Implementation of measures to ensure hydrogen explosion safety in case of severe accidents for NPP-2006 projects designed by «Atomproekt»

The relevance of this study stems from the need to find new solutions to improve the safety of large-capacity nuclear power plants with passive safety systems. In case of beyond design basis accidents with severe core damage, hydrogen resulting from the high-temperature interaction of steam with zirconium alloy fuel rod cladding, mixed with air and steam, can form an explosive atmosphere that threatens containment integrity and the release of radioactive substances into the environment. To prevent such phenomena, nuclear power plants use various control measures and technical means aimed at preventing the formation of explosive hydrogen-containing mixtures. This study presents methodological approaches to ensuring hydrogen explosion safety and provides results of justifying the effectiveness of control measures implemented in various NPP-2006 designs of Atomproekt JSC.

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