Systematic measurements and analyses for lead void reactivity worth in a plutonium core and two uranium cores with different enrichments

Fukushima, Masahiro; Goda, J.*; Oizumi, Akito; Bounds, J.*; Cutler, T.*; Grove, T.*; Hayes, D.*; Hutchinson, J.*; McKenzie, G.*; McSpaden, A.*; et al.

Nuclear Science and Engineering, 194(2), p.138 - 153, 2020/02

https://doi.org/10.1080/00295639.2019.1663089

To validate lead (Pb) nuclear cross sections, a series of integral experiments to measure lead void reactivity worth was conducted systematically in three fast spectra with different fuel compositions on the Comet critical assembly of the National Criticality Experiments Research Center. Previous experiments in a high-enriched uranium (HEU)/Pb and a low-enriched uranium (LEU)/Pb systems had been performed in 2016 and 2017, respectively. A follow-on experiment in a plutonium (Pu)/Pb system has been completed. The Pu/Pb system was constructed using lead plates and weapons grade plutonium plates that had been used in the Zero Power Physics Reactor (ZPPR) of Argonne National Laboratory until the 1990s. Furthermore, the HEU/Pb system was re-examined on the Comet critical assembly installed newly with a device that can guarantee the gap reproducibility with a higher accuracy and precision, and then the experimental data was re evaluated. Using the lead void reactivity worth measured in these three cores with different fuel compositions, the latest nuclear data libraries, JENDL 4.0 and ENDF/B VIII.0, were tested with the Monte Carlo calculation code MCNP version 6.1. As a result, the calculations by ENDF/B-VIII.0 were confirmed to agree with lead void reactivity worth measured in all the cores. It was furthermore found that the calculations by JENDL 4.0 overestimate by more than 20% for the Pu/Pb core while being in good agreements for the HEU/Pb and LEU/Pb cores.

Safety design report on J-PARC Transmutation Physics Experimental Facility (TEF-P)

Partitioning and Transmutation Technology Division, Nuclear Science and Engineering Center

JAEA-Technology 2017-033, 383 Pages, 2018/02

JAEA-Technology-2017-033.pdf:28.16MB

JAEA is pursuing research and development (R&D) on volume reduction and mitigation of degree of harmfulness of high-level radioactive waste. Construction of Transmutation Experimental Facility (TEF) is under planning as one of the second phase facilities in the Japan Proton Accelerator Complex (J-PARC) program to promote R&D on the transmutation technology with using accelerator driven systems (ADS). The TEF consists of two facilities: ADS Target Test Facility (TEF-T) and Transmutation Physics Experimental Facility (TEF-P). Development of spallation target technology and study on target materials are to be conducted in TEF-T with impinging a high intensity proton beam on a liquid lead-bismuth eutectic target. Whereas in TEF-P, by introducing a proton beam to minor actinide loaded cores, reactor physical properties of the cores are to be studied, and operation experiences of ADS are to be acquired. This report summarizes results of safety design for establishment permit of one of two TEF facilities, TEF-P.

On-line subcriticality measurement using a pulsed spallation neutron source

Iwamoto, Hiroki; Nishihara, Kenji; Yagi, Takahiro*; Pyeon, C.-H.*

Journal of Nuclear Science and Technology, 54(4), p.432 - 443, 2017/04

https://doi.org/10.1080/00223131.2016.1274687

Concept of transmutation experimental facility

Oigawa, Hiroyuki; Sasa, Toshinobu; Kikuchi, Kenji; Nishihara, Kenji; Kurata, Yuji; Umeno, Makoto*; Tsujimoto, Kazufumi; Saito, Shigeru; Futakawa, Masatoshi; Mizumoto, Motoharu; et al.

Proceedings of 4th International Workshop on the Utilisation and Reliability of High Power Proton Accelerators, p.507 - 517, 2005/11

Under the framework of J-PARC, the Japan Atomic Energy Research Institute (JAERI) plans to construct the Transmutation Experimental Facility (TEF). The TEF consists of two facilities: the Transmutation Physics Experimental Facility (TEF-P) and the ADS Target Test Facility (TEF-T). The TEF-P is a critical facility which can accept a 600 MeV - 10 W proton beam. The TEF-T is a material irradiation facility using a 600 MeV - 200 kW proton beam, where a Pb-Bi target is installed, but neutron multiplication by nuclear fuel will not be attempted. This report describes the purposes of the facility, the present status of the conceptual design, and the expected experiments to be performed.

