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

The Korean Society for Aeronautical and Space Sciences (한국항공우주학회)
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An Experimental Study on Blade Deformation of Coaxial Rotor System Using SPR(Stereo Pattern Recognition) Technique

SPR(Stereo Pattern Recognition) 기법을 이용한 동축 로터 블레이드의 변형에 대한 실험적 연구

  • Received : 2020.06.18
  • Accepted : 2020.07.06
  • Published : 2020.08.01
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Abstract

These days, the coaxial rotor system is used for various purposes like UAVs, Mars exploration helicopters, and the next-generation high-speed rotorcraft. A number of research projects on aerodynamic performance of rotor systems, including the coaxial configuration have been made previously. On the contrary, research on rotor blade deformation has been mainly carried out regarding the single rotor system, where such effort has not been enough on the coaxial system. Nonetheless, in case of the coaxial system, blade deformation analysis is much more important because of the complex air flow around the rotors, and that the distance between the two rotors is a key factor affects aerodynamic performance of the entire system. For these reasons, an experimental study on rotor blade deformation of the coaxial system was conducted using the Stereo Pattern Recognition(SPR) technique, one of the state-of-the-art of photogrammetry method. In this research, a small-scale coaxial rotor test stand designed by Korea Aerospace Research Institute(KARI) was used. With the same test stand, performance of the coaxial configuration had been studied before the experimental study on blade deformation, in order to find the relation between performance and blade deformation of the rotor system. Results of the performance test and the deformation study are presented in this article.

동축 로터 시스템은 기존의 헬리콥터뿐만 아니라 드론, PAV, 차세대 고속 회전익기 및 화성탐사용 헬리콥터에 적용되는 등, 활용 분야가 점점 넓어지고 있다. 로터 시스템의 성능 연구는 기존 연구에서 동축 로터를 대상으로도 여러 차례 수행되었으나, 로터 블레이드의 변형에 대한 연구는 주로 단일 로터 시스템만을 대상으로 진행되었다. 하지만 동축 로터 시스템에서는 주변에서 발생하는 유동이 복잡하며, 두 로터의 간격이 로터 시스템 전체의 성능에 주요한 영향을 주므로 블레이드의 변형 연구가 더욱 중요하다. 이에 본 연구에서는 최신식 고속 영상촬영 기법 중 하나인 SPR(Stereo Pattern Recognition) 기법을 사용해 동축 로터 블레이드의 변형 측정에 대한 실험적 연구를 수행하였다. 본 연구에는 한국항공우주연구원에서 개발한 축소 동축 로터 시험장치가 사용되었으며, 로터 블레이드의 변형과 성능의 연관성을 고찰하기 위해 동축 로터 시스템의 성능시험이 선행되었다. 해당 시스템의 로터 블레이드 변형을 SPR 기법으로 측정한 결과는 사전에 진행된 성능시험 결과와 함께 본 논문에 제시되었다.

Keywords

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