Authors & Affiliations

Kagramanian V.S., Kriachko M.V.
A.I. Leypunsky Institute for Physics and Power, Obninsk, Russia


In case of nuclear energy system with uranium fuelled light water reactors modeling is sufficient to use one of the indicators for fuel balance: natural uranium consumption or enriched uranium consumption. In case of system with uranium-plutonium fast reactors modeling two approaches are used: balance of whole plutonium mass or fissile plutonium mass, and detailed calculation of isotopic composition on every modeling step. Evaluation of plutonium balance using mass or fissile mass indicator does not allow to take into account different fissile or fertile characteristics of the plutonium isotopes. Detailed calculation allows to take into account plutonium isotopic composition evolution, but requires more computational costs for modeling. Multi-isotopic plutonium equivalenting technique for fast reactor is considered in this paper. For every isotope considered value ratios were calculated based on its contribution to energy production in fast reactor. The reactor fuel indicators evaluation for the different isotopic composition of plutonium in MOX fuel technique is presented. The method of simplified calculation of the isotopic composition of discharged fuel by burnout matrix is presented. For plutonium isotopes considered breeding value ratios were calculated. Plutonium breeding and reactivity change due to burn-up for different isotopic compositions evaluation techniques are presented.

Key words
plutonium, fast reactor, fuel balance, breeding indicators, burnout matrix

Article Text (PDF, in Russan)


UDC 621.039

Problems of Atomic Science and Technology. Series: Nuclear Constants, issue 2:1, 2015