近岸水域波浪變形數值模擬模式之研究

Numerical Modeling of Wave Deformations in the Nearshore Zone

陳美蓮(mei-lien Chen)

指導教授 ： 蔡丁貴

國立臺灣大學/工學院/土木工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.01909

摘要

本研究選擇以緩坡方程式為基礎，利用緩變因子建立數學控制方程式(任文華,1993；吳明全,1995)，再以Galerkin有限元素法建立數值模式用以模擬近岸波浪變形。新控制方程式並納入碎波能量消散項，用來解析近岸波場的折射、反射、繞射及碎波現象。本研究係於緩坡方程式中直接加入能量消散係數模擬，以疊代方式計算碎波帶內波高之變化。和前人之試驗值比較後可發現相關數值計算之結果不僅能合理的解析波場，且在碎波之模擬方面，理論與試驗數據亦呈現合理的一致性。

關鍵字

緩坡方程式 ； 緩變因子 ； 有限元素法

並列摘要

Based on the mild-slope equation, a slowly-varying factor has been introduced to derive a new governing equation (Jen,1993 ; Wu,1995) by Galerkin method of the finite element approach. An item is added to include breaking wave energy dissipation in the governing equation. It is intended to simulate the nearshore wave field with combined refraction, the reflection, the diffraction and the breaking wave phenomenon. Wave transformations with wave-breaking energy dissipation across the surf zone are solved through iterative method. Present numerical result are then compared with experimented measurement (Maruyama, 1984) in a case of offshore beakwater. Reasonable agreement is observed.

並列關鍵字

the mild-slope equation ； slowly-varying factor ； the finite element approach

參考文獻

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