基于边界层和复势理论的轮胎磨损颗粒物运动轨迹研究

Trajectory of tire wear particles based on boundary layer and complex potential theory

轮胎磨损颗粒物对生态环境和生物体健康都有非常严重的负面影响,辨识其发散路径并进行捕集已成为当前环境保护的重要课题之一.本文在极坐标下使用边界层和复势理论建立了轮胎磨损颗粒物的二维散射模型,计算了颗粒物的散射路径并进行了实验验证,进一步通过正交试验得到了各种因素对磨损颗粒物覆盖件碰撞高度的影响程度.结果表明:磨损颗粒物碰撞高度在很大程度上取决于其在边界层内的运动时间,粒径为2.5~5μm的轮胎磨损颗粒物的散射高度受车速变化影响不大.粒径5~15μm的轮胎磨损颗粒物与覆盖件发生碰撞的高度随着车速的提高先增大后减小,转折车速随颗粒物粒径的增大而减小.影响磨损颗粒物与覆盖件碰撞高度的因素主次顺序是:车速、车轮半径、接地印迹半长度、胎面与覆盖件的距离.

Tire wear particles have serious impact on the ecological environment and human health and how to capture and deal with the particulates has become an important issue to protect the environment. In this paper, the boundary layer and the complex potential theory are used to establish the two-dimensional scattering model of tire wear particles in polar coordinates. The scattering path of the particles is calculated and verified by experiments. Furthermore, the influence of various factors on the collision height between the wear particles and wheel cover is obtained through orthogonal test. The results show that the collision height between the wear particles and the wheel cover is largely determined by the time in the boundary layer. The scattering height of the tire wear particles with diameter from 2.5 to 5 μm is not greatly affected by the vehicle speed variation. The height of collisions of the tire wear particles with diameter from 5 to 15 μm increases first and then decreases with the increasing of the vehicle speed, and the turning speed of the vehicle decreases as the particle size increases. Finally, the order of the factors influencing the collision height between the wear particles and the wheel cover is obtained through orthogonal test as: the vehicle speed, the wheel radius, the half-length of the contact length and the distance between the tread and the cover.