正逆向重构技术在航空发动机机匣中的应用

The Application of Forward and Reverse Modeling Technology in Aviation Piston Engine Crankcase

为提高传统正、逆向工程设计中的模型重构效率与精度,解决航空发动机机匣因形状复杂导致实体造型困难的问题,研究逆向工程与正向建模相结合的模型重构方法及其特点。以某型航空活塞发动机机匣为研究对象,绘制机匣正逆向混合重建流程图,搭建测量扫描环境,利用三维扫描设备对机匣形面进行数据采集,并使用Geomagic Design X等软件进行数据处理与优化,最终得到机匣数字重构模型。通过偏差检测分析得出,模型平均重构精度误差小于0.5mm,重要配合端面平均误差小于0.1mm,与实际情况相吻合,验证了正逆向重构技术的正确性与便捷性,对航空发动机机匣性能预测、疲劳仿真及结构维修具有一定指导意义。

In order to improve the efficiency and accuracy of model reconstruction in traditional positive and reverse engineering design,and solve the problem of complicated shape and difficult physical modeling of aviation piston engine crankcase,the model reconstruction method combining reverse engineering and forward modeling and its characteristics are studied and introduced.Taking a certain type of aviation piston engine crankcase as the research object,we drew the flow chart of the positive reverse mixing reconstruction of the crankcase,set up the measurement and scanning environment by using the three-dimensional scanning equipment to collect the image of the crankcase surface.And Geomagic Design X and other software were used for data processing,optimization,and finally the crankcase digital reconstruction model was constructed.Through the deviation detection and analysis,it is concluded that the average reconstruction accuracy error of the model is less than 0.5mm,and the average error of the important matching end surface is less than 0.1mm,which is consistent with the actual situation and verifies the correctness and convenience of the forward and reverse modeling technology.It also has certain guiding significance to the performance prediction,fatigue simulation and structural maintenance of aviation piston engine crankcase.