Development and verification of a software system for the probabilistic safety analysis of nuclear plants as part of the proryv project

Probabilistic safety analysis (PSA) normally requires the development of a sophisticated computer model of the nuclear plant with a comprehensive reliability and safety study based on respective software. In 2013–2015, CRISS 5.3, a PSA software system, was developed and verified by Afrikantov OKBM as part of the effort, entitled New Generation Codes, under the Proryv (Breakthrough) project. The paper presents a review of the software tools used in the industry for the PSA of nuclear units and analyzes the capabilities of these tools. It also describes in brief the CRISS 5.3 software system intended to model and analyze safety systems and the nuclear plant as the whole as part of probabilistic safety analyses at all nuclear plant lifecycle stages. The paper presents results of the CRISS 5.3 code verification through the comparison of the analysis results obtained using the CRISS 5.3 system against analytical formulas and results of a qualitative and quantitative analysis based on certified nuclear plant PSA software tools.