弯道复合工况下走行轮胎偏磨损数值分析
Numerical analysis of running tire uneven wear under curved complex condition

针对弯道工况下，跨座式单轨车辆走行轮胎偏磨损严重，造成车辆运营成本增大，并影响单轨车辆行驶安全性的现象，建立了轮轨接触有限元模型，并对比走行轮胎3个方向刚度的试验值和仿真值验证了模型的有效性。采用单轨车辆动力学仿真模型来获得弯道复合工况参数，采用数值方法分析了弯道复合工况下走行轮胎相对滑移量、接地压力2个接地状态量，并采用摩擦功总和及摩擦功偏度值评价走行轮胎磨损和偏磨损，研究走行轮胎的摩擦功分布规律、摩擦功总和及摩擦功偏度。研究结果表明：走行轮胎相对滑移量较大值出现在前左和前右胎肩部位，且纵向节点相对滑移量平均值沿横向呈两端大、中间小的分布规律；走行轮胎接地压力在纵向呈对称分布，较大值出现在侧倾方向一侧胎肩处，且中心节点接地压力沿横向分布规律为先减小后保持不变，在靠近侧倾一侧时迅速增大;走行轮胎摩擦功分布不规律，较大值出现在侧倾方向一侧，且纵向节点摩擦功总和沿横向分布呈先减小然后缓慢增大的规律，在靠近侧倾一侧时基本呈指数增长；走行轮胎摩擦功总和及摩擦功偏度值都很大，侧倾是引起走行轮胎偏磨损的主要原因之一，走行轮胎在侧倾一侧的磨损较其他部位大，发生严重偏磨损。研究揭示了走行轮胎过弯时的偏磨损规律，对如何减轻走行轮胎的偏磨损，提高其使用寿命提供了理论依据。
Under curved complex condition, the uneven wear of straddle-type monorail vehicle running tire is serious. Uneven wear will not only increase operating costs, but also affect the safety of monorail vehicles. For this problem, a finite element model of tire and rail contact was established. Validity of the model was verified by comparing stiffness of experimental values with simulation values of running tire in three directions. Parameters of curved complex conditions were obtained from dynamic simulation model of monorail vehicle. By using numerical method, two ground states named relative slip and ground pressure of tire were analyzed under curved complex condition. Wear and uneven of running tire wear were evaluated by using total friction work and its skewness. Distribution rule of friction work, total friction work and friction work skewness were obtained. The results show that relative slip values of running tire is larger in the front left and right of tire shoulder, and average relative slip values of longitudinal nodes are larger in both ends and smaller in the middle along transverse direction. Ground pressure of running tire is symmetrically distributed in longitudinal direction. The larger values appear in tire shoulder of rolling side. Ground pressure of center nodes along transverse direction have a distribution rule of decreasing at first, then keeping constant, and increasing rapidly near rolling side. Friction work distribution of running tire is irregular, larger values appear in rolling side, and the total friction work of longitudinal nodes along transverse direction have a distribution rule of decreasing at first, then increasing slowly, and growing exponentially near the rolling side. Total value of friction work and skewness of friction work are very large. The rolling is one of the main reasons caused running tire uneven wear. Wear of running tire in rolling side is larger than that in other parts, and there is a serious uneven wear in rolling side. The uneven wear rule of running tire in a corner