An anisotropic filter-based adaptive hierarchical stiffener topology optimization method

The new generation of aerospace equipment necessitates advanced design for complex load-bearing environments, which is challenging for traditional structural forms. Consequently, this paper introduces a hierarchical topology optimization method for stiffened shells. This method utilizes the proposed hierarchical model and a filtering-based reinforcement description method to facilitate adaptive reinforcement configurations, such as variable shell thickness, lattices, and stiffeners of varying spacings and sizes. Two examples are presented: for a plate scenario, under identical constraints, the proposed method can obtain a hierarchical stiffener layout and achieve a 16.8% increase in stiffness compared to the traditional optimized single-level stiffener layout. For a complex engineering curved shell, the proposed method achieves hierarchical designs that meet service conditions, which traditional single-level stiffening approaches struggle to accomplish. Additionally, several discussions illustrate the robustness of the method across various service conditions. The proposed method can provide improved performance compared to traditional methods and can adaptively optimize to obtain a single-level stiffener layout when it is more reasonable in terms of design requirements.