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Sugino, Kazuteru; Takino, Kazuo
JAEA-Data/Code 2019-011, 110 Pages, 2020/01
JAEA-Data-Code-2019-011.pdf:3.37MB
A deterministic discrete ordinates method (SN method) transport calculation code for three-dimensional hexagonal geometry has been developed as the MINISTRI code (Ver. 7.0). MINISTRI is based on the triangle-mesh finite difference method, which can perform neutron transport calculations with high accuracy for cores of fast power reactors and assemblies of the Russian BFS critical facility. The present study has derived a proper scheme for remarkably improving the convergence of MINISTRI by investigating the issue of previous MINISTRI (Ver. 1.1), which sometimes plays a poor convergence performance in calculations for large-scale power reactor cores. The verification test of improved MINISTRI has been carried out for various cores by setting the reference result as the multi-group Monte-Carlo calculation with the same cross-sections as used in MINISTRI. As a result, it is found that the agreements are within 0.1% for eigenvalues and within 0.7% for power distributions. Thus, the satisfying accuracy of MINISTRI has been confirmed. In order to reduce the calculation time, the initial diffusion calculation scheme and the parallel processing have been implemented. As a result, the calculation time is reduced to the approximately one tenth compared with previous MINISTRI. Furthermore, adoption of the treatment of the anisotropic cell streaming effect, preparation of the perturbation calculation tool, implementation of the function for specification of the triangle-mesh-wise material and merging of the hexagonal-mesh calculation code MINIHEX have been carried out. Thus, the versatility of MINISTRI has been enhanced.
Nagaya, Yasunobu; Mori, Takamasa
Journal of Nuclear Science and Technology, 42(5), p.428 - 441, 2005/05
Times Cited Count：76 Percentile：96.82(Nuclear Science & Technology)A new method to estimate a change in the effective multiplication factor due to the perturbed fission source distribution has been proposed for Monte Carlo perturbation calculations with the correlated sampling and differential operator sampling techniques. The method has been implemented into the MVP code for verification. Simple benchmark problems have been set up for fast and thermal systems and the applicability of the method has been verified with the problems. In consequence, it has been confirmed that the method is very effective to estimate the change. It has been also shown that there are some cases where the perturbed source effect is significant and the change in reactivity cannot be estimated accurately without taking the effect into account. Even in such cases, the new method can estimate the perturbed source effect and the estimation of the change in reactivity has been remarkably improved.
C and Pu sample worths in FCA assembly XVII-1Nagaya, Yasunobu; Ono, Akio; Osugi, Toshitaka
JAERI-Research 95-003, 40 Pages, 1995/01
JAERI-Research-95-003.pdf:1.37MB
no abstracts in English
; Iijima, Tsutomu
Journal of Nuclear Science and Technology, 14(6), p.462 - 464, 1977/06
Times Cited Count：3no abstracts in English
Nuclear Science and Engineering, 51(2), p.180 - 188, 1973/02
Times Cited Count：27no abstracts in English
