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Daejeon, South Korea

Korea Nuclear Fuel or KNF is a South Korean public enterprise established in 1982 to provide high quality nuclear fuel. It provides nuclear fuels to 20 nuclear power plants in South Korea. The price of the nuclear fuel provided by the company accounts for 60% of the average international price. Wikipedia.

Ryu S.-H.,Korea Nuclear Fuel Co. | Park G.-C.,Seoul National University
Nuclear Engineering and Design | Year: 2011

Droplets are generated at the interface of annular flow due to an interaction between a liquid film and gas core flow. Therefore, knowledge of the interfacial wave structure is essential for making an accurate prediction of the amount of entrained droplets. A new droplet entrainment model was proposed based on the force balance of interfacial waves in vertical annular flow. An analytic wave shape function was developed reflecting the detailed experimental findings, and was used in the development of a new model. The model was validated using the experimental data reported by Hewitt and Pulling at low pressures and by Keeys et al. at high pressures, which had been performed in adiabatic vertical tubes. The root-mean-square error of the prediction of the amount of entrainment was approximately 27% when the model was implemented into COBRA-TF code, which is approximately 23% less than that determined by the Würtz model. The models proposed by Okawa et al. and Stevanovic et al. were also implemented into COBRA-TF and compared with the proposed model. © 2011 Published by Elsevier B.V. Source

Cho M.S.,Korea Atomic Energy Research Institute | Lee S.J.,Korea Nuclear Fuel Co. | Lee Y.S.,Daejeon University
Transactions of the American Nuclear Society | Year: 2010

Thermal load simulation and verification experiments of a very high temperature irradiation of TRISO coated particle fuels in HANARO research reactor were carried out to verify the feasibility of irradiation rod designs. Results of the experiments were used to develop and verify a COMSOL based finite element heat transfer model that will be used as a basis for an optimum design of an irradiation test rod. Source

Kim Y.-S.,Hanyang University | Jeong Y.-H.,Korea Atomic Energy Research Institute | Son S.-B.,Korea Nuclear Fuel Co.
Journal of Nuclear Materials | Year: 2014

The effects of dissolved hydrogen on oxide phase transformation and micro-structural changes during zirconium oxide growth were investigated using Raman spectroscopy and Transmission Electron Microscopy (TEM). Raman spectra measurements show that tetragonal zirconia develops during oxide growth and a fraction of the phase in pre-hydrided alloy is consistently lower than that of an un-hydrided one. This was observed identically in both Zircaloy-4 and Zr-1.5Nb alloys. TEM analysis at the metal-oxide interface support that the Raman spectra changes resulted from micro-structural changes. These results suggest that the dissolved hydrogen may cause meta-stabilization of the tetragonal phase oxide grown at the metal-oxide interface, probably by relaxing the compressive stress built up at the interface, or by modifying the stress distribution over the interface. The relaxation or modification possibly comes from the mitigation of the lattice incoherency between the metal and the oxide at the interface that is the origin of the compressive stress build-up. © 2013 Elsevier B.V. All rights reserved. Source

Korea Nuclear Fuel Co. | Date: 2013-10-31

Disclosed therein are an apparatus for and a method of welding a flange to a guide thimble tube in a nuclear fuel assembly. The automatic welding apparatus includes a welding unit located on an axially conveying line of a tube for welding a surface of the tube inserted thereinto and a surface of a flange, a flange supplying unit for supplying the flange at a tube inlet of the welding unit onto the axially conveying line, and a conveying unit mounted on the axially conveying line in such a way as to move the tube and the flange on the axially conveying line, so that they are inserted into and drawn from the welding unit.

Ha S.J.,Korea Electric Power Research Institute | Park C.E.,KEPCO Engineering and Construction Company Inc. | Kim K.D.,Korea Atomic Energy Research Institute | Ban C.H.,Korea Nuclear Fuel Co.
Nuclear Engineering and Technology | Year: 2011

The Korean nuclear industry is developing a thermal-hydraulic analysis code for safety analysis of pressurized water reactors (PWRs). The new code is called the Safety and Performance Analysis Code for Nuclear Power Plants (SPACE). The SPACE code adopts advanced physical modeling of two-phase flows, mainly two-fluid three-field models which comprise gas, continuous liquid, and droplet fields and has the capability to simulate 3D effects by the use of structured and/or nonstructured meshes. The programming language for the SPACE code is C++ for object-oriented code architecture. The SPACE code will replace outdated vendor supplied codes and will be used for the safety analysis of operating PWRs and the design of advanced reactors. This paper describes the overall features of the SPACE code and shows the code assessment results for several conceptual and separate effect test problems. Source

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