Unstructured finite-volume lattice Boltzmann method for the multi-group SP3 simulation

The neutron transport SP3 simulation is a potential technique to realize full-core neutronics calculation, whose unstructured geometry adaptability is very important for flexible and accurate simulation of the advanced reactor. This paper established an unstructured finite-volume lattice Boltzmann method (UFVLBM) for the detailed multi-group neutron transport SP3 simulation on unstructured geometries. The double distribution function based discrete velocity Boltzmann equation (DVBE) is established for solving the SP3 equations, and their equivalence relationship is verified using the Chapman-Enskog expansion. The unstructured finite volume integration is applied to the DVBEs on a cell-centered tessellation to adapt to complicated geometry conditions. The simulation results show that the proposed UFVLBM can be used to solve the multi-group neutron transport SP3 problems accurately and the unstructured geometries can be flexibly adapted. This work may provide some novel ideas for solving the neutron physics simulation on the unstructured complicated geometry. (c) 2022 Published by Elsevier Ltd.