Uncertainty and sensitivity analysis of void and power reactivity coefficients in an RBMK-1500 reactor core
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R. Pabarcius
Abstract
Uncertainty and sensitivity analyses were performed for the calculation of power and void reactivity coefficients of an RBMK-1500 reactor core state. Both parameters are important for the reactivity feedback behaviour and are of special safety relevance. The reactivity coefficients were calculated using the 3D-reactor core model QUABOX/CUBBOX-HYCA and the uncertainty and sensitivity analyses were performed by the GRS methodology applying the SUSA software package (Software System for Uncertainty and Sensitivity Analysis). A total number of 20 uncertain input parameters and their probability distributions were identified as possibly relevant for the size of the reactivity effects and taken into account in the SUSA analysis. The method helps to identify the main contributors to the uncertainty of calculated results, as well as to determine two-sided (95 %, 95 %) statistical tolerance intervals of the investigated reactivity coefficients. The approach to quantify uncertain parameters for RBMK-1500 core calculations using the SUSA code package and QUABOX/CUBBOX-HYCA was successfully performed. The results provide guidance where model improvements should be performed to increase the accuracy of the calculations efficiently.
Kurzfassung
Für RBMK-1500 Reaktoren wurden Unsicherheits- und Sensitivitätsanalysen zur Größe des Leistungs- und Voidreaktivitätskoeffizienten durchgeführt. Beide Parameter sind wichtig für das Rückwirkungsverhalten und von besonderer sicherheitstechnischer Bedeutung. Die Reaktivitätskoeffizienten wurden mit dem 3D-Kernmodell QUABOX/CUBBOX-HYCA berechnet, und die Unsicherheits-und Sensitivitätsanalysen wurden nach der GRS-Methodik mit dem Programmpaket SUSA (Software System for Uncertainty and Sensitivity Analysis) durchgeführt. Eine Gesamtzahl von 20 unsicheren Eingabeparametern und ihre Wahrscheinlichkeitsverteilungen wurden als möglicherweise relevant für die Größe der Reaktivitätseffekte bestimmt und in der SUSA-Analyse berücksichtigt. Mit Hilfe dieser Methode können diejenigen Parameter identifiziert werden, die am meisten zur Unsicherheit der berechneten Ergebnisse beitragen, und die beidseitigen statistischen (95 %, 95 %) Toleranzintervalle der untersuchten Reaktivitätskoeffizienten bestimmt werden. Die Vorgehensweise, um unsichere Parameter bei Kernrechnungen mit dem SUSA Programm und QUABOX/CUBBOX-HYCA für RBMK-1500 zu quantifizieren, wurde erfolgreich angewandt. Die Untersuchung zeigt auf, wo durch Modellverbesserungen die Genauigkeit der berechneten Ergebnisse effizient verbessert werden kann.
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© 2005, Carl Hanser Verlag, München
Artikel in diesem Heft
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries/Kurzfassungen
- Editorial
- 70 Volumes Kerntechnik
- Technical Contributions/Fachbeiträge
- Uncertainty and sensitivity analysis of void and power reactivity coefficients in an RBMK-1500 reactor core
- Theoretical studies on thermal stratification in a side heated cavity
- Measurement of the neutron fluence on the spallation source at Dubna
- Neutron reflection and leakage models for one-dimensional reactor computations
- Reactivity worth of the control rods at the ET-RR-2 reactor core
- Neutronic conceptual design of the ETRR-2 cold neutron source
- Criticality analyses of regions containing uranium in the earth history
- Semi-statistical mechanical fuel rod design
- Brennstabauslegung und Brennstabmodellierung – Teil 2
- The chemical separation of Eka-Hg from CERN W targets in view of recent relativistic calculations
- Letter to the Editor
- Comments on the question of the discovery of element 112 as early as 1971
Artikel in diesem Heft
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries/Kurzfassungen
- Editorial
- 70 Volumes Kerntechnik
- Technical Contributions/Fachbeiträge
- Uncertainty and sensitivity analysis of void and power reactivity coefficients in an RBMK-1500 reactor core
- Theoretical studies on thermal stratification in a side heated cavity
- Measurement of the neutron fluence on the spallation source at Dubna
- Neutron reflection and leakage models for one-dimensional reactor computations
- Reactivity worth of the control rods at the ET-RR-2 reactor core
- Neutronic conceptual design of the ETRR-2 cold neutron source
- Criticality analyses of regions containing uranium in the earth history
- Semi-statistical mechanical fuel rod design
- Brennstabauslegung und Brennstabmodellierung – Teil 2
- The chemical separation of Eka-Hg from CERN W targets in view of recent relativistic calculations
- Letter to the Editor
- Comments on the question of the discovery of element 112 as early as 1971
