABAQUS can help researchers to study throughout the whole process of abnormal tire wear. For precise tread wear simulation, this paper introduces a tire finite element model building method. Then, the model is verified by comparing its simulation results with experiment data. Based on the verified model, tire high-speed rolling procedure is presented by combining steady-state transport analysis and dynamic analysis. To predict the wear distribution, micro tread wear calculation method is described. Finally, the wear prediction procedure of tread mesh evolving is introduced and tire polygonal wear pattern is simulated by this procedure.     

高速滚动汽车轮胎稳态温度场分布的数值研究

建立了滚动轮胎热平衡状态下的简化传热数学模型。应用自行开发的传热和热弹性力学分析有限元软件对中型载货车用9．OO一20(12P．R)尼龙斜交胎进行了稳态温度场仿真计算，获得了胎体内部的稳态温度场分布。分析了轮眙的速度、几何结构参数及材料特性参数对轮胎最高温升的影响，通过回归分析建立了该轮胎速度与最高温升的经验计算公式。     

钢底板-波形钢腹板连续刚构桥悬臂拼装异步施工线形控制技术研究

钢底板-波形钢腹板连续刚构桥悬臂拼装异步施工过程复杂，线形控制难度较大。通过数值分析与现场监测相结合的方式，建立有限元计算模型，讨论了剪切变形、相对湿度等因素对主梁挠度的影响，进一步优化预拱度，同时结合监测数据进行分析，结果表明：剪切变形对主梁挠度的影响较大，对于波形钢腹板刚构桥，其挠度计算不能忽略该部分的影响；在进行预拱度设置时，应重视环境相对湿度的影响；通过对主梁各工况变形的监测，主梁实际变形规律与理论基本相符，主梁合龙后线形平顺。     

徐变模式对连续梁桥预拱度计算的影响分析

混凝土徐变是混凝土连续梁桥预拱度计算的一项主要内容,该文从徐变模式出发.综合比较了国内公路新旧桥规徐变模式的差异,以某高速公路上的一座大跨连续梁桥为项目背景建立有限元模型,对不同徐变模式下的顶拱度计算结果进行对比,得到了一些结论具有一定的工程借鉴意义.     

轮胎动力学特性仿真分析研究

分析了各种常用轮胎模型的特点与应用范围,根据汽车操纵动力学研究的需求,在Matlab环境下运用魔术公式建立了轮胎动力学模型,并对汽车轮胎力与纵向滑移率,纵向力、侧向力及回正力矩与纵向滑移率、侧偏角、外倾角、垂直载荷的关系等轮胎特性进行了仿真分析,实验结果表明,魔术公式轮胎动力学模型可以较好地模拟轮胎的动力学特性,适用于车辆动力学研究领域。     

斜腹板宽箱梁桥全桥实体仿真分析

应用土木专用非线性及细部分析软件Midas FEA建立一联3×35m斜腹板宽箱梁桥的实体有限元分析模型,并根据实际施工顺序及成桥状态对全桥进行各施工阶段和成桥状态的仿真分析,为此类桥梁的设计和施工积累经验。     

Prediction of tire natural frequency with consideration of the enveloping property

A lumped tire model was developed with consideration of the enveloping property in order to predict the natural tire frequency. Tire stiffness was classified into vertical, sidewall, and enveloping stiffnesses, and the tire characteristics were analyzed in detail experimentally and via finite element analysis. In addition, the effective masses of the tire tread and belt were extracted directly from design specifications taking into account the sizes and material properties of different rubber blocks. Using the design parameters of the tires, natural frequencies were calculated from the derived model and were compared with experimental results. Finally, based on good agreement with experimental results, sensitivity analysis was performed to verify the effect of tire stiffnesses on the natural frequencies.     

Dynamic Properties of Motorcycle and Scooter Tires: Measurement and Comparison

Summary Results of an experimental research program dealing with motorcycle and scooter tires are presented. Experimental tests were carried out by means of a rotating disk test machine, which is particularly suited to test tires in the presence of large camber angles. First, the capabilities of the rotating disk machine are discussed and results are compared with the ones obtained by means of other test machines. Then the properties of several motorcycle and scooter tires are presented and compared. The advantage of presenting results in terms of camber and sideslip stiffness is highlighted. The effect of tire working conditions (inflation pressure, load and temperature) is analyzed. Finally the measurement of tire torques is discussed and some results dealing with self-aligning, twisting and rolling resistance torques are presented.     

某车型上推力杆结构改进

重型汽车上推力杆在使用过程中杆头发生断裂失效比例较大,经过对售后件分析及安装位置分析建立受力分析模型,进行有限元计算,并根据有限元分析结果进行优化设计。针对优化后推力杆经行拉伸、扭摆、偏转等疲劳试验,及装车路试表明优化后推力杆可满足该车型的使用强度。     

双横臂独立悬架的前轮主销内倾角算法研究

针对前桥为双横臂独立悬架汽车，基于轮胎侧偏特性和计及外倾角的影响，建立前轮转向后回正力矩数学模型，根据转向轮回正力矩与回正阻力力矩平衡方程式，推导其前轮主销内倾角的算法。用样车做实例计算与试验，验证其正确性，为前轮定位参数中主销内倾角的设计提供理论参考。     

Dynamic Properties of Motorcycle and Scooter Tires: Measurement and Comparison

Summary Results of an experimental research program dealing with motorcycle and scooter tires are presented. Experimental tests were carried out by means of a rotating disk test machine, which is particularly suited to test tires in the presence of large camber angles. First, the capabilities of the rotating disk machine are discussed and results are compared with the ones obtained by means of other test machines. Then the properties of several motorcycle and scooter tires are presented and compared. The advantage of presenting results in terms of camber and sideslip stiffness is highlighted. The effect of tire working conditions (inflation pressure, load and temperature) is analyzed. Finally the measurement of tire torques is discussed and some results dealing with self-aligning, twisting and rolling resistance torques are presented.