ACTA AERONAUTICAET ASTRONAUTICA SINICA >
Study on the Performance and Trim of Helicopters with Variable Speed Rotors
Received date: 2012-07-02
Revised date: 2012-09-26
Online published: 2012-10-29
Supported by
Aeronautical Science Foundation of China (2011ZA52004); Foundation of National Key Laboratory of Helicopter Aeromechanics (9140C400601120C4001); New Faculty Foundation of Nanjing University of Aeronautics and Astronautics(56YAH11012)
To investigate the performance and trim characteristics of helicopters with variable speed rotors, this paper makes a study of the rotor power with variable rotor speed, forward speed, helicopter weight and fight altitude as well as the pitch controls and tilt of rotor shaft with respect to rotor speed and forward speed based on a comprehensive rotor modeling. The results indicate that significant power reduction is achieved by the reduction of rotor speed, which can be utilized to improve the endurance, range and flight altitude of helicopters. The variation of rotor speed has significant influence on the trim of helicopters. The trim limits the rotor working at very low rotor speeds,which may incur the increase of the rotor power. The collective and cyclic pitches increase with decreasing rotor speed. The variation of the longitudinal tilt of the rotor shaft with rotor speed is not obvious, and the lateral tilt decreases with decreasing rotor speed.
Key words： helicopter; rotor; variable speed; power; trim
HAN Dong . Study on the Performance and Trim of Helicopters with Variable Speed Rotors[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2013 , 34(6) : 1241 -1248 . DOI: 10.7527/S1000-6893.2013.0228
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