动态失速导致叶片气动载荷急剧变化，造成振动载荷激增，桨叶寿命大幅衰减。针对动态失速问题，从座头鲸胸鳍在动态倾转下取得良好的流动特性获得启示，据此模化出仿生正弦前缘翼面（包含3种波峰和2种波长），旨在实现动态失速控制。借助三维非定常数值模拟方法，采用运动网格技术，基于SC1095旋翼翼型，研究了仿生前缘动态失速流动控制机理及运动参数和来流速度的影响。结果表明：正弦前缘大幅度降低俯仰力矩系数峰值和阻力系数峰值；前缘波峰越大、波长越小，阻力系数峰值与俯仰力矩系数峰值的抑制效果越明显，虽然升力系数峰值减小，但其减小量远小于前两者，例如其中一种仿生翼使俯仰力矩系数峰值减小了47.7%，阻力系数峰值减小了36.4%，升力系数峰值减小14.1%；在最大迎角附近，正弦前缘能够缓和失速特性，使载荷变化更为平缓；在高平均迎角、低俯仰频率、低马赫数下，仿生翼动态失速控制效果更强，相比较而言迎角振幅的影响较小。
Dynamic stall causes dramatic changes in aerodynamic loads of blades, leading to a sharp increase in vibration loads and a significant decrease in blade life. To solve the dynamic stall problem of airfoil, this paper obtains inspiration from the good flow characteristics of humpback whale's pectoral fins under dynamic tilt, and models the bionic sinusoidal leading-edge airfoil (including three peaks and two wavelengths) to suppress dynamic stall. With the help of three-dimensional unsteady numerical simulation method, the control mechanism of bionic leading-edge on dynamic stall and the effects of motion parameters and inflow velocity on SC1095 rotor airfoil are studied by using the moving grid technology. The results show that the peak values of pitch moment coefficient and drag coefficient are reduced greatly by sinusoidal leading-edge. The bigger the wave peak and the smaller the wavelength of the leading-edge, the more obvious the suppression effect of the peak values of drag coefficient and pitch moment coefficient are. Although the peak value of lift coefficient decreases, the reduction is much smaller than that of the former two. For example, for one of the bionic wings, the peak pitch moment coefficient decreases by 47.7%, the peak drag coefficient decreases by 36.4%, whereas the peak lift coefficient decreases by 14.1%. At approximately the maximum angle of attack, the sinusoidal leading-edge can mitigate stall characteristics and make the load change more gently. At higher average angle of attack, low pitch frequency and low Mach number, the dynamic stall control effect of bionic wing is stronger. Comparatively speaking, amplitude of angle of attack matters less.
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