CASMO5 ANALYSIS OF NCA TUNGSTEN CRITICAL EXPERIMENTS

摘要

This analysis of a series of critical experiments demonstrates the accuracy of CASMO5's predicted fission rate distributions in the presence of tungsten gray control rods, which are inserted during operation of the AP1000 PWR. The RMS error of the computed fission rate range between 0.007 and 0.014 over the five core configurations, with a maximum absolute difference of 0.025. This compares favorably with the quoted 2% standard deviation in the measurements. Comparison of identical 2D CASMO5 and MCNP6 models of the cores reveals excellent agreement for the core multiplication factors, within 100 pcm when using CASMO5's 586 energy group structure.