雷诺数效应对翼型抖振特性的影响

飞行器抖振是一种非线性气动弹性问题,当飞行器进入抖振阶段时,将会对飞行器的性能产生严重影响。而在跨声速条件下,激波附面层相互作用会诱导机翼抖振。本文开展了跨声速条件下翼型抖振特性雷诺数效应的实验研究,揭示了翼型跨声速抖振起始迎角、激波运动前缘边界、频谱特性、抖振频率与雷诺数变化的基本规律。结论如下:雷诺数变化会导致抖振起始边界的改变,对抖振起始迎角下的功率谱密度峰值有明显影响;随着雷诺数的增大,激波运动的前缘后移。雷诺数变化对抖振频率有明显影响,随着马赫数增大,雷诺数效应增强。

On the Influence of Reynolds Number on Airfoil Buffet Characteristics

Aircraft buffeting is a kind of nonlinear aeroelastic issue. Maneuver ability of aircraft will be extremely affected when aircraft buffeting appears. Under transonic condition, the interaction of shock wave boundary-layers may induce wing buffeting. In this paper, an experimental investigation on the effect of Reynolds number on airfoil buffet characteristics was carried out under transonic-flow condition to reveal the influence of Reynolds number on the buffet onset angle of attack, the leading edge of shock movement, the frequency spectrum characteristics and the buffet frequency. Results show that the variation of Reynolds number may lead to the change of buffeting initial boundary, and produce significant effect on power spectral density peak value at the initial angle of attack. Along with the increase of Reynolds number, the attack angle of buffet onset changes slightly, the peak value of power spectral density varies significantly, and the leading edge of moving shock moves backward. The effect of Reynolds number on the buffet frequency is obvious. Along with the increase of Mach number, the effect of Reynolds number becomes larger.