Structural-acoustic coupled modeling of a tunable membrane-type acoustic metamaterial with experimental validation

The finite element method is widely employed to analyze the noise reduction properties of membrane-type acoustic metamaterials (MAMs). However, it is typically suitable for scenarios where membrane deformations are minimal and subjected to uniformly distributed prestress, thereby limiting the design space of MAMs and hindering their application in more complex noise environments. In this paper, we propose a tunable MAM along with a tailored finite element modeling strategy. The tunable sound absorption characteristic is enabled by applying out-of-plane deformations to a silicone membrane. Additionally, the acoustic-structural coupling evaluation framework can account for the contributions of non-uniform prestress distribution and geometric nonlinearity induced by out-of-plane deformations. The reliability of this modeling method is subsequently validated through impedance tube experiments. The results demonstrate that this high-fidelity modeling framework aligns well with experimental outcomes, and the proposed MAM can achieve tunable sound absorption in the low-frequency range.