Full-Scale Isogeometric Topology Optimization of Porous Thin-Shell Structures

Thin-shell structures are widely applied in aerospace, automotive and other engineering fields. In order to realize ultra-lightweight design, porous thin-shell structures have gained much attention. This paper proposes a full-scale isogeometric topology optimization method based on Kirchhoff–Love shell model to design porous thin-shell structures. In this method, high-order continuous non-uniform rational B-splines (NURBS) are used to describe the geometry of thin shells and construct C1-continuous Kirchhoff–Love shell elements. The effective density field is established on the control mesh to describe the topological configuration of a thin-shell structure. Isogeometric analysis (IGA) is used to unify geometric and analysis models, which effectively eliminates geometric approximation error and improves analysis accuracy. The proposed method generates bone-like porous structures by imposing local volume constraints in the proximity of each control point. The size of holes in the porous thin-shell structures can be adjusted by changing the local volume constraints and their influence radii. Numerical examples are given to verify the effectiveness of the proposed method, which can design porous thin-shell structures with high damage robustness.