Comparison of Serpent and HELIOS-2 as applied for the PWR few-group cross section generation

This paper discusses recent modifications to the Serpent Monte Carlo code methodology and related to the calculation of few-group diffusion coefficients and reflector discontinuity factors. The new methods were assessed in the following manner. First, few-group homogenized cross sections calculated by Serpent for a reference PWR core were compared with those generated by commercial deterministic lattice transport code HELIOS-2. Second, Serpent and HELIOS-2 few-group cross section sets were later employed by nodal diffusion code DYN3D for the modeling of the reference PWR core. Finally, the nodal diffusion results obtained using the both cross section sets were compared with the full core Serpent Monte Carlo solution. The test calculations show that Serpent can calculate the parameters required for nodal analyses similar to conventional deterministic lattice codes.