基于钢轨型面扩展法的车轮型面设计

Wheel Profile Design Based on Rail Profile Expansion Method

首先对欧洲国际铁路联盟(Union enternationale des chemins der fer,UIC)高速轮轨型面S1002/UIC60和我国准高速型面LMa/CHN60进行接触几何分析,认为LMa/CHN60型面共形度太低,对钢轨磨损以及滚动接触疲劳极为不利。以改善钢轨的受力状态为出发点,在对钢轨型面扩展法进行数值研究的基础上,采用钢轨局部型面扩展法,根据我国60kg/m钢轨设计出共形度较高的车轮型面。通过车辆轨道耦合动力学仿真确定车辆临界速度约为400 km/h,且具有较好的曲线通过性能。轮轨非赫兹滚动接触分析表明,在靠近钢轨一侧接触斑面积、应力等较LMa型面变化不大的情况下,离开钢轨一侧接触斑面积明显增大,接触应力降低约20%,钢轨与车轮的接触带变宽,钢轨接触频次得到改善。在车轮型面优化设计做了尝试性工作,以期为我国高速、重载以及城市轨道交通车辆车轮型面优化设计提供借鉴。

Firstly the contact geometry of UIC high-speed wheel/rail profile S1002/UIC60 and Chinese quasi-high-speed profile LMa/CHN60 is analyzed. The analysis result shows LMa/CHN60 profile has too low degree of conformity, which would have detrimental effects on wheel/rail wear and rolling contact fatigue. So, from the view point of altering the rail contact status, rail profile expansion method is researched numerically, and the partial rail profile expansion method is adopted to design wheel profile having higher degree of conformity with Chinese 60 kg/m rail. The vehicle ＆ track coupling dynamics simulation shows that the designed profile has critical speed about 400 km/h, and relatively better curving performance than LMa profile. Finally, the calculation of the wheel/rail elastic non-Herzian rolling contact shows that compared with the LMa profile the contact area, contact stress etc. of the approaching rail side contact have little changes, while the leaving rail side has obvious en-large in contact area and substantial decrease in contact stress, for approximately 20%. This design can enable a broader wheel/rail running band, alter the contact position and frequency, which will mitigate wheel/rail rolling contact fatigue.