Acoustic liners for modern aero-engine noise reduction
Last updated on April 7, 2022
Attenuating the low-frequency component of aero-engine noise is challenging due to the mass and volume constraints when applying conventional noise mitigation techniques using liners and foams. To address it, acoustic liners constructed by Helmholtz resonators with extended necks (HRENs) are developed. An analytical noise reduction model of this kind of liners are established through combining the equivalent medium model and the transfer matrix method, based on which inhomogeneous liners design methodology for maximizing the attenuation capability was developed. To investigate the aero-dynamic and aero-acoustic performance of the liners subjected to high-intensity incidence, an advanced grazing flow tube was built up with the incident SPL
