斜浪中船船垂向加速度運動反應研究

On the Vertical Acceleraion Responses of a Ship in Oblique Seas

本研究以二維截片理論（USDDCMO）針對高速排水型單體船（RD-200）進行斜浪中之船艏垂向加速度運動反應分析，數值計算結果經瑞典SSPA水槽之船模試驗驗證，結果顯示USDDCMO計算能有效的預估單體船之船艏垂向加速度運動反應，規則波中，當航向角界於頂浪180度到橫浪90度時，實驗與理論計算結果相當吻合，但在艉斜浪航況，實驗與理論計算比較結果分散，其誤差原因可能在船模自推實驗中，必須保持船體航向之穩定，因而連續操舵造成額外的外力與運動偶合，其影響F.P.位置加速度運動反應；本船在非規則波中船艏垂向加速度運動反應驗證，包括海象五級、兩個前進速度、五個航向角，在F.P.位置之加速度運動反應之理論計算與實驗的比較，實驗與理論計算結果十分接近，確認數值模型之正確性。依據數值模型之驗證研究，本研究對高速排水型單體船在不同海況、不同船速、不同座位、不同航向之垂向加速度運動反應進行完整分析，並探討其在斜浪中之運動反應特性。 The study on the characteristics of vertical acceleration for a monohull vessel in oblique seas has been carried out. A two-dimensional strip theory (USDDCMO) has been used for predicting the vertical acceleration responses of the high speed displacement monohull (RD-200) in oblique regular and irregular waves. In order to verify the validity of the two-dimensional strip theory, the model test results of a free-running 1:25 scale hull model carried out in SSPA Maritime Dynamics Laboratory are used for comparison. The ship model is self-propelled, autopilot steered and frees to move in all six degrees of freedom. This project covered investigation of the F.P. vertical acceleration of RD-200 in both regular and irregular waves. The comparison between numerical predictions and experimental data shows a good agreement except that around the stem wave conditions. Furthermore, the characteristics of vertical acceleration for the RD-200 with different ship speed, seating location, wave heading and sea slate are discussed.