Methods and computer codes for nuclear systems calculations

Abstract

Some numerical methods for reactor cell, sub-critical systems and 3D models of nuclear reactors are presented. The methods are developed for steady states and spacetime calculations. Computer code TRIFON solves space-energy problem in (X, Y ) systems of finite height and calculates heterogeneous few-group matrix parameters of reactor cells. These parameters are used as input data in the computer code SHERHAN solving the 3D heterogeneous reactor equation for steady states and 3D space-time neutron processes simulation. Modification of TRIFON was developed for the simulation of space-time processes in sub-critical systems with external sources. An option of SHERHAN code for the system with external sources is under development.

On the transmutation of Am in a fast lead-cooled system

“…Fuel cycle length was taken as 5 years as in the standard cycle (at power load factor 0.75) with the burnup of 76, 63 and 46 MWd/kg for three zones of reactor core with total loading of 16.2 t of heavy atoms. The simulation of fuel cycles was performed by TRIFON code [2] until almost an equilibrium mode of operation was reached. It was supposed that a part of Pu was used in the next cycle, the burnt americium was added (from the spent fuel of LWR) and Cm was sent to a storage to decay into 239 Pu and 240 Pu.…”