Cálculo de depleção isotópica usando teoria de perturbação generalizada em um sistema subcrítico guiado por uma fonte externa

Abstract

In this thesis, it is proposed and developed a method of isotopic depletion calculation using Generalized Perturbation Theory (GPT), for subcritical systems driven by an external neutron source. Throughout fuel burnup cycle, occur process that cause changes in the nuclide densities and induce variations in the neutron flux, which lead to changes in reaction rates, present in the evolution matrix, in isotopic depletion calculations. The proposed perturbative method treats these reaction rates as integral quantities. And changes in these integral quantities are treated as perturbations coming from the changes in the nuclide densities. This method was applied in a sub-critical reactor driven by an external neutron source whose obtained results show good agreement with those obtained by the direct calculation method. This ensures that the proposed method is a valid alternative to treat problems of this kind.