飞机大迎角俯仰运动下的横侧向气动特性及被动控制

Lateral-Direction Aerodynamic Characteristics and Forebody Strake Control of an Aircraft Undergoing Pitching Oscillation on High Attack Angle

在南航3m低速风洞内,利用一套两自由度动态试验机构,通过测力实验研究了某飞机模型静态和俯仰动态过程中大迎角下的横侧向气动特性,分析比较了在模型头部加上扰动片后,对横侧向气动特性产生的影响。研究结果表明,模型在静态大迎角下会产生较大的侧向力和偏航力矩,而模型的快速上仰过程则进一步加剧了模型头部流动的非对称性,在大迎角下产生较大的偏航力矩迟滞环;当在模型头部加扰动片后,不论是静态过程还是动态过程,都使得模型的侧向力和偏航力矩减小,从而改善了俯仰运动过程中大迎角下的横侧向气动特性。

Lateral-direction aerodynamic characteristics of an aircraft in static and high attack angle pitching oscillation dynamic process were experimentally investigated in a 3m low speed wind tunnel in NUAA by using a set of two-freedom dynamic test apparatus. Effects of forebody strake on lateraldirection aerodynamic characteristics were also analyzed. Results show that the side force and yawing moment under static high angle of attack condition are very large due to the forebody asymmetric vortex. In quick high attack angle pitching-up motion, this force and moment increase further. When forebody strake is mounted at aircraft nose tip, side force and moment are suppressed effectively in high attack angles condition not only in static test but also in dynamic test. So lateral-direction aerodynamic characteristics are improved.