Reactivity Initiated Accident Benchmark Phase III Report


Following the recommendations from the technical workshop on “Nuclear Fuel Behaviour during Reactivity-Initiated Accidents” organised by the Nuclear Energy Agency (NEA) in September 2009, a first benchmark of the RIA fuel codes was organised between 2010 and 2013. A second phase of the benchmark was launched in 2014, and the reports resulting from these activities were approved by the Committee on the Safety of Nuclear Installations in 2015 and 2016.

One recommendation from Phase II of the benchmark was to launch a complementary phase focused on uncertainty and sensitivity analyses on an irradiated case in order to identify the corresponding influential input parameters. In particular, the impact of the initial state and key models on the results of the transient needed to be investigated and a sensitivity study needed to be performed in order to identify or confirm the most influential input uncertainties.

This report presents the conclusions from the uncertainty analysis and recommendations for future work.