Recent developments in ITEP of new methods and computer codes for nuclear reactor calculations

Recently an advanced method of heterogeneous reactor theory was developed and used for 3D nuclear reactor steady states and space-time calculations. A computer code TRIFON was developed for the solution of space-energy problem and calculation of heterogeneous few-group matrix parameters in a reactor cell. These parameters are used as input data in the computer code SHERATON solving the 3D heterogeneous reactor equation for steady states and in the computer code SHERHAN for 3D space-time neutron processes simulation. Modification of TRIFON was developed for the simulation of space-time processes in subcritical systems with external sources. (author)