• 제목/요약/키워드: EPRI

검색결과 166건 처리시간 0.017초

EPRI 최신 연구동향 및 멤버십 활용방안 (Introduction to EPRI's Energy Researches and How to use Membership)

  • 김충효
    • KEPCO Journal on Electric Power and Energy
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    • 제7권1호
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    • pp.179-194
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    • 2021
  • EPRI 의 설립배경과 현황, 최근 R&D 연구 동향인 Low Carbon Resource Initiative (LCRI)와 Electrification 에 대하여 소개하고, 멤버십 혜택을 통해 EPRI 활용을 극대화할 수 있는 방안을 제시한다.

원전용 디지털 인디케이터의 검증 규정 EPRI TR-106439에 관한 고찰 (A Study on EPRI TR-106439 for Digital Indicator of Nuclear Power Plant)

  • 배창호;이동희;김규로;장중순
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제14권4호
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    • pp.248-255
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    • 2014
  • Nuclear power plants may use commercial grade items if they can pass special tests or inspections, which is called Commercial Grade Item Dedication (CGID). Digital items, however, should follow EPRI TR-106439 to be applied to nuclear power plants. This paper explains the scheme and requirements of the EPRI TR-106439 and introduces some guidelines. Firstly, in order to clarify requirements of the EPRI TR-106439, code interpretation is performed. And through case study of digital indicator, limitations of EPRI TR-106439 are mentioned, and improvement direction is proposed.

EPRI의 예방정비기초자료에 근거한 원전 증기터빈의 예방정비기준 개발 (Development the Preventive Maintenance Template of the Nuclear Steam Turbine based on EPRI PMBD)

  • 이병학;이혁순
    • 한국압력기기공학회 논문집
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    • 제6권1호
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    • pp.1-8
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    • 2010
  • The existing maintenance program is focused on time-based maintenance to inspect and repair components according to maintenance period, rather than condition-based maintenance or predictive maintenance. The preventive maintenance template of the steam turbine has been developed for optimizing maintenance procedure and improving reliability and availability of the steam turbine of nuclear power plants based on EPRI PM template methodology and EPRI technical reports about preventive maintenance.

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Utilization of EPRI ChemWorks tools for PWR shutdown chemistry evolution modeling

  • Jinsoo Choi;Cho-Rong Kim;Yong-Sang Cho;Hyuk-chul Kwon;Kyu-Min Song
    • Nuclear Engineering and Technology
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    • 제55권10호
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    • pp.3543-3548
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    • 2023
  • Shutdown chemistry evolution is performed in nuclear power plants at each refueling outage (RFO) to establish safe conditions to open system and minimize inventory of corrosion products in the reactor coolant system (RCS). After hydrogen peroxide is added to RCS during shutdown chemistry evolution, corrosion products are released and are removed by filters and ion exchange resins in the chemical volume control system (CVCS). Shutdown chemistry evolution including RCS clean-up time to remove released corrosion products impacts the critical path schedule during RFOs. The estimation of clean-up time prior to RFO can provide more reliable actions for RCS clean-up operations and transients to operators during shutdown chemistry. Electric Power Research Institute (EPRI) shutdown calculator (SDC) enables to provide clean-up time by Co-58 peak activity through operational data from nuclear power plants (NPPs). In this study, we have investigated the results of EPRI SDC by shutdown chemistry data of Co-58 activity using NPP data from previous cycles and modeled the estimated clean-up time by EPRI SDC using average Co-58 activity of the NPP. We selected two RFO data from the NPP to evaluate EPRI SDC results using the purification time to reach to 1.3 mCi/cc of Co-58 after hydrogen peroxide addition. Comparing two RFO data, the similar purification time between actual and computed data by EPRI SDC, 0.92 and 1.74 h respectively, was observed with the deviation of 3.7-7.2%. As the modeling the estimated clean-up time, we calculated average Co-58 peak concentration for normal cycles after cycle 10 and applied two-sigma (2σ, 95.4%) for predicted Co-58 peak concentration as upper and lower values compared to the average data. For the verification of modeling, shutdown chemistry data for RFO 17 was used. Predicted RCS clean-up time with lower and upper values was between 21.05 and 27.58 h, and clean-up time for RFO 17 was 24.75 h, within the predicted time band. Therefore, our calculated modeling band was validated. This approach can be identified that the advantage of the modeling for clean-up time with SDC is that the primary prediction of shutdown chemistry plans can be performed more reliably during shutdown chemistry. This research can contribute to improving the efficiency and safety of shutdown chemistry evolution in nuclear power plants.

Assessment of COBRA-TF for Critical Heat Flux

  • Chun, Tae-Hyun;Lim, Jong-Sun;Motoaki Okazaki
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(2)
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    • pp.75-81
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    • 1996
  • COBRA-TF is a two fluid, three field subchannel code. Three fields are continuous vapor, continuous liquid and droplet. Some assessments are conducted to validate the related models and to estimate a code ability through dryout and post-CHF experiment in a tube and DNB test in rod bundles. It turned out form dryout and post-CHF experiment that the predicted dryout locations and wall temperature profiles are in close agreement with the experiments. On the other hand, DNB prediction of COBRA-TF are performed for two kinds of rod bundles along with EPRI CHF correlation. To estimate its performance COBRA-IV of homogeneous model is also run for the same data. The results say that COBRA-TF/EPRI is better in DNB prediction than COBRA-IV/EPRI. In addition the thermal-hydraulic behaviors due to the different two-phase flow models are presented at the condition of CHF.

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배관 내 축방향 반타원 표면균열에 대한 비선형 파괴역학 해석 (Non-Linear Fracture Mechanics Analyses for Axial Semi-Elliptical Surface Cracked Pipes)

  • 김진수;김윤재;김영진
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.143-148
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    • 2003
  • This paper provides two types of engineering J estimation equations for cylinders with finite internal axial surface cracks under internal pressure. The first type is the so-called GE/EPRI type J estimation equation based on Ramberg-Osgood materials. Based on detailed 3-D FE results the GE/EPRI-type J estimation equation along the crack front is proposed and validated for Ramberg-Osgood materials. For more general application, the developed GE/EPRI-type solutions are then re-formulated based on the reference stress concept. The proposed reference stress based J estimation equation has good agreement between the FE results and the proposed reference stress based J estimation provides confidence in the use of the proposed method for elastic-plastic fracture mechanics of pressurised piping

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축전지가 필요치 않은 무정전 전원장치 (Battery Free UPS using Fly wheel Technologies)

  • 황용하
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 추계학술대회 논문집 전기설비전문위원
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    • pp.114-121
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    • 2004
  • 에너지 저장 방식은 양질의 전원이 요구되는 중요 부하를 보호하기 위해 꾸준히 개발되어 왔다. 그 중 현재 가장 관심 있는 분야 중 하나인 것은 bridging power 시스템이다. 이 bridging power 시스템은 25kW에서부터 2,500k범위까지 다양한 제품이 용도에 맞게 출시되고 있다. Bridging Power 방식들은 4가지로 크게 요약될 수 있다. 즉, 저/고속의 플라이휠, 배터리, ultra capacitors 및 magnetic storage 기술 등이다. 이 논문은 bridging power 시스템의 개요에 대해 설명하고, 주요 기능 감시 시스템의 특징 및 장/단점에 대해 기술했으며, 현재 EPRI와 EPRI PEAC과 함께 TVA Public Power Institute가 제공하는 R&D 활동에 대해 요약하였다.

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