• 한국해양학회지:바다
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• 제12권1호
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• pp.35-42
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• 2007

국내 원자력 발전소의 온배수 배출을 둘러싸고 제기된 각 종 수산업 피해 민원이 발생한지도 20년이 가까워 온다. 온배수에 의한 연안환경 및 수산업 피해를 보다 과학적이고 합리적으로 산정하기 위한 지침이 한국 해양학회, 수산학회 공동의 노력으로 마련되었다. 피해역 산정 방안을 보다 합리적으로 마련하기 위하여 기존의 특정 상승온도 기준을 탈피하고 환경과 생태계의 다양한 영향을 포괄적으로 고려할 수 있는 온배수 영향지수를 제안하였다. 이 영향지수는 UNEP(2002)의 권고안에 따른 지침을 수용하고, 현실성과 경제성 및 미래지향적 특성을 갖출 수 있다. 특정 원자력발전소 현장에 적용 가능한 영향지수의 구현을 위하여 예비 실험의 노력이 요구된다.

• 한국해양학회지:바다
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• 제12권1호
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• pp.43-49
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• 2007

원자력발전소 온배수 영향 조사 과정상 문제점을 평가하고 대안으로서 조사 표준 지침을 제시하였다. 관측이나 온배수 확산 모델링 단독으로 이루어진 지금까지의 방법으로는 시간에 따른 온배수에 의한 수온 분포의 변화를 정량적으로 파악하는데 한계가 있으므로, 관측과 온배수 확산 수치모델링의 상호 보완적인 조사를 병행하는 것이 바람직하다. 현장 관측은 원자력발전소 인근 해역의 모든 자연적 열원의 영향을 고려한 열수지 모형의 개념에 근거한 조사가 중요하며, 수치모델링의 결과를 기준 수온분포로서 활용하고자 할 경우에는 수치모델링에 의한 현상 재현이 통계적 유의수준에 도달한 경우에 한정하도록 하였다. 또한, 과거의 순환 및 확산 모델링의 문제점을 개선하기 위한 대안으로서 표준코드의 개발을 제안하였다.

• 한국환경과학회지
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• 제4권2호
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• pp.169-180
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• 1995

This Daper presents effective simulation of the dispersion of thermal discharge which can be relesed at Boryong power plant. Applied numerical models are finite difference method for hydrodynamic analysis and Masch-model comprised of conditions for ambient current velocity. Application of these models is done in Cheonsu Bay Summing up the results of this study are as follows; 1. It is found that the result for measurements of temperature appears high at southwardly Songdo on flood. The reason is that tidal currents which flowed north direction were accompanied with southwardly dispersed thermal discharge. A minute Particle of thermal Plume has a tendency to dispels inward Deacheon Bay. 2. According to the results of numerical experiment, maximum distance for thermal discharge dispersion appeared 10.8 km at lower part and 8.6 km at upper part with power plant outlet as starting point. 3. Comparative the numerical simulation and Airbone Multispectral Scanner indicated that thermal discharge should be verified separative phenomena. The simulated results were compared with field data set showing good agreement. It is concluded that these model can be simulated well.

• 설비공학논문집
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• 제21권3호
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• pp.157-166
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• 2009

The pulverized coal combustion behavior in the coal fired utility boiler has been investigated with the CFD and process analysis techniques. The used commercial software were CFX and PROATES, and these were coupled each other to get more reliable boundary condition set-up, resulting in more reliable solution. For two cases which were the actual operation condition of A power plant, the calculated values from the coupled CFD and process analysis for thermal energy system were compared with the plant data, and the good agreements were obtained for Case 1 and 2. The calculated temperature distributions on the surface of heat exchangers were compared with the plant data for the steam temperatures across heat exchangers, and these explained the actual operating situation very well. The temperature deviation across the final superheater tube, which was believed to be the main cause of the frequent tube failure, were also explained very well with the calculated distributions of gas temperature and radiation on the plane of the final superheater.

• 환경영향평가
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• 제6권2호
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• pp.81-92
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• 1997

This paper presents the results from the comparison analysis and evaluation between the air pollutant dispersion modeling results and the observation data in the area within a 10 km radius from the Boryong thermal power plants. The observation data used in this study were the air pollutant concentrations which had been continuously measured from 8 locations around the Boryong power plants by TMS(tele-monitoring system) for 3 months from September to November, 1996. The short-term and long-term predictions were carried out using ISC3 model and LPDM(Lagrangian Panicle Dispersion Model). The results of ISC3 modeling in a short-term showed highly as 0.7 in a correlation coefficient, but in a long-term showed just 0.54. On the other hand, LPDM showed 0.78 in a correlation coefficient for a long-term, but in a short-term showed highly value than the observation concentrations.

