深海超低频WKB反转简正波模型  

Very-low-frequency WKB turning mode model in deep ocean

作　　者：朴胜春 詹建康[1,2,3] PIAO Shengchun;ZHAN Jiankang(National Key Laboratory of Underwater Acoustic Technology,Harbin Engineering University,Harbin,150001;Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University),Ministry of Industry and Information Technology,Harbin,150001;College of Underwater Acoustic Engineering,Harbin Engineering University,Harbin,150001)

机构地区：[1]哈尔滨工程大学水声技术全国重点实验室,哈尔滨150001 [2]工业和信息化部海洋信息获取与安全工信部重点实验室(哈尔滨工程大学),哈尔滨150001 [3]哈尔滨工程大学水声工程学院,哈尔滨150001

出　　处：《声学学报》2024年第4期784-802,共19页Acta Acustica

基　　金：国家自然科学基金项目(12174048)资助。

摘　　要：提出了一种基于抛物柱函数的深海超低频WKB反转简正波模型。采用比较方程法,选择形式解为抛物柱函数的映射方程,给出了典型深海声速剖面情况下简正波方程的抛物柱函数WKB近似解和近似条件。数值分析了Epstein声速剖面环境下简正波本征函数的全局近似误差,求解了Munk声速剖面环境下的简正波声场。结果表明,所提方法与经典WKB近似方法和Langer变换方法相比全局近似误差更小,并且可将海水层看成一个整体,适用于求解深海超低频声传播问题。A WKB method is presented to compute very-low-frequency turning modes in the deep ocean.Utilizing the comparison equation method,the WKB approximate solution based on the parabolic cylinder function for the depth-separated wave equation is obtained by comparing with the exact solution for mapping equation.The approximate conditions are further discussed.The global approximate error of the mode function is numerically analyzed for an Epstein layer,while the normal mode sound field is assessed for a Munk environment.The proposed method demonstrates a smaller global approximation error compared to the classical WKB approximation method and the Langer transform method.The results indicate that the seawater layer can be regarded as a whole,making it suitable for investigating very-low-frequency sound propagation in the deep ocean.

关 键 词：简正波模型 WKB近似 抛物柱函数 全局近似误差 

分 类 号：P733.2[天文地球—物理海洋学]