Methodology for determining of the weighted mean coolant temperature in the primary circuit hot legs of WWER-1000 reactor plants
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Yu. V. Saunin
Abstract
At WWER-1000 NPPs, as well as at PWR NPPs, there is a problem of determining the correct weighted mean coolant temperature in the primary circuit hot legs based on the measuring channels information. The problem is caused by the coolant temperature stratification. The technical documentation for engineering support and maintenance of I&C systems does not provide any regulatory guidelines to consider this effect. Therefore, it is very important to represent a new methodology for determining the weighted mean coolant temperature in the primary circuit hot legs of the WWER-1000 reactor plants. The given paper presents the basic preconditions and approaches applied during the methodology development. They were worked out on the basis of the executed numerical and experimental research taking into account the analysis of the extensive material obtained by the authors from full-scale tests during the commissioning of WWER-1000 power units, as well as operational data obtained from several power units with different fuel loadings.
Kurzfassung
Sowohl bei WWER-1000-Reaktoren als auch bei Druckwasserreaktoren ist die Bestimmung einer gewichteten mittleren Kühlmitteltemperatur in den heißen Strängen des Primärkreislaufs allein auf Basis der Messkanalinformationen schwierig aufgrund der Temperaturschichtungen im Kühlmittel. Es gibt keine Berechnungsvorgaben zur Berücksichtigung dieser Temperaturschichtungen bei der Berechnung der mittleren Kühlmitteltemperatur. In diesem Beitrag wird eine Methode vorgestellt, die für heiße Stränge in WWER-1000-Reaktoren angewendet werden kann. Es werden die grundlegenden Annahmen und Bedingungen vorgestellt und die Entwicklung der Methode beschrieben. Sie basiert auf numerischen und experimentellen Arbeiten und berücksichtigt die Erfahrungen, die die Autoren sowohl bei Inbetriebnahmen von WWER-1000-Reaktoren als auch beim Betrieb dieser Anlagen gewonnen haben.
References
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© 2016, Carl Hanser Verlag, München
Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Editorial
- Research on the reactor physics and reactor safety of VVER reactors – AER Symposium 2015
- Technical Contributions/Fachbeiträge
- Monte-Carlo code calculation of 3D reactor core model with usage of burnt fuel isotopic compositions, obtained by engineering codes
- Xenon instability study of large core Monte Carlo calculations
- Error detection in core loading in the condition of asymmetrical distribution of power
- New models in VERONA 7.0 system
- Methodology for determining of the weighted mean coolant temperature in the primary circuit hot legs of WWER-1000 reactor plants
- Verification of three-dimensional neutron kinetics model of TRAP-KS code regarding reactivity variations
- Aspects of using a best-estimate approach for VVER safety analysis in reactivity initiated accidents
- Qualification of coupled 3D neutron kinetic/thermal hydraulic code systems by the calculation of a VVER-440 benchmark – re-connection of an isolated loop
- Uncertainties of the KIKO3D-ATHLET calculations using the Kalinin-3 benchmark (Phase II) data
- Coupled code analysis of uncertainty and sensitivity of Kalinin-3 benchmark
- Efficient introduction of natural uranium and thorium into nuclear energy system
- Economical aspects of multiple plutonium and uranium recycling in VVER reactors
- Neutronic analysis of absorbing materials for the control rod system in reactor ALLEGRO
- Uncertainty analysis and flow measurements in an experimental mock-up of a molten salt reactor concept
Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Editorial
- Research on the reactor physics and reactor safety of VVER reactors – AER Symposium 2015
- Technical Contributions/Fachbeiträge
- Monte-Carlo code calculation of 3D reactor core model with usage of burnt fuel isotopic compositions, obtained by engineering codes
- Xenon instability study of large core Monte Carlo calculations
- Error detection in core loading in the condition of asymmetrical distribution of power
- New models in VERONA 7.0 system
- Methodology for determining of the weighted mean coolant temperature in the primary circuit hot legs of WWER-1000 reactor plants
- Verification of three-dimensional neutron kinetics model of TRAP-KS code regarding reactivity variations
- Aspects of using a best-estimate approach for VVER safety analysis in reactivity initiated accidents
- Qualification of coupled 3D neutron kinetic/thermal hydraulic code systems by the calculation of a VVER-440 benchmark – re-connection of an isolated loop
- Uncertainties of the KIKO3D-ATHLET calculations using the Kalinin-3 benchmark (Phase II) data
- Coupled code analysis of uncertainty and sensitivity of Kalinin-3 benchmark
- Efficient introduction of natural uranium and thorium into nuclear energy system
- Economical aspects of multiple plutonium and uranium recycling in VVER reactors
- Neutronic analysis of absorbing materials for the control rod system in reactor ALLEGRO
- Uncertainty analysis and flow measurements in an experimental mock-up of a molten salt reactor concept
