Analytical assessment for stress corrosion fatigue of CANDU fuel elements under load following conditions
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G. Horhoianu
Abstract
When nuclear power reactors are operated in a load following (LF) mode, the nuclear fuel may be subjected to step changes in power on weekly, daily, or even hourly basis, depending on the grid's needs. Two load following tests performed in TRIGA Research Reactor of Institute for Nuclear Research (INR) Pitesti were simulated with finite elements computer codes in order to evaluate Stress Corrosion Fatigue (SCF) of the sheath arising from expansion and contraction of the pellets in the corrosive environment. The 3D finite element analyses show that the cyclic strains give highly multiaxial stresses in the sheath at ridge region. This paper summarizes the results of the analytical assessment for SCF and their relation to CANDU fuel performance in LF tests conditions.
Kurzfassung
Beim Lastfolgebetrieb (LF) von Kernkraftwerken kann sich die Leistung des Kernbrennstoffs wöchentlich, täglich oder sogar stündlich ändern, in Abhängigkeit des Netzbedarfs. Zwei Beladungstests wurden am TRIGA Forschungsreaktor des Institute for Nuclear Research (INR) Pitesti durchgeführt mit Rechencodes auf der Basis finiter Elemente um so Spannungskorrosionsermüdung (SCF) der Ummantelung aufgrund der Expansion und der Kontraktion der Pellets in korrosiver Umgebung zu untersuchen. Die 3D Finite-Elemente-Analyse zeigt, dass sich durch wiederholte Beanspruchung hohe multiaxiale Spannungen in der Ummantelung ergeben. Dieser Beitrag fasst die Ergebnisse der analytischen Bestimmung der SCF und ihr Einfluss auf die Leistungsfähigkeit von CANDU Brennelementen unter LF Testbedingungen zusammen.
References
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© 2012, Carl Hanser Verlag, München
Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Technical Contributions/Fachbeiträge
- Analytical assessment for stress corrosion fatigue of CANDU fuel elements under load following conditions
- Development of a thermal-hydraulic analysis code for annular fuel assemblies
- Reduction of fluid property errors of various thermohydraulic codes for supercritical water systems
- Computational fluid dynamics validation study of steam condensation on the containment walls
- CFD analysis of a hydraulic valve for cavitating flow
- Thermal plume behaviour in the Kadra reservoir at Kaiga atomic power station – Part 2: studies for the case of four and six units in operation
- 124I production for PET imaging at a cyclotron
- Investigation of ground state features of some medical radionuclides
- Solution of the radiative transfer equation with the successive order scattering transport approximation and its application to a biological medium
- Solving the constant source problem for the quadratic anisotropic scattering kernel using the modified FN method
- Application of the Laplace transform method for computational modelling of radioactive decay series
- A standing wave reactor by continuous radial fuel shuffling
- Technical Notes/Technische Mitteilungen
- On the radial flux shape of a fast standing wave reactor operated by radial fuel shuffling
Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Technical Contributions/Fachbeiträge
- Analytical assessment for stress corrosion fatigue of CANDU fuel elements under load following conditions
- Development of a thermal-hydraulic analysis code for annular fuel assemblies
- Reduction of fluid property errors of various thermohydraulic codes for supercritical water systems
- Computational fluid dynamics validation study of steam condensation on the containment walls
- CFD analysis of a hydraulic valve for cavitating flow
- Thermal plume behaviour in the Kadra reservoir at Kaiga atomic power station – Part 2: studies for the case of four and six units in operation
- 124I production for PET imaging at a cyclotron
- Investigation of ground state features of some medical radionuclides
- Solution of the radiative transfer equation with the successive order scattering transport approximation and its application to a biological medium
- Solving the constant source problem for the quadratic anisotropic scattering kernel using the modified FN method
- Application of the Laplace transform method for computational modelling of radioactive decay series
- A standing wave reactor by continuous radial fuel shuffling
- Technical Notes/Technische Mitteilungen
- On the radial flux shape of a fast standing wave reactor operated by radial fuel shuffling
