• 에너지공학
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• 제23권4호
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• pp.236-239
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• 2014

한수원 중앙연구원은 2007년부터 정부과제의 하나로 전기출력이 1500MWe급인 GEN.III+ 원전 APR+를 개발하고 있다. APR1400에 비해 보다 개선된 안전성과 경제성을 갖는 원전을 개발하기 위해 국내 건설 중인 원전과 해외에서 개발 또는 건설 중인 ALWR(Advanced Light Water Reactor)의 설계내용 및 후쿠시마 원전사고로부터 도출된 개선사항을 반영하여 한국 실정에도 맞고, 해외 수출형 원전에도 부합되는 원전을 설계하고 있다. APR+의 경쟁력을 확인하기 위해 APR+ 표준설계개발 단계에서 3회의 경제성 평가를 수행하였다. 표준설계개발 단계에의 3차(최종) 경제성 평가 결과 APR+ N-th호기는 국내석탄화력 1000MWe급 대비 약 23% 경쟁력 우위인 것으로 평가되었다.

• 한국재료학회지
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• 제27권10호
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• pp.563-568
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• 2017

In this study, the coating of an Al-Cr layer on the surface of a Zircaloy-4 alloy was carried out through plasma pretreatment coating and a laser surface melting process. Two different conditions for laser treatment, severe or minimal surface melting of the Zr alloy substrate, were applied to form the final coating. When there was significant surface melting of the Zr alloy, the solidification microstructure of the newly formed coating layer was mainly composed of needle-shaped $Al_3Zr$, Al(Cr) and $Al_7Cr$ phases. On the other hand, the solidification microstructure of the coating layer was mainly composed of Al(Cr) and $Al_7Cr$ phases when there was minimal surface melting of Zr base in the laser process. However, when the coating was maintained at $1100^{\circ}C$ for 2 hours, significant inter-diffusion occurred between the phases in the coating. As a result, the upper part of the coating layer was observed to mainly consist of $Al_3Zr$ and $Al_8Cr_5$ phases, regardless of the laser treatment conditions.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2018년도 추계학술논문요약집
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• pp.104-104
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• 2018

Kori Unit 1 is the first permanent shutdown nuclear power plant in Korea and it is on June 18th, 2017. Spent fuel assemblies began to be discharged from the reactor core to the spent fuel pool(SFP) within one week after shutdown of Kori unit 1 and the campaign was completed on June 27th, 2017. The total number of spent nuclear fuel assemblies in SFP of Kori Unit-1 is 485 and their discharging date is different respectively. So, decay heat was evaluated considering the actual enrichment, operation history and cooling time of the spent fuel assemblies stored in SFP of the Kori Unit-1. The code used in the evaluation is the ORIGEN-based CAREPOOL system developed by KHNP. Decay heat calculation of PWR fuel is based on ANSI/ANS 5.1-2005, "Decay heat power in light water reactors" and ISO-10645, "Nuclear energy - Light water reactors - Calculation of the decay heat power in nuclear fuels. Also, we considered the contribution of fission products, actinide nuclides, neutron capture and radioactive material in decay heat calculation. CAREPOOL system calculates the individual and total decay heat of all of the spent fuel assemblies in SFP of Kori Unit-1. As a result, the total decay heat generated in SFP on June 28th, 2017 when the spent fuel assemblies were discharged from the reactor core, is estimated to be about 4,185.8 kw and to be about 609.5 kw on September 1st, 2018. It was also estimated that 119.6 kw is generated in 2050 when it is 32 years after the permanent shutdown. Figure 1 shows the trend of total decay heat in SFP of Kori Unit-1.

• 전기의세계
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• 제16권4호
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• pp.41-49
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• 1967

This paper covers an estimation and analysis of generating cost of 350MWe nuclear power plant using a pressurized water reactor on the assumption that such a nuclear power plant would be constructed in Korea in or around 1970. For the evaluation of this generating cost, an extensive study has been conducted based on the current information on operating and costing parameters of light water reactors, particularly those of pressurized water reactors. Based on this study, a total generating cost of 7.29 Mills/Kwh was evaluated by operating the plant at 80% plant factor. For this calculation, a steady state method was introduced. It is considered, therefore, that a total generating cost in the beginning of plant operation would be a little higher than 7.29 Mills/Kwh, which has been calculated in the state of equilibrium.

• 한국주조공학회지
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• 제40권5호
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• pp.129-133
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• 2020

The outcomes of solution annealing and stress corrosion cracking in cold-worked 316L austenitic stainless steel have been studied using x-ray diffraction (XRD) and the slow strain rate test (SSRT) technique. The good compatibility with a high-temperature water environment allows 316L austenitic stainless steel to be widely adopted as an internal structural material in light water reactors. However, stress corrosion cracking (SCC) has recently been highlighted in the stainless steels used in commercial pressurized water reactor (PWR) plants. In this paper, SCC and inter granular cracking (IGC) are discussed on the basis of solution annealing in a chloride environment. It was found that the martensitic contents of cold-worked 316L stainless steel decreased as the solution annealing time was increased at a high temperature. Moreover, mode of SCC was closely related to use of a chloride environment. The results here provide evidence of the vital role of a chloride environment during the SCC of cold-worked 316L.

