| Title |
A Study on the Absorption Performance of a Perforated Panel type of Resonator |
| Authors |
Hwayoung Song ; Yoonsang Yang ; Donghoon Lee |
| DOI |
http://dx.doi.org/10.6110/KJACR.2016.28.6.224 |
| Keywords |
공명기 ; 흡음계수 ; 다공 패널 ; 임피던스 Resonator ; Absorption coefficient ; Perforated panel ; Impedance |
| Abstract |
When aiming to reduce the low frequency noise of a subway guest room through sound absorbing treatment methods inside the wall of a tunnel the resonator is often more effective than a porous sound absorbing material. Therefore, the perforated panel type resonator embedded with a perforated panel is proposed. The perforated panel is installed in the neck, which is then extended into the resonator cavity so that it can ensure useful volume. The absorption performance of the perforated panel type of resonator is obtained by acoustic analysis and experiment. The analytical results are in good agreement with the experimental results. In the case of multiple perforated panel type resonators, as the number of perforated panels increase, the 1st resonance frequency is moved to a low frequency band and sound absorption bandwidth is extended on the whole. In order to obtain excellent absorption performance, the impedance matching between multi-panels should be considered. When the perforated panel in the resonator is combined with a porous material, the absorption performance is highly enhanced in the anti-resonance and high frequency range. In case of the resonator inserted with perforated panels of 2, the 2nd resonance frequency is shifted to a low frequency band in proportion to the distance between perforated panels. |