• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.12
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• pp.775-780
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• 2008

A dynamic model to simulate LNG reliquefaction process has been developed. The model was applied to two candidate cycles for LNG reliquefaction process, which are Reverse Brayton and Claude cycles. The simulation was intended to simulate the pilot plant under construction for operation of the two cycles and evaluate their feasibility. According to the simulation results, both satisfy control requirements for safe operation of brazed aluminum plate-fin type heat exchangers. In view of energy consumption, the Reverse Brayton cycle is more efficient than the Claude cycle. The latter has an expansion valve in addition to the common facilities sharing with the Reverse Brayton cycle. The expansion valve is a main cause to the efficiency loss. It generates a significant amount of entropy associated with its throttling and increases circulation flow rates of the refrigerant and power consumption caused by its leaking resulting in lowered pressure ratio. It is concluded that the Reverse Brayton cycle is more efficient and simpler in control and construction than the Claude cycle.

• International Journal of Air-Conditioning and Refrigeration
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• v.17 no.4
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• pp.135-140
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• 2009

A dynamic model to simulate LNG reliquefaction process has been developed. The model was applied to two candidate cycles for LNG reliquefaction process, which are Reverse Brayton and Claude cycles. The simulation was intended to simulate the pilot plant under construction for operation of the two cycles and evaluate their feasibility. According to the simulation results, both satisfy control requirements for safe operation of brazed aluminum plate-fin type heat exchangers. In view of energy consumption, the Reverse Brayton cycle is more efficient than the Claude cycle. The latter has an expansion valve in addition to the common facilities sharing with the Reverse Brayton cycle. The expansion valve is a main cause to the efficiency loss. It generates a significant amount of entropy associated with its throttling and increases circulation flow rates of the refrigerant and power consumption caused by its leaking resulting in lowered pressure ratio. It is concluded that the Reverse Brayton cycle is more efficient and simpler in control and construction than the Claude cycle.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.93-95
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• 2006

최근 LNG 선박의 발주량이 급증함에 따라 LNG 선에 승무할 인력의 심각한 부족이 예상되고 있다. 이러한 LNG 선박에 승무할 인력 특히 고급 사관의 부족은 선박 자체의 안전뿐 아니라 궁극적으로는 LNG 수송체계의 안전에도 큰 영향을 미치게 될 것이다. 이 발표에서는 현재 전세계 상선대의 현황에서 출발하여, 최근 LNG 선박의 발주 현황, LNG 선박에 적용되는 최신 기술 및 엔진 등에 대하여 살펴 본 후에 전세계 LNG 선박 수주 잔량을 근거로 하여 필요 인력을 예측해 본다.

• Bulletin of the Society of Naval Architects of Korea
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• v.21 no.4
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• pp.1-9
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• 1984

This study is concerned with the economic aspects of $125,000m^3$ class LNG carriers with different propulsion plant such as conventional steam turbine and slow speed diesel engine with reliquefaction plant. The ship's speed and L/B ratio were optimized with criterion of required freight rate(RFR) by using the PROCAL computer program package. In order to investigate the effect of fuel oil price, round trip distance and boil-off rate on the RFR and the optimum speed, sensitivity analysis were also performed.