Critical Power Prediction by CATHARE2 of the OECD/NRC BFBT Benchmark

The main purpose of this study is to evaluate the performance of the French best estimate thermal-hydraulic code CATHARE 2 regarding critical power prediction, comparing the analytical results with the experiments, available in the framework of the International OECD/NRC Benchmark, based on NUPEC (Nuclear Power Engineering Corporation) BWR Full-size Fine-mesh Bundle Tests (BFBT). Two-phase flow calculations and prediction of the void fraction distribution and the critical power were carried out both in steady state and transient cases, using 1D and 3D modeling. Comparison with the test results shows the ability of CATHARE 2 code to predict reasonably the critical power, using appropriate modeling.