飛機幾何模型適用於FLITE3D之計算

Abstract

在本篇論文中，我們引用了計算幾何原理，其中包含了三次曲線、雙三次曲面以及曲線之連續性來建立完整的商用飛機模型。 在傳統的幾何模型中，較複雜之幾何模型可經由曲面/曲面之相交過程來建立。經由這種特殊的計算需求，在使用FLITE3D之計算時就必須在幾何模型上加入一些限制條件。這些限制條件包含了計算網格生成時對模型資料的適應性與各種形式的邊界條件及定義整個幾何模型的計算領域邊界等。 本篇論文主要的目的是建立飛機幾何模型及求取幾何模型的精確度。精確度包括了扭曲的消除及曲面相交技術。最後，我們必須從幾何模型中所計算出的資料轉換成可用形式的資訊，作為FLITE3D程式計算之準備。

In this article we employ the computational geometry theory, which includes cubic curve, bi-cubic parametric surfaces and the continuity of curve to establish a complete commercial airplane. In traditional geometric modeling, complex geometric models can be constructed via a process of surface/surface intersection. Due to special demands of the computation scheme, more complications are imposed on the geometric model when it is to be used in a FLITE3D computation. Such demands may include adaptivity of the model data structure for computational mesh generation and the imposition of various types of boundary conditions on and around the computational domain boundary formed by the geometric model. The aim of this thesis is to construct a geometric aircraft model and to obtain the accuracy of aircraft modeling. The accuracy includes the elimination of twist and surface/surface intersection technique. And finally, we must prepare the information needed for the computation which are then calculated from the model and translated into a form usable by the FLITE3D program.