含早期故障的高速机车齿轮传动系统非线性动力学行为研究

Gear transmission system is one of the key components in high-speed locomotive bogies. Traction efficiency and safety of locomotives are affected by the performance of the gear transmission system. The gear transmission system in high-speed locomotives is a kind of strong nonlinear system which features high speed, heavy load, complex construction. Considering the effect of complex meshing and rail excitation, the gear transmission system with incipient faults will lead to complex dynamic behaviors, which might deactivate the traction function, or even weaken the safety of the train. By adopting the theory and method of gear dynamics, nonlinear dynamics and vehicle dynamics, a gear transmission model for high-speed locomotives is proposed in this project, while time-varying meshing stiffness, backlash in circular tooth and bearing clearance etc., are considered. The nonlinear dynamic behavior of gear transmission system with incipient typical faults and influence on the dynamic performance of locomotives will be researched by adopting the technology of theoretical analysis and numerical simulation. The experiment of gear transmission system with incipient typical faults will be carried out on a rolling test rig, where the theoretical analysis results will be validated and corrected by the experiment data. The damage formation mechanism and evolution law of the gear transmission system will be researched in the project with the help of the explicit finite element method. The research findings of this project have very important theoretical significance and use value in deepening the fault diagnosis technology and guiding the design, manufacture and maintenance of the gear transmission system.

齿轮传动系统是高速机车走行部的关键部件之一，其工作状态直接影响着列车的牵引效果和运行安全。高速机车齿轮传动系统的主要特点是速度高、负载大、结构复杂，是一类典型的强非线性系统。在复杂啮合关系和轨道激扰等因素的作用下，齿轮传动系统极易产生损伤而表现出复杂的动力学行为，轻则导致牵引失效，重则威胁列车的运行安全。本项目拟采用齿轮动力学、非线性动力学和车辆动力学的理论和方法，建立考虑时变啮合刚度、齿侧间隙和轴承间隙等非线性因素的高速机车齿轮传动系统动力学模型，采用理论分析和数值仿真的方法，对含早期故障的高速机车齿轮传动系统的非线性动力学行为及其对机车动力学性能的影响情况进行研究。通过滚动实验台的典型齿轮故障实验，检验并修正理论计算结果，结合显式有限元求解算法探索系统的损伤机理和演化规律。本项目的研究成果对深化齿轮传动系统的故障诊断技术、指导系统的设计、制造和维护等均具有十分重要的理论意义和实用价值。

齿轮传动系统是高速机车走行部中的关键子系统，主要由齿轮、箱体、支撑滚动轴承等构成，具有结构复杂、高维强非线性、服役工况多变、服役环境恶劣等特点，其运行状态和服役性能直接影响着高速列车的行车安全。本项目主要采用了齿轮动力学、非线性动力学和车辆动力学的理论和方法，建立了考虑时变啮合刚度、齿侧间隙和轴承间隙等非线性因素的高速机车齿轮传动系统动力学模型，采用理论分析和数值仿真的方法，对含早期故障的高速机车齿轮传动系统的非线性动力学行为及其对机车动力学性能的影响情况进行了研究。通过模拟实验台、故障实验台和实车线路试验等，检验并修正了理论计算结果。研究结果表明：带裂纹故障轮齿在其参与啮合时会降低齿轮的总体刚度，随着故障轮齿的啮合点从齿根逐渐移动到齿顶，其对总体刚度的影响会逐步增大。裂纹深度越长，会使总体刚度降低越明显。随着裂纹的加深，时域图上的冲击性波动会更加明显，频谱图上的边频带也会增大。带偏心故障齿轮在一个旋转周期的啮合过程中，会使齿轮中心距随转角周期性变化，导致时变刚度的幅值和重合度均呈现周期性变化。偏心故障会使齿轮系统的动力学响应在时域图上出现以故障齿轮旋转周期为周期的周期性波动，随着偏心程度的增大，这种波动的幅度呈增大趋势；在频谱图上开始出现轴频，且在高次谐波周围出现以轴频为基频的不对称边频，随着偏心程度的加深，其幅值会响应增大。本项目的研究结果一方面可以为我国高速列车技术得以持续发展并保持领先地位奠定坚实的理论基础；另一方面可以有助于解决复杂激励和动态载荷作用下齿轮传动系统失效机理及服役性能演化等科学问题，推动我国动力学与控制、车辆动力学等学科的发展。