Results of the QUENCH-16 Bundle Experiment on Air Ingress (KIT Scientific Reports ; 7634)

The out-of-pile bundle experiment QUENCH-16 on air ingress was conducted in the electrically heated 21-rod QUENCH facility at KIT in July 2011. The oxidation of the Zircaloy-4 claddings in air following a limited pre-oxidation in steam was examined. Three contributors for intensive hydrogen production during the final reflood were identified: 1) re-oxidation of nitrides, 2) secondary oxidation of cladding metal by steam penetrated through the porous re-oxidized scales and 3) melt oxidation

Final report on rod cladding failure during SGTR

Achievements on modelling fission product release from defective rods during a steam generator tube rupture transient and iodine spiking have been obtained and presented in this deliverable

Third Yearly Activity Report

The calculation work performed during the 3rd project year in WP2 as well as the R&D activities carried out in WP3, WP4 and WP5 are described in this report. In addition, the work dedicated to the project management (WP1) as well as to WP6 regarding the dissemination/communication activities and the education/training program (e.g. the follow-up of the mobility program between different organizations in the consortium, training on simulation tools and activities accomplished by PhD/post-doctoral students) is also reported

Impact of thermal and chemical treatment on the mechanical properties of E110 and E110G cladding tubes

The mechanical and corrosion behavior of the Russian zirconium fuel cladding alloy E110, predominantly used in VVERs, has been investigated for many decades. The recent commercialization of a new, optimized E110 alloy, produced on a sponge zirconium basis, gave the opportunity to compare the mechanical properties of the old and the new E110 fuel claddings.Axial and tangential tensile test experiments were performed with samples from both claddings in the MTA EK. Due to the anisotropy of the cladding tubes, the axial tensile strength was 10–15% higher than the tangential (measured by ring tensile tests). The tensile strength of the new E110G alloy was 11% higher than that of the E110 cladding at room temperature.Some samples underwent chemical treatment – slight oxidation in steam or hydrogenation – or heat treatment – in argon atmosphere at temperatures between 600 and 1000 °C. The heat treatment during the oxidation had more significant effect on the tensile strength of the claddings than the oxidation itself, which lowered the tensile strength as the thickness of the metal decreased. The hydrogenation of the cladding samples slightly lowered the tensile strength and the samples but they remained ductile even at room temperature. Keywords: E110, E110G, Tensile test, Tensile strength, Heat treatment, Oxidation, Hydrogenatio

The Application of the TRANSURANUS Fuel Performance Code to WWER Fuel: An Overview

The present review paper outlines the collaborative efforts for the establishment of the TRANSURANUS version for the simulation of VVER fuel pin behavior, which has been presented at this series of international conferences organized by the INRNE since 1994. The paper therefore starts with very briefly reviewing the development of the TRANSURANUS fuel performance code in collaboration with various organizations from EU member states operating VVER reactors. The development started with the application to normal operating conditions in the frame of different bilateral agreements supported by the European Commission and the IAEA (e.g. PHARE and PECO projects), followed by the specific project dedicated to its application to the loss of coolant type accidents (EXTRA). In the second part of the paper, a summary will be given of the verification, validation and benchmarking efforts, on the basis of the experimental data included in the IFPE database of the NEA, as well as in the frame of the co-ordinated research projects of the IAEA (e.g. FUMEX, FUMAC), and most recently also the Euratom project ESSANUF co-ordinated by Westinghouse Electric Sweden. Finally, we will outline the current plans for further improving the simulation capabilities of VVER fuels by means of TRANSURANUS