Journal of the Society of Naval Architects of Korea (대한조선학회논문집)

The Society of Naval Architects of Korea (대한조선학회)
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A Study on the Characteristics of an Air Cavity Attached Under a Flat Plate

평판에 형성된 공기공동 특성에 관한 연구

  • Kim, Jong-Hyun (Flowin Tech Co., Ltd.) ;
  • Oh, Jae-Young (Naval Ship Engineering Center, Naval Force Analysis Test & Evaluation Group) ;
  • Seo, Dae-Won (Department of Naval Architecture and Ocean Engineering, Inha University) ;
  • Lee, Seung-Hee (Department of Naval Architecture and Ocean Engineering, Inha University)
  • 김종현 (플로윈테크(주)) ;
  • 오재용 (해군본부 전력평가단 함정기술처) ;
  • 서대원 (인하대학교 조선해양공학과) ;
  • 이승희 (인하대학교 조선해양공학과)
  • Received : 2010.08.02
  • Accepted : 2011.07.18
  • Published : 2011.10.20
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Abstract

The concept of an air lubrication has long been an object of attention since it can be utilized to reduce the frictional resistance, and what is more, it is eco-friendly. The present study examines the basic characteristics of an air cavity with intention of applying the air lubrication technology to the reduction of the resistance of a ship without excessive power increment. For the purpose, an air cavity was created at the bottom of a flat plate by injecting air behind a backward step and the hydrodynamic properties of the air cavity and the surrounding flow has been investigated experimentally and numerically. The influence of the step height and the air flow rate have been more carefully studied since they are presumed to be the main parameters affecting the characteristics of an air cavity. The results indicates that the shapes of the air cavities attached on the flat plate become "U" or "V" type depending on the incoming flow velocity and air flow rate. The study also confirms that the length of the air cavity increases with increase in air flow rate but there is a certain critical limit in the flow rate above which increase in the air cavity length is no more evident.

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References

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  1. Visualization of Microbubbles Affecting Drag Reduction in Turbulent Boundary Layer vol.52, pp.4, 2015, https://doi.org/10.3744/SNAK.2015.52.4.356