Post test calculations of a severe accident experiment for VVER-440 reactors by the ATHLET code
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H. György
Abstract
Severe accident – if no mitigation action is taken – leads to core melt. An effective severe accident management strategy can be the external reactor pressure vessel cooling for corium localization and stabilization. For some time discussion was going on, whether the in-vessel retention can be applied for the VVER-440 type reactors. It had to be demonstrated that the available space between the reactor vessel and biological protection allows sufficient cooling to keep the melted core in the vessel, without the reactor pressure vessel losing its integrity. In order to demonstrate the feasibility of the concept an experimental facility was realized in Hungary. The facility called Cooling Effectiveness on the Reactor External Surface (CERES) is modeling the vessel external surface and the biological protection of Paks NPP. A model of the CERES facility for the ATHLET TH system code was developed. The results of the ATHLET calculation agree well with the measurements showing that the vessel cooling can be insured for a long time in a VVER-440 reactor.
Kurzfassung
Zur Verhinderung von Kernschmelzen wurde auch bei WWER-440 Reaktoren im Rahmen der Accident Management Strategie das externe Kühlen des Reaktordruckbehälters diskutiert. Damit soll das weitere Ausbreiten des Coriums verhindert werden und eine Stabilisierung des Systems unterstützt werden. Dazu musste gezeigt werden, dass der verfügbare Spalt zwischen Reaktordruckbehälter und biologischem Schild so groß ist, dass darüber eine ausreichende Kühlung möglich ist, die einen Integritätsverlust des Reaktordruckbehälters verhindert und die Schmelze im RDB verbleibt. Dazu wurden Versuche an der Anlage Cooling Effectiveness on the Reactor External Surface (CERES) in Ungarn durchgeführt und mit dem Programm ATHLET nachgerechnet. Die Anlage modelliert die Gegebenheiten des KKW Paks. Sowohl die Experimente als auch die Nachrechnungen zeigen, dass das externe Kühlen auch bei WWER-440 Reaktoren eingesetzt werden kann.
References
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© 2013, Carl Hanser Verlag, München
Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Editorial
- Selected contributions to the XXIInd symposium of the Atomic Energy Research organization
- Technical Contributions/Fachbeiträge
- Fuel cycles of WWER-440: results of basic design modification
- Use of erbium as burnable poison for VVER reactors
- The estimation of the control rods absorber burn-up during the VVER-1000 operation
- The main characteristic of the evolution project SuperVVER with spectrum shift regulation
- Automatic loading pattern optimization tool for Loviisa VVER-440 reactors
- Uncertainties of the neutronic calculations at core level determined by the KARATE code system and the KIKO3D code
- The reactor dynamics code DYN3D and its trigonal-geometry nodal diffusion model
- Comparison of sensitivity and uncertainty in Gd and Er containing fuels for VVER-1000 using TSUNAMI-2D
- Contribution of the number of measured data to calculation uncertainty in the worth of VVER control rods
- A comparison of the FA's models with the detailed and simplified description in the MCU code calculations
- Account for uncertainties of control measurements in the assessment of design margin factors
- Results of precision calculations of three-dimensional power density in VVER-1000 core with feedbacks using MCU code
- CFD analysis of temperature deviations in Gd assembly heads
- Application of statistical uncertainty and sensitivity evaluations to a PWR LBLOCA analysis calculated with the code ATHLET. Part 1: uncertainty analysis
- Post test calculations of a severe accident experiment for VVER-440 reactors by the ATHLET code
- The impact on the competence on severe accidents following the Fukushima event
Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Editorial
- Selected contributions to the XXIInd symposium of the Atomic Energy Research organization
- Technical Contributions/Fachbeiträge
- Fuel cycles of WWER-440: results of basic design modification
- Use of erbium as burnable poison for VVER reactors
- The estimation of the control rods absorber burn-up during the VVER-1000 operation
- The main characteristic of the evolution project SuperVVER with spectrum shift regulation
- Automatic loading pattern optimization tool for Loviisa VVER-440 reactors
- Uncertainties of the neutronic calculations at core level determined by the KARATE code system and the KIKO3D code
- The reactor dynamics code DYN3D and its trigonal-geometry nodal diffusion model
- Comparison of sensitivity and uncertainty in Gd and Er containing fuels for VVER-1000 using TSUNAMI-2D
- Contribution of the number of measured data to calculation uncertainty in the worth of VVER control rods
- A comparison of the FA's models with the detailed and simplified description in the MCU code calculations
- Account for uncertainties of control measurements in the assessment of design margin factors
- Results of precision calculations of three-dimensional power density in VVER-1000 core with feedbacks using MCU code
- CFD analysis of temperature deviations in Gd assembly heads
- Application of statistical uncertainty and sensitivity evaluations to a PWR LBLOCA analysis calculated with the code ATHLET. Part 1: uncertainty analysis
- Post test calculations of a severe accident experiment for VVER-440 reactors by the ATHLET code
- The impact on the competence on severe accidents following the Fukushima event
