Enhancing metamaterial performance for acoustic sensing in flow

Turbulent pressure fluctuations can compromise the accuracy of far-field acoustic measurements when microphone arrays are flush-mounted on surfaces exposed to fluid flow. To address this, recent advances in acoustic metamaterials have introduced novel approaches to enhance the signal-to-noise ratio of these measurements. In this paper, new techniques for coupling the sound and flow field to a meander metasurface are discovered through computational acoustics modeling and examined through wind tunnel testing in Virginia Tech’s Subsonic Modular Anechoic Research Tunnel (SMART). The results provide insight into the optimal shape for allowing sound waves into a metamaterial while attenuating turbulent boundary layer noise.