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Vibratory Loads Behavior of a Rotor in High Advance Ratios

고속 전진비 조건에서의 로터 진동하중 특성 연구

  • Na, Deok Hwan (Department of Aerospace Information Engineering, Konkuk University) ;
  • You, Younghyun (Department of Aerospace Information Engineering, Konkuk University) ;
  • Jung, Sung Nam (Department of Aerospace Information Engineering, Konkuk University)
  • Received : 2017.09.01
  • Accepted : 2018.01.18
  • Published : 2018.03.01

Abstract

In this study, the hub vibration load characteristic is evaluated for a rotor in high advance ratio conditions while investigating blade loads through the structural load prediction and harmonic analysis. Numerical studies are performed to validate the wind tunnel test data performed in NASA as the rotor advance ratios are varied from 0.40 to 0.71. A good correlation is obtained for rotor performance calculation at the range of advance ratios considered. It is observed that the hub vibration loads remain almost unchanged when the advance ratios are higher than 0.5, even though the amplitudes of blade structural loads become larger with increasing advance ratios. A harmonic analysis on blade moments is confirmed that the dominant structural mode is 3/rev component for flap bending moments and 4/rev for lag bending moments. The reason is due to the tendency of the second flap and lag mode frequencies which approach 3/rev and 4/rev, respectively, as the advance ratios are increased.

Acknowledgement

Grant : 소형무장헬기 연계 민수헬기 국제공동 체계개발과제

Supported by : 산업기술평가관리원(KEIT)

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