Journal of the Korea Institute of Military Science and Technology (한국군사과학기술학회지)

The Korea Institute of Military Science and Technology (한국군사과학기술학회)
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Performance and Airloads Analyses for a Rigid Coaxial Rotor of High-Speed Compound Unmanned Rotorcrafts

고속 비행 복합형 무인 회전익기의 강체 동축반전 로터의 성능 및 공력 하중 해석

  • Kwon, Young-Min (Department of Aerospace Engineering, Chungnam National University) ;
  • Park, Jae-Sang (Department of Aerospace Engineering, Chungnam National University)
  • 권영민 (충남대학교 항공우주공학과) ;
  • 박재상 (충남대학교 항공우주공학과)
  • Received : 2020.03.15
  • Accepted : 2020.06.12
  • Published : 2020.08.05
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Abstract

This study investigates the performance and blade airloads for a rigid coaxial rotor of high-speed compound unmanned rotorcrafts. The present compound unmanned rotorcraft uses not only a rigid coaxial rotor, but also wings and propellers for high-speed flights. For the rigid coaxial rotor in this work, CAMRAD II, a rotorcraft comprehensive analysis code, is used to study the performance at a flight speed of up to 250 knots and blade section lift forces at 230 knots. As the flight speed increases, the rotor power decreases; however, the power of propellers increases to overcome the drag force of a rotorcraft in high-speed flight. The effective lift-to-drag ratio of a rotor has the maximum value of about 11.6 which is much higher than the value of the conventional helicopter. The blade section lift forces of the upper and lower rotors at 230 knots show the similar variation trends for one rotor revolution, and the impulses because of the aerodynamic interaction between both rotors are observed.

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References

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