Abstract
For the purpose of enhancing the control effect of a conventional Helmholtz resonator for absorbing incident sound in a wide frequency range, this paper presents a newly developed Helmholtz-based resonator. The principle of the resonator presented in the work is relied upon the frequency property of a flexible panel installed in a resonator cavity, thereby enabling to broaden the effective frequency range of the sound absorption. The resonance frequency of the panel is designed to tune to that of the resonator, so that the resonant peak is split into two. An absorption coefficient as well as acoustic impedance density of the resonator is derived analytically. Then, from a viewpoint of a numerical simulation, fundamental characteristics of the resonator system with those parameters are investigated. Finally, an experiment is conducted, demonstrating the validity of the proposed resonator.
