內重力波與透水牆之互制研究

The study of interaction between the internal wave and a permeable wall

林志祥(Chih-Hsiang Lin)

指導教授 ： 孔慶華

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.00695

摘要

摘要
多孔介質透水牆常被應用於海岸工程中，此結構物可減少波浪的反射，能夠降低波浪對於結構物本身的力量，以期能增加結構物（如防波堤、護岸）之使用年限。波浪經一多孔介質透水牆，會產生穿透及反射等現象，其和多孔結構物之孔隙率和幾何形狀皆有密切的關係。
本文前半部分探討一均質( homogeneous )、等向( isotropic )之多孔透水牆立於兩層不互溶，不可壓縮，無黏滯性之流體中，兩端為無限長之流域，上下邊界皆為固定、不可穿透之表面，並引用多孔雷諾數(porous Reynolds number)為微擾法中之微小參數，利用其求解邊界值問題。
本文後半部分是以 梯形多孔介質透水牆為討論重點，欲觀察透水牆之表面重力波通過斜向透水牆後之壓力及波高變化，由於台灣四面環海，陸地資源有限，故朝海洋發展乃勢之所趨，而梯形多孔透水牆可用來模擬岸邊之防波堤，用以討論海浪通過後之波高變化及能量衰減之情形。

關鍵字

內重力波

並列摘要

Abstract

Porous medium permeable wall is often used for coast construction work. This structure can reduce the reflection of wave and decrease the force acting on the structure itself, so as to increase the life of structure (such as breakwater, coast protector). When the wave is passing through porous medium permeable wall, the penetration and reflection phenomena will be occurred, which have close relationship with the porosity ratio and geometric shape of porous structure.

The first half of this study discusses the homogeneous and isotropic porous wall. It is put within two layers of immiscible, incompressible, and non-viscous fluid. Both ends are infinite blow region. Top and bottom boundaries are fixed and impermeable surface. The porous Reynolds number of micro-disturbance method is used to solve boundary problem.

The last half of this study discusses trapezoidal porous medium permeable wall. The pressure and wave height change of surface gravitational wave passing through declined permeable wall is observed. Due to Taiwan is surrounded by sea with limited land resources, it is the trend to expand the development to the ocean. The trapezoidal porous permeable wall can be used to simulate the breakwater at the coast which is able to be used to discuss the wave height change and energy dissipation of wave passing through this structure.

並列關鍵字

internal wave

參考文獻

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