旋翼几何参数对共轴双旋翼悬停性能的影响

为研究旋翼几何参数对共轴双旋翼悬停性能的影响,建立了基于自由尾迹法和2阶升力线法的共轴双旋翼气动模型,分别计算和分析了共轴双旋翼的旋翼翼型、上下旋翼半径之比、上下旋翼间距、桨叶扭转角以及桨叶尖削比等参数对共轴双旋翼悬停性能的影响,最后基于分析结果综合优化了悬停状态下各旋翼的几何参数.结果表明:旋翼翼型、上下旋翼间距、桨叶扭转角以及桨叶尖削比对共轴双旋翼悬停性能有一定的影响,上下旋翼间距对其影响较小,综合优化旋翼在拉力系数为0.01时与基准旋翼相比,扭矩系数降低10.5%,悬停效率提高9.5%.

Effect of geometric parameters of rotor on hovering performance of coaxial rotor

To study the effect of geometric parameter on hovering performance of coaxial rotor, the aerodynamic model of coaxial rotor based on free-wake method and second-order lifting-line theory was established, the performance with the rotor's airfoil, the ratio of the upper rotor's radius to the lower rotor's radius, the vertical separation of the rotor, the blade twist angle, and the rotor taper was calculated and analyzed, the comprehensive optimized rotor's geometric parameter was selected and analyzed in hovering based on the upper result at last. The results show that influences of the rotor's airfoil, the ratio of the upper rotor's radius to the lower rotor's radius, the blade twist angle, and the rotor taper are great, while there is almost no influence of the vertical separation on the hovering performance. The tension coefficient of 0.01 of the comprehensive optimized rotor can be reduced by 10.5% and the figure of merit can be increased by 9.5% comparing with the basic rotor.