Duct-Borne noise control using active adaptive Helmholtz resonators array

This article proposes a semi-active noise control method that involves the use of a periodic array of tunable Helmholtz resonators. This method is designed to be a more efficient, robust and broad-band adaptive attenuating effect than the traditional pass noise control methods used in duct-borne sound control. Based on the fundamental theory on sound waves propagating in a one-dimensional periodic duct system, the proposed control method combines band-gap attenuation using the side-branch resonators array with the autoadaptive system of noise control. The derived acoustic equations that take into account the plane sound wave propagation in viscous air within air duct walls are theoretically studied. Numerical computation is used to investigate the effectiveness of the proposed new semiadaptive noise control method for controlling transmission noise in a ventilation ductwork system.