Acoustic metamaterial design for noise reduction in vacuum cleaner

In this study, we investigate the acoustic metamaterial (AMM) design for flow noise reduction when using a vacuum cleaner. The AMM was based on the principle of Helmholtz resonators, and metamaterial design variables were defined to reduce noise to approximately 1.5 and 2.5 kHz bands. An acoustic simulation was performed considering the thermoviscous effect using the designed AMM, and a transmission loss in the simulation results was calculated using the four-microphone method. Finally, noise experiments were performed on a vacuum cleaner equipped with metamaterial. Through this, the noise reduction performance of metamaterial predicted through simulations was verified, thereby showing the selective implementation of noise reduction in the desired frequency band.