非線性內波對水下音傳的三維擾動效應

Three Dimensional Variation of Underwater Acoustic Propagation due to Nonlinear Internal Wave

張志瑋(Zh-Wei Zhang)

指導教授 ： 陳琪芳

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.02461

摘要

南海存在世界上振幅最大的海洋內波，其內波擾動振幅可達到百公尺，垂直海洋流速可達每秒2.5公尺，對海洋環境會產生劇烈的擾動現象，導致在此區域的水下音傳作業必須考慮海洋內波對音傳訊號產生擾動效應。本研究透過NLIWI(Non-Linear Internal Waves Initiatives)實驗的海洋環境與聲訊資料，分析海洋內波對於水下聲音傳遞所造成的三維擾動。利用KdV (Korteweg-de Vries)方程式建立上升型與下沉型內波的環境，及FOR3D三維數值模式，分析海洋內波通過時對於水下音傳所造成的三維擾動效應。

關鍵字

水下音傳 ； NLIWI ； 內波 ； 三維擾動效應 ； FOR3DFOR3D

並列摘要

There is a biggest internal wave in the South China Sea. The amplitude can more than one hundred meter and the vertical current velocity can large then 2.5 meters per second. The internal wave perturbs the water column dramatically which affect sound propagation greatly. This thesis is about the sound propagation’s variation in three dimensions due to internal waves. The acoustic and environment data are from the 2007 NLIWI experiment. We study both depression and elevation internal waves simulates KdV formula analysis the 3D effect on acoustic propagation using FOR3D model.

並列關鍵字

underwater acoustic propagation ； NLIWI ； nternal wave ； three-dimensional vibration ； FOR3D

參考文獻

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