• Journal of the Society of Naval Architects of Korea
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• v.35 no.3
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• pp.38-45
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• 1998

In this parer, the effects of a skeg, rudder and stern hull form on the manoeuvrability of a container carrier with small length to draft ratio have been investigated through a series of model test. Rudder open water tests and PMM tests were carried out with varying rudder area, afterbody appendages and stern hull form to investigate their effects on the manoeuvrability. The MMG model developed in Japan was used for the manoeuvring simulation with experimentally obtained hydrodynamic coefficients. The result showed that the effects by the variation of stern profile and the skeg below stern bulb are much larger than those by any other types of appendages in improving directional stability of the vessel.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.3
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• pp.1-13
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• 2001

RANS solver has been developed to solve the flows past a ship with a drift angle. The solver employs a finite volume method for the spatial discretization and Euler implicit method for the time integration. Turbulent flows are simulated by Spalart-Allmaras one-equation model. Developed solver is applied to analyze the hydrodynamic forces and flows of two tankers with a same forebody but different afterbodies. The computed flows and hydrodynamic forces are compared with the measured flows and captive model test data. The computed results show good agreements with experimental data and show clearly the effects of stern hull form on the hydrodynamic forces and the flows.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1995.10b
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• pp.118-124
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• 1995

본 연구에서는 유전자 알고리즘과 Hooke & jeeves 방법을 적용한 퍼지모델링 기법 을 이용하여 저속비대선에서 선미형상의 주요치수를 결정하고, 이를 실적선과 비교하였다.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.560-565
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• 2016

최근 대형 컨테이너선의 개발이 지속적으로 이루어짐에 따라 슬래밍에 의한 선수 및 선미의 구조안정성 문제가 대두되고 있지만 설계 단계에서 슬래밍에 대해 고려하기에는 현상의 복잡성으로 인해 어려움이 많았다. 이를 위해 KRISO에서 시행된 WILS JIP의 선수 단면 형상 및 선미 단면인 쐐기 형상으로 격자를 생성하여 EDISON CFD 다상유동 해석자를 통해 수치해석을 시도하였다. 기존 방식과 달리 계산 시간 절감을 위하여 격자 변형 기법을 적용하지 않고 모형 시험결과를 기반으로 한 유입류 조건을 설정하여 입수 충격 문제를 해석해보았다. 그 결과, 선미 형상의 경우 선행연구와 유사하게 실험 결과에 근접한 유체 충격력을 정량적으로 얻어낼 수 있었다. 선수 형상의 경우에서는 구상 선수로 인해 파생되는 센서 위치별 충격력의 변화를 확인할 수 있었으며, 실제 유동에 가까운 유동 형상과 슬래밍에 의한 충격력을 개략적으로 구할 수 있었다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2010.10a
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• pp.46-47
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• 2010

추진기와 타가 놓여있는 선미부에서의 난류 유동에 의한 저항을 증가시키는 요인이 집중되어 있다. 트랜섬 선미를 가지고 있는 선박의 경우 선미선형에 의한 저항의 형태가 달라진다. $Re=2.8{\times}10^5$의 균일흐름에서, 선저와 트랜섬이 이루는 각도를 각각 $45^{\circ}$, $90^{\circ}$, $135^{\circ}$로 변형하여 선미선형을 선정하였으며, 자유 수면에서 모델의 하부까지의 깊이는 동일하게 적용하였다. 선저가 끝단에서 트랜섬 선미형상에 의해 급격한 각도를 이루는 지점에서 상하로 맥동하는 유동특성이 나타나며, 각도가 증가 할수록 와의 형태가 작아져 난류의 발생이 감소하였다.

• Journal of the Society of Naval Architects of Korea
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• v.33 no.1
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• pp.153-160
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• 1996

This paper presents a method that determines the stem profile dimensions for full, slow-speed ship using fuzzy modeling applied the genetic algorithm and compares with the database of ships.

• Journal of Navigation and Port Research
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• v.35 no.10
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• pp.805-810
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• 2011

An experiment was carried out to figure out the instantaneous flow characteristics in the wake of the transom stern's 2-dimensional section by 2-frame grey level cross correlation PIV method at $Re=3.5{\times}103$, $Re=7.0{\times}103$. The stern angles of models were learning at $45^{\circ}$(Model "A"), $90^{\circ}$(Model "B") and $135^{\circ}$(Model "C") respectively based on the survey results of real ships. The depth of wetted surface is 40mm from free surface. As Reynolds number increases, vortices increase in volume and move their way to the downstream. Flow separation appeared at the end of model's bottom.

• Journal of Navigation and Port Research
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• v.29 no.8 s.104
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• pp.667-671
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• 2005

This study was carried out to examine the prediction of ship's manoeuvrability in initial design stage. New parameter representing basic hull form and stem shape were proposed. Captive model test were carried out to investigate the correlation coefficient between hydrodynamic coefficient and hull parameter. The results showed which parameter are positive correlation with hydrodynamic coefficient. Moreover correlation was examined between stem hull shape and ship's manoeuvrability. New empirical formulas for hydrodynamic coefficients were proposed These results can be used to predict a ship's manoeuvrability in initial design stage.

• Bulletin of the Society of Naval Architects of Korea
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• v.29 no.3
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• pp.55-56
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• 1992

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.5
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• pp.552-557
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• 2015

A numerical simulation studies were performed to investigate a manoeuvring characteristics as function of stern hull form with the mathematical model. In order to consider the effect of the stern hull form and obtain the manoeuvring characteristics, a parameter($C_{wa}$) which is aft. water plane area coefficient is modified. Because modifying $C_{wa}$(${\pm}2%$) means that the stern hull form is modified to V-type or U-type, the numerical simulation was performed with this modified $C_{wa}$. A changing trend for the manoeuvring characteristics not only in deep water but also in shallow water such as directional stability, turning and zig-zag was investigated and presented as the results. Present study showed that the manoeuvrability in shallow water largely changed when the draught and water depth ratio(=d/H) become 0.5, and the stern hull form can affect to the manoeuvrability of a vessel navigating in restricted water depth. In addition, it showed that approaching the stern hull to U-type makes the advance and tactical diameter of turning motion large and the overshoot angle of zig-zag motions small. Otherwise, it showed approaching the stern hull form to V-type makes the advance and tactical diameter of turning motion small and the overshoot angle of zig-zag motions large in the present study.