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旋翼的尾迹流强烈地影响旋翼桨叶的空气动力分布。适当地描述尾迹流的几何形态显得非常重要。本文从不可压缩流的三元拉普拉斯方程出发,采用一种称为“旋翼起转法”(即时间t=0时,旋翼静止,经过△t,旋翼以角速度Ω旋转,以V_f等速前飞)逐步迭代计算,求出每次时间间隔的桨叶环量,从而求出被离散化的尾涡线位置(即尾迹位置)。计算一直进行到尾迹运动的稳定,然后用“修正”的薄翼理论和全攻角范围的实验升、阻力系数,求出桨叶的载荷和弹性响应。计算中采用有实测数据可供比较的H-34机作为算例。并将前四阶计算结果与实测结果进行比较。比较结果表明,二者规律一致,数量级也接近,误差小于其它方法。
The wake of the rotor strongly influences the aerodynamic profile of the rotor blades. Appropriately describing the wake geometry is of great importance. In this paper, starting from the incompressible ternary Laplacian equation, we use a method called “rotor spin-up” (ie rotor is stationary at time t = 0, after Δt, rotor rotates at angular velocity Ω, V_f, etc. Fast forward flight) iterative calculation step by step, calculate the blade ring volume per time interval, so as to find the discretized position of the rear vortex line (ie wake position). The calculation is carried out until the stability of the wake movement, and then use the “modified” thin wing theory and the range of full angle of attack of the experimental lift and drag coefficient, to obtain blade load and elastic response. The calculation uses the H-34 with the measured data for comparison as an example. The results of the first four steps are compared with the measured results. The comparison results show that the two laws are consistent and the order of magnitude is close, the error is less than other methods.