本研究是針對公開油輪船型KVLCC2使用OpenFOAM軟體進行計算流體力學分析。本研究分別採用靜態網格與動態網格達成船舶阻力試驗的模擬，並觀察艉跡流與船體造波之波浪的分布情形。其中靜態網格僅對阻力值進行預估；動態網格則是對阻力值、俯仰量 (Trim)、下沉量 (Sinkage) 進行預估。其中俯仰量與下沉量為微小數值，在單純使用實驗船模參數 (如質量和重心位置) 進行模擬時，容易因為船模圖檔在離散化或是網格建立後和真實幾何間產生微小的誤差，進而改變船模的移動和旋轉中心，最終造成過大的模擬誤差。本研究提供改善此現象的方法: XCG (Center of gravity in x direction) 修正流程，並且證實有效修正俯仰量與下沉量過大誤差的問題。

The study is to use OpenFOAM for computational fluid dynamics (CFD) analysis. Static and dynamic grid were used. Static grid is only used to predict ship hull resistance, and dynamic grid is used to predict ship hull resistance, trim and sinkage. The nominal wake profile and ship wave pattern were observed. The trim and sinkage are very small values, so for their prediction the large error was obtained by using experiment data (such as mass and center of gravity). Through numerical discretization process and when the grid attached to the hull surface, it caused slight deviation between the ship geometries used in CFD simulation and the original IGS file. Furthermore, ship model initial motion and rotation center would be changed. In the end, these reasons cause large error. The study provides the solution of this situation by a XCG (Center of gravity in x direction) correction process. The results of trim and sinkage value were significantly improved.

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