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跨声速抖振直接影响飞机结构强度和疲劳寿命,易引发飞行事故。对于刚性静止翼型,其跨声速抖振特性仅与来流状态参数(马赫数、迎角和雷诺数)有关。该文通过释放翼型的俯仰自由度,采用非定常雷诺平均N-S方程建立了流场和结构的耦合求解方法,研究翼型结构弹性特征对跨声速抖振始发边界的影响。研究发现,结构固有频率对弹性支撑翼型的抖振边界影响较大,系统会在更小的来流迎角下失稳;而质量比对抖振边界影响较小。弹性支撑翼型的抖振始发迎角较刚性静止翼型的抖振起始迎角降低了近1°,因此翼型的弹性特征是跨声速抖振研究的重要因素。
Chattering vibration across the aircraft directly affects the strength and fatigue life of the aircraft, easily lead to flight accidents. For rigid stationary airfoils, the transonic vibrational characteristics are only related to the incoming flow parameters (Mach number, angle of attack and Reynolds number). In this paper, by coupling the unsteady Reynolds averaged N-S equation with the freedom of pitch of the airfoil, a coupling solution of the flow field and the structure is established to study the influence of the airfoil structural flexibility on the onset boundary of the transonic chattering. It is found that the natural frequency of structure has a great influence on the buffeting boundary of the elastic supporting airfoil, and the system will be instable at a smaller angle of attack. The mass ratio has little effect on the buffeting boundary. The starting angle of attack of the flexible supporting airfoil is about 1 ° lower than that of the rigid stationary airfoil. Therefore, the elastic characteristics of the airfoil are the important factors in the study of transonic sound buffeting.