• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.186-186
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• 2017

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.166-171
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• 2008

LNG carrier is a special-purpose vessel to transport natural gas (NG) from the place of origin to each consuming country. To increase the capacity of canying LNG carrier, the natural gas is conveyed as a state of liquid called LNG (Liquefied Natural Gas) during a voyage because the total volume of NG is surprisingly reduced when it is cooled down to $-162^{\circ}C$. That is why the design of insulation of the carriers is important to protect LNG from the external heat invasion, and it has been a great challenging subject for several decades in the shipbuilding industry. For this ultimate goal, the boil-off rate (BOR) needs to be accurately estimated during a voyage. Therefore, the goal of this study is to propose a numerical method for estimating the BOR of LNG for given insulation containment subject to external temperature conditions during voyage.

• Journal of Power System Engineering
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• v.9 no.2
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• pp.45-49
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• 2005

Liquefied natural gas takes up six hundredths of the volume of natural gas, which makes storage and transportation much easier. To send out natural gas via a pipeline network across the nation, high-pressure LNG pumps supply highly compressed LNG to high-pressure vaporization facilities. The Number of high-pressure LNG pumps determined the send-out amount in LNG receiving terminal. So it is main equipment at LNG production process and should be maintained on best conditions. In this paper, to find out the cause of high beat vibration at cryogenic pumps, vibration and motor current signal analysis have been performed. High vibration of cryogenic pumps could be reduced due to the modification of motor rotor.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.776-779
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• 2005

Liquefied Natural Gas takes up six hundredths of the volume of natural gas, which makes storage and transportation much easier. To send out natural gas via a pipeline network across the nation, high pressure LNG pumps supply highly compressed LNG to high-pressure vaporization facilities. The Number of high Pressure LNG pumps determined the send out amount in LNG receiving terminal. So it is main equipment at LNG production process and should be maintained on best conditions. In this paper, to find out the cause of high beat vibration at cryogenic pumps, vibration and motor current analysis have been performed. And high beat vibration of cryogenic pumps could be reduced due to the modification of motor rotor.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.6
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• pp.732-741
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• 2020

Environmental regulations have recently been strengthened. Consequently, floating LNG(Liquefied Natural Gas) power plants are being developed, which are new power generation plants that generate electricity by utilizing LNG. A floating LNG power plant generates BOG(Boil-Off Gas) during its operation, and the system design of such a plant should be capable of removing or re-liquefying BOG. However, the design of an offshore plant differs according to the marine requirements. Hence, a process simulation model of the BOG re-liquefaction system is needed, which can be continuously modified to avoid designing the floating LNG power plant through trial and error. In this paper, to develop a model appropriate for the floating LNG power plant, a commercial process simulation program was employed. Depending on the presence of refrigerants, various BOG re-liquefaction systems were modeled for comparing and analyzing the re-liquefaction rates and liquid points of BOG. Consequently, the BOG re-liquefaction system model incorporating nitrogen refrigerants is proposed as the re-liquefaction system model for the floating LNG power plant.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.38-43
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• 2005

The present study is concerned with the numerical analysis of the sloshing impact pressure of the Liquefied Natural Gas (LNG) carriers in rough sea. The reliable predictions of the both random tank motions in irregular waves and violent fluid flow in the LNG tanks are required for practical sloshing analysis procedure of LNG carriers. The three-dimensional numerical model adopting SOLA-VOF scheme is used to predict violent free surface movements of LNG tank in irregular motions. For accurate input motion of tank, a three-dimensional panel method program called SSMP (Samsung Ship Motion Program) is applied for seakeeping analysis. Comparison studies of sloshing analysis are carried out for No.2 tank of 138K and 205K LNG carriers to verify the safety of the LNG containment system of the proposed 205K large LNG carrier.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.11a
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• pp.185-191
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• 2000

1950년 우리나라에 천연가스(LNG : Liquefied Natural Gas)가 공급된 이래로 LNG 소비는 1986년 544천 톤에서 1998년 10644.5천 톤으로 급속히 증가하여 동기간 연평균 55.2%의 증가율을 나타냈다. 더욱이 급격한 수요증가와 함께 난방용 수요 위주의 동고하저형 LNG 소비패턴으로 인하여 공급시설의 효율적 운영과 공급의 안정성에 어려움이 발생되고 있다.(중략)

• Journal of Advanced Marine Engineering and Technology
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• v.18 no.4
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• pp.13-24
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• 1994

The demand of clean energy, like liquefied gas(LNG), increase suddenly because it generates few polluting substances when burned and from the point of view with caloric value it generates ralatively less $CO_2$ gas than the other energy sources. LNG transpotion method of our country is marine transportion by ships because the LNG producing district is far away from Korea. Main engines for most LNG ships are steam turbines, and the efficiency of steam turbine is influenced by the degree of vacuum of main steam condenser. This paper introduce the design method of the vacuum system for high efficiency marine steam turbine. Especially, it is developed the CAD program for the large steam condenser and steam ejector. Also, it is designed the pilot plant including high pressure boiler for the performance test and maked a part of this plant.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.7
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• pp.442-447
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• 2010

FPSO (Floating Production Strorage and Offloading) method for LNG industry is efficient and facile compared to onshore NG (Natural Gas) treatment facility. Five simple natural gas liquefaction cycles for FPSO are presented and simulated in this paper. SMR (Single Mixed Refrigerant) cycle, SNE (Single Nitrogen Expander) cycle, DNE (Double Nitrogen Expander) cycle, PNE (Precooled Nitrogen Expander) cycle, and PDNE (Precooled Double Nitrogen Expander) cycle are compared. Simple analysis results in this paper show that precooling process and adding an expander in the liquefaction cycle is an effective way to increase liquefaction efficiency.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.6
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• pp.756-761
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• 2012

Natural gas is converted in to LNG by chilling and liquefying the gas to the temperature of $-162^{\circ}C$, when liquefied, the volume of natural gas is reduced to 1/600 of its standard volume. This gives LNG the advantage in transportation. In this study, the effects of the pressure drop of refrigerant and natural gas in the LNG heat exchanger of cryogenic cascade refrigeration cycle were investigated and then the design criteria for the pressure drop of refrigerant and natural gas of the LNG heat exchanger were proposed. The pressure drop of the cascade liquefaction cycle was investigated and simulated using HYSYS software. The simulation results showed that the pressure drop in the LNG heat exchanger is set to 50 kPa considering the increase in the compressor work and COP of cryogenic cascade liquefaction cycle.