Three-dimensional coupled-mode model and characteristics of low-frequency sound propagation in ocean waveguide with seamount topography  

作　　者：Ya-Xiao Mo Chao-Jin Zhang Li-Cheng Lu Sheng-Ming Guo 莫亚枭;张朝金;鹿力成;郭圣明(Key Laboratory of Underwater Acoustic Environment,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China;China State Shipbuilding Corporation Systems Engineering Research Institute,Beijing 100094,China)

机构地区：[1]Key Laboratory of Underwater Acoustic Environment,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China [2]China State Shipbuilding Corporation Systems Engineering Research Institute,Beijing 100094,China

出　　处：《Chinese Physics B》2022年第8期453-462,共10页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.11804360);the IACAS Frontier Exploration Project(Grant No.QYTS202103);the Key Laboratory Foundation of Acoustic Science and Technology(Grant No.2021-JCJQ-LB-066-08)。

摘　　要：Large-scale topography, such as a seamount, substantially impacts low-frequency sound propagation in an ocean waveguide, limiting the application of low-frequency acoustic detecting techniques. A three-dimensional(3D) coupledmode model is developed to calculate the acoustic field in an ocean waveguide with seamount topography and analyze the3D effect. In this model, a correction is introduced in the bottom boundary, theoretically making the acoustic field satisfy the energy conservation. Furthermore, a large azimuth angle calculation range is obtained by using the operator theory and higher-order Pade approximation. Additionally, the model has advantages related to the coupling mode and parabolic equation theory. The couplings corresponding to the effects of range-dependent environment are fully considered, and the numerical implementation is kept feasible. After verifying the accuracy and reliability of the model, low-frequency sound propagation characteristics in the seamount environment are analyzed. The results indicate lateral variability in bathymetry can lead to out-of-plane effects such as the horizontal refraction phenomenon, while the coupling effect tends to restore the abnormal sound field and produces acoustic field diffraction behind the seamount. This model effectively considers the effects of the horizontal refraction and coupling, which are proportional to the scale of the seamount.

关 键 词：coupled-mode model three-dimensional sound propagation seamount topography horizontal interference structure 

分 类 号：O422[理学—声学]