• 한국태양에너지학회 논문집
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• 제32권5호
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• pp.41-51
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• 2012

Heliostat field is the most important subsystem in the tower type solar thermal power plant since its optical performance affects the total system efficiency most significantly while the construction cost of it is the major part of total construction cost in such a power plant. Thus a well designed heliostat field to maximize the optical efficiency as well as to minimize the land usage is very important. This work presents methodology, procedures and result of heliostat filed design for 200kW solar thermal power plant built recently in Daegu, Korea. A $2{\times}2(m)$ rectangular shaped receiver located at 43(m) high and tilted $28^{\circ}$ toward heliostat field, 450 of heliostats of which the reflective surface is formed by 4 of $1{\times}1(m)$ flat plate mirror facet, and the land area having about $140{\times}120(m)$ size are used to form the heliostat field. A procedure to deploy 450 heliostats in radial staggered nonblocking formation is developed. Also the procedures to compute the cosine effect, intercept ratio, blocking and shading ratio in the field are developed. Finally the heliostat filed is designed by finding the optimal radial distance and azimuthal spacing in radial staggered nonblocking formation such that the designed heliostat field optical efficiency could be maximized. The designed heliostat field has 77% of annual average optical efficiency, which is obtained by annually averaging the optical efficiencies computed between the time of where sun elevation angle becomes $10^{\circ}$ after sunrise and the time of where sun elevation angle becomes $10^{\circ}$ before sunset in each day.

• 한국연소학회지
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• 제18권3호
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• pp.44-53
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• 2013

In this study, the economic evaluation for imported coals was conducted for power plant based on thermo-dynamical performance analysis. The number of coal types considered was 1,755 imported by five power generation companies in Korea during the 2010-2012. The higher heating value (HHV) of the coals ranged 4,000-6,500 kcal/kg, mostly sub-bituminous. The 1D thermo-dynamical performance modeling was performed for a 500 MWe standard power plant using PROATES code. It was founded that the low rank coals had negative effects on the plant efficiency mainly due to the increased heat loss by moisture, hydrogen and flue gas. Based on the performance analysis, the economic performance of the coals was evaluated. The apparent price of low-rank coals tended to be significantly lower than design coal; for example, the unit price of coal with a HHV of 4,000 kcal/kg was 57% of the reference coal having 6,080 kcal/kg. Considering the negative effects leading to a decrease in the thermal performance, heating value compensation, and increased parasite load, the corrected unit cost for the coal with 4,000 kcal/kg was 90.7% of the reference coal. Overall, the cost saving by imported coals was not high as expected.

• 환경생물
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• 제22권3호
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• pp.426-437
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• 2004

To understand the phytoplankton community in adjacent waters of Ulchin nuclear power plant (UNPP), abundance and the size fractionated $chl-\alpha$ concentrations were evaluated through seasonal interval sampling from April 2003 to February 2004. A total of 211 different phytoplankton species was observed and mean abundance of phytoplankton in each study period ranged from 244,286 to 1,221,779 cells $L^{-1}$. The contributions of microplankton $(>20\mu{m})$ to total phytoplankton abundance ranged from 42.5 to 83.6% (average 66.1%) and those of nanoplankton $(>20\mu{m})$ ranged from 16.4 to 57.5% (average 33.9%). Total chl-$\alpha$ concentrations of phytoplankton ranged from 0.52 to $2.26\mu{g}\;L^{-1}$. The contribution of chl-$\alpha$ concentrations of microplankton was higher than that of nano- and picoplankton through the study period with exception of July 2008. The results of abundances and $chl-\alpha$ concentrations suggest that microplankton has an important role in adjacent waters of UNPP. The diminution of abundances and $chl-\alpha$ concentrations of phytoplankton was observed after passage through the cooling water system, but it was gradually recovered by mixing with the ambient waters. Our results suggested that the influence of thermal discharges on phytoplankton should be restricted within narrow limits around outlet area of thermal effluents.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.625-630
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• 1987

Technology associated with power plant control system has been heavily rely on foreign technology. The main reason is that the system has tomaintain stringent reliability and stability. Localization of this system can be started from localization of modules necessary for maintenance and repair in hydraulic and thermal power plant. Gradually and eventually system engineering capability can be built up to design and develop nuclear power plant control system through technology accumulation. Methods are presented to achieve this goal.

• KEPCO Journal on Electric Power and Energy
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• 제7권1호
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• pp.125-128
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• 2021

This paper presents the root cause failure analysis of the circulating water pump in the 560 MW thermal power plant. A fractured austenitic stainless-steel shaft operated for 24 years was examined. Fracture morphology was investigated by micro and macro-fractographic analysis. The metallurgical analyses including chemical analysis, metallography and hardness testing were performed. The analysis reveals that the pump shaft was fractured due to the reverse bending load with combination of rotating bending load. Corrective actions for plant operator was recommended based on the analysis.