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

  • 제50권10호
  • /
  • Pages.677-690
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  • 2022
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  • 1225-1348(pISSN)
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  • 2287-6871(eISSN)
한국항공우주학회 (The Korean Society for Aeronautical and Space Sciences)
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제자리 비행하는 이중 덕트 팬 비행체의 지면 효과에 대한 수치적 연구

Numerical Investigation of Ground Effect of Dual Ducted Fan Aircraft During Hovering Flight

  • Lee, Yujin (Department of Aerospace Engineering, Pusan National University) ;
  • Oh, Sejong (Department of Aerospace Engineering, Pusan National University) ;
  • Park, Donghun (Department of Aerospace Engineering, Pusan National University)
  • 투고 : 2022.01.20
  • 심사 : 2022.08.11
  • 발행 : 2022.10.01
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초록

Actuator disk method 기반의 유동 해석자를 이용하여 수직 이착륙 복합형 비행체 중 하나인 이중 덕트 팬 항공기에 대한 공력해석을 수행하고 관련 지면 효과를 분석하였다. 회전 격자 기법을 이용한 해석결과와의 비교를 통해, 지면 효과 분석을 위한 해석자의 특성과 정확도를 함께 평가하였다. 지면과의 거리에 따른 공력 성능과 유동장 특성을 분석하였다. 지면과의 거리가 가까울수록 팬 추력은 증가하지만, 덕트, 동체, 날개의 수직력 감소로 인한 총 수직력 및 제자리 비행 효율의 저하를 확인하였다. 동체 하부의 유동장 분석으로부터 팬 후류와 지면 간의 상호작용에 의해 발생하는 지면 와류와 분수 유동을 확인하고, 이들이 비행체 공력 성능에 미치는 영향을 분석하였다. 속도 프로파일 비교/검토를 통해 비행체로부터의 거리와 방향에 따른 기체 주변 아웃워시의 강도와 특성을 분석하였다. 또한 콜렉티브 피치각에 따른 지면 효과의 영향을 확인하였다.

By using an actuator disk method based flow solver, aerodynamic analysis is carried out for a dual ducted fan aircraft, which is one of the VTOL compound aircrafts, and its associated ground effect is analyzed. The characteristics and accuracy of the solver for ground effect analysis is evaluated through a comparison with the results obtained from the sliding mesh technique. The aerodynamic performance and flow field characteristics with respect to the distance from the ground are analyzed. As the ground distance decreases, the fan thrust increases, but the deterioration of total normal force and hovering flight efficiency is identified owing to the decrease in the vertical force of the duct, fuselage, and wing. By examining the flow field in the bottom of the fuselage, the ground vortices and fountain flow generated by the interaction of the fan wake and ground are identified, and their influence on the aerodynamic performance is analyzed. The strength and characteristics of outwash with respect to the ground distance and azimuth direction are analyzed through comparison/examination of velocity profile. Influence of the ground effect with respect to collective pitch angle is also identified.

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과제정보

이 논문은 부산대학교 기본연구지원사업(2년)에 의하여 연구되었음

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