使用The DELTA方法(The Desingularized Eulerian-Lagrangian Time-domainApproach method)所發展之數值模型，被用來模擬船舶作航行運動時其產生之波浪，並計算其相對應之興波阻力。在本數值模型中，所謂「除奇點( Desingularization)」的技巧被應用。因此，在運算過程中，無須特殊處理面積分時存在奇點(Singularities)的問題，如此，程式的複雜度得以減低，過程中所需之運算時間均可被減少。本數值模型在時間域內採用全非線性(Fullynon-linearized)之合併自由液面邊界條件(Combined free surface boundaryconditions)及物體邊界條件(Body boundary condition)。文中亦使用造波器以產生所需的波浪，並引入計算區域中，以模擬有入射波情形之海面。文中以此模型，對Wigley及Series 60等船型在靜水平面及有入射波的情形下進行模擬計算。而因船體運動所產生之波浪形狀，被用來與實驗值作比較。 Fully nonlinear water wave problems are solved using TheDesingularized Eulerian-Lagrangian Time-domain Approach method (theDELTA method) in conjunction with a desingularized approach to solvethe mixed boundary value problem that arises at each time step. In thedesingularized approach, the singularities generating the flow fieldare outside the fluid domain. This allows the singularity distributionto be replaced by isolated Rankine sources with the correspondingreduction in computational complexity and computer time. Examples ofthe use of the method in three-dimensions are given for the excitingforces acting on a modified Wigley hull and Series 60 hull under theconditions of with/without incoming waves.
