Control switch layout-design for active structural acoustic control of piezoelectric curved shell structures in shallow sea

Existing acoustic topology optimization methods integrate the traditional finite element methodboundary element method (FEM-BEM) to optimize the layout of piezoelectric structure in free space, thereby improving the performance of active structural acoustic control (ASAC). Unfortunately, the inability of the traditional finite element method-boundary element method to deal with the reflected sound from waveguide boundaries limits their application in the optimization design of piezoelectric structures submerged in shallow seas. In addition, previous piezoelectric structure layouts designed for specific working conditions cannot realize online control of acoustic radiation for diverse working conditions in engineering practice. Therefore, a novel topological layout-design scheme for control switches of piezoelectric curved shell structures to bring down acoustic radiation in a shallow sea is proposed based on the velocity feedback control scheme and the combined method of the FEM, the added mass method (AM) and the image method-based boundary element method (I-BEM), which can handle the fluid-structure interaction and boundary sound reflection problems. A finite element formulation for the piezoelectric curved shell element is presented. In this context, the sensitivity analysis equation for sound pressure level is derived. The optimization problem is formulated in the framework of an artificial active damping model with penalization. The volumetric densities describing the control switch distribution are assigned as the design variables. Numerical examples demonstrate the validity of the proposed optimization approach and its potential applications in practical designs.