Wave mode computing method using the step-split Padé parabolic equation  

作　　者：Chuan-Xiu Xu Guang-Ying Zheng 徐传秀;郑广赢(Hangzhou Applied Acoustics Research Institute,Hangzhou 310023,China;Science and Technology on Sonar Laboratory,Hangzhou 310023,China)

机构地区：[1]Hangzhou Applied Acoustics Research Institute,Hangzhou 310023,China [2]Science and Technology on Sonar Laboratory,Hangzhou 310023,China

出　　处：《Chinese Physics B》2022年第9期354-361,共8页中国物理B（英文版）

基　　金：Project supported by Young Elite Scientist Sponsorship Program by CAST(Grant No.YESS20200330).

摘　　要：Models based on a parabolic equation(PE)can accurately predict sound propagation problems in range-dependent ocean waveguides.Consequently,this method has developed rapidly in recent years.Compared with normal mode theory,PE focuses on numerical calculation,which is difficult to use in the mode domain analysis of sound propagation,such as the calculation of mode phase velocity and group velocity.To broaden the capability of PE models in analyzing the underwater sound field,a wave mode calculation method based on PE is proposed in this study.Step-split Pade PE recursive matrix equations are combined to obtain a propagation matrix.Then,the eigenvalue decomposition technique is applied to the matrix to extract sound mode eigenvalues and eigenfunctions.Numerical experiments on some typical waveguides are performed to test the accuracy and flexibility of the new method.Discussions on different orders of Padéapproximant demonstrate angle limitations in PE and the missing root problem is also discussed to prove the advantage of the new method.The PE mode method can be expanded in the future to solve smooth wave modes in ocean waveguides,including fluctuating boundaries and sound speed profiles.

关 键 词：parabolic equation propagation matrix eigenvalue decomposition 

分 类 号：O175.26[理学—数学]