A Study on Flow and Creation and Dissipation of Vorticity around Rectangular Floating Breakwater

부방파제의 유동과 와의 생성 및 소멸에 관한 연구

  • Yoon, Jung-Sung (Department of Civil Engineering, Inje University) ;
  • Kim, Myoung-Kyu (Department of Civil Engineering, Inje University) ;
  • Jung, Kwang-Hyo (Department of Naval Architecture and Ocean Engineering, Dongeui University) ;
  • Kim, Ga-Ya (Department of Urban Engineering, Dongeui University)
  • 윤종성 (인제대학교 토목공학과) ;
  • 김명규 (인제대학교 토목공학과) ;
  • 정광효 (동의대학교 조선해양공학과) ;
  • 김가야 (동의대학교 도시공학과)
  • Published : 2008.06.30

Abstract

In this study, flow and creation and dissipation of vorticity around rectangular floating breakwater is investigated both experimentally and numerically. The PIV system(Particle image velocimetry) is employed to obtain the velocity field in the vorticity of rectangular structure. The numerical model, combined with ${\kappa}-{\varepsilon}$ turbulence model and the VOF method based on RANS equation, is used to analyze the turbulence structure. In the results of this study, the vorticity is found around conner of rectangular structure at all time domain, and creation and dissipation of vorticity are closely related to wave period. Separation points of phase of vortex due to flow separation for longer period waves are faster then for shorter period waves.

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