本研究求解波浪通過繫纜浮式結構物之問題，探討波浪與繫纜浮式結構物互相作用下之動力特性。考慮波浪、浮式結構物與受波浪作用力之繫纜，於頻率領域之互相作用問題，其中浮式結構物的運動包含水平(sway)、垂直(heave)以及轉動(roll)等三個運動自由度。波浪場的求解為使用邊界元素法，纜繩動力分析則利用Leonard(1988)運動方程式，由有限元素法數值積分，建立纜繩運動方程式有限元素法模式，考慮纜繩受波浪作用力，使用Morison公式作計算，利用繫留點的邊界條件與結構物運動方程式合併，最後整個問題再聯立波浪場和繫纜浮式結構物運動方程式求解，一併求解波浪場。
模式建立過程中有波浪與自由浮式結構物作用之計算，確認波浪場之正確性，以及所造成的浮式結構物運動特性，接著單獨測試纜繩有限元素法運動方程式之合理性，確認計算正確之後再把兩者合併求解。與Sannasiraj et al.(1998)試驗和數值結果比較，說明模式的正確性，利用所建立之模式也對Morison作用力效應，以及纜繩鬆緊情形進行討論。結構物於纜繩拉緊狀態時，還可有運動造波情形，與固定浮式結構物結果有差異，而纜繩較鬆弛時結果接近自由浮式結構物情形。

In this study, the problem of waves incident on cable moored floating structures is studied. Fully coupled motion among waves, floating structure and cables are included, which are steady and periodic problems. The motion of floating structure includes sway, heave and roll three degrees of freedom. A boundary element method is used to solve the wave field. The dynamic analysis of cable motion equation is used by Leonard(1988), and a finite element method is used to solve. By the numerical integral, it can establish the FEM model of cable motion equation. Morison equation is used in calculating cable forces induced by waves. Cable equation is combined with the structure equation using matching conditions at attaching points. Finally wave field and structure-cable motion equation are solved simultaneously.
The model development includes the interaction of wave and freely floating structure, and tests the Finite Element Model of cable motion, and the combination of wave and moored floating structure. The present solution is compared with experiment results and numerical results presented by Sannasiraj, et al. (1998). It shows correctness of the model. Using the present model, the effects of Morison forces and the case of taut or slack cable are discussed. In the case of taut cable, the results are different from that of the fixed floating structure due to radiation of the structure motion. But in the case of slack cable, the results are closed to that of the free floating structure.

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