Structural Acoustic Reduction via Piezoelectric Actuation and Adaptive Eigenvector Optimization Algorithm

Abstract

The purpose of this research is to investigate the feasibility of utilizing the adaptive eigenvector optimization algorithm to find the optimal combination of left and right eigenvectors for active structural acoustic reduction. As depicted in the previous studies, the structural acoustic radiation depends on the structural vibration behavior, which is strongly related to the mode shape distributions (represented by the right eigenvectors of system) as well as the ability of disturbance rejection (represented by the left eigenvectors of system). In this research, a novel adaptive optimization algorithm is developed to determine the optimal combination of left and right eigenvectors of the structural system for active structural acoustic control. The sound suppression performance index (SSPI) is defined by combining the orthogonality index of left eigenvectors and the modal radiation index of right eigenvectors. Through the proposed adaptive eigenvector optimization algorithm, both the left and right eigenvectors of the structural system are adjusted such that the SSPI quantity decreases, hence the optimal combination of the corresponding left and right eigenvectors of the closed-loop system can be found for reducing the structural acoustic radiation. The optimal combination of left-right eigenvectors is then synthesized to determine the feedback gain matrix of the closed-loop system. The result of the active acoustic control shows that the proposed method can significantly suppress the sound pressure radiated from the vibrating structure.