Development and demonstration of in-situ SEOP He spin filter system for neutron spin analyzer on the SHARAKU polarized neutron reflectometer at J-PARC

Hayashida, Hirotoshi; Oku, Takayuki; Kira, Hiroshi*; Sakai, Kenji; Takeda, Masayasu; Sakaguchi, Yoshifumi*; Ino, Takashi*; Shinohara, Takenao; Oyama, Kenji*; Suzuki, Junichi*; et al.

Journal of Physics; Conference Series, 528, p.012020_1 - 012020_7, 2014/00

https://doi.org/10.1088/1742-6596/528/1/012020

no abstracts in English

Conceptual design of multipurpose compact research reactor; Annual report FY2010 (Joint research)

Imaizumi, Tomomi; Miyauchi, Masaru; Ito, Masayasu; Watahiki, Shunsuke; Nagata, Hiroshi; Hanakawa, Hiroki; Naka, Michihiro; Kawamata, Kazuo; Yamaura, Takayuki; Ide, Hiroshi; et al.

JAEA-Technology 2011-031, 123 Pages, 2012/01

JAEA-Technology-2011-031.pdf:16.08MB

The number of research reactors in the world is decreasing because of their aging. However, the planning to introduce the nuclear power plants is increasing in Asian countries. In these Asian countries, the key issue is the human resource development for operation and management of nuclear power plants after constructed them, and also the necessity of research reactor, which is used for lifetime extension of LWRs, progress of the science and technology, expansion of industry use, human resources training and so on, is increasing. From above backgrounds, the Neutron Irradiation and Testing Reactor Center began to discuss basic concept of a multipurpose low-power research reactor for education and training, etc. This design study is expected to contribute not only to design tool improvement and human resources development in the Neutron Irradiation and Testing Reactor Center but also to maintain and upgrade the technology on research reactors in nuclear power-related companies. This report treats the activities of the working group from July 2010 to June 2011 on the multipurpose low-power research reactor in the Neutron Irradiation and Testing Reactor Center and nuclear power-related companies.

Research on glass cells for He neutron spin filters

Sakaguchi, Yoshifumi; Kira, Hiroshi; Oku, Takayuki; Shinohara, Takenao; Suzuki, Junichi; Sakai, Kenji; Nakamura, Mitsutaka; Suzuya, Kentaro; Aizawa, Kazuya; Arai, Masatoshi; et al.

Physica B; Condensed Matter, 406(12), p.2443 - 2447, 2011/06

https://doi.org/10.1016/j.physb.2010.12.020

29th report of ITPA topical group meeting

Isayama, Akihiko; Sakakibara, Satoru*; Furukawa, Masaru*; Matsunaga, Go; Yamazaki, Kozo*; Watanabe, Kiyomasa*; Idomura, Yasuhiro; Sakamoto, Yoshiteru; Tanaka, Kenji*; Tamura, Naoki*; et al.

Purazuma, Kaku Yugo Gakkai-Shi, 86(6), p.374 - 377, 2010/06

http://ci.nii.ac.jp/naid/40017204455

no abstracts in English

Bubble flow simulations in target vessel

Haga, Katsuhiro; Kogawa, Hiroyuki; Wakui, Takashi; Naoe, Takashi; Futakawa, Masatoshi; Yamazaki, Shogo*; Tanaka, Nobuatsu*

Nuclear Instruments and Methods in Physics Research A, 600(1), p.64 - 67, 2009/02

https://doi.org/10.1016/j.nima.2008.11.063

Pitting damage on the target vessel wall caused by the pressure wave is one of the crucial issues to realize a pulsed high-power mercury target for spallation neutron sources. Micro-bubbles injection into mercury is one of prospective technologies to mitigate the pressure waves. As one of the studies for bubbling system design for pitting damage mitigation, preliminary simulation of bubble flow field in the actual target vessel was carried out and the optimal condition of bubble injection was investigated. The simulations were carried out with FLUENT. In two dimensional simulations, the bubbles of 50 m diameter could be carried more than 2000 mm, which corresponds to the length of the target vessel, with small rising height. Then three dimensional simulations were carried out for the case of the bubble diameter of 50 m and 500 m. As results, we could have prospect that bubbles are distributed to the desirable regions when they are injected in proper position according to the bubble diameter.

