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Experimental Study on the Vortical Flow Behind 2-D Blade with the Variation of Trailing Edge Shape

2차원 날개 끝단 형상에 따른 후류 보오텍스 유동 변화에 대한 실험 연구

  • Paik, Bu-Geun (Maritime & Ocean Engineering Research Institute, KORDI) ;
  • Kim, Ki-Sup (Maritime & Ocean Engineering Research Institute, KORDI) ;
  • Moon, Il-Sung (Maritime & Ocean Engineering Research Institute, KORDI) ;
  • Ahn, Jong-Woo (Maritime & Ocean Engineering Research Institute, KORDI)
  • 백부근 (한국해양연구원 해양시스템안전연구소) ;
  • 김기섭 (한국해양연구원 해양시스템안전연구소) ;
  • 문일성 (한국해양연구원 해양시스템안전연구소) ;
  • 안종우 (한국해양연구원 해양시스템안전연구소)
  • Received : 2010.10.13
  • Accepted : 2011.03.29
  • Published : 2011.06.20

Abstract

In the present experiments, vortical structures behind the hydrofoil trailing edge are visualized and analyzed as an elementary study for propeller singing phenomena. Two sorts of hydrofoil are selected for the measurement of shedding vortices. One was KH45 hydrofoil section and the other is KH45 with the truncated trailing edge that is positioned at X/C = 0.9523(C=chord length). Assuming the Strouhal number of 0.23, the shedding frequencies of vortices are extracted by analyzing the boundary layer thickness and the flow speed. The frequency distribution of shedding vortices is obtained with the variation of angle-of-attack while the flow speed is fixed to 8m/s. The truncation of the trailing edge makes the frequency of shedding vortices about 120Hz lower than that of original trailing edge and makes the vorticity value higher than the original trailing edge.

Keywords

References

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