基于S-ALE流固耦合方法的飞机水上迫降动力学数值分析

Numerical analysis of aircraft dynamic behavior in ditching based on S-ALE fluid-structure interaction method

对飞机水上迫降数值分析而言,结构与流体耦合作用方式是水上迫降研究的核心问题,在一定程度上决定了数值分析的成败。一种基于结构化任意拉格朗日-欧拉算法(S-ALE)的耦合方法用于刻画水上迫降过程中的飞机与水的相互作用。采用S-ALE流固耦合方法开展了飞机水上迫降动力学分析,提取飞机的俯仰姿态和过载的变化规律,并与传统的ALE罚函数耦合方法以及相关实验结果进行对比。结果显示:相对于传统的ALE罚函数耦合方法,S-ALE流固耦合方法较好地避免了流体的渗漏,能够有效预测飞机的二次抬头现象。与实验对比,S-ALE流固耦合方法所预测到的俯仰姿态角和过载曲线与实验数据基本吻合。

For the numerical analysis of aircraft dynamic behavior in ditching,how to define the coupling effect between fluid and structure is the key problem,which determines the success or failure of the numerical analysis to some extent.A coupling method based on structural-arbitrary Lagrangian-Euler algorithm(S-ALE)was used to characterize the interaction between the aircraft and the water during the ditching.S-ALE fluid-structure interaction method was adopted to analyze the dynamical behavior of aircraft in ditching to extract the history of aircraft pitch attitude and overload,and the results were compared with those obtained by the traditional ALE penalty-based coupling method and experiments.It is shown that the S-ALE fluid-structure interaction method can prevent the fluid leakage and effectively predict the phenomenon of aircraft secondary rise,and the pitch attitude angle and overload curve predicted by the S-ALE fluid-structure interaction method are basically consistent with the experimental data.