Parameter studies for fast reactors on nuclear equilibrium state

A parametric study is performed for a fast reactor in the equilibrium state, (where the concept of loading natural uranium and confining actinides is proposed), with changing fuel types or coolant materials. In this study, an Equilibrium Cell Iterative Calculation System (ECICS) is employed, in which and equilibrium nuclide density calculation is combined with a cell neutron transport calculation. The oxide, nitride and metallic fuel types and the sodium, sodium-potassium, lead and lead-bismuth coolant materials are considered for the parametric study and the criticality performance for each reactor type in the equilibrium state is investigated. (author)