面向曲率约束的叶片自由曲面材料去除规律及打磨创成原理研究

叶片叶身曲面的加工质量直接关系到叶片的工作性能，对航空发动机、燃气轮机运行效率、使用寿命、安全性等具有重要影响。叶形曲率误差会严重影响叶片的气动及传热性能，但叶形曲率误差的形成及控制在加工中仍然没有得到很好的解决。为此，本项目将围绕面向曲率精度约束的航空叶片自由曲面打磨创成原理，从三个方面展开：首先，使用微分几何构造打磨工具局部近似诱导曲面，通过磨粒在柔性基体上变形作用的卷积叠加，实现柔性打磨工具叶身自由曲面去除函数的建模；其次，探讨以法截线局部几何特征为基础的流线曲率合成方法，建立最优化模型，实现面向叶身流线曲率约束的自适应打磨运动规划；最后，以诱导打磨工具曲面主曲率变化量为表征，基于叶片轮廓点云数据，分别建立面形误差、曲率误差模型，实现变曲率自适应打磨叶形精度分析与补偿。本研究可为曲率精度约束下的叶片自由曲面自适应打磨提供理论支撑，并为其在高精度叶片加工领域的应用奠定基础。

The machining quality of blade surface is directly related to the blade’s working performance, and has an important impact on the operating efficiency, service life and safety of the aeroengine and gas turbine. The blade curvature error will seriously affect the aerodynamic and heat transfer performance of the blade, but the formation and control of the blade curvature error have not been well solved. For this reason, this project will focus on the grinding and creating principle of aero-blade free-form surface facing curvature accuracy constraint, and start from three aspects. Firstly, use differential geometry to construct grinding tool local approximate induced surface and realize the modeling of free-form surface removal function of blade body for flexible grinding tool through convolution superposition of deformation effect of abrasive particles on flexible matrix. Secondly, this paper discusses the synthesis method of the curvature of the blade body in the streamline direction based on the local geometric characteristics of the section line, constructs the optimization model，and realizes adaptive grinding planning for the curvature constraint of the streamline. Finally, characterized by the change of the main curvature of the induced grinding tool’s surface, the form error and curvature error models are established based on point cloud data of blade contour, respectively. The accuracy analysis and compensation for adaptive blade grinding with variable curvature are also realized. This study can provide theoretical support for adaptive grinding of aero-blade free-form surface under curvature accuracy constraints, and lay a foundation for its application in the field of high-precision blade machining.