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DOE OSTI · 1169248

Risk-Informed Safety Margin Characterization Methods Development Work

Smith, Curtis L·Ma, Zhegang·Riley, Tom·Mandelli, Diego·Nielsen, Joseph W·Alfonsi, Andrea·Rabiti, Cristian
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Abstract

This report summarizes the research activity developed during the Fiscal year 2014 within the Risk Informed Safety Margin and Characterization (RISMC) pathway within the Light Water Reactor Sustainability (LWRS) campaign. This research activity is complementary to the one presented in the INL/EXT-??? report which shows advances Probabilistic Risk Assessment Analysis using RAVEN and RELAP-7 in conjunction to novel flooding simulation tools. Here we present several analyses that prove the values of the RISMC approach in order to assess risk associated to nuclear power plants (NPPs). We focus on simulation based PRA which, in contrast to classical PRA, heavily employs system simulator codes. Firstly we compare, these two types of analyses, classical and RISMC, for a Boiling water reactor (BWR) station black out (SBO) initiating event. Secondly we present an extended BWR SBO analysis using RAVEN and RELAP-5 which address the comments and suggestions received about he original analysis presented in INL/EXT-???. This time we focus more on the stochastic analysis such probability of core damage and on the determination of the most risk-relevant factors. We also show some preliminary results regarding the comparison between RELAP5-3D and the new code RELAP-7 for a simplified Pressurized Water Reactors system. Lastly we present some conceptual ideas regarding the possibility to extended the RISMC capabilities from an off-line tool (i.e., as PRA analysis tool) to an online-tool. In this new configuration, RISMC capabilities can be used to assist and inform reactor operator during real accident scenarios.

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97 MATHEMATICS AND COMPUTINGBWRDynamic PRAPRARELAPsafety marginSBO

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Smith, Curtis L, Ma, Zhegang, Riley, Tom, Mandelli, Diego, Nielsen, Joseph W, Alfonsi, Andrea, Rabiti, Cristian. 2014-09-01. Risk-Informed Safety Margin Characterization Methods Development Work. https://doi.org/10.2172/1169248

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