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JAEA Reports

Determination of accelerator parameters for subcriticality measurement of accelerator-driven system before operation

Katano, Ryota; Nishihara, Kenji; Kondo, Yasuhiro; Meigo, Shinichiro

JAEA-Research 2021-016, 16 Pages, 2022/03

JAEA-Research-2021-016.pdf:1.65MB

It has to be confirmed that the accelerator-driven system (ADS), which is dedicated to transmuting minor actinides, is subcritical in any state by measurements. In the previous research, we have proposed a procedure in which the core safely and efficiently approaches the target subcriticality before the operation. In this procedure, the reference value of the subcriticality at the initial state is measured by the area ratio method capable of the absolute value measurement. The area ratio method uses a pulsed neutron source. However, specific and practical parameters of the accelerator for the area ratio method have not been determined. In this study, we determined the accelerator parameters with the consideration of the uncertainties derived by the dead-time of the detector and the statistical error of the count ratio. In addition, we estimate the coating amount of the sample nuclide in the assumption of the use of the fission chambers.

Journal Articles

Examination of applicability of IK method in the negative reactivity measurements

Iwanaga, Kohei; Yamane, Tsuyoshi; Nishihara, Kenji; Okajima, Shigeaki; Sekimoto, Hiroshi*; Asaoka, Takumi*

Proceedings of 11th International Conference on Nuclear Engineering (ICONE-11) (CD-ROM), 10 Pages, 2003/04

no abstracts in English

Journal Articles

Effect of higher-harmonic flux in exponential experiment for subcriticality measurement

Yamamoto, Toshihiro; Miyoshi, Yoshinori; Tonoike, Kotaro; Okamoto, Hajime*; Ida, Toshikazu*; Aoki, Shigeaki*

Journal of Nuclear Science and Technology, 40(2), p.77 - 83, 2003/02

https://doi.org/10.3327/jnst.40.77

Times Cited Count：8 Percentile：49.89(Nuclear Science & Technology)

no abstracts in English

JAEA Reports

R&D Study on on-line criticality surveillance system (IV)

Yamada, Susumu*

JNC TJ8400 2000-051, 122 Pages, 2000/02

JNC-TJ8400-2000-051.pdf:2.15MB

Developing an inexpensive on-line criticality surveillance system is required for ensuring the safety of nuclear fuel reprocessing plants. Based on the series of researches for five years, R&D study on On-line Criticality Surveillance System has been carricd out since 1996. The concept of this Criticality Surveillance System is based on the Auto-Regressive Moving Average (ARMA) model identification algorithms to the time series of signal fluctuation of a neutron detector. We have proposed several new ideas of modification to the original design of the Criticality Surveillance System, and also reported some results of numerical analysis over the DCA experiments. In those days, DOS/V personal computers with Microsoft Windows have came into wide use instead of those based on the MS-DOS, which have been popular in Japan. NEC, a major maker of MS-DOS computers, stopped the production of MS-DOS computers and changed their management policy toward production of DOS/V personal computers. Our researches have been developed using MS-DOS computers. For the effective use of these important results, it became an urgent theme to transplant all programs developed on MS_DOS computers into computers with the OS, which is not easily affected by commercialism. Since the design concept should be based on high reliability, electromagnetic disturbance-free and high expandability, and also computers have achieved remarkably high performance as well as low price in these days, these computers should be used not only as a simple signal processing unit but also a totally integrated signal analyzing system along with conventional signal analyzing software in stead of IC chips with analyzing soft wares. This configuration enables us to easily introduce newly developed techniques and to provide supplement information. Then, this approach can enhance the reliability of the Criticality Surveillance System without addition of any special devices, and also provide the flexibility of ...

JAEA Reports

None

JNC TN1400 2000-001, 371 Pages, 2000/01

JNC-TN1400-2000-001.pdf:12.26MB

no abstracts in English

JAEA Reports

None

JNC TJ1400 99-004, 110 Pages, 1999/02

JNC-TJ1400-99-004.pdf:2.42MB

no abstracts in English

JAEA Reports

Effective multiplication factor measurement by Feynman-$alpha method (3)

Mori, Tomoaki;

PNC TN9410 98-056, 72 Pages, 1998/06

PNC-TN9410-98-056.pdf:1.98MB

The sub-criticality monitoring system has been developed for criticality safety control in nuclear fuel handling plants. In the past experiments performed with the Deuterium Critical Assembly(DCA), it was confirmed that the detection of sub-criticality was possible to k $_{eff}$ =0.3. To investigate the applicability of the method to more generalized system, experiments were performed in the light-water-moderated system of the modified DCA core. From these experiments, it was confirmed that the prompt decay constant(), which was a index of the sub-criticality, was detected between k $_{eff}$ =0.623 and k $_{eff}$ 0.870 and the difference of 0.050.1k could be distinguished. The values were numerically calculated with 2D transport code TWODANT and monte carlo code KENO V.a, and the results were compared with the measured values. The differences between calculated and measured values were proved to be less than 13%, which was sufficient accuracy in the sub-criticality monitoring system. It was confirmed that Feynman- method was applicable to sub-critical measurement of the light-water-moderated system.