• Journal of the Society of Naval Architects of Korea
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• v.46 no.4
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• pp.398-408
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• 2009

Crude oil carriers or product oil carriers are confronted with sea pollution due to hull damage from various accidents. To reduce the oil spillage of tankers, IMO(International Maritime Organization) and OPA 90(Oil Pollution Act 1990) adopted the hull structures of double skin type. In this study, oil spillage test of the double skin tanker with 1/100 scaled model was carried out under damaged condition due to collision and grounding accidents. A new structural type of oil tanker was also tested with pipe and valve system arranged in double side and single bottom hulls. Their results were compared with that of conventional type double hull on the view point of ship safety and oil spillage.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1999.06a
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• pp.87-92
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• 1999

최근 우리나라에서는 가스사용시설의 확대, 석유화학 플랜트의 급격한 성장 및 LNG, 원유 등의 운반에 필요한 특수선의 증가등으로 인하여 사회 일상주변에 각종의 인화성 액체 또는 폭발성가스가 존재하는 기회가 많아 졌으며, 폭발성 위험물질의 취급이 점차 대규모화, 다양화, 복잡화 되어가고 있다. 이러한 현실속에서 폭발사고 방지에 대한 연구와 폭발성가스가 존재하거나 존재할 우려가 있는 위험장소에서 사용되는 방폭형 전기기기의 방폭성능에 대한 확인과 안전성을 평가하는 기술의 확립이 필요하다. (중략)

• Journal of the Society of Naval Architects of Korea
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• v.41 no.5
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• pp.63-69
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• 2004

This study contains the CFD analysis to predict the flow in engine room and utilize the results as a reference for arranging smoke detectors. FLUENT, a commercial CFD code is adopted because of its good application experience in DSME(Daewoo Shipbuilding & Marine Engineering Co.. Ltd.). The target is the engine room of VLCC. which was delivered in 2002. The model for analysis includes main structure elements, ventilation ducts, main engine and other big size equipment. From the analysis results, the internal flow pattern can be observed and some guidelines for the position of smoke detectors cane be presented.

• The Journal of shipping and logistics
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• v.34 no.4
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• pp.615-635
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• 2018

Using data from 2008 to 2017, this study analyzed the financial characteristics of offshore freight shipping companies in Korea, categorized by vessel type, and their impact on business performance. The analysis showed an upward trend in the overall debt ratio of offshore freight transport companies and differences in the financial characteristics of each vessel type as well as the major factors affecting business performance. In particular, the significant factors affecting the ROA performance of the business are the size of business and debt ratio in the LPG line; the growth rate in the bulk line; the size of business, debt ratio, and year in the general freight line; and the size of business, growth rate, entertainment expense rate, debt ratio, and year in the full container line. Therefore, each shipping company needs to recognize differences in key financial factors affecting its performance based on vessel type, implement proactive measures, and diversify its vessel portfolio.

• Journal of the Korean Institute of Gas
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• v.21 no.1
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• pp.65-71
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• 2017

LNG is being spotlighted as a clean marine fuel because of recent trend in reinforcement of marine environmental regulation. In this paper, demand prospect of LNG bunkering for Ulsan port is carried out to analgize the possibility of commercialization of floating LNG bunkering terminal. Environmental analysis for LNG bunkering and LNG bunkering trends of competitive ports in the world are considered to draw out the prospection of LNG bunkering demand in Ulsan. As a result, car carrie and oil carrier were expected to have more possibility in switching to LNG fuelled ship. The LNG bunkering demand in Ulsan. As a result, car carrier and oil carrier were expected to have more possibility in switching to LNG fuelled ship. The LNG bunkering demand in Ulsan port was expected to be about from 650,000 ton to 900,000 ton in 2030 and Ulsan port is prospected to be a good port for FLBT business in th future.

• Journal of Navigation and Port Research
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• v.38 no.1
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• pp.19-27
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• 2014

When a ship operates in a shallow water and channel, the hull sinkage and asymmetrical force generated around the ship by the influence of sea bottom and bank walls are caused collision with sea bottom, other ships or the bank itself. Especially, the shipping company and pilots navigating the area of Europe and North America with many channels are deal with it as a important matter to prevent collision. In this paper, hydrodynamic force generated between the ship and bank using the numerical analysis for the safe navigation of ship, that is, sway force and yaw moment should be presumed qualitatively. It makes a program for fluid analysis of the shallow water and bank effect. Analyses are carried out for three kind of parameter, that is, ship's speed, water depth and ship-bank distance for crude oil carriers. The numerical analysis results are compared with results of the experiments and the previous published papers.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.84-89
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• 2005

