Vibration Suppression and Flutter Control in Sandwich Plates Using Strut-Augmented Cores

Abstract The auxetic sandwich plates have a better solution to the vibration and noise control of aerospace and mechanical structures. Within the scope of this article, the dynamic and aeroelastic behavior of four re-entrant auxetic core topologies, cell 0, cell B, square, and star, as sandwich composite laminates, is investigated systematically with the inclusion of additional strut elements to increase the stiffness and tailored vibration. We obtain accurate architectural-specific equivalent material properties by adapting an existing hybrid method that uses voxel-based 3D numerical homogenization as well as first-order shear deformation plate theory (FSDT). For the first time, how those topology-specific effective properties influence plate-level modal localization and flutter are investigated in this study. Modal analysis shows that adding a central star strut increases frequency separation and mode localization and substantially improves vibration attenuation compared with conventional re-entrant or honeycomb cores. The star and cell B structures exhibit delayed flutter onset and limit vibration amplification under high-speed aerodynamic loading. The outcomes are compared with the high-fidelity finite element simulations, according to which the proposed model is robust to a variety of boundary conditions.