• 한국압력기기공학회 논문집
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• 제7권2호
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• pp.14-20
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• 2011

The end of design lifetime for Wolsong unit 1 will be reached on 20th November in 2012. So the license renewal documents for the continuous operation of Wolsong unit 1 is under reviewing now. Major components of primary system such as pressure tubes, feeder pipes including delayed neutron monitoring system tubing are being replaced and many components of secondary system are also being repaired. In this paper, the assessment on the wear degradation of delayed neutron monitoring system tubing(on the other hand, DN tube was called) was performed for the ageing management of the same component. The wear defects of this component was one of causes that resulted in heavy water leakage accidents. Therefore design specifications of Wolsong uint 1 and heavy water leakage accidents of pressurized heavy water reactors were reviewed and causes of wear defect for DN tubes were analyzed. Wear propagation equations based on the heavy water leakage history were made and the proper repairing time was possible to be expected if the continued operation was considered. Finally design change items of DN tubes that were conducted for the long term operation of Wolsong unit 1 are introduced.

• 한국압력기기공학회 논문집
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• 제6권2호
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• pp.28-33
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• 2010

As a part of license renewal for the continued operation of Wolsong unit 1, the periodic safety review report was submitted near the end of design lifetime, 2012, and now is under reviewing. Major components of primary system such as pressure tubes, feeder pipes and so on are being replaced and many components of secondary system are also being repaired. So the license renewal of Wolsong unit 1 is expected to be acquired without significant issues. But on the other hand, steam generators of Wolsong unit 1 had the good performance and therefore the replacement and repair for the steam generator are not needed. Recently it is reported that some cracks were detected in a few of european steam generator with Alloy 800 tubes and the cause of cracks was the outer diameter stress corrosion cracking(ODSCC) due to the concentration of chemical impurities on the outer surface of tube. Accordingly the overall review on this issue was performed. The long-term operation is likely to results to form the concentration mechanism for the tube corrosion as the sludge build-up in the secondary side of steam generator and the crack in the crevice between tube and tube-sheet and expansion transitions is apt to be occurred. In this paper, the history of steam generator inspection and operation of Wolsong unit 1 are reviewed and the reliability of steam generator tube is evaluated and the steam generator aging management program for Wolsong unit 1 is introduced.

• Journal of Radiation Protection and Research
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• 제28권4호
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• pp.337-342
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• 2003

On a basis of the washout model and concentrations of anthropogenic tritium in rainwater around the Wolsong site, the washout coefficients of tritium by rainwater were calculated, and the validity of washout deposition model are estimated. As the result of that, the washout coefficients in 10 sampling stations around Wolsong site were in the range of $2.9{\times}10^{-5}\;-\;16{\times}10^{-5}\;s^{-1}$ with the mean value of $7.21{\times}10^{-5}\;s^{-1}$. The validity of the washout deposition model was confirmed by comparing the observed data with the calculated ones.

• Journal of Radiation Protection and Research
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• 제17권2호
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• pp.37-48
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• 1992

월성 원자력 발전소 2호기의 1차 종단 및 측면 차폐 계통의 각 차폐체에 대한 100% 출력 가동시 핵에너지 축적을 해석을 ANISN 코드를 이용하여 수행하였다. 본 해석 결과는 월성원자력 발전소 2호기 계통 설계시 고려 사항으로 이용될 수 있다.

• Nuclear Engineering and Technology
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• 제28권4호
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• pp.423-430
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• 1996

The improved and advanced Annulus Gas System(AGS) has been developed for Wolsong 2 to satisfy the requirements of the regulatory body. The Atomic Energy Control Board(AECB) required a shorter detection time following a small leak from a pressure tube and/or calandria tube. This paper describes licensing requirements, functional requirements and detail design description for the AGS. The Wolsong unit No. 1 AGS was designed to operate as a stagnant system normally requiring only pressure regulation and having provisions for purging. no improved AGS involves the adoption of gas recirculation in AGS, duplication of dew point indicators with additional instrumentation and sampling provisions to prompt operator action. The improved system operates in the recirculation mode with continuous dew point measurement for leak detection. An AGS with improved detection instrumentation is provided.

• Nuclear Engineering and Technology
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• 제30권2호
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• pp.83-90
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• 1998

To predict effects of seismic isolation, seismic isolation bearings were applied to the Wolsong reactor building and the analytical study was performed. For this study, the Wolsong reactor building was modeled using lumped masses and beam elements. Design Basis Earthquake with a ground acceleration of 0.2g was applied. And then, the behavior of the isolated structure was compared with that of the unisolated structure. The horizontal response acceleration at the top of the unisolated reactor building was 0.99g, while that of the isolated one was 0.14g(15% damping) and the acceleration response along the height of the structure was constant. The maximum displacement of the unisolated structure was 8.3mm, while that of the isolated structure was 66mm. The application of isolation bearings on the reactor building reduces seismic loads but increases the displacement of the structure on a large scale. Therefore, when using isolation bearings, the reactor building and BOP should be located on a common mat to cover the large displcement.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(1)
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• pp.272-277
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• 1995

The current direction of emergency procedures for CANDU reactors is reviewed and compared based on scope, methodology and format preponderantly, and an attempt is made to integrate these procedures. As a result, a recommendation for Wolsong 2, 3 & 4 emergency procedures is presented as event-specific procedures, generic procedure and whose format is combination of logic diagram and technical basis document.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.484-490
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• 2003

WTRF 가동에 따른 월성원전 삼중수소 방출량을 예측하였다. 호기별 WTRF 처리량 변화에 따른 월성원전 감속재와 냉각재 삼중수소 농도변화를 예측하였으며, 이로부터 삼중수소 방출량을 계산하였다. WTRF 가동에 의해 2013년에는 감속재 삼중수소 농도는 적어도 10 Ci/kg-$D_2O$ 이하로 떨어지며, 이때 연간 삼중수소 방출량은 WTRF 가동초기보다 약 25% 정도로 감소하는 것으로 나타났다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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• pp.163-168
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• 1996

Simulations of Wolsong-1 Phase-B commissioning measurements have been performed, as part of the program to validate WIMS-AECL lattice cell calculations for application to CANDU reactor simulations in RFSP. A required component of these simulations is the calculation of incremental cross sections representing reactivity control devices in the reactor. The incremental cross section properties of the Wolsong-1 adjusters, Mechanical Control Absorbers (MCA) and liquid Zone Control Units (ZCU) are based on the WIMS-AECL/MULTICELL modelling methods and the results are compared with those of WIMS-AECL/DRAGON-2 modelling methods.

• Nuclear Engineering and Technology
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• 제28권6호
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• pp.594-601
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• 1996

To assure quality of safety critical software, software should be developed in accordance with software development procedures and rigorous software verification and validation should be performed. Software verification is the formal act of reviewing, testing or checking, and documenting whether software components comply with the specified requirements for a particular stage of the development phase [1]. New software verification methodology was developed and was applied to the Shutdown System No. 1 and 2(SDS1,2) for Wolsong 2, 3 and 4 nuclear power plants by Korea Atomic Energy Research Institute(KAERI) and Atomic Energy of Canada Limited(AECL) in order to satisfy new regulation requirements of Atomic Energy Control Board(AECB). Software verification methodology applied to SDS1 for Wolsong 2, 3 and 4 project will be described in this paper. Some errors were found by this methodology during the software development for SDS1 and were corrected by software designer. Output from Wolsong 2, 3 and 4 project have demonstrated that the use of this methodology results in a high quality, cost-effective product.