Deformation and fatigue life analysis of axial flow compressor blade based on fluid-structure interaction

Abstract This study employs the fluid-structure interaction (FSI) method to quantitatively evaluate the impact of different tip clearances on compressor blade performance, focusing on the influence of flow fields on structural behavior. The computational fluid dynamics (CFD) models utilized herein have been corroborated with experimental data. The vibration characteristics of blades were obtained based on the Campbell diagram, and fatigue life prediction was finally carried out. The results indicate that as the blade tip clearance increases from 0 times the design clearance to 2 times the design clearance, the tip vortex in blade tip flow field gradually strengthens, leading to a decrease in pressure ratio and efficiency, while the stable operating range of blade is shortened. Blade vibration modes are predominantly influenced by centrifugal loads, with tip clearance exerting a minor effect on these characteristics. The Campbell diagram indicates that the blade has low resonance margins at the design speed ranges of 54–59 % and 78–83 %, which are prone to resonance. After FSI calculations, it was found that the increase in blade tip clearance enhances the wing tip leakage vortex, reduces the aerodynamic load on blade, gradually reduces the maximum deformation of blade, and increases the fatigue life of blade.