• Journal of the Korean Institute of Navigation
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• v.21 no.3
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• pp.83-90
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• 1997

Damage stability is generally very important as a part of rescue technique of damaged ship and also in connection with the requirements of MARPOL73/78[2]. Damage stability calculation program has been developed and suggest, which can be used on an onboard computer for any operating drafts. The program is based on lost buoyancy method for calculation of final drafts, and also based on added mass method for calculation of residual righting arm. The numerical method suggested by Hamamoto-Kim[6] is adopted for calculation of intact righting arm(GZ). The model experiments on damage stability are also carried out in a small tank with tanker model 2.385 meters long. The experimental results are compared with the calculations by the suggested method.

• Journal of the Korean Institute of Navigation
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• v.19 no.2
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• pp.13-22
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• 1995

This paper presents the numerical analysis results of the viscous flow for a full ship model. The mass and momentum conservation equations are used for governing equations, and the flow field is discretized by the Finite-Volume Method for the numerical calculation. An algebraic grid and elliptic grid generation techniques are adopted for generation of the body-fitted coordinates system, which is suitable to ship's hull forms. Time-marching procedure is used to solve the three-dimensional unsteady problem, where the convection terms are approximated by the QUICK scheme and the 2nd-order central differencing scheme is used for other spatial derivatives. A Sub-Grid Scale turbulence model is used to approximate the turbulence, and the wall function is used at the body surface. Pressure and velocity fields are calculated by the simultaneous iteration method. Numerical calculations were accomplished for the Crude Oil Tanker(DWT 95,000tons, Cb=0.805) model. Calculation results are compared to the experimental results and show good agreements.

• Journal of Navigation and Port Research
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• v.34 no.9
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• pp.687-692
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• 2010

This study is to improve the marine traffic environment along the west coast of the Korean peninsular so as to prevent the traffic accidents of the dangerous cargo carriers. The most used routes of the vessels were investigated from GICOMS database and the questionnaire survey. Gwanjanghang Sudo strait and Maenggol Sudo strait were considered to have some potential risks to the vessels. In this study, the alternative routes were developed to substitute the current routes near Gwanjanghang Sudo strait and the new boundary line of The Traffic Prohibited Area for Tanker was suggested to contain the Maenggol Sudo strait.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.3
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• pp.54-62
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• 2003

This paper surveys a number of remotely operated recovery techniques and their recent applications in the removal of the toxic liquid from sunken ships, and suggests the appropriate recovery technique for our ocean environment, especially, in view of its cost and efficiency. Authors also give the technical requirements for the suggested remotely operated recovery system and the basic design result which is well-matched with such requirements.

• Journal of Ship and Ocean Technology
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• v.4 no.3
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• pp.21-32
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• 2000

In the present paper, the sloshing flow in the liquid holds of a large tanker is simulated using a numerical method. In the fluid domain, the three-dimensional Navier-Stokes equation with free surface is solved using a finite difference method, and the realistic shapes of multi holds are modeled including the internal members. The time-history of the tank motion is obtained using a time-domain program for ship motion. In order to computer the impulsive pressures on internal structures, a concept of buffer zone is adopted near the tank ceiling during impact occurrence. This study demonstrates that the global fluid motion in the multi liquid holds of ships and FPSO's can be simulated using the numerical method and the corresponding local pressure can be predicted with reasonable accuracy.

• 방재와보험
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• s.36
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• pp.31-33
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• 1988

1960년대까지는 저팽창단백포가 유류화재의 진압에 주로 사용되었으니 불소화합물 계면활성제로부터 유출된 합성 AFFF를 개발하면서 해수로도 이의 사용이 가능하고 지역 및 유출화재 예방에서 AFFF 특유의 초기진압효과 및 대형화재를 방지한다는 장점 때문에 널리 사용되고 있으며, 석유화학산업의 저장탱크지역 및 공정지역에서 AFFF와 FPF가 주로 사용되며 부두시설(Oilrig, Marine Tanker, 해상 / 해변터미널)에는 AFFF의 사용이 지배적이다. 현재 사용되고 있는 foam으로는 단백포(Protein: PF), 불화단백포(Fluoroprotein: FPF), 막형성 불화단백포(Film Forming Fluoroprotein Foam: FFFP), 고팽창폼(High Expansion Foam), 수성막 형성폼(Aqueous Film Foaming Foam: AFFF), 알콜폼(Alcohol Resistant Foam: ATD) 등이 있으니 본고에서는 AFFF 중심으로 소개한다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.3 no.1
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• pp.1-14
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• 1997

This paper describes a series of numerical simulations of colision between a 310, 000 DWT double hull VLCC (struck ship) and three 35, 000, 70, 000 and 105, 000 DWT tankers (striking ships) using LS/DYNA3D. Collisions are assumed to occur at the middle of the VLCC with the striking ships moving at right angle to the VLCC centerline. Striking ship speeds are varied to find a critical speed without failure of inner side shell, and the informations of collision force and absorption energy of each case are also reported. The validation of LS/DYNA3D in this study was made by comparing the result of numerical simulation of LS/DYNA3D with that of double hull tanker grounding experiment by the Carderock Division of Navla Surface Warfare Center (CDNSWC).

• Journal of Ship and Ocean Technology
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• v.5 no.4
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• pp.19-28
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• 2001

A comparative study of the new flexible double hull structure is presented as a collision energy absorbing system, which is constructed with mixed stringers comprising slant and straight stringers for the double hull tanker, The dimension and disposition of this mixed stringers are selected to give the maximum absorbing energy. From the viewpoint of collision energy absorbing efficiency, this structural system is compared with three other types of the double hull constructions with trapezoidal stiffener, stringer type and standard type of VLCC, 310K DWT, Based on the constant hull weight, the proposed double hull structure with mixed stringers shows a improved crashworthiness as the results.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.2
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• pp.662-670
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• 2019

Tanker cargo tanks are equipped with the means of raising and maintaining the cargo discharge temperature to a suitable level. In this paper, a new heating coil design is proposed and analyzed. Contrary to conventional designs, wherein the heating coils are evenly distributed over the tank bottom, the proposed design arranges the heating coils in the central part of the tank bottom, in a vertical direction. Due to the intensive cargo circulation generated, a forced convection is superimposed on a buoyancy-driven natural convection, providing a more efficient mixed convection heat transfer mechanism. Numerical simulations performed by using a finite volume method show that in the case of 7-bar steam Bunker C heavy fuel oil heating, a five-hour circulation phase average heat transfer coefficient equals 199.2 W/m²K. This result might be taken as an impetus for the more thorough experimental examination.

• Journal of the Korean Society for Marine Environment & Energy
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• v.2 no.2
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• pp.86-94
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• 1999

This paper describes a development of Collision/grounding Strength Assessment System (COSAS) using simplified method. This method is formulated in closed-form equation by taking into account crushing caused by bulbous bow collision and cutting caused by forward speed grounding. To verify the accuracy of the developed system, some examples for test models of double side/bottom structure in collision/grounding situation are considered. This system might be useful for analysis of structural damage of oil tankers in collision/grounding.