THE S$sub 4$ AND FEW-GROUP DIFFUSION CALCULATIONS OF FAST REACTORS

Journal Article · Mon Jul 01 04:00:00 EDT 1963 · Mem. Fac. Eng. Kyoto Univ.

OSTI ID:4049305

Ota, M; Nishihara, H

To eliminate a large amount of numerical work in the calculation of fast breeders, the possibility that few-group diffusion theory might give acceptable results in some cases was investigated. A hypothetical /sup 233/U--/sup 232/Th system with large core size ( approximates 670 l) and a hypothetical /sup 239/Pu-- /sup 238/U fast reactor with small core size ( approximates 50 l) are adopted. These systems are assumed to be of spherically symmetric geometry. One- dimensional calculations are applied to obtain the static characteristics of the systems. The results from few-group S/sub 4/ and diffusion methods seem to indicate that 4- or 3-group diffusion calculations might be used in place of 3- group S/sub 4/ computations for both large and small fast reactors. A new convergence criterion imposed upon the static parameters is proposed. The leakage rate of neutrons from the blanket is selected as the sensitive measure of convergence. This rate is estimated in 2 ways, with the aid of neutron current and by neutron inventory. A sufficiently converged state is reached when these 2 values coincide. The necessary number of spatial mesh points may also be inferred by comparing these 2 values. (from NSA of Japan)

• Research Organization: Kyoto Univ.
• NSA Number: NSA-18-019275
• OSTI ID: 4049305
• Journal Information: Mem. Fac. Eng. Kyoto Univ., Journal Name: Mem. Fac. Eng. Kyoto Univ. Vol. Vol: 25
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BLANKETS
BREEDING
DIFFUSION
FAST NEUTRONS
GROUP THEORY
LOSSES
MATHEMATICS
NEUTRONS
PLUTONIUM 239
REACTOR CORE
REACTOR TECHNOLOGY
REACTORS
SPHERES
THORIUM 232
URANIUM 233
URANIUM 238
VOLUME