R&D on pressure-wave mitigation technology for pulsed high-power mercury targets; Bubble flow simulations

Haga, Katsuhiro; Futakawa, Masatoshi; Kogawa, Hiroyuki; Wakui, Takashi; Naoe, Takashi; Yamazaki, Shogo*; Tanaka, Nobuatsu*

PSI-Proceedings 07-01, p.67 - 70, 2008/01

Pressure wave, which is caused by the thermal shock in mercury at the moment the high intense proton beams bombard mercury, is a crucial issue to realize a pulsed high-power mercury target for spallation neutron sources. R&D on pressure wave mitigation technologies is carried out in JSNS. Micro-bubbles injection into mercury is one of prospective technologies to mitigate the pressure waves. The CFD simulation was carried out to investigate the injected bubble distribution in our mercury target that is influenced by bubble size and bubbling location. Also, the micro-bubbles effect was experimentally investigated from the viewpoint of pitting damage in the mercury loop with MIMTM (electro-Magnetic IMpact Testing Machine) and examined numerically from the viewpoint of bubble dynamics. As results, we confirmed that the micro-bubble is very effective to reduce the pressure response and pitting damage.

Benchmarking of nuclear fuel cycle simulators in Atomic Energy Society of Japan

Nishihara, Kenji; Takeshita, Kenji*; Shimada, Takashi*; Aizawa, Naoto*; Nakase, Masahiko*; Wada, Satoshi*; Wakasaki, Shingo*; Matsui, Minefumi*; Yasunaga, Yoshiaki*; Okamura, Tomohiro*; et al.

no journal, , 

Nuclear fuel cycle simulators (NFCSs) are widely used but suffer from uncertainties and a lack of benchmarking for large, complex scenarios. To address this, the Atomic Energy Society of Japan established a committee to develop standard reactor libraries and benchmarking scenarios. Multiple Japanese NFCSs will analyze these scenarios, and the results will be published to improve NFCS reliability.

Current status of a newly developed polarized neutron reflectometer (Sharaku) at bemaline BL 17 of J-PARC

Kubota, Masato; Takeda, Masayasu; Yamazaki, Dai; Soyama, Kazuhiko; Maruyama, Ryuji; Hayashida, Hirotoshi; Asaoka, Hidehito; Oikawa, Kenichi; Yamazaki, Tatsuya*; Aizawa, Kazuya; et al.

no journal, , 

Structure change of ODS steel by creep annealing

Yamazaki, Jin*; Onuma, Masato*; Otsuka, Satoshi; Tanno, Takashi; Toyama, Takeshi*; Mitsuhara, Masatoshi*; Nakashima, Hideharu*

no journal, , 

X-ray small angle scattering (SAXS) analysis was carried out in order to evaluate the stability of nano-sized dispersed oxide particles in oxide dispersed strengthened (ODS) steels after creep test. The size of oxide particles was not changed after creep tests at 800C and below. On the other hand, the size tended to increase in the sampled tested at over 800C. However, the SAXS analysis showed that the nano-sized YTiO oxide particle still existed in the sample after the creep test at 1000C. The result shows that dispersed nano-sized oxide particles in ODS steels have superior stability under creep test at high temperature.

Benchmark activity in Atomic Energy Society of Japan for improvement of reliability of nuclear fuel cycle simulators

Nishihara, Kenji; Takeshita, Kenji*; Shimada, Takashi*; Aizawa, Naoto*; Nakase, Masahiko*; Wada, Satoshi*; Wakasaki, Shingo*; Matsui, Minefumi*; Yasunaga, Yoshiaki*; Okamura, Tomohiro*; et al.

no journal, , 

This study presents benchmark activities conducted by a research committee of the Atomic Energy Society of Japan to enhance the reliability of nuclear fuel cycle simulators. Standard reactor libraries and phased benchmark scenarios were developed and applied to stepwise validation exercises. The results clarify consistency of simulators on burnup calculation and impact of human error. The results for 11 large-scale scenarios are also provided for future activity.