Tunable noise and vibration reduction on a piezoelectric metamaterial panel: modelling and validation

Locally resonant metamaterials (LRMs) exhibit remarkable noise and vibration reduction by suppressing elastic wave propagation within specific frequency ranges. This effect, known as a stop band, is achieved by adding resonant elements onto a flexible host structure at sub-wavelength scales. However, conventional LRMs have fixed stop bands, limiting their applicability to non-stationary noise and vibration problems. This work presents a piezoelectric LRM panel, where piezoelectric elements are attached to a lightweight A3-sized panel and shunted with synthetic inductance circuits to enable tunable stop bands. A coupled electromechanical finite element (FE) model is developed in COMSOL, with FE matrices exported to MATLAB for dispersion diagram analysis using a Wave FE approach. Computational efficiency is enhanced via Bloch Mode Synthesis for model order reduction. The panel and shunt circuits are realized and tested on the KU Leuven Soundbox, a cavity exhibiting low-frequency acoustic modal behavior. Vibration and sound intensity measurements validate the numerical predictions, demonstrating the effectiveness of the modeling strategy and confirming the strong noise and vibration attenuation achieved by medium-sized piezoelectric LRM panels.