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

The Korean Society for Aeronautical and Space Sciences (한국항공우주학회)
권호 표지
DOI QR코드

DOI QR Code

Static Aeroelastic Analysis of Hingeless Rotor System in Hover Using Free-Wake Method

자유후류기법을 이용한 무힌지 로터 시스템의 정지비행시 정적 공탄성 해석

  • 유승재 (한국과학기술원 항공우주공학과 대학원) ;
  • 임인규 (한국과학기술원 항공우주공학과 대학원) ;
  • 이인 (한국과학기술원 항공우주공학과) ;
  • 김도형 (한국항공우주연구원) ;
  • 김덕관 (한국항공우주연구원)
  • Published : 2008.02.29
Download PDF
⟨ Previous Next ⟩

Abstract

The static aeroelastic analysis of composite hingeless rotor blades in hover was performed using free-wake method. Large deflection beam theory was applied to analyze blade motions as a one-dimension beam. Anisotropic beam theory was applied to perform a cross-sectional analysis for composite rotor blades. Aerodynamic loads were calculated through a three-dimensional aerodynamic model which is based on the unsteady vortex lattice method. The wake geometry in hover was described using a time-marching free-wake method. Numerical results of the steady-state deflections for the composite hingeless rotor blades were presented and compared with those results based on two-dimensional quasi-steady strip theory and prescribed wake method. It was shown that wakes affect the steady-state deflections.

본 연구에서는 자유후류기법을 이용하여 복합재 무힌지 로터 블레이드에 대한 정적 공탄성 해석을 수행하였다. 1차원 보의 거동을 해석하기 위하여 대변형 보 이론이 적용되었다. 또한, 복합재 블레이드의 단면 해석을 위하여 이방성 보 이론이 적용되었다. 공탄성 해석에 필요한 공력 하중들은 와류격자법(VLM)에 기초한 3차원 공기력 모델을 통하여 계산되었다. 이때, 정지비행시의 후류는 순차적 시간 적분 자유후류법을 통하여 묘사되었다. 복합재 무힌지 로터 블레이드의 정적 변형에 대한 해석 결과를 2차원 준정상 공기력과 경험후류기법을 통한 해석 결과들과 비교하여 살펴보았다. 결과적으로, 정지비행시 후류 효과에 의해 정적 변형의 결과가 달라짐을 확인하였다.

Keywords

References

  1. Hodges, D.H., "Nonlinear Equations for the Dynamics of Pretwisted Beams Undergoing Small and Large Rotations", NASA TP-2470, 1985
  2. Bauchau, O.A. and Hong, C.H., "Nonlinear Composite Beam Theory", ASME Journal of Applied Mechanics, Vol. 55, 1988, pp.156-163 https://doi.org/10.1115/1.3173622
  3. Cho, M.H., "Aeroelastic Analysis of Hingeless Rotor Blades Using Refined Structural and Aerodynamic Models", Doctor's Thesis, KAIST, 1994
  4. Atilgan, A.R. and Hodges, D.H., "Unified Nonlinear Analysis for Nonhomogeneous Anisotropic Beams with Closed Sections", AIAA Journal, Vol.29, No.11, 1991, pp.1990-1999 https://doi.org/10.2514/3.10829
  5. Jeon, S.M., Cho, M.H. and Lee, I.,"Static and Dynamic Analysis of Composite Box Beams Using Large Deflection Theory", Computer and Structures, Vol. 57, 1988, pp. 156-163
  6. Landgrebe, A.J., "The Wake Geometry of a Hovering Helicopter Rotor and its Influence on Rotor Performance", the 28th Annual National Forum of the American Helicopter Society, May 1972, pp. 3-15
  7. Kocurek, J.D. and Tangler, J.L., "A Prescribed Wake Lifting Surface Hover Performance Analysis", the 32nd Annual National Forum of the American Helicopter Society, May 1976, pp.24-35
  8. Muller, R. H.G., "Special Vortices at a Helicopter Rotor Blade", Journal of the American Helicopter Society, Vol. 35, October 1990, pp.16-21 https://doi.org/10.4050/JAHS.35.16
  9. Kim, J.M., Komerath, N. M. and Liou, S. G., "Vorticity Concentration at the Edge of the Inboard Vortex Sheet", Journal of the American Helicopter Society, Vol. 39, No. 2, April 1994, pp.30-34 https://doi.org/10.4050/JAHS.39.30
  10. Clark, D.R. and Leiper, A.C., "The Free Wake Analysis; a Method for the Prediction of Helicopter Rotor Hoving Performance", the 25th Annual National Forum of the American Helicopter Society, May 1969, pp.3-11
  11. Scully, M.P., "Computation of Helicopter Rotor Wake Geometry and Its Influence on Rotor Harmonic Airloads", MIT ASRL TR 178-1, March 1975
  12. Lee, D.J. and Na, S.U., "Numerical Simulations of Wake Structure Generated by Rotating Blades Using a Time Marching, Free Vortex Blob Method", European Journal of Mechanics-B/Fluids, Vol.18, No. 1, 1999
  13. Caradona, F.X., and Tung, C., "Experimental and Analytical Studies of a Helicopter Rotor in Hover", NASA TM-81232, 1981
  14. Cho, B.G., "Aeroelastic Analysis of Composite Hingeless Rotor Blades in Hover Using 3-D Aerodynamics", Master's Thesis, KAIST, 2002

Cited by

  1. Aeroelastic Analysis of Rotorcraft in Forward Flight Using Dynamic Inflow Model vol.39, pp.4, 2011, https://doi.org/10.5139/JKSAS.2011.39.4.297