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http://dx.doi.org/10.5050/KSNVE.2012.22.4.352

Ground Resonance Instabilities Analysis of a Bearingless Helicopter Main Rotor  

Yun, Chul-Yong (한국항공우주연구원 회전익기술팀)
Kee, Young-Jung (한국항공우주연구원 회전익기술팀)
Kim, Tae-Joo (한국항공우주연구원 회전익기술팀)
Kim, Deog-Kwan (한국항공우주연구원 회전익기술팀)
Kim, Seung-Ho (한국항공우주연구원 회전익기술팀)
Publication Information
Transactions of the Korean Society for Noise and Vibration Engineering / v.22, no.4, 2012 , pp. 352-357 More about this Journal
Abstract
The ground resonance instability of a helicopter with bearingless main rotor hub were investigated. The ground resonance instability is caused by an interaction between the blade lag motion and hub inplane motion. This instability occurs when the helicopter is on the ground and is important for soft-inplane rotors where the rotating lag mode frequency is less than the rotor rotational speed. For the analysis, the bearingless rotor was composed of blades, flexbeam, torque tube, damper, shear restrainer, and pitch links. The fuselage was modeled as a mass-damper-spring system having natural frequencies in roll and pitch motions. The rotor-fuselage coupling equations are derived in non-rotating frame to consider the rotor and fuselage equations in the same frame. The ground resonance instabilities for three cases where are without lead-lag damper and fuselage damping, with lead-lag damper and without fuselage damping, and finally with lead-lag damper and fuselage damping. There is no ground resonance instability in the only rotor-fuselage configuration with lead-lag damper and fuselage damping.
Keywords
Bearingless Main Rotor; Ground Resonance; Fuselage-rotor Coupling; Lead-lag Damper;
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  • Reference
1 Helmut, H., 1992, Will Rotor Hubs Lose Their Bearings, A Survey of Bearingless Main Rotor Development, The 18th European Rotorcraft Forum.
2 Wayne, J,, 1985, Recent Developments in the Dynamics of Advanced Rotor Systems, NASA TM-86669.
3 Song, K. W., Kim, J. H., Kim, S. H., Lee, J. D. and Rhee, W., 2006, An Experimental Investigation of the Aeroelastic Stability of Next-generation Blade for Helicopter, Transactions of the Korean Society for Noise and Vibration Engineering, Vol. 16, No. 8, pp. 848-856.   DOI
4 Weller, W. H. and Peterson, R. L., 1984, Inplane Stability Characteristics for an Advanced Bearingless Main Rotor Model, Journal of the American Helicopter Society, Vol. 29, No. 3, pp. 45-53.   DOI   ScienceOn
5 Weller, W. H., 1990, Relative Aeromechanical Stability Characteristics for Hingeless and Bearingless Rotors, Journal of the American Helicopter Society, Vol. 35, No. 3, pp. 68-77.   DOI
6 Jang, J. and Chopra, I., 1988, Ground and Air Resonance of an Advanced Bearingless Rotor in Hover, Journal of the American Helicopter Society, Vol. 33, No. 3, pp. 20-29.   DOI   ScienceOn
7 Han, C. H., Yun, C. H., Kim, S. J. and Jung, S. N., 2003, Aeromechanical Stability Investigation of a Composite Hingeless Rotor in Hover, Journal of the American Helicopter Society, Vol. 48, No. 3, pp. 159-166.   DOI   ScienceOn
8 Park, J. K., Kim, S. H., Kwak, D. I. and Lee, B. W., 2007, Ground Resonance Analysis for the Class of Korean Utility Helicopter, Proceedings of the KSAS Annual Spring Conference, pp. 890-893.
9 Wayne, J., 1980, Helicopter Theory, Princeton University Press, New Jersey.