飞机总体外形几何性质的快速求值

Algorithm for Computing Characteristic Values of Aircraft Configuration in China

采用了两种快速算法算子和离散算子，提出了一种新的射线法用于点─多面体分类，研究并解决了由多个曲面（或平面）切割另一曲面形成的局部表面面积问题，并推广到求解任意截面面积。同时将飞机外形设计中常见的复杂几何体归类定义，解决了参数化设计中的几何特征值计算这一工程问题，既达到了快速的目的，精度也令人满意。

China needs now an algorithm for rapidly and accurately computing characteristic values of aircraft configuration-areas, volumes. UP to now, manual calculations are very slow and accuracy islow. In the absence of information in the world's open literature, such an algorithm is developed andpresented in this paper.The authors start from surface subdivision algorithm proposed by Lane et al in 1980ill. Eqs.(3)and (4) arc derived by the authors and they serve as the foundation of the authors' algorithm forcomputing characteristic areas of aircraft configuration. Likewise, eq.(6), derived by the authors,leads to the algorithm for computing characteristic volumes of aircraft configuration.The authors'algorithm is very much faster than existing manual procedure. For the tank nearinlet in Fig.3, its volume, enclosed within fuselage surfaces and inlet surfaces,takes less than oneminute to compute on CDC CYBER-830, whereas hours were needed formerly when calculationswere carried out manually. The final iterative result for the volume is within 0.5% of the previousiteration; hence accuracy is quite high.