近年來，海洋工程朝著深水區邁進，而海上浮式結構物亦日漸增加，隨之其錨碇系統成為重要議題。重力安裝錨(Gravity-installed anchor, GIA)為一種以錨體自重貫入底床進行安裝的錨碇基礎，其安裝效率高、成本低且不需借助額外安裝設施，而本文所使用形式為魚雷錨(Torpedo anchor)，在國際上已有實際運用案例。本研究運用計算流體力學 (Computational fluid dynamics, CFD)軟體FLOW-3D進行魚雷錨流固耦合作用之數值模擬，探討魚雷錨在擲錨(安裝)高度85公尺下，物體於水中自由落下的運動過程變化，觀察錨前端至底床瞬間之落下時間、衝擊速度、偏移角度、水平位移與觸地點位置。
本研究先探討改變錨的尾翼外觀之擲錨表現，而魚雷錨於擲錨過程中可能受水動力環境之影響，因此本文使用均勻流模擬不同海流流速及入射流向，對擲錨過程之物體運動進行分析。依據模擬結果，當錨的尾翼外觀不同時，主要影響擲錨過程之因素為尾翼的展弦比，尾翼數量則次之；而當海流流速愈大且作用於錨上之面積愈小時，對錨產生之影響愈大。
然而，為了改善受海流作用下錨於擲錨過程中的表現，本文進一步探討了兩種優化方法，分別為調整錨的初始傾斜角度(姿態)以及輔以衝擊機構並施予初始加速度，並且藉由適用度參數，得出適用擲錨過程之優化方法。其中，海流流速為1.0 m/s 時當錨在具有初始傾斜角度?＝5°的條件下時能達到較好之結果，施予初始加速度則在加速度為0.5g時有最佳之擲錨結果，不僅衝擊速度上升且偏移角度也下降，使錨較快速、筆直地貫入底床，得以有效提升擲錨的準確度。本研究之成果，能提供未來魚雷錨實際安裝之工程參考依據。

The purpose of this study is to simulate the free fall motion of a torpedo anchor in the water with installation height of 85 meters by using numerical software, FLOW-3D. In addition, the observation among falling time, impact velocity, displaced angle, horizontal displacement, and anchor location of the anchor's tip end to the seabed are discussed in this research.
To investigate the impact of changing the appearance of the anchor's fin and the potential influence of the hydrodynamic environment during installation, this study adopts uniform flow to simulate different current velocities and directions. The result shows that the larger current velocity and smaller loading area on the anchor leads to the greater impact on the anchor.
In order to enhance the precision of the anchor installation under current impacts, this study further discusses improvement methods, which are adjusting the initial angle and applying the initial acceleration of the anchor. Finally, using the fitness parameter to select the improvement method suitable for the installation. In this way, the results of this study could become an engineering reference for the practical installation of torpedo anchors in the future.

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