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

The Korean Society for Aeronautical and Space Sciences (한국항공우주학회)
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Fatigue Safe Life Analysis of Helicopter Bearingless Rotor Hub Composite Flexbeam

헬리콥터 무베어링 로터 허브 복합재 유연보 피로 안전수명 해석

  • Kim, Taejoo (Rotorcraft Technology Division Rotor Department, Korea Aerospace Research Institute) ;
  • Kee, Youngjoong (Rotorcraft Technology Division Rotor Department, Korea Aerospace Research Institute) ;
  • Kim, Deog-Kwan (Rotorcraft Technology Division Rotor Department, Korea Aerospace Research Institute) ;
  • Kim, Seung-Ho (Rotorcraft Technology Division Rotor Department, Korea Aerospace Research Institute)
  • Received : 2013.04.05
  • Accepted : 2013.06.13
  • Published : 2013.07.01
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Abstract

After we designed Bearingless rotor hub system for 7,000lb class helicopter, flexbeam fatigue analysis was conducted for validation of requirement life time 8,000 hours. sectional structural analysis method applying elastic beam model was used. Fatigue analysis for two sections of flexbeam which were expected to weak to fatigue damage from result of static analysis was conducted. Extension, bending and torsion stiffness of flexbeam section shape was calculated using VABS for structure analysis. S-N curve of two composite material which composed flexbeam was generated using wohler equation. Load analysis of bearingless rotor system was conducted using CAMRAD II and load analysis result was applied HELIX/FELIX standard load spectrum to generate bearingless rotor system load spectrum which was used flexbeam fatigue safe life analysis.

7,000lb 급 헬리콥터를 위한 무베어링 로터 허브 시스템을 설계한 후, 무베어링 로터 허브 시스템의 주요 구성품 중 하나인 유연보에 대해 요구수명 8,000시간을 만족하는지 확인하기 위한 피로해석을 수행하였다. 2차원 탄성 보 모델에 대한 단면 구조해석 방법을 적용하였으며, 정적구조해석을 통해 피로손상에 취약할 것으로 예상되는 두 단면에 대한 피로해석을 수행하였다. 구조해석을 위해 VABS를 사용하여 유연보 단면 형상에 대한 인장, 굽힘 및 뒤틀림 강성을 계산하였고, wohler equation을 적용하여 유연보를 구성하는 두 가지 복합재 소재에 대한 S-N 곡선을 생성하였다. CAMRAD II를 통해 무베어링 로터 시스템의 하중해석을 수행하였으며, 하중해석 결과를 HELIX/FELIX 표준하중 스펙트럼에 적용하여 무베어링 로터 시스템의 하중 스펙트럼을 생성한 후, 이를 통해 피로해석을 수행하였다.

Keywords

References

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  1. Dynamic Characteristics of Helicopter Bearingless Main Rotor vol.44, pp.5, 2016, https://doi.org/10.5139/JKSAS.2016.44.5.439