Method for attaching strain gauge to engine blade

Abstract

The invention provides a method for attaching a strain gauge to an engine blade, which comprises the steps of calculating and determining the attaching position, the attaching direction, the attaching side, a central point A and a direction reference point B of the strain gauge on the engine blade through CAE software; selecting datum reference points M, N, and measuring the straight line distance from the datum reference points M, N to the central point A and the direction reference point B; determining actual positions of the central point A and the direction reference point B on the engine blade according to a method of arc intersection by taking the datum reference points M, N as circle centers; and attaching the strain gauge to the engine blade according to the actual positions. The strain gauge attaching method is simple to operate, has low requirements for equipment, can be applicable to positioning for strain gauge attaching of blades with a non-disk structure and a large torsion angle, avoids selection for a local coordinate system and positioning for a coordinate origin, also avoids influences imposed on positioning by torsion of the blade and is high in precision.

Description

technical field [0001] The invention relates to the field of detection of engine blades, in particular to a method for pasting strain gauges on engine blades. Background technique [0002] Measuring stress levels with strain gauges is a common means of stress measurement for aeroengine blades. The patch position and direction of the strain gauge have a great influence on the accuracy of the test. Usually, the patch position and direction need to be calculated and determined by CAE software such as finite element analysis software. How to keep the position and direction of the strain gauge consistent with the position and direction determined by the CAE software calculation is a key factor to ensure the accuracy of stress measurement. [0003] One method usually used to determine the position of the patch on the real blade is the three-coordinate positioning method. This method needs to establish a local coordinate system in the CAE software, give the local coordinates of th...

AI Technical Summary

Problems solved by technology

[0005] In the above two mounting methods, when determining the mounting direction of the strain gauge, the current engineering mainly relies on visual inspection, and the accuracy of determining the mounting direction is low, and there may be large errors

[0006] In addition, the existing technology has many restrictions on the direction of the strain gauge patch, and it is difficult to determine the patch in any direction by visual inspection

When the patching direction is parallel or perpendicular to the leaf edge or tip of the blade, the error of visual inspection is small, but when the patching position is in the middle of the blade or the patching direction is irregular, visual inspection is prone to large errors

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