由於油輪大型化，港口無法容納大型油輪，故須透過海外卸油浮筒進行卸油，單點繫泊系統常作為海外卸油設施，提供油輪繫泊及進行卸油作業，海外卸油亦伴隨風險，若有漏油事件發生，將對生態及漁業造成衝擊。故本研究以高雄港外海卸油浮筒掛載柔性立管作為研究標的，運用ANSYS AQWA以及OrcaFlex等軟體進行模擬，在油輪單點繫泊卸油作業條件下，探討單點繫泊系統以及柔性立管之安全性，以及當繫纜故障導致斷裂失效後，對單點繫泊系統及柔性立管引致之影響。
首先，建立緩波型(lazy wave)立管及陡波型(steep wave)立管，分別討論在風波流耦合作用下，對柔性立管曲率及張力之影響，評估其是否適用於高雄港外海海域。研究結果顯示，兩種配置之柔性立管在卸油作業條件下，張力與曲率皆在安全範圍內，雖然兩種配置之立管皆能在高雄港外海作業環境條件下生存，但在動力放大因子結果中，惟陡波型立管可有更好的適應能力，故在進一步繫纜失效分析中使用陡波型立管作為研究標的。
在繫纜失效分析中，考量油輪不同裝卸情況下，探討不同風向及不同流向時，單點繫泊系統之影響及柔性立管之安全性，本研究規劃四種不同繫纜失效情境進行分析，搭配美國石油學會(API RP 2SK)錨鏈張力規範及中國港口技術規範之泊位水域範圍進行探討。研究結果顯示，當迎波方向一條錨鏈失效時，其餘錨鏈張力、油輪漂移範圍及立管張力曲率都在安全範圍之內，尚能繼續進行卸油作業；當迎波方向兩條錨鏈連續失效時，油輪漂移範圍超出泊位水域，與周圍船隻有碰撞危險，此時立管張力曲率也超出材料本身允許範圍，亦有漏油之風險；另外當一條大纜失效時，由於油輪漂移範圍變化大，雖未超出泊位水域，但須注意剩餘迎波方向之錨鏈張力上升狀況；當迎波方向一條錨鏈且一條大纜失效時，部分試次中迎波方向錨鏈張力超越80% MBS，不滿足規範之安全要求，可能有連續斷纜之虞。本文之研究成果將可作為外海油輪單點繫泊作業風險管控之參考依據。

The purpose of this study is to examine the safety of the flexible riser attached to the single point mooring system in the Kaohsiung harbor offshore area. The study uses ANSYS AQWA and OrcaFlex to conduct numerical simulations, considering the effects of wind, wave, and current in different directions. The study analyzes the impact of tension and curvature of the flexible risers in various configurations, namely lazy wave and steep wave. Additionally, the study examines the safety of the mooring system under the wave, wind, and current forces in the event of mooring failure of the single point mooring system. It also discusses whether the allowable curvature and tension of the riser are exceeded, leading to oil spill pollution.
The results show that both configurations of the risers can withstand the operating environment of the Kaohsiung harbor offshore area. However, the dynamic amplification factor shows that the steep wave riser is better suited for application in Kaohsiung harbor. Furthermore, in the event of anchor chain M1 and M2 failure, the berthing area of the tanker will be exceeded, and the flexible riser will also be damaged. To prevent the risk of oil spills, it is necessary to evacuate nearby ships promptly and suspend oil discharge.

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