부산대학교 도서관

We have developed a three-dimensional (3-D) model of a BWR to determine the radiation fields (neutron and gamma) throughout the core shroud in order to investigate the role of irradiation on the observed cracks. To handle large computational requirements, we have used the PENTRAN™ (Parallel Environment Neutral-particle TRANsport) 3-D, parallel SN code. Coupled neutron and gamma (67-group) calculations have been performed using S8 level symmetric quadrature set and BUGLE-96 cross-section library with P3 anisotropic scattering order. We have compared 3-D results with two-dimensional (2-D) results and concluded that 3-D calculations are necessary. In order to verify the 3-D multigroup PENTRAN™ results, we have performed 3-D multigroup TORT and continuous-energy A3MCNP™ (Automated Adjoint Accelerated MCNP) calculations and have obtained very good agreement. Timing studies have demonstrated that PENTRAN™ is highly scalable (∼90%).