尾流飞行风险概率拓扑图的构建方法

考虑尾流遭遇情形下的不确定性与随机性因素，利用蒙特卡洛法对三维空间内的每个尾流遭遇点进行大数据量的仿真实验，提取了尾流遭遇情形下的三维极值参数，验证了一维的极值参数符合广义极值（GEV）分布；提出了三维极值参数的四参数变权重Copula（FPAVW Copula）模型，拟合优度检验的结果表明FPAVW Copula具有比其他Copula更高的精度；利用FPAVW Copula对尾流场内每个网格采样点上的三维极值参数进行了辨识，计算出了尾流空间的风险概率指标分布情况；在此基础上对尾流风险概率拓扑在不同发展阶段的结构特征进行了分析，构建了可视化的二维及三维风险概率结构图，可用来研究尾流场内的风险规避策略及算法.所提方法及思路亦可对其他内外部环境因素影响下的飞行风险概率评估及拓扑结构可视化等热点研究方向提供参考.

Topological space construction of flight risk probabilities during wake encountering

Under the background of increasing wake vortex problems, wake risk probability topology was built using complex human-machine-environment theory and multivariate extreme value theory. First, three-dimensional wake extreme parameters required for assessing the risk were extracted based on Monte Carlo method. And the one-dimensional extreme parameters were verified to meet generalized extreme value (GEV) distribution. Second, the four parameters and adaptive variable weight (FPAVW) Copula was proposed for modeling three-dimensional extreme parameters. The results of fitting test show FPAVW Copula model has higher accuracy than the other models. Third, flight risk probability in each corresponding grid node was evaluated on the basis of using Copula model to describe all the extreme values in three-dimensional wake space. Then the risk's 2D and 3D topological structures at different stages of wake vortex were analyzed. The work is an effective complement to aircraft system safety assessment theory and method, which provides reference for research directions such as wake navigation control, risk aversion, airport safety interval improvement, and environmental risks visualization. It is also suitable for comparative analysis of flight risk probabilities under different circumstances.