New articles published: V. 14 n. 1 (2026)

Advances of the Modified Spectral Deterministic method applied in the solution of two-dimensional neutron shielding problems considering linearly anisotropic scattering

Abstract: This work extends the application of the spectral-nodal method SDM, cf., Modified Spectral Deterministics (MSD-CN), to solve neutron shielding problems (fixed-source) in two-dimensional Cartesian rectangular geometry, considering problems with linearly anisotropic scattering in the formulation of discrete ordinates ( ), using a constant approximation for the transverse neutron leakage terms. The essence of this methodology lies in the use of the intranodal analytical solution of the neutron transport equation and an iterative process that employs the concept of spatial sweeping, like the Source Iteration method used in the fine-mesh method DD, cf., Diamond Difference, for estimating the angular neutron fluxes emerging in the spatial nodes. To validate the methodology, a numerical simulation of two model-problems was performed, where the MSD-CN was able to achieve numerical results with a small relative deviation compared to the reference method Diamond Difference alongside a performance test to compute the execution time of the algorithm. All methods were implemented in the computational language C++. Read full article.