Advanced Alternatives of VVER-440 Fuel Assembly

The main goals of fuel development for pressurized water reactor are effectiveness and economic efficiency. Both requirements can be achieved by gradual increase of discharged fuel burn-up and prolongation of fuel cycle. The mentioned effects can be reached by optimisation of fuel assembly profiling, fuel enrichment raise, and by parasitic absorption reduction. These methods were used in VVER-440 fuel assembly optimisation, described in this paper. Fuel pin configurations with enrichment limit 5 % and also enlarged one up to 5.95 % U²³⁵ were designed. Reduction of parasitic absorption was limited by carcass frame of the assembly. Basic characteristics of the best assembly proposals are presented and effects on equilibrium fuel cycle of VVER-440 reactor are characterized.