• 에너지공학
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• 제20권4호
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• pp.298-302
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• 2011

In this study, Catalytic reforming with vapor and biomass gasification was simultaneously performed in a same fixed bed reactor at $600-800^{\circ}C$. Light gases were produced from reformation of the tar (fuel gases) in biomass gasification by using limonite and dolomite, as catalysts. Hydrogen and carbon dioxide are main components in light gases. Hydrogen yields increased with temperature increasing in the range of $650-800^{\circ}C$, because the water shift reaction was promoted by catalyst. The yield of hydrogen gas was increased about 160% under catalyst with the mixture of limonite and dolomite comparing to limonite only.

• Nuclear Engineering and Technology
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• 제52권10호
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• pp.2162-2172
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• 2020

Due to its computational efficiency and geometrical flexibility, the Method of Characteristics (MOC) has been widely used for light water reactor lattice physics analysis. Usually acceleration methods are necessary for MOC to achieve acceptable convergence on practical reactor physics problems. Among them, Coarse Mesh Finite Difference (CMFD) is very popular and can drastically reduce the number of transport iterations. In OpenMOC, CMFD acceleration was implemented but had the limitation of supporting only a uniform CMFD mesh, which would often lead to splitting MOC source regions, thus creating an unnecessary increase in computation and memory use. In this study, CMFD acceleration with a non-uniform Cartesian mesh is implemented into OpenMOC. We also propose a quadratic fit based CMFD prolongation method in the axial direction to further improve the acceleration when multiple MOC source regions are contained in one CMFD coarse mesh. Numerical results are presented to demonstrate the improvement of the CMFD acceleration capability in OpenMOC in terms of both efficiency and stability.

• 공업화학
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• 제10권7호
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• pp.1035-1040
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• 1999

자외선 조사하에서 $TiO_2$를 촉매로 하여 trichloroethylene의 광분해반응을 행하였다. 여러 가지 $TiO_2$ 촉매의 활성을 비교하였고, 반응조건에 따른 광분해 활성을 조사하였다. 또한 빛의 세기에 따른 분해활성과 반응물에 첨가된 물의 영향을 조사하였다. 여러 가지 $TiO_2$ 촉매에서 P-25가 가장 높은 활성을 보였고, anatase형이 rutile형보다 높은 활성을 보였다. 또한 반응물의 유속이 느릴수록 또한 초기농도가 낮을수록 trichloroethylene의 분해 반응 활성은 증가하였고, 산화제로서 공기를 사용하는 것이 효과적이었다. 한편 반응물에 첨가된 물은 촉매의 활성을 감소시켰고, 빛의 세기가 증가할수록 분해 반응속도가 증가하였으나 태양광에 의해서는 분해율이 매우 낮았다. trichloroethylene의 농도가 낮을 경우에는 촉매의 활성저하가 거의 일어나지 않았다.

• 한국세라믹학회지
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• 제45권1호
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• pp.43-47
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• 2008

The photocatalyst of $TiO_2$ coated on a fly ash composites (TCF) was prepared from precipitant dropping method to remove the acetaldehyde by photocatalytic reaction. The TCF were characterized by crystal aize, crystal structure and specific surface area. The photodegradation of acetaldehyde has been investigated using a UV-illuminated fixed photocatalytic reactor with TCF catalyst and P-25 catalyst in gas phase. The effect of photodegradation reaction conditions, such as initial concentration of acetaldehyde, concentration of oxidant in mixed gas and the light intensity on the photodegradation of acetaldehyde were investigated. P-25 catalyst showed the highest photodegradation of acetaldehyde and anatase $TiO_2$ coated TCF showed higher decomposition rate than rutile coated TCF. The photodegradation rate of acetaldehyde increased with the decrease of flow rate, initial concentration of acetaldehyde ($C_i$) and water vapor, however, it was increased with the increas of UV light intensity. The optimum conditions were weight of TCF=10 g, flow rate=50 ml/min $C_i$=100 ppm, concentration of oxygen=20%, concentration of water vapor=100 ppm.

• Nuclear Engineering and Technology
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• 제15권4호
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• pp.267-279
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• 1983

우라늄 및 플루토늄을 핵연료로 이용하고 경수를 감속재로 쓰는 원자로에 대한 해석적 체제를 수립하였다. 이 체제는 두개의 주요 전산코드로 구성되어 있는 바, 하나는 단위격자 세포코드인 KICC로서 이는 GAM및 THERMOS의 이론적인 기초에 여러가지 현상을 적절하게 포현할 수 있는 근사식을 결합한 것이다. 다른 하나는 다차원 확산-연소 방정식코드인 KIDD이다. 이 체제는 다양한 종류의 임계실험로에 대하여 철저한 검증계산을 수행하므로써 그 신뢰성을 입증하였다. 즉 서로 다른 노심구조를 가진 19가지의 비균질 임계실실험로에 대하여 유효증배계수를 계산한 결과 이의 평균치 1.0006, 표준편차 0.0039로서 잘 일치하였다. 또한 우라늄과 플루토늄을 핵 연료로 사용하는 여러종류의 임계로에 대하여 출력분포를 계산하여 측정치와 비교하였으며 계산치는 최대 오차 $\pm$5%이내에서 측정치에 일치하였다. 이러한 사실은 KICC/KIDD체제가 경수로의 해석에 아주 유용한 도구가 됨을 밝혀 준다.