Method for Condensation of the Macroscopic Transport Cross-Sections for Few-Group Criticality Analyses of FBR MONJU by the Code NSHEX

TODOROVA, Galina*; Nishi, Hiroshi*; Ishibashi, Junichi;

Journal of Nuclear Science and Technology, 41(12), p.1237 - 1244, 2004/12

https://doi.org/10.1080/18811248.2004.9726353

In order to reduce the ezisting energy-group collapsing effect in the few-group results for the effective multiplication factor; a new algorithm for condensation of the macroscopic transport XS has been proposed and verified. This work presents the definition of the new collapsing algorithm, the results from the verification tests and a short discussion from the viewpoint of the consistency of the algorithm with the specific finite-difference method of the code NSHEX. According ti the presented results, the new collapsing algorithm can be recommended for condensation of the transport XS from 70 into few enerfy-group structures.