Journal of the Korean Society of Marine Environment & Safety (해양환경안전학회지)

The Korean Society of Marine Environment and safety (해양환경안전학회)
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An Experimental Study on the Flow Characteristics around Wedge Type Structure by Slamming

슬래밍에 의한 쐐기형 구조물 주위의 유동특성에 관한 실험적 연구

  • Oh, Seung-Jin (Graduate school, Faculty of Marine Engineering, Mokpo National Maritime Uni.) ;
  • Cho, Dae-Hwan (Faculty of Marine Engineering, Mokpo National Maritime Uni.)
  • 오승진 (목포해양대학교 대학원) ;
  • 조대환 (목포해양대학교 기관시스템공학부)
  • Received : 2013.03.04
  • Accepted : 2013.04.25
  • Published : 2013.04.30
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Abstract

This paper presents are experimental investigation to figure out slamming impact pressure and flow characteristics of a wedge type structure in free fall. The flow field has been obtained by 2-frame grey level cross correlation PIV(Particle Image Velocimetry) method, the impact presure of free fall structure by a pressure acquisition system apply to Dewetron system. The angles between a model and the free surface are adapted $15^{\circ}$, $25^{\circ}$, $35^{\circ}$ and $45^{\circ}$ respectively. Velocity field of water exit has higher better than water entry. The impact pressure under the bottom of the model ha been appeared higher values at 15 degrees than 45 degrees, and also at P1.

본 연구에서는 자유낙하 하는 쐐기형 구조물의 슬래밍 충격압력 및 유동특성을 알아보고자 실험을 수행하였다. 유동장의 계측은 2-프레임 그레이레벨 상호상관 PIV 기법을 이용하였으며, 자유낙하 하는 구조물의 충격압력은 압력 계측장비인 Dewetron System을 이용하였다. 모델과 자유수면간 이루는 각도는 $15^{\circ}$, $25^{\circ}$, $35^{\circ}$ 및 $45^{\circ}$를 적용하였으며 중량과 자유낙하의 높이에 대해서 다양성을 주어 실험하였다. 속도장은 접수보다 이수에서 빠른 유동특성을 나타냈으며, 접수에서 보다 이수에서 시간이 더 소요됨을 보였으며, 모델 하부에서의 충격압력은 모델의 45도에서 보다, 입수각이 작은 15도와 P1 지점에서 높게 나타났다.

Keywords

References

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