- 期刊
不透水半圓形離岸堤對矩形港池水面波高分佈之研究
Diffraction of Water Waves by Impermeable Offshore semi-circle Breakwater
摘要
本文是利用複合邊界元素法(Composite BEM)在線性波浪理論下，探討等水深矩形港池配置不透水直線型或半圓形離岸堤後，其對港內水面波動之影響並作一比較。當離岸堤厚度相對於入射波浪波長之比很小時，離岸堤可以視為薄板結構物，因此可以採用本文數值模式加以計算，只須將通常邊界積分方程式(OBIE)與超奇異法線方向偏微分邊界積分方程式(HnDBIE)作線性組合，即可以解析海域中薄離岸堤問題。最後本文經由數個驗證例，並與過去學者比較均可以得到精度相當高的結果，說明了本研究數值解析法是一正確而且妥當可行的方法。由計算結果顯示，採用半圓形離堤凹口面向外海入射波浪方向，對於港池遮蔽效果相對於直線離岸堤更有功效。
並列摘要
The composite boundary element method (Composite BEM) has been proposed for solving the diffraction problems of water waves by a thin breakwater of arbitrary shape under the linear wave theorem. The Composite BEM is based on the composite boundary integral equation (Composite BIE), and the Composite BEM is the linear combination of the ordinary boundary integral equation (OBIE) and the normal derivative boundary integral equation with hypersingular kernels (HnDBIE).The method for solving the problem with degenerate boundary, such as the thin structure, is effective. Finally, the diffraction coefficients for different types of thin breakwaters are evaluated as illustration.