한국항공우주학회지 (Journal of the Korean Society for Aeronautical & Space Sciences)

  • 제46권3호
  • /
  • Pages.237-243
  • /
  • 2018
  • /
  • 1225-1348(pISSN)
  • /
  • 2287-6871(eISSN)
한국항공우주학회 (The Korean Society for Aeronautical and Space Sciences)
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고속 전진비 조건에서의 로터 진동하중 특성 연구

Vibratory Loads Behavior of a Rotor in High Advance Ratios

  • 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)
  • 투고 : 2017.09.01
  • 심사 : 2018.01.18
  • 발행 : 2018.03.01
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초록

본 연구에서는 고 전진비 조건의 로터에 대해 전진비 변화에 따른 허브 진동하중의 변화를 예측하고, 블레이드에서 발생하는 구조하중 예측 및 조화 분석을 통하여 구조하중 변화를 고찰하였다. 로터 전진비는 0.40부터 0.71까지 범위를 가지며, NASA에서 수행한 풍동시험 결과에 대해 수치묘사 연구를 수행하였다. 검증한 결과를 토대로 허브 진동하중 및 블레이드 모멘트를 예측하였다. 허브 진동하중은 최초에 증가하다가 전진비가 0.5 이상의 경우에는 변화가 거의 없음을 보여주었다. 블레이드 구조하중은 전진비가 증가할수록 진폭의 크기가 증가하며, 블레이드 모멘트의 조화 분석을 수행한 결과 플랩 모멘트는 3/rev, 래그모멘트는 4/rev의 영향이 매우 크다는 점을 확인하였다. 이는 전진비가 증가할수록 2차 플랩과 2차 래그 모드의 고유진동수가 각각 3/rev와 4/rev에 근접하기 때문인 것으로 파악되었다.

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.

키워드

참고문헌

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