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Experimental and Numerical Study on the Structural Stiffness of Composite Rotor Blade

복합재 로터 블레이드의 구조 강성도에 대한 실험적/수치적 연구

  • Jeon, Hyeon-Kyu (Department of Aerospace Engineering, Chungnam National University) ;
  • Jeon, Min-Hyeok (Department of Aerospace Engineering, Chungnam National University) ;
  • Kang, Min-Song (Department of Aerospace Engineering, Chungnam National University) ;
  • Kim, In-Gul (Department of Aerospace Engineering, Chungnam National University) ;
  • Park, Jae-Sang (Department of Aerospace Engineering, Chungnam National University) ;
  • Seok, Jin-Young (Department of Aerospace Engineering, Chungnam National University)
  • Received : 2019.05.09
  • Accepted : 2019.08.26
  • Published : 2019.08.31

Abstract

The basic mechanical properties of helicopter rotor blade are important parameters for the analysis of helicopter performance. However, it is difficult to estimate these properties because the most of rotor blades consist of various materials such as composite materials and metals, etc. In this paper, the bending/torsional stiffness for composite rotor blade of unmanned helicopter were evaluated through experimental and analytical studies. In finite element analysis, the bending/torsional stiffness were evaluated through the relationship of load-displacement and element stiffness matrix. The evaluated stiffness from the measured strains and displacements in bending and torsional test agreed well with the derived results of FEA.

헬리콥터의 주 로터 블레이드는 헬리콥터의 양력과 추력을 발생시키는 구조물로, 헬리콥터의 성능을 좌우하는 중요한 구조 구성품이다. 헬리콥터의 기계적 특성값은 헬리콥터 성능해석 단계에 활용되는 중요한 매개변수이나 대부분의 로터 블레이드는 복합재 등과 같은 여러가지 재료의 조합으로 제작되므로 기계적 특성값을 추정하는 것은 쉽지 않다. 본 논문에서는 유한요소해석과 실험적 방법을 통하여 무인 헬기 복합재 로터 블레이드의 단면별 휘임 및 비틀림 강성도를 취득하였다. 유한요소해석을 통해 요소 강성 행렬과 하중-변위 관계식을 이용하여 단면별 강성도를 계산하였으며, 스트레인 게이지를 이용한 휘임 및 비틀림 시험에서 구한 변형률 값을 이용하여 단면별 강성도를 계산하였다. 유한요소해석으로 계산한 단면별 강성도와 시험 결과를 이용하여 계산한 단면별 강성도가 잘 일치함을 확인하였다.

Keywords

References

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