Initial implementation of the neutronics codes DRAGON and DONJON at the North-West University

Abstract

The neutronics research group at the North West University plans to use open source neutronics in some of the future research that will be conducted by the group. The open source neutronics codes DRAGON and DONJON were identified as potential options. However, since DRAGON and DONJON were not used in any research conducted at the North West University, the executables of the codes were created using the source codes openly available, and fuel assembly and full core models were developed. These models were based on the North Anna reactor. DRAGON was used in modelling and performing lattice neutronics calculations for the fuel assemblies of the North Anna reactor. DONJON was used in modelling and performing full core calculations for the North Anna reactor. A verification procedure for both the compilation and linking procedure together with the model development was employed. This employed using the models as supplied by the developers and building several intermediate models, which finally led to the North Anna reactor models. The multiplication constant and flux results from the lattice and full core calculations were analysed using known reactor physics principles from literature. It was found that the results were consistent with what can be expected according to the reactor physics principles. Therefore, executable versions of DRAGON and DONJON are obtained for which the source codes are available, and fuel assembly and full core models were developed, suitable as base model candidates for the research plans for the neutronics research group at the North West University. It is noted that a considerable amount of work is still required. This includes the addition of burnable poisons, modelling of control rods, burn-up studies, including spacer grids in the models, and coupling the neutronics results with thermal-hydraulic calculations.