相位轉移法應用於雙體海洋結構物運動之三維分析

Three-Dimensionalanalysis on the Motions of Twin-Hull Ocean Structures by Phase Transfer Method

本文採用三維脈動型源點配合小板法作為基礎，解析單體結構物的入射、繞射及輻射問題，以求解在流場中所產生的壓力，並將得到的壓力利用座標轉換的方式，加入相位角的觀念，推導出雙體結構物約各項流體動力係數，求解結構物之六度運動量。由於本方法僅需計算單一結構體再加以轉換，即可得到雙體結構體間無交互作用情況下之流體動力係數，因此相對於有考慮兩結構體間交互作用影響的計算方式而言，本文所推導出的方法可節省計算時間及計算機資源。由本文計算實例可知對於交互影響小的海洋結構體的確可有效地使用相位角轉移法來求解。 The paper presents the source distribution method with the three dimensional pulsating source to analyze the corresponding hydrodynamic problems for the twin-hull body in waves. The phase transfer method is applied to simplify the six degrees of freedom motion prediction, which neglects the interactions between two hulls. In the present method, only the related hydrodynamic coefficients for the mono-hull are calculated and the phase transfer for each hull of the twin-hull body is then considered. Consequently the computation time can be saved because of neglecting the interaction effect between two-hulls. From the calculation results, we find that the present three dimensional phase transfer method indeed has its advantage in some respects and can be applied to some; hydrodynamic researches for twin-hull structures in waves. However some limitations for the speed and clearance between two hulls must be carefully concerned.