Lightweight design of stiffening ribs layout of a bypass engine casing

This study focuses on the lightweight design of a specific bypass engine casing, considering the complex effects. A topology optimization approach is first employed to determine the optimal layout of stiffening ribs under various loading conditions. Additionally, taking into account the buckling stability requirements for the casing, the correlation between four common reinforcement configurations and structural buckling resistance is systematically studied. A hierarchical stiffening strategy on the basis of triangle and hexagonal patterns is proposed, and built a parametric model for the periodically stiffened casing. A comprehensive optimization design objective, based on stress levels of stiffening ribs and structural buckling resistance, is finally developed. The optimized reinforcement design for the bypass engine casing achieves a weight reduction of approximately 40% compared to the original design model. Moreover, it surpasses the structural stiffness and strength requirements and exhibits a significant enhancement of 212.9% in the critical buckling load when compared to a structure with a wall thickness of 1.3 mm. These advancements effectively ensure the operational stability of the bypass engine casing under severe load conditions.