Assessing Acoustic Black Hole performance via wavenumber transforms

This work investigates the application of embedded grids of Acoustic Black Holes to the noise and vibration reduction of plate structures. Lighter high loss damping treatment solutions are sought by designers for efficient vehicle noise and vibration control applications. In this work measured velocity responses of plates were analyzed using wave number transform methods to evaluate the vibration performance of periodic grids of embedded Acoustic Black Holes. The results showed that wavenumber spectra offer useful physical insights for analyzing ABH behavior that are not available through other kinds of analysis. The wavenumber spectra were also used to investigate the structural acoustic coupling via radiation efficiency estimates. The results showed that ABHs convert acoustically fast waves into acoustically slow waves, resulting in reduced radiated sound in addition to reducing the mechanical vibration levels. The results give designers critical insight for designing and implementing treatments using Acoustic Black Holes for efficient, high performance, noise and vibration reduction of critical structures.