Design optimization of a sandwich composite tube with auxetic core using multiobjective lichtenberg algorithm based on metamodelling

Abstract

In this paper, the multi-objective optimization of a sandwich composite tube with an auxetic reentrant core was done. Five different responses of the model were considered: mass; critical buckling load; natural frequency; Poisson’s ratio; and failure load under compression effort. The Response Surface Methodology was applied, and a new meta-heuristic of optimization called the Multi-objective Lichtenberg Algorithm was used to find the optimized configuration of the structure. In addition, a parametric analysis was performed to verify how each of the design factors influenced each of the responses. It was found that the unit cell height is the most significant factor for failure load, natural frequency, and mass. On the other hand, unit cell height has no significance for Poisson's ratio. Furthermore, it was also verified that the Poisson's ratio has no correlation with any of the other responses studied (failure load, critical buckling load, mass, and natural frequency). Finally, it was possible to improve (reduce) the Poisson’s ratio by more than 56% in the optimization of the modal performance and improve the mass, the Poisson’s ratio, the failure load, and the critical buckling load in the static performance. Thus, this paper shows something unprecedented in the literature to date when evaluating the multi-objective design optimization of a tubular sandwich structure with an auxetic core.