• Proceedings of the Korean Nuclear Society Conference
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• 2003.05a
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• pp.54.2-54.2
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• 2003

• Nuclear Engineering and Technology
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• v.37 no.6
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• pp.605-610
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• 2005

A method to estimate the relative sensitivity of a self-powered rhodium detector for an upcoming cycle is developed by combining the rhodium depletion data from a nuclear design with the site measurement data. This method can be used both by nuclear power plant designers and by site staffs of Korean standard nuclear power plants for determining which rhodium detectors should be replaced during overhauls.

• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3353-3360
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• 2022

Using data from the design earthquake of the Korean standard nuclear power plant, seismic analyses of a fuel assembly are conducted in this study. The modal characteristics are used to develop an input deck for the seismic analysis. With a time history analysis, the responses of the fuel assembly in the event of an earthquake are obtained. In particular, the displacement, velocity, and acceleration responses at the center location of the fuel assembly are obtained in the time domain, with these outcomes then used for a detailed structural analysis of the fuel rods in the ensuing analyses. The response spectra are also generated to determine the response characteristics in the frequency domain. The structural integrity of the fuel assembly can be ensured through this type of time history analysis considering the input excitations of various earthquakes considered in the design.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.685-686
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• 2008

For the purpose of reducing the plant trip/transient by the failure of a single component during plant operation or maintenance, the list of critical components with Single Point Vulnerability (SPV) on KSNP (Korean Standard Nuclear Power Plant), the standardized methodology of SPV evaluation and the plan to improve reliability of the equipment have been established. In addition, SPV component lists for the other domestic operating Nuclear Power Plants have been made, and the proper procedure for SPV management will be developed.

• Journal of Mechanical Science and Technology
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• v.18 no.1
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• pp.74-81
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• 2004

The KSNP Steam Generators (Youngkwang Unit 3 and 4, Ulchin Unit 3 and 4) have a problem of U-tube fretting wear due to Flow Induced Vibration (FIV). In particular, the wear is localized and concentrated in a small area of upper part of U-bend in the Central Cavity region. The region has some conditions susceptible to the FIV, which are high flow velocity, high void fraction, and long unsupported span. Even though the FIV could be occurred by many mechanisms, the main mechanism would be fluid-elastic instability, or turbulent excitation. To remedy the problem, Eggcrate Flow Distribution Plate (EFDP) was installed in the Central Cavity region or Ulchin Unit 5 and 6 steam generators, so that it reduces the flow velocity in the region to a certain level. However, the cause of the FIV and the effectiveness of the EFDP was not thoroughly studied and checked. In this study, therefore the Stability Ratio (SR), which is the ratio of the actual velocity to the critical velocity, was compared between the value before the installation of EFDP and that after. Also the possibility of fluid-elastic instability of KSNP steam generator and the effectiveness of EFDP were checked based on the ATHOS3 code calculation and the Pettigrew's experimental results. The calculated results were plotted in a fluid-elastic instability criteria-diagram (Pettigrew, 1998, Fig. 9). The plotted result showed that KSNP steam generator with EFDP had the margin of Fluid-Elastic Instability by almost 25％.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1221-1222
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• 2005

Interface control activities during the nuclear power plant (NPP) construction and operation have been reviewed for enhancing the safety of NPP. The primary focus of the study is given on analysis of lessons learned from the recent significant events of Korean Standard Nuclear Power plant (KSNP), such as a series of break-off of thermal sleeves at YGN 5 & 6 and radioactivity leak at YGN 5, in respect of interface control. Based on the results of the analysis, this study recommends measures for the improvement of interface control among utility and technical supporting organizations (TSO), and suggests new regulatory systems, such as reporting of safety significant non-conformances, to effectively verify the adequacy of interface control activities during construction and operation of NPPs.

• Journal of the Korean Society of Safety
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• v.26 no.6
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• pp.85-89
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• 2011

Component reliability data were analyzed by using PRinS(Plant Reliability data information System) based on the latest operating experiences of eight KSNPs(Korea Standard Nuclear Power plants), and these new data were applied to the KSNP PSA models. In addition, the existing PSA models were revised for reflecting as-built and as-operated plant conditions. As a result of newly performing PSA in this paper, CDF and LERF were estimated 26.1% and 18.2% lower than the existing values, respectively. It was identified that the risk measures decreased not because of revising the models but because of applying the new component reliability data. The result and the method of this paper could be used when generating plant specific data and performing the living PSA in the future.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2275-2277
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• 2004

Korea Next Generation Reactor(KNGR) is in the midst of being developed and will exceed Korea Standard Nuclear Power Plant(KSNP) economically. Domestic Instrumentation and Control(I&C) systems shall be applied to KNGR and the development of Control Element Drive Mechanism Control System(CEDMCS) considered as an essential part in nuclear I&C system will be dealt with in this paper. The newly developed CEDMCS has the control cabinet using the nuclear Distributed Control System(DCS) made in Korea and the power cabinet produced by our research institute and interfaced with the DCS control cabinet.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.610-616
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• 2003

Recently, the common concern of nuclear power industry in the development of technology mitigating and preventing the aging of steam generator tubes prevails, because the trends of steam generator flaws at Uljin unit #1,2 and KSNP(Korea Standard Nuclear Power Plant) impose a burden on the operation of nuclear power plant. While the regulatory agency is demanding the establishment of the advanced general performance maintenance system, the steam generator management program adapting advanced technology is being developed which may comply with EPRI PWR SG Guidelines based on NEI 97-06 ‘ General Guidelines including all the maintenance aspects consist of the tube integrity assessment criteria, repair limit, allowable leakage level, water chemistry will be composed in order to obtain the approval of regulatory agency and be applied to Nuclear power plant early 2005. This presentation is to introduce maintenance state including SG tube degradation and main contents of advanced SG management program being developed, and futhermore update present and future plan, and estimate the alternation after the completion.

• Journal of Information Technology Applications and Management
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• v.11 no.4
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• pp.35-47
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• 2004

The nuclear design analysis requires time-consuming and erroneous model-input preparation. code run. output analysis and quality assurance process. To reduce human effort and improve design quality and productivity. Innovative Design Processor (IDP) is being developed. Two basic principles of IDP are the document-oriented desigll and the web-based design. The document-oriented design is that. if the designer writes a design document called active document and feeds it to a special program. the final document with complete analysis. table and plots is made automatically. The active documents can be written with Microsoft Word or created automatically on the web. which is another framework of IDP. Using the proper mix-up of server side and client side programming under the LAMP (Linux/Apache/MySQL/PHP) environment. it e design process on the web is modeled as a design wizard style so that even a novice designer makes the design document easily. This automation using the IDP is now being implemented for all the reload design of Korea Standard Nuclear Power Plant (KSNP) type PWRs. The introduction of this process will allow large reduction in all reload design efforts of KSNP and provide a platform for design and R&D tasks of KNFC.