耦合颤振因素的叶片侧铣变形建模及实时抑制方法研究

Blade is the central structural unit in aero-engine and the other high-end equipment. But in milling process, coupling machining chatter and cutting deflection will lead to rapid decrease of surface finish and machining accuracy. To suppress the chatter and deflection in milling process, the method of chatter identification, deflection modelling and suppression coupling chatter will be studied in this research. The model of chatter identification based on pattern recognition will be established to recognize and forecast different types of chatter and unstable cutting process. Through analyzing production mechanism and interaction mechanism between chatter and deflection, analytical model of cutting deflection coupling chatter will be built to predict blade deflection in cutting region. Combined with analytical model and cutting process simulation, numerical model between cutting force, cutting parameters and cutting deflection will be established, and suppression algorithm of chatter and deflection based on real-time parameters adjustment will be presented. Integration method between above algorithm and real-time modular in open CNC system will be researched, then real-time suppression of blade deflection coupling chatter will be realized by scheduling new embedded thread of cutting parameters adjustment. This research will promote the development of high precision, high quality blade machining, and provide guidance for development of smart CNC system which could integrate the function of cutting process monitoring.

叶片是航空发动机等高端设备的核心结构单元。但在铣削过程中，切削颤振与受力变形的耦合作用导致其表面质量与加工精度急剧下降。为有效抑制叶片侧铣颤振与变形，本课题拟对颤振辨识、耦合颤振因素的切削变形建模及抑制方法进行研究。建立基于模式识别的颤振辨识模型，对不同类型颤振及不稳定切削过程进行识别与实时预报。通过分析颤振与变形的产生机理及相互作用机制，建立耦合颤振因素的切削变形解析模型，实现对叶片切削区域内变形量的准确预测。结合变形解析模型及切削过程仿真建立切削力、切削参数、切削变形间的数值模型，提出基于切削参数实时调整的颤振与变形抑制算法。研究颤振、变形抑制算法在开放式数控系统实时运行模块中的集成方法，通过合理调度系统模块内新嵌入的切削参数调整线程，实现耦合颤振的叶片侧铣变形实时抑制。项目的研究将推进叶片高精度、高质量加工的快速发展，为集成切削过程监控的智能数控系统研发提供理论指导。

叶轮叶片是航空发动机的核心零部件，本项目对切削过程中的颤振及变形因素进行控制，旨在提高叶片在加工过程中的精度和表面质量。首先对铣削颤振的机理进行研究，建立了叶片侧铣颤振的辨识模型，并对该模型进行系统集成与实验验证，结果表明，所建立模型可将叶片切削状态进行分类，有效识别出叶片在铣削过程中的不稳定状态；对耦合颤振的叶片切削变形进行建模与仿真，建立了基于动态切削厚度及动态切削力且包含弯曲与扭转的叶片侧铣变形模型，对叶片不同切削位置的切削深度与动态刚度进行提取拟合，利用有限元法获得了耦合颤振因素下的叶片侧铣变形；研究了叶片侧铣颤振与变形的抑制算法，基于耦合颤振的叶片侧铣变形模型、仿真结果与抑制算法制定了叶片切削过程实时控制策略，实现了在切削过程中叶片颤振与变形的实时控制。