EXPERIMENTAL STUDY AND FINITE ELEMENT ANALYSIS OF DOVETAIL ATTACHMENTS

2017-11-09
In this study, the contact stresses in the dovetail-rim region of an aero-engine compressor disc under the action of the centrifugal forces of the blades are investigated. Dovetail-rim consists of two parts: the blade and the disc. Highly stressed areas occur at the edges of the interface of the disc and the blade during the operation. Fretting fatigue is commonly seen in dovetails, which is caused by high stress gradients. An experimental setup which is capable of performing tension test on a dovetail rim attachment is designed. Strain gauges and a 2D digital image correlation system (DIC) are used to measure the strains. Finite element (FE) models are created for comparisons. Two sets of experiments are conducted. In the first experiment, it is seen that the misalignment of the specimens causes asymmetric contact condition in the contact pairs of dovetail. Therefore, inconsistencies between the results are observed. In the second experiment, changes are made to prevent the asymmetry giving results more consistent to the finite elements analysis (FEA). However, in the first two experiments, it is seen that the system is extremely stiff, the displacements and the strains measured are small. Therefore, these measurements are highly sensitive on tolerances and imperfections.

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Citation Formats
A. A. Akay, D. Çöker, A. Kayran, and E. Gürses, “EXPERIMENTAL STUDY AND FINITE ELEMENT ANALYSIS OF DOVETAIL ATTACHMENTS,” 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/54517.