Improvement of Neutronics Calculation Methods for Fast Reactors

To accurately estimate neutronics properties of fast reactors, particularly Japan Sodium-cooled Fast Reactor of 1,500 MW electric, calculational methods are being improved in Japan. This paper describes the planning and the ongoing development of the neutronics calculation methods in the field of 1) assembly calculations including the calculations of effective cross sections, 2) core calculations and 3) uncertainty evaluation and uncertainty reduction.