• Coupled systems mechanics
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• 제7권2호
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• pp.163-176
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• 2018

The ship hydrodynamics in static and dynamic states were investigated using 3-dimensional numerical simulations. The static case simulated a fixed ship, while the dynamic case considered a ship with free sinkage and trim using the mesh morphing technique. High speed was found to increase the wave elevation around the ship. Compared with the static case, the dynamic case seemed to generate higher waves near the bow and after the stern. The frictional resistance was found be to more dominant. However, the pressure resistance became gradually important with the increase of the ship speed. The trim and sinkage were also analyzed to characterize the ship hydrodynamics in the dynamic state.

• 한국항해항만학회지
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• 제26권1호
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• pp.1-7
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• 2002

전복한 저건현 내항 탱커의 사고 원인을 조사하기 위하여 복원성에 영향을 미치는 자유표면영향과 저건현 선박에서 발생하는 해수침입, 침수침하 현상에 대하여 알아보았다. 피리고 선회시에 발생하는 경사 모멘트륵 계산하고 사고 선박의 경사 모멘트를 추정하였다. 이상의결과로부터 사고 선박의 복원성 상실에 의한 전복 원인을 고찰하였다.

• 수산해양기술연구
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• 제44권1호
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• pp.68-74
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• 2008

This study is concerned with the development of the basic planing hull form of small fishing boat in 25 knots high speed. A series of model test to determine the optimum performance hull form of actual fishing boat with 10 gross tonnage was carried out for 5 models made available planing hull form in the circulation water channel. Model test was performed with the resistance test to study the hydrodynamic characteristics of model ships and the sinkage and trim measurement to investigate the stability of model ships and also the wave pattern observation to analyze the effectiveness of model ships. As the result, the planing hull form of P-4 with deep V type bow can be derived as the best hull form with good performance especially in ship's resistance efficiency showing less residual resistance and sinkage and trim and the spray effect, etc..

• 한국해양공학회지
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• 제17권5호
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• pp.88-94
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• 2003

A series of tests of 5 model ships, selected from a data survey of 10 Gross Tonnage actual fishing boats, were performed in two circulating water channels (Chosun University in Korea and WJFEL in Japan), in order to develop the basic hull form of a 25 knots-class fishing boat. Resistance tests, trim and sinkage measurements and wave pattern observations etc., were included in each I1wdel test, and the model test results were compared and analyzed. The result was as follows: P-4 hull form ship changed into Deep V type bow is the best hull form with good performance, especially with regard to ship's resistance efficiency.

• 한국해양공학회지
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• 제30권2호
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• pp.69-74
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• 2016

A new wave-piercing-type high-speed planing boat without a chine was developed, and its basic performance was investigated in a model test, including the resistance, trim, and sinkage. The maximum speed of the developed ship was 35 knots. The hull form was developed by combining a VSV (very slender vessel) and TH (transonic hull), which have large deadrise angles at the bow. The main dimensions were estimated by a statistical approach using actual ship data. The effect of a side fin attached at the stern near the water line was investigated from a resistance point of view. It was found that the developed hull form showed the possibility of a new concept for a high-speed planing hull without a chine, and the side fin played an important role in increasing the resistance performance by controlling the trim and sinkage in the high-speed range.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2002년도 춘계학술대회논문집
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• pp.145-153
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• 2002

A coastwise chemical tanker sailing at full speed has capsized in calm water and whole turing. In the precious paper, we investigated reasons of the accident by demonstrating the proper correction for the free surface effect of the liquid cargo and the bow-sinkage effect. In this paper, we also carry out model experiments of a transverse pressure under the seawater and an outward heel moment according to the heel angle and rudder angle, on the basis of radius of turning circle, ship's speed and drift angle of model ship occurring in turning. It is also shown that the flooding of seawater onto the deck occurring in turning generated a significant outward heel moment and the vertical distance between the center of gravity of the ship and the renter of lateral water drag.

• 대한조선학회논문집
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• 제34권4호
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• pp.72-83
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• 1997

본 연구에서는 연안 및 운하, 두 곳 모두에서 운항이 가능한 컨테이너선에 대한 선형설계를 수행하였다. 설계된 선형은 기존의 140TEU 컨테이너선을 기준선으로 하여 설계된 200TEU급 컨테이너 선형으로, 선수부에 대하여는 기존의 저항시험 자료들을 통한 선형의 재설계도 시도되었다. 모형시험은 선형시험수조에서 일반적인 저항시험을 통한 전저항, 침하와 트림(trim)이 제측되었으며, 선체주위 유동장의 해석을 위한 수치해석으로는 무한수심 뿐만 아니라 제한수로상태에 대하여도 MAC법을 기초로 한 유한차분법(Finite-Difference Method)에 의해 계산이 수행되었다. 이러한 일련의 모형시험 및 유동장의 수치해석을 통하여 설계된 선형의 저항 특성을 파악하였다.

• 한국항해항만학회지
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• 제27권5호
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• pp.465-471
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• 2003

내항 탱커가 비교적 정온한 해역에서 타선을 피하기 위해 대각도 조타론 행한 결과, 선회 중에 전복하는 사고가 발생하였다. 저자들은 전 논문에서 비중량이 큰 액체화물의 자유표면영향에 의한 중심상승과 전진 항해 중에 발생하는 선체 침하와 이로 인하여 생기는 선체 트림의 변화 때문에 발생하는 복원력 감소를 고려하여 사고선박의 복원력 곡선을 계산하였다. 본 논문에서는 먼저 전복사고를 당한 선박의 모형선을 제작하여 자항 선회실험을 실시하고 전복선박의 정상 선회시의 선회반경, 편류각 및 선속을 계측한다. 그리고 자항 선회실험을 통하여 얻은 선회반경, 선속 및 횡 편류각을 기초로 하여 각 경사각에 따른 측 압력과 경사 모멘트에 관한 실험을 실시하고, 갑판상 해수 침입이 측 압력과 경사 모멘트에 미치는 영향에 대해서 파악한다. 마지막으로 선회시 해수 침입으로 인해 발생하는 외측 경사 모멘트와 측압 중심의 변화론 조사함으로써 전복사고가 발생한 저건현 내항 탱커의 복원성에 대하여 검토를 하였다.