Summary of Results for the VENUS-7 Benchmark

摘要

Within the OECD/NEA Working Party on Scientific Issues in Reactor Systems, an international benchmark was specified concerning the VENUS-7 critical assemblies as part of a continuous LWR criticality and reactor physics benchmark activity, with the focus on MOX and mixed UO2/MOX-cores. This contribution summarizes the results. In pin cell calculations, excellent agreement is obtained among all benchmark contributions. Concerning the critical assemblies, the agreement among the calculated multiplication factors is also very satisfactory, accepting a considerable underestimation of the experimental values by all calculations. The degree of underestimation in Monte Carlo solutions using continuous energy nuclear data is directly related to the basic data used. Calculations with ENDF/B-VI yield the lowest multiplication factors, while using JEFF-3.1 yields the highest values. This is in line with the results for other small LWR critical assemblies. The quality of multiplication factors and reactivity differences obtained with codes using multi-group data is comparable to Monte Carlo results.