薄壳工件-电主轴系统热机一体化建模及其铣削稳定性研究

For the heat of the machine tool motorized spindle system under the working condition to affect milling stability of the thin shell workpiece, the study idea of this project is integrated modeling of thermodynamics and kinetics characteristics of thin shell workpiece - motorized spindle system. And then the evaluation criterion of milling stability of thin shell workpiece is studied to establish..The project will use W-M function to establish and solve the expression of the joint’s stiffness and micro contact critical contact area based on fractal contact theory. By solving the power spectrum function to identify the fractal parameters of the non perfect contact surface (the joint), the expression function of thermal contact resistance is gotten. According to kirchhoff's law, the heat balance equation set of the system's critical thermal nodes is established. Based on Floquet Nyquist Method, the universal milling force model of thin shell workpiece with periodic variation coefficient is gotten to establish thermal mechanical integration modeling of the thin shell workpiece - motorized spindle system. And then combined with the relevant experimental, the characteristic parameters of milling stability of thin shell workpiece in the critical stable state are identified..The project is expected to clarify the thermal-mechanical coupling mechanism of the workpiece - motorized spindle system, to establish the mapping relation between related parameters and the critical state. .The study results of the project will provide theoretical foundation for the running stability and milling stability of high-speed motorized spindle system of CNC machining center.

针对机床电主轴系统工作状态下形成生热源，从而影响薄壳工件铣削稳定性的问题，本项目提出将薄壳工件-电主轴系统热力学与动力学特性一体化建模的研究思路，进而研究建立薄壳工件铣削稳定性的评价准则。.项目将使用W-M函数研究建立并求解结合部刚度与微接触点临界接触面积的表达式；通过求解功率谱函数来识别非完美接触面（结合部）的分形参数，探求接触热阻的函数表达；依据基尔霍夫定律研究建立系统关键热节点热平衡方程组；基于Floquet Nyquist Method，研究建立具有周期变化系数的薄壳工件通用铣削力模型，从而进行薄壳工件-电主轴系统热机一体化建模；结合相关实验，研究辨识表征薄壳工件铣削加工中临界稳定状态的特征参数。.项目预期将阐明工件-电主轴系统热-机耦合机理；建立相关参数与系统临界稳定状态的映射关系。.项目研究结果将为提高数控加工中心电主轴系统的运行平稳性及薄壳工件铣削稳定性提供理论基础。

针对机床电主轴系统工作状态下形成生热源，从而影响薄壳工件铣削稳定性的问题，本项目提出将薄壳工件-电主轴系统热力学与动力学特性一体化建模的研究思路，以数控机床电主轴系统为研究对象，以转子动力学、传热学、分形理论等为基础，采用有限元方法、热阻网络法等建立了电主轴系统的热-力耦合模型，充分考虑了系统中动态特性与热态特性之间的互相影响，对电主轴系统不同工况下的动力学响应以及热力学特性进行了详细分析。进而，基于上述研究，建立了薄壳工件-电主轴系统热-力耦合模型，该模型能够有效预测系统在实际工况下的动力学与热力学特性、铣削稳定性区域等。并以此为基础，在铣削力系数辨识、机床主轴频响、工件动力学、稳定性预测以及铣削温度等方面进行了研究。本项目的研究能够为薄壁件的铣削稳定性分析提供理论依据，为数控机床电主轴系统的优化设计提供理论基础，具有一定的学术意义和经济价值。