Research On Model Reconstruction Of Aero-Engine Damaged Blades And Laser Cladding

Aero-engine blades are long-term operated in harsh environment. Because of high temperature and pressure, as well as foreign object impacts, blades may have various defects. In terms of prolonging the service lives of blades, repair is an inevitable choice since replacement is far more expensive. 3D model reconstruction of damaged blades is one of the key technologies of blade repairing.A method is put forward to reconstruct the 3D digital model of blade, which does not need original design model of the blade. Firstly, the point cloud of broken blade is denoised. Aimed at the issue of mistaken and missed judgments of the point cloud denoising algorithms with different curvatures, a kind of adaptive denoising algorithm based on angle thresholds is proposed. Secondly, the digital models of blades which are damaged in different parts are respectively reconstructed. For tip damaged blade, based on GM(1,1) cross section curve(CSC) reconstruction algorithm, the 3D digital model is reconstructed. The precision of model is improved by reconstructing the CSC of blade tip. For middle part damaged blade, it only needs to construct the CSCs in undamaged part, and then loft the CSCs to reconstruct the 3D digital model. In this way, the calculation amount is reduced and the modeling efficiency is improved with a satisfactory precision accuracy. The applicable field of this remodel method is extended effectively because the original design model of the blade is not needed to be used. Finally, the error analysis and the flow field analysis of the 3D digital model are presented. The results turn out that the proposed 3D digital model can meet the technical requirements prescribed in the aircraft engine maintenance manual. The digital model is used to generate the 3D print and the applicability of the model is verified. Laser cladding repair experiment of damaged blade is completed and well effect is obtained.