Simulation Analysis and Experimental Study of Underwater Composite Sound-Absorbing Structures Under High Hydrostatic Pressure

Underwater sound-absorbing materials serve as crucial components for acoustic stealth in submersible equipment such as submarines. With advancements in sonar technology and the increasing diving depths of underwater vehicles, there are growing demands for enhanced pressure resistance and low-frequency sound absorption performance under high hydrostatic pressure. To address these challenges, researchers have made significant progress in matrix material development and acoustic structure design to improve compressive sound absorption capabilities. Some scholars have investigated the effects of geometric deformation and mechanical parameter variations in hydroacoustic materials under hydrostatic pressure on their sound-absorbing properties, while others have introduced acoustic metamaterials into underwater applications, offering novel design approaches for sound-absorbing materials. This study proposes a composite underwater sound-absorbing structure by integrating cavity-backed absorbers with membrane-type metamaterials. Through finite element simulations, we examine the structural deformation and acoustic performance variations under hydrostatic pressure, along with an analysis of its sound absorption mechanisms. Simulation results predict that this composite structure maintains excellent low-frequency broadband absorption characteristics even under high hydrostatic pressure, a conclusion further validated by experimental measurements.