重燃组合转子系统的接触界面损伤特性及动力学研究

The disk-rod-fastening combined rotor system in heavy-duty gas turbine depends on the series of contact interfaces to transmit forces and torques. The fretting damage of contact interfaces is one of key problems which may influence the structural integrity, structural strength and dynamic stability of combined rotor system. Recently, the study of interface fretting damage mainly concentrates on the simple linkage structure. The literature reports about the fretting damage characteristics of contact interfaces for combined rotor and their effects on the system dynamics are hardly seen. For the typical annular plane/plane and terminal face tooth contact interfaces of combined rotor, the fretting damage characteristics of contact interfaces and their effects on the structural strength and dynamic characteristics of combined rotor system are studied by theoretical analysis, numerical simulation and experiments in this project. Firstly, the influence rules of complex loading circumstances such as centrifugal force, torque, high temperature and so on, structural parameters of interfaces and rotor vibration on the fretting damage and fatigue of interfaces are investigated. So the time-dependent fretting damage characteristics of annular plane/plane and terminal face tooth contact interfaces are revealed. The internal relationship between fretting damage and structural parameters of contact interfaces are found out. Secondly, the quantized representation methods of contact stiffness and damping of interfaces are established. And the computational method of bending stiffness of combined rotor with the consideration of interface damage is presented. Then the influence mechanisms of interface damage on the structural strength and dynamic characteristics of combined rotor system are explained. Finally, based on the above research results, the universal dynamic analytical theory and method could be perfected. At the aim of reducing interface damage, the structural design criterion of contact interfaces of combined rotor system is proposed. These findings may provide the theoretical and technical supports for the independent research and development and stable operation of combined rotor system in heavy-duty gas turbines of our country.

重型燃机盘式拉杆组合转子依靠众多的接触界面传递力和扭矩，接触界面的微动损伤是影响组合转子系统的结构完整性、结构强度和动力稳定性的关键因素。目前界面损伤研究多集中于简单连接结构，针对组合转子的界面损伤特性及其对系统动力学的影响研究鲜见文献报道。本项目针对周向拉杆组合转子中的典型环形平面/平面、端面齿接触界面，通过理论分析、数值模拟和实验研究，查明离心力和高温等复杂载荷、界面结构参数、转子振动等因素对界面微动损伤和疲劳的影响规律，揭示界面的时变性损伤特性；提出考虑界面损伤的界面接触刚度和阻尼的量化表征方法及组合转子弯曲刚度计算方法，揭示界面损伤对组合转子系统结构强度和动力学行为的影响机制，完善组合转子系统的动力学分析理论与方法。本项目从减小界面损伤的角度出发，提出接触界面设计准则，为我国燃机组合转子系统的自主研发及稳定运行提供理论和技术支持。

重型燃机盘式拉杆组合转子依靠众多的接触界面传递力和扭矩，接触界面的微动损伤是影响组合转子系统的结构完整性、结构强度和动力稳定性的关键因素之一。本项目通过对组合转子的接触效应和动力学行为研究，揭示了接触界面的微动损伤特性及影响参数，阐明界面损伤对盘式拉杆组合转子结构强度和动力学特性的影响规律。.本项目研究工作进展顺利，按计划完成了研究任务。主要研究成果有：.1、建立了环形平面接触界面的轮盘装配有限元模型，研究其在不同载荷工况（拉杆预紧力、转速、扭矩、温度）、不同拉杆参数（拉杆失谐、拉杆数目、拉杆位置）、不同轮盘特性（弹性模量、泊松比、摩擦系数）下接触应力、剪切应力、相对滑移距离、磨损深度等微动参量的分布规律。.2、通过扭矩-角位移曲线、界面接触状态等研究，分析了动态载荷作用下不同因素（角位移幅值、拉杆预紧力、摩擦系数）对微动磨损运行行为的影响。.3、基于有限元分析软件并结合Fortran语言编译，建立了接触界面磨损的累积分析模型，研究了不同扭矩、预紧力、转速条件下接触界面微动参数随循环次数变化的时变性分布规律。.4、建立了端面齿结构有限元模型，分别研究了预紧力、扭矩、离心力、温度、材料参数和拉杆参数等条件下齿面接触压力、滑移距离和磨损的分布规律及各类载荷对端面齿接触特性和磨损的影响规律。.5、基于GW经典统计学接触模型，提出了含接触界面的轴段抗弯刚度计算方法；应用集总参数法，建立了一种初始弯曲转子的动力学分析方法—间接等效弯矩法，并通过与已有分析方法的对比，验证了所提出分析方法的正确性。同时基于初始弯曲转子的动力学方程，分析了整体燃机初始弯曲转子的动力学特性。.6、设计并搭建了环形平面接触界面以及端面齿接触界面的微动磨损试验台。在不同微动循环次数下，测试并分析了环形界面以及端面齿齿面三维表面形貌、表面轮廓随时间的变化情况，给出了磨损深度随时间的变化规律，并测试了端面齿磨损对组合转子动力学特性的影响。