【作者】 胡添元；

【导师】 余雄庆；

【作者基本信息】 南京航空航天大学 ， 飞行器设计， 2006， 硕士

【摘要】 本文针对飞行器外形隐身优化问题,提出了一种流程简单,可同时优化外形轮廓和剖面形状的二级优化方法,简称二级优化。这种方法将优化的流程分为外形轮廓级和剖面形状级两个层次:外形轮廓级的优化任务是将轮廓外形参数传递给剖面形状级,并对外形轮廓进行优化;剖面形状级的优化任务是对剖面形状进行优化,并将目标函数值返回外形轮廓级。为了减少剖面形状级的分析次数、有利于寻找最优解,采用了基于代理模型的二级优化。二级优化的最终结果可获得最优的轮廓形状和剖面形状。以一个具有低RCS特征的飞行器机身为算例,验证了这种二级优化方法的可行性和有效性。另一方面,本文分析了现有的外形隐身优化中常用的目标函数,在此基础上提出了一种新的目标函数—雷达平均检测概率,并对各种目标函数进行了对比分析。应用二级优化方法和各种目标函数的定义对一个无人作战飞机模型进行外形隐身设计,并讨论了在飞行器外形隐身优化中如何合理选取目标函数的问题。更多还原

【Abstract】 This paper proposes a two-level optimization approach for shape design of low observable aircraft. The approach is simple in terms of flowchart and provides the ability to conduct both the contour and the section optimization simultaneously. The approach is divided into two levels including contour optimization and section optimization: the contour optimization sends the contour parameters to the level of section optimization and its objective is to find the optimum contour; the section optimization is aimed to find the optimum section shape for the given contour parameters and feedback the objective function to the level of contour optimization. This two-level approach is able to find out the optimum shape including both the contour and the section shape. A low radar cross section design optimization problem of a simlpe fuselage shape was used to verify the approach.Also, this thesis investigates two objective functions which are often used in shape optimization of low observable. Based on the analysis, this paper proposes a new objective function-radar average detection probability, and summarizes the characters of objective functions.The two-level optimization approach and the definitions of objective functions were applied to a stealth design for a simplified Unmanned Combat Air Vehicle. The suggestions for the reasonable selection of the objective function in the stealth aircraft design optimization are presented .更多还原