Changes in flight stability characteristics at the advanced stage of aircraft design are complex and require thorough investigations. This paper examines the impact of wing strake modification on high-performance aircraft using computational fluid dynamics (CFD). The dynamic behaviour is calculated using the forced oscillation technique, while the effect of geometric variation on longitudinal stability characteristics is extensively studied. Steady-state experimental data is utilised to validate the computational setup. Static aerodynamic coefficients, dynamic stability derivatives and the positions of aerodynamic and pressure centres are employed to quantify the changes. Furthermore, the alterations in stability characteristics are correlated with flow physics. The results indicate a reduction in longitudinal static and dynamic stability at various flight conditions due to the proposed modification. This deliberate reduction was necessary to accommodate the installation of a fly-by-wire system. The discussed design changes have been effectively implemented on an in-service aircraft.

中文翻译：

---

通过机翼板条修改改变高性能飞机的飞行稳定性特性

飞机设计后期飞行稳定性特性的变化是复杂的，需要进行彻底的研究。本文利用计算流体动力学 (CFD) 研究了机翼板条修改对高性能飞机的影响。使用受迫振动技术计算动态行为，同时广泛研究几何变化对纵向稳定性特性的影响。利用稳态实验数据来验证计算设置。采用静态空气动力系数、动态稳定性导数以及空气动力和压力中心的位置来量化变化。此外，稳定性特性的变化与流动物理学相关。结果表明，由于所提出的修改，各种飞行条件下的纵向静态和动态稳定性有所降低。为了适应电传操纵系统的安装，这种有意的减少是必要的。所讨论的设计变更已在现役飞机上有效实施。