高速直升机方案中旋翼自转状态的实验研究

Experiment research on the rotor autorotation statefor a high-speed helicopter scheme

近年来对高速直升机的研究日益兴盛起来,而高速直升机设计的关键问题就是升力的转移和过渡。本文利用自转状态在相同临界迎角下可以承担更多升力的特点,提出将自转引入升力转移的过程中,从而达到减小机翼面积、降低机体重量、减小阻力的目的。针对某一高速直升机方案的自转状态,本文设计和建设了试验模型和试验设备,进行了相应的实验研究。通过与直升机正常工作状态下旋翼的实验结果对比,得出了自转旋翼具有更高的效率的结论;并且根据实验结果分析了自转旋翼的稳定转速与前飞速度以及桨盘迎角的关系。通过与前期理论研究的计算结果相比较,对已有的气动模型进行了检验,理论与实验结果得到了相互印证。

Recent years, many projects come out for the goal of high-speed helicopter. However, every one must solve the problem related to stall and shock wave at main rotor blades since that restrict the flight speed of helicopters. Most critical task for these projects is to shift the lift between the main rotor in helicopter mode and the wing in airplane mode back and forth. The state of rotor autorotation is introduced into lift transfer, and therefore the wing area of the high-speed rotorcraft scheme might be reduced, and the structure weight would be smaller and the drag would be decreased. The test model was made and an experiment was done to verify the prediction of the autorotation state characteristics for a high-speed rotorcraft scheme. The conclusion is that the autorotation rotor has better aerodynamic performance and higher efficiency comparing with the powered rotor of helicopters. The relations among steady rotary speed, forward speed and rotor disk angle of attack were established from both the experiment and analysis.