486. 高速増殖炉におけるTh-U-Pu系のサイクル,(I)

抄録

Recycling patterns and the long-time behavior of Th-U-Pu fast breeders have been investigated. The basic cycle adopted was to charge fertile materials (²³²Th, ²³⁸U) into both core and blanket, to sell a portion γ_B of the fissile materials (²³³U, ²³⁹Pu) formed in the blanket, and to recharge the remaining 1-γ_B into core. Of the fuel produced fuel in the core a part γ_C is sold in the market.
In this fuel cycle, γ_B and γ_C are either time dependent variables or else constant, so that four alternative recycling patterns were considered with different combinations of these factors. To facilitate the procedures of refabrication and estimation of Doppler effect, the system is controlled in such manner as to let the charging ratio into core and the composition ratio of ²³²Th and ²³⁸U in blanket be both constant.
The burnup equations for these recycling patterns have been derived as linear and non-linear differential equations. Breeding rates can be determined by solving the eigenvalue problems of these burnup equations.