### 重型直升机飞行动力学刚弹耦合建模及空中共振稳定性分析

1. 南京航空航天大学 航空学院 直升机旋翼动力学国家级重点实验室, 南京 210016
• 收稿日期:2020-08-13 修回日期:2020-09-06 发布日期:2020-10-10
• 通讯作者: 陈仁良 E-mail:crlae@nuaa.edu.cn
• 基金资助:
国家自然科学基金（11672128）；江苏高校优势学科建设工程资助项目

### Rigid-elastic coupled flight dynamic modeling and air resonance stability analysis for heavy lift helicopter

WANG Luofeng, CHEN Renliang

1. National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics, College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
• Received:2020-08-13 Revised:2020-09-06 Published:2020-10-10
• Supported by:
National Natural Science Foundation of China (11672128); Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions

Abstract: This paper presents a rigid-elastic coupled flight dynamic modeling method for a Heavy Lift Helicopter (HLH), considering the inherent characteristics of heavy weight and slow rotational speed. The method bridges flight dynamics and coupled rotor-fuselage aeroelastic dynamics, expanding the interested range of frequency to 5 Hz with an additional consideration of the elastic fuselage and blades. Based on the impedance matching method, explicit coupled dynamic equations were derived to simulate the helicopter aeroelastic characteristics in real flight. Finally, this model was used to calculate and analyze the flight and air resonance characteristics for an example HLH in hover. The results show that rotor-fuselage coupling causes the progressive lag mode and fuselage bending mode to approach each other and then separate after arriving at the same point with the increase of the rotational speed, which might result in high frequency transient vibration. The regressive lag mode is unstable without sufficient lag damping; however, with the increase of equivalent lag damping, the second order periodic lag mode will be coupled with the fuselage bending mode. The blade elastic modes are coupled with the fuselage bending mode and the collective flap mode without obvious instability.