Experimental study on accelerator driven subcritical reactor, JAERI's nuclear research promotion program, H12-031 (Contract research)

Shiroya, Seiji*; Misawa, Tsuyoshi*; Unesaki, Hironobu*; Ichihara, Chihiro*; Kobayashi, Keiji*; Nakamura, Hiroshi*; Shin, Kazuo*; Imanishi, Nobutsugu*; Kanazawa, Satoshi*; Mori, Takamasa

JAERI-Tech 2004-025, 93 Pages, 2004/03

JAERI-Tech-2004-025.pdf:6.69MB

In view of the future plan of Research Reactor Institute, Kyoto University, the present study consisted of (1) the transmission experiments of high energy neutrons through materials, (2) experimental simulation of ADSR using the Kyoto University Critical Assembly(KUCA), and (3) conceptual neutronics design study on KUR type ADSR using the MCNP-X code. Through the present study, valuable knowledge on the basic nuclear characteristics of ADSR, which is indispensable to promote the study on ADSR, was obtained both theoretically and experimentally. For the realization of ADSR, it is considered to be necessary to accumulate results of research steadily. For this purpose, it is inevitable (1) to compile the more precise nuclear data for the wide energy range, (2) to establish experimental techniques for reactor physics study on ADSR including subcriticality measurement and absolute neutron flux measurement, and (3) to develop neutronics calculation tools which take into account the neutron generation process by the spallation reaction and the delayed neutron behavior.

Classification of criticality calculations with correlation coefficient method and its application to OECD/NEA burnup credit benchmarks phase III-A and II-A

Okuno, Hiroshi

Journal of Nuclear Science and Technology, 40(7), p.544 - 551, 2003/07

https://doi.org/10.3327/jnst.40.544

A method for classifying benchmark results of criticality calculations according to similarity was proposed in this paper. After formulation of the method utilizing correlation coefficients, it was applied to burnup credit criticality benchmarks Phase III-A and II-A, which were conducted by the Expert Group on Burnup Credit Criticality Safety under auspices of the OECD/NEA. Phase III-A benchmark was a series of criticality calculations for irradiated BWR fuel assemblies, whereas Phase II-A benchmark was a suite of criticality calculations for irradiated PWR fuel pins. These benchmark problems and their results were summarized. The correlation coefficients were calculated and sets of benchmark results were classified according to the criterion that the correlation coefficients were no less than 0.15 for Phase III-A and 0.10 for Phase II-A benchmarks. When a couple of results were in a same group, one result was found predictable from the other. An example was shown for each of the Benchmarks. The evaluated nuclear data seemed the main factor of errors.

OECD/NEA burnup credit criticality benchmarks phase IIIB; Burnup calculations of BWR fuel assemblies for storage and transport

Okuno, Hiroshi; Naito, Yoshitaka*; Suyama, Kenya

JAERI-Research 2002-001, 181 Pages, 2002/02

JAERI-Research-2002-001.pdf:10.89MB

The report describes the final results of the Phase IIIB Benchmark conducted by the Expert Group on Burnup Credit Criticality Safety under the auspices of the OECD/NEA. The Benchmark was intended to compare the predictability of current computer code and data library combinations for the atomic number densities of an irradiated BWR fuel assembly model, which was irradiated under specific power of 25.6 MW/tHM up to 40 GWd/tHM and cooled for five years. The void fraction was assumed to be uniform and constant, at 0, 40 and 70%, during burnup. In total, 16 results were submitted from 13 institutes of 7 countries. The calculated densities of 12 actinides and 20 fission product nuclides were found mostly within a range of +- 10% relative to the average, although some results, esp. 155Eu and gadolinium isotopes, exceeded the band. Pin-wise burnup results agreed well among the participants. The results in the multiplication factor also accorded well with each other for void fractions of 0 and 40%; however some results deviated from the average noticeably for the void fraction of 70%.

Development of authentication system for the Fast Critical Assembly (FCA) Portal Monitor (P/M) and Penetration Monitor (PN/M) systems of JAERI

Ogawa, Hironobu; Mukaiyama, Takehiko

JAERI-Tech 99-041, 188 Pages, 1999/05

JAERI-Tech-99-041.pdf:10.42MB

no abstracts in English

Nuclear criticality safety of fuel rod arrays taking irregularity into account

Okuno, Hiroshi; *

Criticality Safety Challenges in the Next Decade, 0, p.150 - 155, 1997/00

no abstracts in English

FCA containment and surveillance (C/S) system

Ogawa, Hironobu; *; Mukaiyama, Takehiko

JAERI-Research 94-026, 199 Pages, 1994/11

JAERI-Research-94-026.pdf:4.97MB

no abstracts in English