Benchmark on the Venus-2 MOX core measurements

In the framework of joint activities carried out by the OECD/NEA Working Party on the Physics of Plutonium Fuels and Innovative Fuel Cycles (WPPR) and the Task Force on Reactor-based Plutonium Disposition (TFRPD), a blind international benchmark exercise for the prediction of power distribution in the two-dimensional VENUS-2 MOX core experiment was launched in May 1999. The aim of this exercise was to investigate the predictive capability of the current production codes with the latest nuclear data libraries used for calculating MOX-fuelled systems. Twelve participants from ten countries participated in this first international experiment-based benchmark. This report provides details of the comparative analysis between calculated and measured results. Comparison with experimental results identified the origins of discrepancies between calculations and measurements and enabled the quantitative comparison of the relative merits of the different.calculation methods. As the benchmark was two-dimensional, a benchmark based on three dimensional VENUS-2 experimental results will be launched for a more thorough investigation into the calculation methods used for MOX-fuelled systems. (author)