Transmission loss of a silencer using resonator arrays at high sound pressure level

Abstract

Helmholtz resonator is generally used to reduce the low frequency noise. However, it has only high transmission loss in a narrow band at the resonance frequency. In order to obtain broad band transmission loss, studies of a silencer using various resonator arrays have been carried out. These previous studies have been limited to low incident sound pressure level conditions with no change of impedance with respect to pressure. In the case of high sound pressure, the resistance increases due to nonlinear behavior at the neck of a resonator. As a result, the desired noise reduction performance cannot be achieved due to the transmission loss decrease. To predict the transmission loss of a silencer using resonator arrays at high sound pressure level, impedance variation depending on the incident sound pressure level should be considered. Furthermore, resonator’s numbers and order of arrangement are significant design parameters for design of transmission loss shape.