Vibro-acoustic topology optimization for improving the acoustic insulation and mechanical stiffness performance of periodic sandwich structure.

The traditional parameter adjustment design makes it difficult to effectively regulate the acoustic insulation performance of periodic sandwich structures while meeting the lightweight and mechanical stiffness requirements. A dynamic three-field floating projection topology optimization (FPTO) method for periodic structures is proposed to meet the optimization requirements of low-noise and high-stiffness performance of lightweight periodic sandwich structures. The sound transmission loss is taken as the optimization objective, and the lightweight volume and mechanical stiffness performance are taken as the multiple constraints. The results show that a smooth topology configuration with superior sound insulation performance, high stiffness, and a freely customizable number of periodic cores can be obtained via the proposed method. The accuracy and effectiveness of the presented method are verified via 3D printing technology and impedance tube sound insulation experiments, providing an important reference for the optimal design of lightweight composite structures for vibration and noise reduction in transportation equipment.