Front and rear edge profile redesign method for adaptive processing

Abstract

The invention discloses a front and rear edge profile redesign method for adaptive processing. A blade-shaped crosshatch is divided into a front and rear edge near-end area, a transitional area and a blade body area, a tolerance area of the centroids of the front and rear edge near-end area is determined according to tolerance requirements for blade components, the tolerance area of the centroids is optimized to obtain a tolerance track which reflects the torsion deformation and position deformation, to satisfy the processing balance, coordinates of the centroids of the front and rear edge near-end area are transformed to obtain a redesign contour of the front and rear edge near-end area of the blade, a contour of the transitional area is fit under the constraint of smooth connection between the near-end area and the blade body, the front and rear edges are combined, the crosshatch is redesigned, and further the curved profile of the front and rear edges is obtained. The method has the advantages that the front and rear edges which are not arched can be processed, and the searching range is narrow during contour adjustment.

Description

technical field [0001] The invention relates to the field of profile design of the leading and trailing edges of blades, in particular to a method for redesigning the profile of leading and trailing edges of blade parts for adaptive processing. Background technique [0002] Blades are the key parts of aero-engines. In order to improve the performance of the engines, new blade structures have been continuously developed, which also put forward higher requirements for the manufacturing process. A new class of sandwich hollow wide-chord blades in aero-engines, the typical manufacturing process is: first use superplastic forming / diffusion connection to obtain a near-net-shaped blade blank that is very close to the size and shape of the blade, and then use adaptive CNC cutting to The front and rear edges are processed, and finally the surface including the blade profile is polished to obtain a blade that meets the design requirements. [0003] The middle part of the airfoil obta...

AI Technical Summary

Problems solved by technology

A small amount of literature has been published on the redesign of the leading and trailing edges of the blade. For example, the literature "Reconstruction of the model of the leading and trailing edges of precision forging blades for adaptive machining (Lin Xiaojun et al., Acta Aeronautica Sinica, 2015, 05: 1695-1703)" introduced a method based on cross-section. The method of reconstructing the leading and trailing edge models by measuring point fitting lines, theoretical section lines, and searched arc centers and radii. This method can effectively avoid the step difference between the blade body and the leading and trailing edges, and is suitable for circular arcs at the leading and trailing edges. However, it is not applicable to situations where the front and rear edges are hyperbolas, elliptical lines, free curves, etc.

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