Definition of conservative conditions for RIA analysis in the modernized RBMK reactor core
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R. Pabarcius
Abstract
During the past decade a number of modifications were implemented in the Ignalina NPP reactors cores. A significant reactor core loading change allowed increasing the safety level of the plant. During previously performed safety analyses a question has arisen concerning conservatism of used initial boundary conditions for investigation. The impact of different axial fuel burn-up and power-density profiles in the reactor core on modelling results as well as estimation of conservative conditions for the analysis of reactivity initiated accidents in the modernized RBMK-1500 reactor core were analyzed. The results of the investigations are presented in this paper. Simulation results show that previously used initial boundary conditions for modelling of accidents are changing due to a change of composition and loading in the modernized RBMK reactor core.
Kurzfassung
Während des vergangenen Jahrzehnts wurden einige Änderungen in den Reaktorkernen des Kernkraftwerks Ignalina ausgeführt. Eine wesentliche Änderung in der Kernbeladung ermöglichte die Erhöhung der Sicherheit des Kernkraftwerks. Während früherer Sicherheitsanalysen hatte sich die Frage nach der Konservativität der anfänglich benutzten Randbedingungen für die durchgeführten Untersuchungen gestellt. Sowohl der Einfluss des unterschiedlichen axialen Brennstoff-Abbrands und der Leistungsdichte im Reaktorkern auf Modellierungsergebnisse als auch die Bewertung konservativer Bedingungen für die Analyse von Reaktivitätsstörfällen im modernisierten RBMK-1500-Reaktorkern wurden analysiert. Die Ergebnisse dieser Untersuchungen werden in diesem Beitrag vorgestellt. Die Simulationsergebnisse zeigen, dass sich die früher verwendeten anfänglichen Randbedingungen für die Modellierung von Störfällen aufgrund veränderter Zusammensetzung und Beladung im modernisierten RBMK-Reaktorkern verändern.
References
1 Accident analysis for nuclear power plants with graphite moderated boiling water RBMK reactors, Safety Reports Series No. 43, 2005, IAEA, ViennaSuche in Google Scholar
2 Safety Analysis Report for Unit 1, 1996, Ignalina NPPSuche in Google Scholar
3 Safety Analysis Report for INPP Unit 2, 2002, IgnalinaNPPSuche in Google Scholar
4 Final safety justification for Diverse Shutdown System for INPP Unit 2, Vol. 3. Chap. 3. Accident analysis, DS&S, 2005Suche in Google Scholar
5 Accident Analysis for Nuclear Power Plants, Safety Reports Series No. 23, 2002, IAEA, ViennaSuche in Google Scholar
6 Bubelis, E.; Pabarcius, R.; Langenbuch, S.; Clemente, M.; Velkov, K.: Analysis of Nuclear Characteristics of Ignalina-RBMK Using New Fuel Elements with 2.4 % Enrichment and Erbium. In: Proc. of Annual Meeting on Nuclear Technology 99, May 18–21, 1999, Karlsruhe, GermanySuche in Google Scholar
7 Bubelis, E.; Pabarcius, R.; Langenbuch, S.; Clemente, M.: Analysis of Nuclear Characteristics of Ignalina-RBMK-1500 Reactors Using New Uranium-Erbium of 2.6 % enrichment. In: Proc. of Annual Meeting on Nuclear Technology 2003, May 18–21, 2003, Berlin, GermanySuche in Google Scholar
8 Langenbuch, S.; Maurer, W.; Werner, W.: Coarse mesh flux expansion method for the analysis of space-time effects in large LWR cores. Nucl. Sci. and Eng.63 (1977) 437–456Suche in Google Scholar
9 Langenbuch, S.; Maurer, W.; Werner, W.: High-Order schemes for neutron kinetics calculation based on a local polynomial approximation. Nucl. Sci. and Eng.64 (1977) 508–516Suche in Google Scholar
10 CPS Loss of Coolant Accident Analysis (after implementation of 24 cluster control rods at INPP Unit 2). No. TACpd-1245-72257, 2005, Ignalina NPPSuche in Google Scholar
© 2010, Carl Hanser Verlag, München
Artikel in diesem Heft
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Technical Contributions/Fachbeiträge
- Numerical simulation on a HPLWR fuel assembly flow with one revolution of wrapped wire spacers
- Axial-power-shape induced frequency shifts in BWR stability measurements
- Numerical investigation of heat transfer in the vertical annulus between pressure tube and calandria tube of the advanced water cooled reactor
- Uncertainty analysis for fission products transport in CANDU primary heat transport during a severe accident
- Definition of conservative conditions for RIA analysis in the modernized RBMK reactor core
- Assessment of different mechanisms of C-14 production in irradiated graphite of RBMK-1500 reactors
- In-pile measurements of the fission gas pressure and comparison with ROFEM code results
- The time-dependent P1 model for the neutronics of multiplying systems: a review
- Efficiency of reflection coefficients in the isotropic neutron transport equation and computation of the critical-half thicknesses
- Finite differences with exponential filtering in the calculation of reactivity
- Asymptotic solution of critical thickness with direct second kind Chebyshev polynomial approximation in forward and backward scattering
- Interactions of radionuclides in solution with ions and with trace concentrations of solid phase
Artikel in diesem Heft
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Technical Contributions/Fachbeiträge
- Numerical simulation on a HPLWR fuel assembly flow with one revolution of wrapped wire spacers
- Axial-power-shape induced frequency shifts in BWR stability measurements
- Numerical investigation of heat transfer in the vertical annulus between pressure tube and calandria tube of the advanced water cooled reactor
- Uncertainty analysis for fission products transport in CANDU primary heat transport during a severe accident
- Definition of conservative conditions for RIA analysis in the modernized RBMK reactor core
- Assessment of different mechanisms of C-14 production in irradiated graphite of RBMK-1500 reactors
- In-pile measurements of the fission gas pressure and comparison with ROFEM code results
- The time-dependent P1 model for the neutronics of multiplying systems: a review
- Efficiency of reflection coefficients in the isotropic neutron transport equation and computation of the critical-half thicknesses
- Finite differences with exponential filtering in the calculation of reactivity
- Asymptotic solution of critical thickness with direct second kind Chebyshev polynomial approximation in forward and backward scattering
- Interactions of radionuclides in solution with ions and with trace concentrations of solid phase
