全非線性時間域數值分析模型之建立已成為研究浮體運動領域之必然發展趨勢。本文所述之次奇點數值模型，即The DELTA方法（The desingularizedeulerian-lagrangian time-domain approach method）。其中次奇點（Desingularization）之作法即將傳統方法中分布於計算區域面上之各奇點移至計算區域之外。本數值模型在時間域內採用全非線性之合併自由液面邊界條件及完全物體邊界條件。本文對直壁及非直壁形浮體作振盪時，其運動過程中，因為速度之變化而產生相對應之明顯非線性效應進行數值模擬；並以此模型進行計算、對計算結果作討論。 The numerical model stated in this work takes the DELTA method (Thedesingularized eulerian-lagrangian time-domain approach method) as itstheoretical basis. Desingualrization means to move the singularitiesthat traditionally located right on the boundaries of thecomputational domain out of the domain, hence, the special treatmentfor the singularities is avoided. In addition, a mixedEulerian -Lagrangian description technique is adopted to solve theproblem of wave overturn. The boundary conditions applied in the timedomain numerical model built in this thesis are fully nonlinearcombined free surface boundary condition and exact body boundarycondition. The variations of free surface are simulated when differenttypes of non-wall-sided floating bodies are moving with forcedoscillating motions. The numerical results for the motions of a 2-Dwall-sided/non-wall-sided floating body agree well with experimentaldata. A series of a floating body under different modes of motions andwater depths are conducted, and then the application range of theDELTA method in handling arbitrary shapes of floating bodies istested. The numerical results obtained using the DELTA method arepresented and discussed in this paper.
關聯:
八十九年度中華民國力學學會年會暨第二十四屆全國力學會議論文集=24th National Conference on Applied and Theoretical Mechanics, 頁N.A.(CD)
