• Journal of Advanced Marine Engineering and Technology
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• v.30 no.7
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• pp.771-781
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• 2006

Car acceleration or deceleration induce the surface slope of liquid fuel in the LNG tank. Slope changes the surface area wetted by liquid fuel in the tank and consequently heat leak to the tank. The Fortran program, 'Pro-Heatleak', is developed to evaluate heat leak on LNG tank. The verification test proves the high accuracy of the developed program. The difference between MathCad and computational results is less than 0.07 %. Computational analyses of heat leak are carried out for 10 gallons and 20 gallons of fuel vapor in the tank. With the increasing of fuel vapor volume by 10 percent the wetted surface area and heat leak respectively decrease by 13 percent. The difference between maximum and minimum heat leak is about 10 percent for both 10 gallons and 20 gallons of fuel vapor in the tank.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.9
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• pp.918-922
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• 2015

As international environmental regulations for pollutant and greenhouse gas emissions discharged from ships are being reinforced, it is drawing attention to use LNG as ship fuel. This paper compares the explosion risk potential in the LNG fuel gas supply systems of two types used in marine LNG fuelled vessels. By selecting 8500 TEU class container ships as target, LNG storage tank was designed and pressure conditions were assumed for the use of each fuel supply type. The leak hole sizes were divided into three categories, and the leak frequencies for each category were estimated. The sizes of the representative leak holes and release rates were estimated. The release rate and the leak frequency showed an inverse relationship. The pump type fuel gas supply system showed high leak frequency, and the pressure type fuel gas supply system showed high release rate. Computational fluid dynamics simulation was applied to perform a comparative analysis of the explosion risk potential of each fuel supply system.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.3
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• pp.268-277
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• 2016

This paper aims at presenting bunkering educational programs for LNG fueled ship taking into consideration existing similar education programs and safety systems at the international level in order to enhance both seafarers' and vessels' safety. Heavy fuel oil has typically been used as fuel of ship propulsion. The competitiveness of the fuel oil is recently getting weak in terms of cost and environmental aspects. Liquefied natural gas is introduced for ship propulsion in the maritime field as a new energy source replacing heavy fuel oil. In order to prepare for installation and operation of LNG fueled propulsion ship on board, International Maritime Organization has discussed this subject for about 10 years. As a result of the discussion on such ships in IMO, the International Code of Safety for Ships Using Gases or Other Low-Flash-Point Fuels entered into force on the year 2015. International organizations and several countries therefore drives actively entire researches and other businesses with a view to providing equipment and system of LNG bunkering. The systems are divided into ship-to-ship transfer, terminal / pipeline-to-ship transfer and truck-to-ship transfer. By adopting transfer system of LNG bunkering, many human resources will be needed in these areas on scene as well as on managing, operating, trading, finance, design of LNG bunkering industries. LNG bunkering is just in the beginning stage. Hence, this paper reviews and proposes professional educational programs of LNG bunkering in consideration of technical aspects of the safety system of LNG bunkering based on the types of bunkering systems.

• Journal of the Society of Naval Architects of Korea
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• v.49 no.6
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• pp.504-511
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• 2012

The objective of this study is to investigate tank container to be used as fuel tank for LNG fueled ship. Feasibility of tank container to the fuel tank of LNG fueled ship is addressed and the advantage of tank container as fuel tank of ship is investigated. Conceptual configuration of the tank container is designed as well as structural analyses based on finite element method are carried out to meet the design regulation suggested by shipping register. Static loading is considered by structural analysis and impact test is performed. It is necessary to require SRS(shock response spectrum) in order to investigate structural safety which can meet.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.6
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• pp.451-458
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• 2014

The purpose of this study is to compare the economics between a diesel propulsion vessel and a LNG fuel propulsion vessel through the analysis of the present value using the LCC(Life Cycle Cost) method. This study is also to judge the economics for long-term operation of a LNG fuel propulsion vessel as a result of analysis about the equivalent uniform annual cost. In particular, LCC method was strengthened by sensitivity analysis based on combined interest rate which is considering discount rate and inflation rate simultaneously.

• Journal of the Korean Society of Combustion
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• v.14 no.4
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• pp.25-32
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• 2009

In commercial combustion systems, heavy oil is one of main hydrocarbon fuel because of its economical efficiency. Regarding heavy oil combustion, due to increasing concerns over environmental pollutants such as carbon monoxide, unburned hydrocarbon and nitrogen oxides, development of low pollutant emission methods has become an imminent issue for practical application to numerous combustion devices. Also a great amount of effort has been tried to developed effective methods for practical using of biomass. It is also an important issue to reduce carbon tax. In this paper, an experimental study has been conducted to evaluate the effect of biomass reburning on NOx formation in a heavy oil flamed combustion furnace. Experiments were performed in flames stabilized by a multi-staged burner, which was mounted at the front of the furnace. Experimental tests were conducted using air-carried rice husk powder and LNG as the reburn fuel and heavy oil as the main fuel. The paper reports data on flue gas emissions and temperature distribution in the furnace for several kinds of experimental conditions. NOx concentration in the exhaust has decreased considerably due to effect of reburning. The maximum NOx reduction rate was 62% when the rice husk was used by reburn fuel, however it was 59% when the LNG was used by reburn fuel. The result shows the positive possibility of biomass reburning system for optimal NOx reduction.

• Journal of the Korea Safety Management & Science
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• v.9 no.4
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• pp.149-154
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• 2007

The LNG carriers have been propelled by steam turbines and the LNG boil-off(BOG) has been used as fuel or vented. However, as the alternative propulsion systems such as diesel engines are being equipped on the LNG carriers for better fuel efficiency, a need for the LNG BOG re-liquefaction system that liquefies the BOG and sends the liquid BOG back to the LNG cargo has arisen in recent years. This study investigates the design of the BOG re-liquefaction system based on the reverse Brayton refrigeration cycle. The thermodynamic and heat exchanger analysis are carried out and the limitations to the system performance are discussed.

• Special Issue of the Society of Naval Architects of Korea
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• 2013.12a
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• pp.90-93
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• 2013

RAM study has been used for various range of industry such as chemical, electronics, defense industry. Recently, in the offshore & shipbuilding industry, demand of owners to analysis risk has been increased. RAM study is a quantitative pointer to risk based design and provides effective method for improvements. This article shows the result of RAM study for LNG fuel supply system. The result provides information to improve design. This study shows how result of risk assessment affects the design of LNG fuel supply system.

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.73-74
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• 2018

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.3
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• pp.59-65
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• 1999

To reduce the particulate matter and nitrogen oxides from diesel engine, many studies are proceeding and being accomplished practically. In this situation, LNG engine has important meaning as a clean fuel and alternative energy. In this reason, we try to understand the property of LNG fuel and predict the performance with using LNG engine simulation program and practical test. It could help to lead and apply practically LNG engine was studied in performance and other parameter related with engine performance and compared with current diesel engine. The simulation program was proved to be good in describing the experimental result. This means current heavy duty vehicle could be modified to LNG engine.