Validation of burnup calculation code SWAT4 by evaluation of isotopic composition data of mixed oxide fuel irradiated in pressurized water reactor

Kashima, Takao; Suyama, Kenya; Mochizuki, Hiroki*

Energy Procedia, 71, p.159 - 167, 2015/05

https://doi.org/10.1016/j.egypro.2014.11.866

The nuclear fuel cycle program of Japan would be delayed because of the impact of the Fukushima Daiichi NPP accident in 2011. Excessive plutonium, however, has to be utilized as mixed-oxide (MOX) fuel to reduce the quantity of plutonium possessed by Japan. Calculation codes and libraries adopted in the fuel cycle analyses of MOX fuel should be benchmarked based on comparison between calculation results and experimental data. From another viewpoint, nuclide inventory analyses of MOX fuel is important for evaluations of the Fukushima accident because MOX fuel has been loaded in the Unit 3 reactor. ARIANE is a PIE program which includes measurements of nuclide compositions of spent MOX fuels discharged from both of pressurized and boiling water reactors. In this study, the PIE data of MOX fuels irradiated in a pressurized water reactor were analyzed by the integrated burnup code system SWAT4 that combines the point burnup system ORIGEN2 and neutron transport calculation solvers, the continuous energy Monte Carlo code MVP or MCNP, and the deterministic neutronics calculation code SRAC. The calculation results of SWAT4 have generally same trends with the case of UO fuel analyses. For major uranium and plutonium isotopes, deviations less than 5% were obtained. This means that SWAT4 has the same accuracy to predict isotopic compositions of irradiated MOX fuel with the case of UO fuel. The radial distribution of isotopes in a pellet was also analyzed, whose results were compared with that measured by SIMS. SWAT4 predicted well the isotope and burnup distributions in an irradiated MOX pellet.

Corrections to the Nd method of evaluation of burnup for the PIE samples from Mihama-3 and Genkai-1 reactors

Suyama, Kenya; Mochizuki, Hiroki*

Annals of Nuclear Energy, 33(4), p.335 - 342, 2006/03

https://doi.org/10.1016/j.anucene.2005.11.009

The value of the burnup is one of the most important parameters of samples taken by post irradiation examination (PIE). In this study, concerning the PIE data from Mihama-3 and Genkai-1 PWRs, which were taken at the Japan Atomic Energy Research Institute, the burnup values of the PIE samples were re-evaluated and the PIE data are re-analyzed using SWAT and SWAT2 code systems with JENDL-3.3 library. This analysis concludes that the burnup values of samples from Mihama-3 and Genkai-1 PWRs should be corrected of 2-3%. The effect of re-evaluation of the burnup value on the neutron multiplication factor is approximately 1% for PIE samples having the burnup of larger than 30 GWd/t. Comparison between calculation results using a single pin cell model and an assembly model is carried out. Because the both results agreed within a few percents, we concluded that the single pin cell model is suitable for the analysis of PIE samples and the underestimation of plutonium isotopes does not result from the geometry model.

Validation of integrated burnup code system SWAT2 by the analyses of isotopic composition of spent nuclear fuel

Suyama, Kenya; Mochizuki, Hiroki*; Okuno, Hiroshi; Miyoshi, Yoshinori

Proceedings of International Conference on Physics of Fuel Cycles and Advanced Nuclear Systems; Global Developments (PHYSOR 2004) (CD-ROM), 10 Pages, 2004/04

This paper provides validation results of SWAT2, the revised version of SWAT, which is a code system combining point burnup code ORIGEN2 and continuous energy Monte Carlo code MVP, by the analysis of post irradiation examinations (PIEs). Some isotopes show differences of calculation results between SWAT and SWAT2. However, generally, the differences are smaller than the error of PIE analysis that was reported in previous SWAT validation activity, and improved results are obtained for several important fission product nuclides. This study also includes comparison between an assembly and a single pin cell geometry models.

Deuterium effect on the subcritical limit for fissile-to-hydrogen ratio

Okuno, Hiroshi; Akiyama, Hideo*; Mochizuki, Hiroki*

Journal of Nuclear Science and Technology, 40(1), p.57 - 60, 2003/01

https://doi.org/10.3327/jnst.40.57

Low-level waste (LLW) drums are required to transport as fissile material if the current IAEA's Regulations for the Safe Transport of Radioactive Material are rigorously applied. This problem is a consequence that water contents of concrete in LLW drums contained deuterium (D) in quantities more than 0.1% of fissile material mass, therefore they are not excepted from packages containing fissile material. Consideration of differences in the absorption cross sections of light hydrogen and D shows that the relative increase in the neutron multiplication factor by a presence of D in natural water for hydrogen (H)-moderated systems is not larger than 0.015%. A numerical calculation confirms that the infinite multiplication factor of a mixture of U-metal and water in a U/H mass ratio of 5% increases proportionally to the D/H atomic ratio, and that its relative increase is less than 0.03% for the D/H atomic ratio of 0.015%. The limiting fissile-to-H mass ratio of 5% in the exception rule is concluded to be applicable to H-moderated systems including D in natural water.

Revised burnup code system SWAT; Description and validation using postirradiation examination data

Suyama, Kenya; Mochizuki, Hiroki*; Kiyosumi, Takehide*

Nuclear Technology, 138(2), p.97 - 110, 2002/05

https://doi.org/10.13182/NT02-A3282

no abstracts in English

Derivation of correction factor to be applied for calculated results of PWR fuel isotopic composition by ORIGEN2 code

Suyama, Kenya; Murazaki, Minoru*; Mochizuki, Hiroki*; Nomura, Yasushi

JAERI-Tech 2001-074, 119 Pages, 2001/11

JAERI-Tech-2001-074.pdf:4.21MB

no abstracts in English

Reactivity effect of spent fuel depending on burn-up history

Hayashi, Takafumi*; Suyama, Kenya; Mochizuki, Hiroki*; Nomura, Yasushi

JAERI-Tech 2001-041, 158 Pages, 2001/06

JAERI-Tech-2001-041.pdf:5.15MB

no abstracts in English

Revised SWAT; The Integrated burnup calculation code system

Suyama, Kenya; Kiyosumi, Takehide*; Mochizuki, Hiroki*

JAERI-Data/Code 2000-027, 88 Pages, 2000/07

JAERI-Data-Code-2000-027.pdf:4.08MB

no abstracts in English

Beam-line improvement and recent results of KEK-IMSS slow-positron facility

Wada, Ken*; Mochizuki, Izumi*; Hyodo, Toshio*; Kosuge, Takashi*; Saito, Yuki*; Shidara, Tetsuo*; Osawa, Satoshi*; Ikeda, Mitsuo*; Shirakawa, Akihiro*; Furukawa, Kazuro*; et al.

no journal, , 

no abstracts in English

Application of a linac-based intense slow-positron beam to diffraction experiments

Wada, Ken*; Mochizuki, Izumi*; Hyodo, Toshio*; Shidara, Tetsuo*; Fukaya, Yuki; Maekawa, Masaki; Kawasuso, Atsuo; Michishio, Koji*; Terabe, Hiroki*; Iida, Shimpei*; et al.

no journal, , 

no abstracts in English