The double hull VLCC(Very Large Crude Oil Tanker) have been designed to have each four(4) longitudinal bulkheads and transverse bulkheads in general. Actually, the inside longitudinal bulkheads among four(4) longitudinal bulkheads, which are extended up to the end of the aft cargo hold for continuity of the members, have been designed with knuckled type inboard due to the narrowed hull shape at bottom region, but sometimes the straight type of longitudinal bulkheads were adopted based on the degree of the hull lines shape. However, regardless the type of longitudinal bulkheads, inside and outside longitudinal bulkheads conflict each other in aft cargo hold region This makes the structure more complex thus giving difficulties to structural design and production. Recently, a vessel of straight type was reported to have cracks on bracket end and tripping bracket toe in aft cargo hold region. As a solution to this problem, in designing the first 60m Beam VLCC, DSME developed a new cargo hold structure which is good in production and structural point of view by structural strength and fatigue analysis of fore and aft cargo hold.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.426-426
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• 2006

선박이 천 흘수 및 수로를 운항하는 경우 바닥과 벽면의 영향으로 인해 선체침하 및 비대칭적인 힘이 선체 주위에 발생하여 바닥이나 다른 선박 혹은 수로의 벽에 충돌하는 현상이 발생한다. 특히, 수로가 많은 유럽이나 북미를 운항하는 해운회사와 항해사들은 선박의 충돌을 방지하기 위해서 중요한 문제로 다루고 있다. 따라서, 본 연구에서는 선박의 안전한 항해를 위해 수치해석을 이용하여 선박과 벽면 사이에 발생하는 유체역학적 힘, 즉 Sway force와 Yaw Moment를 정성적으로 추정하고자 하였다. 천 흘수 유동 해석용 프로그램을 작성하였으며, 검증을 위해서 Wigley 선형에 적용하여 h/T별로 계산을 수행하여 시험결과와 비교하였다. 그리고, 벽면효과를 해석 할 수 있는 프로그램을 작성하여 실적선인 원유운반선 2척에 대하여 3가지 파라메터, 즉 선속, 수심 그리고 선박과 벽면 사이 거리의 변화에 따른 다양한 계산을 수행하였다. 계산된 결과는 시험결과 및 기 발표된 수치해석 결과와 비교하였다. 기 발표된 논문에서는 시험결과와 계산결과가 상이한 결론을 보여 주었는데, 그 이유는 수치해석에 있어서 자유표면 문제를 선형화된 자유표면 조건식을 사용한 부분을 가장 큰 이유로 언급하였다. 하지만, 본 연구의 결과는 Sway force와 Yaw Moment가 기 발표된 논문의 시험결과와 정성적으로 일치함을 보여 주었다. 본 연구를 통해 수치해석 방법으로 선박에 작용하는 비대칭 유동에 대한 유체역학적인 힘을 정성적으로 추정할 수 있었고, 제한된 수로에서 선박의 조종성 예측 및 수로 설계시 유용한 정보를 제공할 수 있을 것이라고 판단되어 진다.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.69-75
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• 2005

Recently it was reported that the vibration problems on the oil pipe support structure of the crude oil carrier were occurred. in order to investigate the vibration characteristics and the causes of the vibration occasionally. the vibration measurements and impact tests for the oil Pipe structure were carried out. From the measurement results severe vibration was caused by the resonance between the transversal natural frequency of the structure and $6^{th}$ order excitation force of the main engine. Providing the proper countermeasures a series of the vibration analyses were carried out based on the measurement results. From the analysis results, it was concluded that the vibration characteristics of the oil pipe structure were affected by the oil pipes, support structure itself, upper deck structure and the installation spaces and the standard design was established for the crude oil carriers.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.1
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• pp.15-22
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• 2011

In this paper, cavitation patterns of model tests were compared with those of full-scale measurement for a propeller of crude oil carrier which was suffered from erosions on suction side of blade tip region. Cavitation tests were performed at design and ballast draft using model and full scale nominal wakes. A model ship and wire mesh method was used for the simulation of wake patterns of model nominal wakes. For the prediction of full-scale wake patterns, a RANS solver(Fluent 6.3) was used and wire mesh method was used for the simulation of the full scale wakes. Comparison results show that cavitation patterns using predicted full-scale wake patterns are closer to cavitation patterns of full-scale measurement at ballast draft condition. Also, cloud cavitations were observed on the position of eroded area at both full-scale measurement and cavitation tests using simulated full-scale wake patterns.