Fatigue analysis of airfoil under different working conditions

Abstract

Within the flight mission envelope, the wing receives different aerodynamic loads in each mission stage, which results in bending and torsion alternating stress, which is prone to deformation or fatigue damage, threatening flight safety. Therefore, it is necessary to predict the fatigue life of the wing structure and maintain it in time to avoid accidents. Fluent software is used to analyze the aerodynamic load state of the wing when the lift-to-drag ratio is the largest under the three conditions of the climb, level flight, and landing, as the loading load of the wing, analyze the stress and strain of the dangerous points at each stage based on the finite element analysis platform, and determine Multiaxial fatigue state. The Brown-Miller multiaxial fatigue analysis method based on the critical surface was adopted, and the fatigue life analysis was carried out using the Fe-safe software and the Abaqus software. The results show that the minimum lifespan first appears at the root of the wing. In the Fe-safe analysis, the design life of the given wing structure is 40000 cycles, and the minimum life of the wing structure is calculated to be 58420 cycles, longer than the design life, and the life safety factor is 1.078, basically in line with the actual situation.