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Hydraulic Model Experimental Study on the Rope Kink Phenomena and Mooring Block Behavior under Wave Conditions at a Seaweed Farm

연승 수하식 양식시설의 파랑 중 해조류 꼬임 현상 및 계류용 블록 이동에 관한 수리모형 실험적 연구

  • Kim, Heon-Tae (Department of Ocean Engineering, Pukyong National University) ;
  • Choi, Jin-Hyu (Department of Ocean Engineering, Pukyong National University) ;
  • Yoon, Han-Sam (Research Center for Ocean Industrial Development, Pukyong National University)
  • 김헌태 (부경대학교 해양공학과) ;
  • 최진휴 (부경대학교 해양공학과) ;
  • 윤한삼 (부경대학교 해양산업개발연구소)
  • Received : 2013.07.25
  • Accepted : 2014.02.25
  • Published : 2014.04.28

Abstract

In this study, a hydraulic model experiment under wave conditions was carried out to investigate the gap/distance between two near-unit farm lines that affects the rope kink and shape variation of a seaweed farm during mooring block movement. As a result, rope kink occurred during the low wave height condition as the gap/distance between the two near-unit farm lines decreased. The seaweed farm maintained a stable shape in the higher wave height conditions as the gap/distance between the two near-unit farm lines increased. This result indicates that rope kink is sensitively affected by the gap/distance between the two near-unit farm lines. A tendency to increase the critical wave height was observed when mooring block movement occurred, and as the mooring block weight and wave period increased. From the experimental results in which incident wave conditions and the mooring block weight changed, as the front side mooring block weight increased from 3.0 to 8.0 tons, the seaweed farm was stable, and rear side mooring block movement hardly occurred. The observed tension of the seaside mooring line was a maximum at about 3.0 ton/m.

본 연구에서는 연승 수하식 양식시설의 파랑 중 해조류의 꼬임 현상에 영향을 미치는 연승줄의 간격, 계류 블록의 이동에 따른 양식장 형상변화 등을 수리모형실험을 통해 검토하고자 하였다. 실험결과로부터 해조류의 꼬임현상은 연승간격이 감소함에 따라 낮은 파고에서도 발생하였으며, 연승줄 간격이 클수록 보다 큰 파랑조건에서도 해조류 꼬임현상이 발생하지 않는 안정한 상태를 유지하였다. 이는 해조류의 꼬임 현상은 연승간격에 민감하게 영향을 받음을 나타낸다. 또한 블록 중량 및 주기가 길어짐에 따라 전체적으로 계류블록이 이동하기 시작한 임계파고가 커지는 경향을 나타내었다. 입사파랑 조건과 계류 블록 중량을 달리한 실험결과로부터 전면 블록 중량이 3.0 ton에서 8.0 ton으로 증가함에 따라 안정성이 크게 확보되는 결과를, 반대로 후면에서는 블록의 거동이 거의 발생하지 않았다. 이때 전면 계류삭의 최대 장력은 약 3.0 ton/m을 나타내었다.

Keywords

References

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