Underwater asymmetric acoustic transmission structure using the medium with gradient change of impedance  

作　　者：胡博 时洁 时胜国 孙玉 朱中锐 

机构地区：[1]College of Underwater Acoustic Engineering, Harbin Engineering University [2]Science and Technology on Underwater Acoustic Laboratory, Harbin Engineering University

出　　处：《Chinese Physics B》2016年第2期249-255,共7页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11204049 and 11204050);the Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China(Grant No.IRT1228);the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant Nos.20122304120023 and 20122304120011)

摘　　要：We propose an underwater asymmetric acoustic transmission structure comprised of two media each with a gradient change of acoustic impedance. By gradually increasing the acoustic impedances of the media, the propagating direction of the acoustic wave can be continuously bent, resulting in allowing the acoustic wave to pass through along the positive direction and blocking acoustic waves from the negative one. The main advantages of this structure are that the asymmetric transmission effect of this structure can be realized and enhanced more easily in water. We investigate both numerically and experimentally the asymmetric transmission effect. The experimental results show that a highly efficient asymmetric acoustic transmission can be yielded within a remarkable broadband frequency range, which agrees well with the numerical prediction. It is of potential practical significance for various underwater applications such as reducing vibration and noise.We propose an underwater asymmetric acoustic transmission structure comprised of two media each with a gradient change of acoustic impedance. By gradually increasing the acoustic impedances of the media, the propagating direction of the acoustic wave can be continuously bent, resulting in allowing the acoustic wave to pass through along the positive direction and blocking acoustic waves from the negative one. The main advantages of this structure are that the asymmetric transmission effect of this structure can be realized and enhanced more easily in water. We investigate both numerically and experimentally the asymmetric transmission effect. The experimental results show that a highly efficient asymmetric acoustic transmission can be yielded within a remarkable broadband frequency range, which agrees well with the numerical prediction. It is of potential practical significance for various underwater applications such as reducing vibration and noise.

关 键 词：asymmetric transmission IMPEDANCE GRADIENT 

分 类 号：O427[理学—声学]