本研究擬利用計算流體動力學方法模擬斜坡引發之碎波事件，並進一步分析了波浪對離岸風力發電機基樁的衝擊過程中的交互作用。經由Reynolds Averaged Navier-Stokes (RANS) equation並結合有限體積法在二相流之耦合，可利用Boussinesq方法得到雷諾應力，進一步在自由液面的數值設定上採用RNG k-ε紊流模型。基樁幾何外型及計算流域皆透過六面體網格生成。藉由Irschik在德國漢諾威的大型造波水槽所進行的實驗結果驗證，並且提供了準確的波浪波高、波浪荷載及基樁結構上的壓力數據。本文將探討離岸風力發電機基樁在波浪作用過程中受碎波相似參數ξ_0、波高和波浪載荷等條件的影響，並通過EMD和HHT方法將波浪載荷的總力分解為準靜態力和砰擊力。此外，本研究將砰擊係數、上升時間、持續時間及砰擊力分析的結果進行總結。同時，本研究也將討論離岸風力發電機基樁周圍正規化溯升高度的分佈情形。

This study used computational fluid dynamics (CFD) to simulate breaking waves induced by sloping beds and to analyzes the impact of these waves on an offshore wind turbine (OWT) foundation. A Reynolds-Averaged Navier-Stokes (RANS) equation was established to numerically analyze the water surface of two-phase fluids by using a volume of fluid method. The Boussinesq approach was used to determine the Reynolds stresses for developing a Re-Normalisation Group (RNG) k-ε turbulence model. The cut-cell method was used to generate grids for the monopile geometry and the computational domain. The results of the numerical model for the wave elevation, wave load, and pressure on the foundation structure were validated by comparing them with the experimental results obtained by Irschik (2002) at the Large Wave Channel, Hannover, Germany. Next, the wave elevation and wave load subject to the surf similarity parameter ξ0 on the OWT foundation were examined. By using empirical mode decomposition (EMD) and the Hilbert–Huang transform (HHT), the total wave load forces were decomposed into the quasi-static force and slamming force. Furthermore, the wave load analysis would be summarized by considering the slamming force coefficient, rising time, duration time, and impulse. The normalized run-up height of the wave around the OWT foundation was also examined.

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