热-力耦合变截面涡旋盘高速精密铣削微观形貌与变形控制研究

The efficiency and reliability of scroll fluid machines are critically affected by significant acting forces, wrap deformation and inner leakage of uniform scrolls when applied to multi-wrap turn and large displacement conditions. However, the existing theory of non-uniform scroll machining could not reveal the mechanism of micro-topography formation and scroll wrap deformation. In addition, it is not capable of meeting the requirements of high precision and small deformation of the scrolls. From a standpoint of flexible profile design, the proposed project aims to improve surface quality and obtain even wrap deformation of scrolls in thermal-mechanical coupling based high-speed precision milling by comprehensively using of differential geometry, numerical simulation, optical microscopy measurement and analysis and high-speed milling experiments. Subsequently, micro-topography of wrap sidewall surface and its evolution law will be explored and the effects of process factors on micro-topography will be illuminated. Furthermore, the relationship between scroll wrap deformation and dynamic processing forces as well as wrap thickness will be explained based on mathematical model of dynamic and deformation of the scroll. Therefore, a novel “non-uniform scroll profile design and machining” theory integrated by control strategy of sidewall micro-topography and scroll wrap deformation will be founded. Meanwhile, a test bench for micro-topography and wrap deformation of non-uniform scroll based on high-speed precision milling will be created to verify the effectiveness of control strategy and theoretical models. The research results will provide fundamental and technical supports for effective design and application of scroll machinery.

等截面型线涡旋盘在多圈数、大排量应用中较大的受力和变形导致泄漏损失严重，影响涡旋机械的效率和可靠性。现有变截面涡旋盘加工理论不能揭示涡旋盘微观形貌形成和涡旋齿变形机理，无法满足高表面质量和小变形的涡旋盘加工要求。本项目以热-力耦合变截面涡旋盘高速精密铣削为研究对象，以提高侧壁面加工质量、实现涡旋齿均匀变形为宗旨，从变截面型线柔性化设计角度切入，拟综合运用微分几何、数值模拟、光学显微测量与分析、高速铣削实验等手段，探索涡旋盘侧壁面形貌特征和演化规律，阐明高速精密铣削工艺参数对侧壁面形貌的影响机理；研究涡旋盘动力学响应行为，阐明涡旋齿变形与动态载荷及壁厚变化的关联规律；创新侧壁面形貌和涡旋齿变形控制策略，形成“变截面涡旋型线设计与加工”理论。搭建热-力耦合变截面涡旋盘微观形貌和变形测试系统实验台架，验证理论模型与控制策略的有效性。为高效变截面涡旋机械的设计和应用提供理论依据和实证支持。

复杂型面涡旋盘是涡旋机械的关键零部件，对涡旋机械性能有至关重要的影响。项目以动态温度场和应力场耦合变截面涡旋盘高速精密铣削加工为研究对象，以实现涡旋齿的均匀变形、提高侧壁面加工质量为宗旨，基于Frenet标架建立了等壁厚、渐变壁厚和变壁厚涡旋齿数学模型，分析了各类型线几何特性，制定了变截面涡旋盘型线优选策略；进行热-力耦合高速铣削涡旋盘系统动力学理论与实验研究，建立变截面涡旋齿的动态切削力模型、温度场模型和切削仿真模型，研究高速铣削变截面涡旋盘颤振现象，揭示涡旋齿变形机理和变形规律，得到了最佳的铣削工艺参数组合；完成变截面涡旋齿三维形貌测量与表征，测量45#钢及硬铝7075材料三段基圆渐开线变截面涡旋齿侧壁面形貌，运用一维和二维功率谱密度方法量化表征涡旋齿形貌的频率-空间分布信息，定量研究高速铣削过程工艺参数、材料参数对侧壁面形貌和表面形貌的影响规律及其作用机理。在上述研究基础上，形成完整的“变截面涡旋型线高速精密铣削加工”理论。研究结果为变截面涡旋齿高速精密铣削加工和变形控制提供了基础数据和参考依据，为复杂型面关键零部件的精密制造提供理论基础与技术支撑。共发表学术期刊论文38篇；获得甘肃省机械工程学会科学技术一等奖等科研奖励4项；培养研究生19人，其中博士生3人，外国留学硕士生1人；获得兰州理工大学优秀博士学位论文1人，获得甘肃省青年教师成才奖1人。