title: Acoustic attenuation performance through a constricted duct improved by an annular resonator.
abstract: Acoustic attenuation performance through a constricted duct is greatly improved by an annular resonator. A method based on the Green's function for a semi-infinite circular duct is proposed to calculate the transmission loss, where the velocity distributions are assumed to be uniform at the constriction inlet/outlets and at the inlet to the annular resonator. From an analogous acoustical circuit, the effect of higher order evanescent modes on the quarter-wave resonance is described by an extra length. The improved acoustic attenuation performance is also confirmed by an experiment.
authors.affiliation: Department of Marine Technology, Ocean University of China, Qingdao 266100, China fengqipeng@163.com, yellowshower@163.com, gkyu@ouc.edu.cn.
authors.forename: Qipeng
authors.initials: Q
authors.lastname: Feng
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Huang
authors.forename: Gaokun
authors.initials: G
authors.lastname: Yu
authors.forename: Xiangbin
authors.initials: X
authors.lastname: Meng
mesh_terms: D000162:Acoustics / Q000295:instrumentation*; D004867:Equipment Design; D008962:Models, Theoretical; D009038:Motion; D009622:Noise / Q000517:prevention & control*; D013997:Time Factors; D014732:Vibration