Optimization of aerodynamic performance for co-axial rotors with different rotor spacings
Optimization of aerodynamic performance for co-axial rotors with different rotor spacings
复制标题
不同转子间距同轴转子气动性能优化
DOI：
10.1177/1756829318804763
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发表时间：
2018-12-01
影响因子：
1.4
通讯作者：
Wang, Changwei
中科院分区：
文献类型：
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作者：
Lei, Yao;Ji, Yuxia;Wang, Changwei
本文对不同间距的共轴式旋翼悬停时的气动性能进行了研究。采用定制设计的具有7个旋翼间距（z/D= 0.16、0.19、0.23、0.26、0.29、0.33和0.38）的实验平台来测量悬停性能，即共轴推力和功率消耗，并优化共轴系统的气动配置。用“Kline-McClintock方程”计算的推力系数、功率系数和功率载荷的实验误差小于2%。此外，通过数值模拟得到了不同桨距下的流线分布和叶尖压力分布，直观地显示了上下桨气动干扰的影响。结果表明，在特定的转子结构和转速范围内，改变转子间距确实可以改善共轴式旋翼的气动性能，当转子间距为0.19时，共轴式旋翼的气动性能最优。此外，与轴向分离距离相关的气动干扰的大小已被证明对总推力和功率消耗是有益的。对于相同的盘负载，转速的降低导致功率负载的增加，特别是对于z/D= 0.19。还发现，底部转子确实影响顶部转子的性能，在较小的转子间距，而效果显着减少，作为转子间距的增加。
In this article, attempts are made to study the aerodynamic performance of co-axial rotors with different rotor spacings in hover. A custom-designed experimental platform with seven rotor spacings (z/D= 0.16, 0.19, 0.23, 0.26, 0.29, 0.33 and 0.38) is applied to measure the hover performance, i.e. co-axial thrust and power consumption, and to optimize the aerodynamic configuration of the co-axial system. The experimental errors in thrust coefficient, power coefficient and power loading calculated through ‘Kline-McClintock equation’ are less than 2%. Additionally, the streamline distribution and pressure of blade tip at different rotor spacings obtained from numerical simulations are presented to visualize the effects of aerodynamic interference between the top and bottom rotor. Results show that the aerodynamic performance of a co-axial rotor with the specific rotor configure and speed range can be indeed improved by changing the rotor spacing, and the optimal performance is obtained with a rotor spacing of 0.19. Also, the magnitude of aerodynamic interference related to the axial separation distance has demonstrated to be beneficial on the total thrust and power consumption. For the same disc loading, a decrease in rotational speed results in an increase in power loading especially forz/D= 0.19. It is also found that the bottom rotor does affect the performance of the top rotor at smaller rotor spacings, whereas the effect is significantly reduced as the rotor spacing increases.