【作者】 蔡永周；

【导师】 臧孟炎；

【作者基本信息】 华南理工大学 ， 车辆工程， 2014， 博士

【摘要】 高速行驶的汽车一旦发生爆胎事故,会对乘员、货物、路人及邻近车辆安全形成很大的威胁,造成无法挽回的损失。近年来,随着我国高速公路的迅猛发展,行车速度越来越快,发生爆胎事故的概率也随之增大。爆胎事故巨大的破坏性迫使许多学者和汽车企业对爆胎现象、爆胎后车辆的动力学特性及其对汽车操纵稳定性的影响与控制策略等进行深入研究。爆胎轮胎与正常轮胎有截然不同的运动学和动力学特性,进而影响到整车的运动。本文根据爆胎现象的物理效果开发了爆胎模拟实验装置和单轴爆胎实验台,实施单轮爆胎实验并获得爆胎过程轮胎胎压和轮辋下沉量随时间的变化曲线,使用非线性有限元软件LS-DYNA仿真分析爆胎现象以确认仿真模型的有效性,然后将这一爆胎模型应用于整车仿真分析,研究车辆行驶过程中爆胎现象发生后各个轮胎受力变化和车辆的运动响应,具体研究内容如下:首先,根据爆胎现象的物理效果,即胎压在短时间内迅速减小的特点,开发了简单可靠、可重复使用的爆胎发生模拟装置。这一装置由机械与控制部分构成,通过调节阀门开度大小可以控制爆胎的剧烈程度。爆胎模拟装置零部件完成加工和组装后进行气密性测试。其次,开发单轴爆胎实验台并实施单轮爆胎实验。为检验爆胎装置的效果,开发了由两个车轮构成的单轴爆胎实验台,在单轴上施加1／4车重后实施单轮爆胎实验,获取爆胎轮胎胎压和轮辋下沉量的时间历程。第三,建立单轴爆胎实验装置三维有限元模型,以单轴爆胎实验中获得的爆胎轮胎的胎压时间历程作为载荷条件施加于单个有限元轮胎内壁模拟单轴爆胎现象,获得爆胎过程轮辋下沉量随时间的变化曲线,通过与实验结果对比验证有限元模型的有效性。最后,建立包括转向系统、悬架系统、行驶系统的简化整车有限元模型,将爆胎模型(胎压变化曲线)作用于整车右前轮和右后轮,实施整车行驶过程中转向系统处于自由状态下的爆胎现象仿真分析。研究前后轮分别爆胎不同的整车响应和各车轮受力情况的变化。综上所述,本文的研究工作,为开展爆胎现象研究提供了新的方法和思路,为爆胎现象及安全对策研究提供了重要基础。更多还原

【Abstract】 Once the tire blow-out accident of a high-speed car occurs, it may push the threat topassengers, cargo, passers-by and vehicles nearby, causing irreparable damage. In recentyears, as the highway has developed rapidly, the running speed of cars is becoming more andmore fast. Meanwhile, the probability of tire blow-out accident rises obviously. The hugedestructiveness of tire blow-out accident prompts scholars and automobile enterprise toconduct the thorough research on the phenomenon of tire blow-out, especially on thedynamics response of the vehicle and its effect on the stability of vehicle handling as well ascontrol strategies.The tire of blow-out has very different kinematics and dynamics characteristics frompneumatic tire, which has great influence on the movement of the vehicle. In this paper, thetyre blow-out device and the test bench of tyre blow-out are developed according to thephysics effects of tire blow-out phenomenon. The tyre blow-out experiments are implementedand the curves of the rim subsidence time history and the tire pressure time history during tireblow-out process are obtained. The tire blow-out phenomenon is simulated by using nonlinearfinite element analysis software LS-DYNA to confirm the validity of the simulation model.Then, the tire blow-out model is applied to vehicle simulation analysis. The change of all tireforces and the motion responses of the vehicle are researched after the tire blow-out of therunning vehicle happens. The works are summarized as followsFirstly, the simple, reliable and reusable tyre blow-out generator is developed accordingto the physics effects of tire blow-out phenomenon and the tire pressure decrease rapidly in ashort time. It consists of mechanical and control part. The intensity of tire blow-out can becontrolled by regulating valve opening size. The air tightness of tire blow-out generator istested after the components of tire blow-out generator are manufactured and assembled.Secondly, the test bench for tyre blow-out is developed and the tyre blow-outexperiments are implemented. To test the effect of tire blow-out device, the test bench of twowheels for tyre blow-out is developed. The tyre blow-out experiments are implemented after the1/4vehicle weight is loaded on the shaft. The curves of the rim subsidence time historyand the tire pressure time history during tire blow-out process are obtained.Thirdly, based on215/60R16radial tire, the3-dimensional finite element model of tireblow-out experimental device is established. The tire blow-out phenomenon is simulated byapplying the curve of pressure-time history which is obtained by the tyre blow-outexperiments to the wall of single finite element tyre model. The rim subsidence curve of tyreblow-out process which is used to compare with the experimental results and verify thevalidity of the finite element model is obtained.Finally, the simplified finite element model of the vehicle including steering system,suspension system and running system is established. The tire blow-out model (tire pressurechange curve) is applied to the right front wheel and the right rear wheel of the vehicle tosimulate and analyzed the tire blow-out phenomenon when the vehicle is in the runningprocess and the steering system is under a free state. The change of all tire forces and themotion responses of the vehicle are researched when the front and rear tire blow-out of therunning vehicle happens, respectively.According to the above, the research work provides a new approach and thought forinvestigation of tire blow-out phenomenon and lays a solid foundation for tire blow-outphenomenon and safety countermeasure research.更多还原