Application of statistical uncertainty and sensitivity evaluations to a PWR LBLOCA analysis calculated with the code ATHLET. Part 1: uncertainty analysis
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Y. Kozmenkov
Abstract
Usually, reactor safety analyses are based on the traditional conservative deterministic approach. An alternative approach to reactor safety analyses uses best estimate computer codes in combination with quantification of uncertainties in model and plant parameters. The German Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) has applied the methodology of uncertainty analysis based on the Wilks’ approach. According to this approach, the number of calculations required to perform a probabilistic estimation of an output parameter with a given coverage/confidence level (e.g., 95%/95%) does not depend on the number of input uncertainty parameters. In this paper, the results of an uncertainty analysis for a Large Break LOCA scenario for a generic German PWR of the Konvoi design are reported. All calculations were performed using the system code ATHLET Mod 2.2 Cycle A. The EXCEL-integrated software SUSA developed by GRS was used for generation of the uncertainty parameter vectors, their incorporation into ATHLET input files and for statistical evaluation of the results.
Kurzfassung
Üblicherweise basieren Reaktorsicherheitsanalysen auf der konservativ-deterministsichen Herangehensweise. Ein alternativer Weg besteht in einer best-estimate-Simulation in Kombination mit der Quantifizierung von Unsicherheiten in den Ergebnissen, die durch Unsicherheiten in Modellparametern und Randbedingungen bedingt sind. Die Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) hat eine Methodik für Unsicherheitsanalysen entwickelt und angewandt, die auf der Theorie von Wilks beruht. Danach hängt die Anzahl der Störfallrechnungen, die erforderlich ist, um einen Zielparameter mit einer bestimmten statistischen Abdeckung und einem Vertrauensgrad (z.B. 95%/95%) probabilistisch zu ermitteln, nicht von der Anzahl der unsicheren Parameter ab. In diesem Beitrag werden die Ergebnisse einer Unsicherheitsanalyse für ein Störfallszenarium mit großem Leck für einen generischen DWR Konvoi vorgestellt. Die Störfallrechnungen wurden mit dem Systemcode ATHLET Mod 2.2 Cycle A ausgeführt. Die EXCEL-basierte Software SUSA der GRS wurde für die Generierung der Vektoren unsicherer Parameter, ihre Integration in den Eingabedatensatz von ATHLET und die statistische Auswertung benutzt.
References
1 Martin, R. P.; O'Dell, L. D.: AREVA's realistic large break LOCA analysis methodology. Nuclear Engineering and Design235 (2005) 1713–1725Suche in Google Scholar
2 Glaeser, H.: GRS Method for Uncertainty and Sensitivity Evaluation of Code Results and Applications. Science and Technology of Nuclear Installations, Volume 2008, Article ID 79890110.1155/2008/798901Suche in Google Scholar
3 Wilks, S. S.: Determination of Sample Sizes for Setting Tolerance Limits. Ann. Math. Stat.12 (1941) 91–96Suche in Google Scholar
4 Kloos, M.; Hofer, E.: SUSA Version 3.5. The PC Version of the Software System for Uncertainty and Sensitivity Analysis of Results from Computer Models. User's Guide and Tutorial. GRS, February 2002Suche in Google Scholar
5 AustregesiloH.; et. al.: ATHLET Mod 2.2 Cycle A. Models and Methods. GRS-P-1/Vol. 4, Rev. 2, July 2009Suche in Google Scholar
6 AustregesiloH.; et. al.: ATHLET Mod 2.2 Cycle A. Input Data Description. GRS-P-1/Vol. 1, Rev. 5, July 2009Suche in Google Scholar
7 Glaeser, H.; et. al.: Methodenentwicklung und exemplarische Anwendungen Bestimmung der Aussagesicherheit von Rechenprogrammergebnissen. Abschlußbericht GRS-A-3443, November 2008Suche in Google Scholar
8 Biasi, L.; et. al.: Studies on burnout, Part 3 – A new correlation for round ducts uniform heating and its comparison with world data. Energia Nucleare14 (1967)Suche in Google Scholar
9 Geelhood, K. J.; et.al.: Predictive Bias and Sensitivity in NRC Fuel Performance Codes. NUREG/CR-7001, PNNL-17644, U.S. NRC, October 2009, pp. 2.9, 2.11–2.12Suche in Google Scholar
10 Sunderland, D.: (ANATECH Corp.), Reflections on 25 years of LWR fuel modeling, challenges and contemporary issues. A Presentation to the Nuclear Science and Technology Interaction Program (NSTIP), Oak Ridge National Laboratory, July 8, 2011Suche in Google Scholar
11 ArtemovaL.M.; et. al.: Sensitivity analysis and verification of fuel rod model used in coupled neutronic and thermal-hydraulic codes, 17th AER Symposium on VVER Reactor Physics and Reactor Safety, 23–29 September 2007, Crimea, UkraineSuche in Google Scholar
12 Seeberger, G.-J.; Trewin, R.; Zeisler, L.-P.: From phenomena to acceptance criteria. A statistical LBLOCA analysis, Jahrestagung Kerntechnik, Berlin, 17–19 May 2011Suche in Google Scholar
13 Popov, S. G.; et. al.: Thermophysical properties of MOX and UO2 fuels the effects of irradiation. ORNL/TM-2000/351, July 2000Suche in Google Scholar
© 2013, Carl Hanser Verlag, München
Artikel in diesem Heft
- 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
Artikel in diesem Heft
- 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
