Experimental Study on Flow Characteristics of Regular Wave Interacting with Rectangular Floating Structure Using PIV Technique

PIV시스템을 이용한 규칙파중 2차원 사각형 부유식 구조물 주위의 유동특성 연구

  • Jung, Kwang-Hyo (Department of Naval Architecture and Ocean Engineering, Pusan National University) ;
  • Chun, Ho-Hwan (Department of Naval Architecture and Ocean Engineering, Pusan National University)
  • 정광효 (부산대학교 조선해양공학과) ;
  • 전호환 (부산대학교 조선해양공학과)
  • Published : 2006.12.30

Abstract

This experimental study investigated the flow characteristics for regular waves passing a rectangular floating structure in a two-dimensional wave tank. The particle image velocimetry (PIV) was employed to obtain the velocity field in the vicinity of the structure. The phase average was used to extract the mean flow and turbulence property from repeated instantaneous PIV velocity profiles. The mean velocity field represented the vortex generation and evolution on both sides of the structure. The turbulence properties, including the turbulence length scale and the turbulent kinetic energy budget were investigated to characterize the flow interaction between the regular wave and the structure. The results shaw the vortex generated near the structure corners, which are known as the eddy-making damping or viscous damping. However, the vortex induced by the wave is longer than the roll natural period of the structure, which presents the phenomena opposing the roll damping effect; that is, the vortex may increase the roll motion under the wave condition longer than the roll natural period.

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