Benchmarking of MCNP against B&W LRC Core XI critical experiments

摘要

The MCNP Monte Carlo code and its ENDF/B-V continuous-energy cross- section library previously has been benchmarked against a variety of critical experiments, and that benchmarking recently has been extended to include its ENDF/B-VI continuous-energy cross-section library and additional critical experiments. This study further extends the benchmarking of MCNP and its two continuous-energy libraries to 17 large-scale mockup experiments that closely resemble the core of a pressurized water reactor (PWR). The experiments were performed at Babcock & Wilcox's Lynchburg Research Center in 1970 and 1971. The series was designated as Core XI, and the individual experiments were characterized as different ''loadings.'' The experiments were performed inside a large aluminum tank that contained borated water. The water height for each loading was exactly 145 cm, and the soluble boron concentration in the water was adjusted until the configuration was slightly supercritical, with a value of 1.0007 for k(sub eff). Pin-by-pin power distributions were measured for several of the loadings.