• Journal of Ocean Engineering and Technology
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• v.31 no.2
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• pp.91-102
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• 2017

Recently, a new type of LNG membrane Tank called the "KC-1 membrane LNG Tank" was developed by KOGAS (Korean Gas Corporation). It is necessary to estimate the temperature distribution of the hull structure and insulation system for this new LNG tank, as well as the BOR (Boil-Off Rate) when exposed to outside temperature conditions to ensure the integrity of the tank structure and limit LNG evaporation, from a safety evaluation point of view. In this study, temperature distribution calculations for the hull structure and insulation system of the KC1 membrane tank were compared by employing four numerical approaches under the IGC condition. Approaches 1-3 studied 2D simulations and approach 4 used a 3D numerical simulation. Approach 1 was calculated by in-house Excel VBA codes and the three other approaches utilized ANSYS Fluent. The BOR of approach 4, the 3D simulation case, for the IGC condition was 0.0986%/day.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.10a
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• pp.293-293
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• 1998

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.296-296
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• 2002

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.169-170
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 1999.10a
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• pp.275.1-275
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• 1999

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.05a
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• pp.373-374
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• 2018

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.7
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• pp.749-755
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• 2011

The performance and emission characteristics of a CNG (compressed natural gas) engine were experimentally investigated under different natural gas compositions. The engine specifications were as follows: 6606 cc, turbo, lean-burn-type; its ignition timing was fixed for the fuel gas with a HHV (higher heating value) of 10454 kcal/$Nm^3$. The experimental results showed that when the HHV of the fuel gas was changed from 10454 kcal/$Nm^3$ to 9811 kcal/$Nm^3$ and 9523 kcal/$Nm^3$, the average power reductions were 3.2 % and 3.4 % (1.5 % and 2.1 %, respectively, with A/F control switched off), respectively, and the average thermal-efficiency reductions were 1.1 % and 1.5 % (1.5 % and 2.1%, respectively, with A/F control switched off), respectively. The emissions of $CO_2$, CO, and $NO_x$ decreased as the HHV of the fuel gas was lowered. On the other hand, the emissions of THC (total hydrocarbon) were not consistent, and the extent of change in their emissions was small.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.1
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• pp.54-61
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• 2008

Integrated Gasification Combined Cycle (IGCC) power plant converts coal to syngas, which is mainly composed of hydrogen and carbon monoxide, by the gasification process and produces electric power by the gas and steam turbine combined cycle power plant. The purpose of this study is to investigate the influence of using syngas in a gas turbine, originally designed for natural gas fuel, on its performance. A commercial gas turbine is selected and variations of its performance characteristics due to adopting syngas is analyzed by simulating off-design gas turbine operation. Since the heating value of the syngas is lower, compared to natural gas, IGCC plants require much larger fuel flow rate. This increases the gas flow rate to the turbine and the pressure ratio, leading to far larger power output and higher thermal efficiency. Examination of using two different syngases reveals that the gas turbine performance varies much with the fuel composition.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.3
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• pp.213-220
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• 2007

Appropriate numerical models for the simulation of off-gas flow in hot area of the vitrification plant have been developed in this study. The models have been applied to analyze the effect of design parameters of real plant and numerical analyses have been performed for CCM(Cold Crucible Melter), pipe cooler and HTF(High Temperature Filter). At first, the effect of excess oxygen and the ratio of oxygen distribution on combustion characteristics in the CCM has been studied. Next, solidification behavior of radio nuclide in the pipe cooler has been numerically modeled and scrutinized. Finally, flow pattern in accordance with the location of off-gas entrance of the HTF has been compared.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.11a
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• pp.69-78
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• 2005

Appropriate numerical models for the simulation of off-gas flow in hot area of the vitrification plant have been developed in this study. The models have been applied to analyze the effect of design parameters of real plant and numerical analyses have been performed for CCM(Cold Crucible Melter), pipe cooler and HTF(High Temperature Filter) At first, the effect of excess oxygen and the ratio of oxygen distribution on combustion characteristics in the CCM has been studied. Next, solidification behavior of radio nuclide In the pipe tooler has been numerically modeled and scrutinized. Finally, flow pattern In accordance with the location of off-gas entrance of the HTF has been compared.