Integrated design of porous materials and structures with scale-coupled effect

It is known that structural behaviors of cellular solids are dictated by the topology of the dense and porous regions, with a complex arrangement of microstructures of different sizes and topologies. An integrated design methodology using representative volume element (RVE) scale is proposed for the global stiffness maximization of the overall structure and the local design of RVE based on multi-scale computing. Influences of RVE aspect ratio, scale, and periodic arrangement style such as translation and symmetric pattern on the optimal design are investigated using the super-element method. By means of the dual optimization scheme and perimeter constraint, RVE is efficiently optimized with checkerboards being eliminated. Numerical results show that the proposed method can be used in the design of porous materials such as honeycomb panels and hierarchical cellular sandwich panels and the hierarchical cellular materials scale effects are well represented. This provides an innovative design concept for the lightweight structures.