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Intake Performance Characteristics according to S-duct Cross-section Shape in UAV

무인기 S형 흡기구의 단면 형상에 따른 흡기구 성능 특성

  • Eom, Hee-Ok (Department of Mechanical Engineering, Yonsei University) ;
  • Bae, Ji-Yeul (Department of Mechanical Engineering, Yonsei University) ;
  • Lee, Namkyu (Department of Mechanical Engineering, Yonsei University) ;
  • Kim, Jihyuk (Department of Mechanical Engineering, Yonsei University) ;
  • Nam, Juyeong (Department of Mechanical Engineering, Yonsei University) ;
  • Jo, Hana (Agency for Defense Development) ;
  • Cho, Hyung Hee (Department of Mechanical Engineering, Yonsei University)
  • Received : 2019.05.23
  • Accepted : 2019.08.26
  • Published : 2019.10.01

Abstract

In many military aircraft, s-shaped diffusers are used to prevent the fan blades of the turbofan engine from being exposed to the outside. The inlet configurations of the air intakes for military aircraft vary, such as the rectangular intake of the F-22, the crescent-like intake of the F-16, elliptical intake of the MQ-25. In this study, the aerodynamic performance of s-shaped diffusers with various inlet configurations was evaluated using numerical analysis. In addition, the configuration of the middle section of an s-shape duct was changed to the crescent shape, and the effects on its aerodynamic performance were investigated. As a result, there was a slight difference in total pressure recovery according to various inlet configurations with ellipse-shaped middle sections. Also, the total pressure distortion was the lowest in the rectangular inlet shape. When the configuration of the middle section was changed from an ellipse to a crescent shape, the total pressure recovery remained at a high level, except for the ellipse-shaped inlet configuration. In terms of total pressure distortion, the duct with the crescent-shaped middle section showed a significantly more uniform pressure distribution than that with the ellipse-shaped middle section.

다양한 군용기에서, S자 형상의 디퓨저(흡입구)는 터보팬 엔진의 블레이드가 외부에 노출되는 것을 방지하기 위해 사용된다. 군용 항공기의 흡입구 형상은 F-22와 같은 직사각형, F-16과 같은 초승달모양, MG-25와 같은 타원형 등으로 다양하다. 본 연구에서는 수치해석을 통해 다양한 입구 형상을 갖는 S자 디퓨저의 공력 성능을 평가하였다. 또한, S형 덕트 중단부 단면 형상을 초승달 모양으로 변경하여 공력 성능에 미치는 영향을 분석하였다. 결과적으로, 공력 성능은 다양한 입구 모양에 따라 압력회복률에 약간의 차이를 보였다. 또한 압력왜곡은 직사각형 입구 형태에서 가장 낮았다. 중간단면의 형상이 타원형에서 초승달 모양으로 변경되었을 때, 전체 압력 회복은 높은 수준을 유지했다. 압력왜곡의 경우 초승달 형의 중간 단면을 갖는 덕트가 타원형 중간 단면 덕트보다 균일한 압력 분포를 나타내었다.

Keywords

References

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