【作者】 崔大宾；

【导师】 李立； 金学松；

【作者基本信息】 西南交通大学 ， 机械设计及理论， 2013， 博士

【摘要】 轮轨型面优化一直是铁路技术研究的主要内容。匹配关系较好的轮轨型面可以提高列车的运行质量,降低铁路及列车维修成本。轮轨几何形状不匹配,或磨耗后匹配性能恶化的轮轨型面将增加轮轨的磨耗与伤损,甚至影响车辆的动力学性能。针对列车运营中存在的具体问题合理设计车轮踏面,可以起到延长车轮踏面镟修周期,降低铁路运营成本的目的。本文第1章对轮轨关系的研究历史和现状进行了详细论述,对目前的车轮型面优化设计方法进行了分析,明确了车轮型面优化的意义与研究方向。第2章介绍了轮轨匹配性能参数、轮轨相互作用力及车辆系统动力学性能求解方法,用以分析踏面各项性能指标。对我国现有高速踏面性能进行了比较分析,指出了各踏面的优缺点,为踏面设计提供参考。高的轮轨接触应力是导致轮轨磨耗与伤损的主要原因之一,减小轮轨接触应力以减小轮轨伤损一直是车轮踏面设计的一项主要任务。第3章以减小轮轨接触应力为目的,以动态轮轨法向间隙最小为目标开发了车轮型面的正解方法。该方法充分考虑了车轮型面不同位置的重要性。利用改进的SQP方法对车轮踏面进行了优化设计,数值分析表明,设计踏面可以在不降低其它性能的情况下,有效降低轮轨接触应力。目前高速列车均采用轻量化设计,与轮轨接触应力相比,车轮型面应首先满足列车高速运行时的稳定性及平稳性要求。由于各国铁路运营条件存在差异,无法直接采用国外高速车轮踏面外形,需根据线路运营条件对车轮踏面重新设计。传统经验设计法可以充分考虑目前踏面存在的优缺点,设计结果通常具有较好的推广性。第4章采用经验法对某型车车轮踏面进行了设计,给出了两种减小轮轨游隙的踏面设计方案,以满足列车350km/h～380km/h高速运行需求。与经验设计法相比,反求设计法具有较高的踏面设计效率及较低的成本。第5章通过对轮轨接触几何关系的详细推导,获得了根据轮径差反推踏面外形的踏面设计方法,并开发了收敛性较好的高速并行优化算法。根据实测踏面磨耗特性对踏面轮径差进行了调整,反求设计了车轮踏面外形。目前绝大多数车轮踏面优化方法只追求踏面运营初期较好的轮轨匹配性能及车辆动力学性能,对踏面磨耗之后的性能考虑较少,且通常将踏面设计与车辆参数的研究相分离。而较好的踏面设计应保证车轮一个镟修周期内具有较好的动力学特性,这就要求车轮踏面设计需适当考虑车辆系统的动态性能。第6章综合利用了前几章介绍的车轮踏面设计方法,提出了车轮踏面“均良设计”方法。此方法可以综合考虑车轮的磨耗状态、车辆的悬挂参数、轨道不平顺以及速度等级等。结合线路列车实测踏面磨耗外形,对车轮踏面进行了优化,取得较好的效果。第7章介绍了各高铁线路不同型号列车车轮磨耗状态,详细分析了列车横向失稳与车轮凹形磨耗的关系。以CRH3型车为例,基于车轮踏面均良设计理念设计了新的踏面外形,并对设计前后踏面性能进行了详细分析,结果表明新设计踏面具有较好的轮轨匹配特性及抗凹形磨耗性能,可以有效延长踏面镟修周期。最后给出了车轮踏面设计的相关结论与展望。更多还原

【Abstract】 The wheel/rail profile optimization has always been a focus of railway research. Optimized profiles can increase the quality of the running trains and reduce the related maintenance costs. Deteriorated or mismatched profiles greatly influence the wear and other damages of both wheels and rails, and even drop the vehicle behavior.. Obviously, a wheel-rail profile design, developed on the basis of observations of wheel tread problems, can reduce the frequency of wheel re-profiling, and further the operational cost of the railway.Chapter1of this thesis reviews the history and the present situation of the research into wheel profile optimization. Chapter2introduces the methods employed in this thesis to solve the wheel/rail matching performance parameters, the wheel/rail interaction and vehicle system dynamics. In order to create a reference for wheel profile design, the advantages and disadvantages of the wheel profiles of Chinese high-speed trains are also explained.Excessive wheel/rail contact stress is the root cause of wheel damages. Therefore, to reduce wheel/rail contact stress is one of the main objectives of the profile optimization. Chapter3develops a forward solution method for designing wheel profile based on the wheel/rail normal gap, the main objective of which is to reduce the wheel/rail contact stress. The improved sequential quadratic programming method is used to solve the optimization model. The results of the numerical analysis show that wheel/rail force stress of the new profile is largely reduced without sacrificing the dynamic performance of the wheelset.For the high-speed vehicles with low axle load, however, the riding quality and running stability of the vehicle is more important objective than the wheel/rail contact stress. Because of the differences between the Chinese high-speed railway system and those in other countries, the wheel profiles behaved well at abroad may not be used directly in China, and modifications or further improvements are normally necessary. The traditional method can fully consider the advantages and disadvantages of the old profiles, so that the obtained results can easily be extended. In chapter4, the wheel profile of vehicle is designed by the traditional method. Two design proposals with small wheel/rail clearance are achieved to meet vehicle running requirement at the speed of350km/h～380km/h.In comparison with the traditional method, the inverse method has some features such as high production efficiency and low design cost. In chapter5, the wheel/rail contact geometry relationship was derived in detail, the wheel profile inverse design method is developed based on the RRD function, and the parallel algorithm which has high efficiency and good convergence is developed. The RRD function is adjusted based on the measured wheel profile and the new wheel profile is obtained using this method.Currently, the vast majority of wheel profile design methods only focuse on the matching performance and dynamic behavior in the beginning stage, and are usually separated from the vehicle dynamics. However, a successful wheel profile should ensure the high dynamic performance of the vehicle, ideally in the whole re-profiling period. Chapter6developed a new wheel profile design method on the basis of the methods introduced in the previous chapters, which is named as "average-fine design method".With this method the wheel profile is optimized with the consideration of contact stress, dynamic performance of the vehicle, wear of wheel tread and so on. For validation, a new profile was designed using this method based on the measured wheel profiles and its sound effects were proved in vehicle operation.Chapter7introduces the wear state of wheels in different lines and analyzes the effect of hollow-worn wheel on vehicle stability in detail. Take CRH3as an example, a wheel profile was designed using the average-fine design method and the performances of the new profile are investigated in detail and compared with the original wheel. The results show that the new profile has the better performances and can alleviate the hollow wear on the wheel, thus, the period of re-profiling can effectively be extended.Finally, the conclusions and prospect of the wheel profile design method are given.更多还原