• 한국해양공학회지
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• 제25권5호
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• pp.21-26
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• 2011

Seawater lift pump systems are responsible for maintaining open canal levels to provide the suction flow of circulating water pumps at the set point. The objective of this paper is to design a 2-stage mixed flow pump (for seawater lifting), investigate the new impeller modeling method, and performance improvements of the impeller by using a commercial CFD code. The rotating speed of the impeller is 1,750 rpm with a flow rate of 2,700 m3/h. A finite volume method with a structured mesh and realized k-${\varepsilon}$ turbulent model is used to guarantee a more accurate prediction of turbulent flow in the pump impeller. The performance variables such as the static head, brake horsepower, and efficiency of the mixed flow pump are compared based on changes in the impeller blade shape.

• 한국해양공학회지
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• 제30권1호
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• pp.44-50
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• 2016

An experimental study was performed to investigate the behavior of green water on a structure with a rectangular cross section under wave conditions, along with the flow characteristics in bubbly water flow. An experiment was conducted in a two-dimensional wave flume using an acrylic model (1/125) of FPSO BW Pioneer operating in the Gulf of Mexico under its design wave condition. The occurrence of green water, including its development, in front of the model was captured using a high-speed Charge Coupled Device (CCD) camera with the shadowgraph technique. Using consecutive images, the generation procedure for green water on the model was divided into five phases: flip through, air entrapment, wave run-up, wave overturning, and water shipping. In addition, the distinct water elevations of the green water were defined as the height of flip through, height of splashing jet, and height of freeboard exceedance, and showed a linear relationship with the incoming wave height.

• 대한조선학회논문집
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• 제49권1호
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• pp.79-86
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• 2012

It is very important to investigate and understand the motion of a FPSO on waves because green water phenomenon occurs owing to the relative motions between incident waves and a ship on them. In this research, both experimental and some numerical approaches have been performed in head sea conditions with regular waves. As an object model of this research, a FPSO model is set free to heave and pitch during the experiments. Also, the motions of the FPSO model which are the results of the experiments are used for the corresponding numerical computations. The purpose of this study is to clarify the effect of bow flare on green water load. In this research, it is found that the amount of green water entered from the side of bow is decreased by the increase of bow flare angle. Moreover, the relation between the green water on the bow upper deck and the impact load on the vertical wall located at turrethead is investigated. The results of this research could be used as one of the fundamental data to design bow flares. Also, an optimized bow flare angle is proposed in this study.

• 한국항해항만학회지
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• 제38권1호
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• pp.81-87
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• 2014

국제 유가의 상승과 해양에너지 개발에 필요한 기술이 진보됨에 따라 시추선(drillship), 부유식 원유생산저장설비(FPSO) 등과 같은 해양플랜트의 수요가 꾸준히 증가하고 있는 추세이다. 더불어 이러한 해양에너지 개발사업이 원활하게 이행될 수 있도록 작업을 지원해주는 다양한 종류의 해양플랜트 지원선박과 관련된 건조, 매매, 용선 시장 역시 꾸준한 성장세를 유지하고 있다. 하지만, 국내의 경우 해양플랜트 지원선박과 관련된 정기용선계약 체결 건수가 전무하기 때문에 향후 이와 관련된 선박의 매매 또는 용선계약 시 발생할 수 있는 다양한 법적 분쟁과 준거법 적용에 대한 실무적인 연구가 적극적으로 진행될 필요가 있다. 따라서 이 논문은 "SUPPLYTIME 2005"라고 통칭되고 있는 해양플랜트 지원선박용 정기용선계약서식을 중심으로 기존의 정기용선계약과 다른 특징을 개요적으로 검토함과 동시에 당사자 간에 발생할 수 있는 법적 분쟁에 대한 준거법 지정과 중재의 적용에 대한 실무적인 내용과 절차에 대해 살펴보고자 한다.