Studies were made on theoretical and practical application of the finite element method to the neutron transport equation. Studies were also conducted on various numerical methods and physical models on nuetronic diffusion. The following information may be useful for your research
Neutronics Modeling of the High Flux Isotope Reactor using COMSOL
David Chandler, G. Ivan Maldonado, R. T. Primm and J. D. Freels.