ZPPR-21 Critical Benchmark Analyses with ENDF/B-V and -VII Data

摘要

The six benchmark problems for the ZPPR-21 critical experiments phases A through F were analyzed using the ENDF/B-V.2 and ENDF/B-VII.0 data. For reference calculations, Monte Carlo simulations were performed using the VIM code with the continuous energy cross sections. For deterministic calculations, composition and region dependent multi-group cross sections were generated using the ET0E-2/MC~2-2/SDX code system and core calculations were performed with the TWODANT discrete ordinate transport code. Based on sensitivity studies, deterministic core calculations were carried out with 230 energy groups, ～1 cm spatial mesh size, S_(24) angular approximation, and P_5 anisotropic scattering order. Comparisons showed that the core multiplication factor determined with TWODANT agreed well with the VIM Monte Carlo solution within 0.20 %△k for the ENDF/B-V.2 data and 0.27 %△k for the ENDF/B-VII.0 data. Detailed comparisons of reaction rates were also made between VIM and TWODANT solutions. The results showed that the multigroup cross sections generated with MC~2-2 accurately reproduced the isotopic reaction rates of VIM calculations.