Theoretical and experimental study of a two-dimensional circular stealth acoustic lens

The detection of underwater acoustic signals is a key focus in ocean development, and acoustic metamaterials play a crucial role in achieving this goal. Pentamode metamaterials exhibit fluid-like properties, allowing for the propagation of compressional waves without shear waves. In this study, a two-dimensional circular stealth acoustic lens based on pentamode metamaterials was proposed. By applying the transformation acoustics theory, the theoretical properties of circular stealth acoustic lenses were calculated, and they were verified with Finite Element Method (FEM). A practical model was designed with pentamode metamaterials and silicone oil, and its performance was verified with FEM software. A half-model was fabricated, and underwater experiments demonstrate that it does not effectively affect the propagation state of acoustic waves. The consistency between theoretical results and experimental findings highlights practical significance and broad application prospects for the circular stealth acoustic lens in the field of acoustic detection.