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Experimental Study on Lift Characteristics Considering Moving Ground Effects of Low Aspect Ratio Wings for Wing-In Ground Effect Crafts

이동지면 효과를 고려한 위그선용 저 종횡비 날개의 양력특성에 대한 실험연구

  • Ahn, Byoung-Kwon (Department of Naval Architecture and Ocean Engineering, Chungnam National University) ;
  • Koo, Sung-Phil (Department of Naval Architecture and Ocean Engineering, Chungnam National University) ;
  • Lew, Jae-Moon (Department of Naval Architecture and Ocean Engineering, Chungnam National University) ;
  • Nho, In-Sik (Department of Naval Architecture and Ocean Engineering, Chungnam National University)
  • 안병권 (충남대학교 선박해양공학과) ;
  • 구성필 (충남대학교 선박해양공학과) ;
  • 류재문 (충남대학교 선박해양공학과) ;
  • 노인식 (충남대학교 선박해양공학과)
  • Received : 2011.03.04
  • Accepted : 2011.06.29
  • Published : 2011.10.20

Abstract

In this study, we are focusing our attention on lift characteristics of the low aspect wings for Wing-In Ground effect crafts (WIG). Experimental measurements at an open-type wind tunnel are carried out and results are comparatively presented. In order to simulate the realistic ground condition in where the WIG craft is flying, moving ground is implemented by a conveyor belt rotating with the same velocity of the inflow. We consider two different wings (NACA0012 and DHMTU section) which have four different aspect ratios (0.5, 1.0, 1.5 and 2.0). Forces acting on the wings are measured and lift characteristics are elaborately investigated for various different conditions. In addition, end-plate effects are estimated. Results are validated by comparing with theoretic solutions of the symmetric airfoil. Present results show that ground effects are differently generated in moving or fixed ground conditions, and hence left characteristics are affected by the ground condition. Consequently, accurate aerodynamic forces acting on the WIG craft are guaranteed in a realistic moving ground condition.

Keywords

References

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