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采用实验测量和数值仿真相结合的方法研究了微型扑旋翼多自由度复杂运动及运动与气动特性之间的相互作用。基于机械式扑旋翼运动模型,使用高速摄影测量和数字图像处理的方法,测量了扑旋翼的运动与变形,并将此结果作为数值仿真的输入,进一步研究了翼的气动特性。结果表明:1)扑旋翼的拍动角近似三角波变化,旋转角随时间线性增加,俯仰角在初始迎角附近波动,并有三个波峰;2)弦向弯曲度的变化规律近似为三角波,沿展向不同位置有相位差异,展向扭转角的变化规律接近于梯形波;3)扑旋翼运动产生的翼尖涡、前缘涡与后缘涡形成了复杂的涡环,涡结构的变化决定了翼的瞬态气动力的产生;4)扑旋翼的柔性变形能够带来平均和峰值升力的提高。
The interaction between the multi-degree-of-freedom complex motion and the motion and aerodynamic characteristics of the micro-flutter was studied by a combination of experimental measurements and numerical simulations. Based on the mechanical flutter motion model, the motion and deformation of the flutter rotor were measured by using high-speed photogrammetry and digital image processing. The results were used as the input of numerical simulation to further study the aerodynamic characteristics of the wing. The results show that: 1) The flutter angle of the flutter rotor is similar to that of the triangular wave. The rotation angle increases linearly with time. The pitch angle fluctuates around the initial attack angle and has three peaks. 2) The phase change of the twist angle is similar to that of the trapezoidal wave. (3) The tip vortex, leading edge vortex and trailing edge vortex formed by the flutter rotor form a complex vortex ring, and the vortex structure changes The transient aerodynamic force of the wing is generated. 4) The flexible deformation of the flutter can bring about average and peak lift.