Study on methodology to estimate isotope generation and depletion for core design of HTGR

Fukaya, Yuji   ; Ueta, Shohei   ; Goto, Minoru  ; Shimakawa, Satoshi

An investigation on methodology to estimate isotope generation and depletion had been performed in order to improve the accuracy for HTGR core design. Solving the burn-up equations, generating effective cross section and employing nuclide data are the technical problems. Especially for the generating effective cross section, the core burn-up calculation has a technological problem in common with point burn-up calculation. Thus, the investigation had also been performed for the core burn-up calculation to develop new code system in the future. As a result, it was found that the cross section with the extended 108 energy groups structure from the SRAC 107 groups structure to 20 MeV and the cross section collapse using the flux obtained by the deterministic code SRAC is proper for the use. In addition, an investigation on the preparation condition for nuclear data for a safety analysis and a fuel design was also performed. As a result, the needs for the nuclear data ware made clear.