Iwamoto, Osamu; Iwamoto, Nobuyuki; Kunieda, Satoshi; Minato, Futoshi; Nakayama, Shinsuke; Abe, Yutaka*; Tsubakihara, Kosuke*; Okumura, Shin*; Ishizuka, Chikako*; Yoshida, Tadashi*; et al.
Journal of Nuclear Science and Technology, 60(1), p.1 - 60, 2023/01
Kumagai, Masayoshi*; Kuroda, Masatoshi*; Matsuno, Takashi*; Harjo, S.; Akita, Koichi*
Materials & Design, 221, p.110965_1 - 110965_8, 2022/09
Hori, Satoshi*; Kanno, Ryoji*; Kwon, O.*; Kato, Yuki*; Yamada, Takeshi*; Matsuura, Masato*; Yonemura, Masao*; Kamiyama, Takashi*; Shibata, Kaoru; Kawakita, Yukinobu
Journal of Physical Chemistry C, 126(22), p.9518 - 9527, 2022/06
Obayashi, Hironari; Yamaki, Kenichi*; Yoshimoto, Hidemitsu*; Kita, Satoshi*; Wan, T.*; Sasa, Toshinobu
JAEA-Technology 2021-035, 66 Pages, 2022/03
Construction of Transmutation Experimental Facility (TEF) is under planning in Japan Proton Accelerator Research Complex (J-PARC) program to promote R&Ds on realization of transmutation technology by an accelerator driven system (ADS). As a facility of TEF, ADS Target Test Facility (TEF-T) will provide a spallation target to study target technology and perform post irradiation examination (PIE) of candidate materials of ADS. In ADS, lead-bismuth eutectic (LBE) alloy is used as a spallation target material and a core coolant. As is well known, LBE has corrosive to structural materials hence each component of the target system should provide compatibility with LBE. In addition, instrumentations for LBE are restricted by the target operation condition such as high temperature and irradiation environment. The devices for LBE have been developed individually to achieve the LBE target system. "Integrated Multi-functional MOckup for TEF-T Real-scale TArget Loop, IMMORTAL" was fabricated as a mock-up test loop of the target for the purpose of the integration testing of individually developed devices. This report describes an overview of IMMORTAL and the design of the installed devices.
Saito, Shigeru; Wan, T.*; Okubo, Nariaki; Kita, Satoshi*; Obayashi, Hironari; Sasa, Toshinobu
JAEA-Technology 2021-034, 94 Pages, 2022/03
Lead-bismuth eutectic alloy (LBE) is a major candidate for a spallation target material and core coolant of an accelerator driven system (ADS) which has been developed in the Japan Atomic Energy Agency (JAEA) to transmute high-level radioactive wastes. A proton irradiation facility to build a material irradiation database for future ADS development is under considering in the J-PARC. To realize both the ADS and the above-mentioned facility, there are many issues on operational safety of LBE to be solved. Especially, corrosion data for the major materials such as T91 (Modified 9Cr-1Mo steel) and SS316L at the temperature range between 400 and 550 C under the conditions of flowing LBE with a controlled oxygen are not sufficient to design the ADS and the facility. JAEA developed a new large-scale corrosion test loop named "OLLOCHI (Oxygen-controlled LBE LOop for Corrosion tests in HIgh-temperature)" aiming to perform the compatibility tests between the LBE and the steels, as well as to develop the LBE operation technology. OLLOCHI has a function to automatically control the oxygen concentration in LBE. The maximum temperature at the regions of high-temperature and low-temperature of the OLLOCHI are 550 C and 450 C respectively to cover the ADS designed condition. As a result of 2,000 hours operation, it was demonstrated that the OLLOCHI showed the designed performance. In this report, outline of the OLLOCHI, details of the components, results of characteristic tests, and the future experimental plan are described.
Obayashi, Hironari; Yamaki, Kenichi*; Kita, Satoshi*; Ariyoshi, Gen; Sasa, Toshinobu
Proceedings of 19th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-19) (Internet), 11 Pages, 2022/03
JAEA developed a non-contact type flowmeter that two ultrasonic sensors were installed on outer surface of a cylindrical-shaped test section. The considerable issue of the realization was multiple reflection of emitted signal in the piping. Furthermore, wettability between LBE and inner surface of the test section was one of the important issue on the ultrasonic technique. To mitigate the multiple reflection, a critical angle as an incident angle not to produce a longitudinal wave on the solid / solid boundary was applied. And fine mirror-finished treatment was applied to the inner surface of the test section to ensure wettability. As a result of experiment at 350 degrees C, the observed correlation value between the non-contact type and the established plug type was 0.9986. Additionally, the developed non-contact type provided its sufficiently stable output during a long-term test more than 1,500 hours.
Okita, Taira*; Terayama, Satoshi*; Tsugawa, Kiyoto*; Kobayashi, Keita; Okumura, Masahiko; Itakura, Mitsuhiro; Suzuki, Katsuyuki*
Computational Materials Science, 202, p.110865_1 - 110865_9, 2022/02
Nakagawa, Hiroshi; Saio, Tomohide*; Nagao, Michihiro*; Inoue, Rintaro*; Sugiyama, Masaaki*; Ajito, Satoshi; Tominaga, Taiki*; Kawakita, Yukinobu
Biophysical Journal, 120(16), p.3341 - 3354, 2021/08
A multi-domain protein can have various conformations in solution. Interactions with other molecules result in the stabilization of one of the conformations and change in the domain dynamics. SAXS, a well-established experimental technique, can be employed to elucidate the conformation of a multi-domain protein in solution. NSE spectroscopy is a promising technique for recording the domain dynamics in nanosecond and nanometer scale. Despite the great efforts, there are still under development. Thus, we quantitatively removed the contribution of diffusion dynamics and hydrodynamic interactions from the NSE data via incoherent scattering, revealing the differences in the domain dynamics of the three functional states of a multi-domain protein, MurD. The differences among the three states can be explained by two domain modes.
Terayama, Satoshi*; Iwase, Yuki*; Hayakawa, Sho*; Okita, Taira*; Itakura, Mitsuhiro; Suzuki, Katsuyuki*
Computational Materials Science, 195, p.110479_1 - 110479_12, 2021/07
Kumagai, Masayoshi*; Akita, Koichi*; Kuroda, Masatoshi*; Harjo, S.
Materials Science & Engineering A, 820, p.141582_1 - 141582_9, 2021/07
Saito, Shigeru; Wan, T.*; Okubo, Nariaki; Obayashi, Hironari; Watanabe, Nao; Ohdaira, Naoya*; Kinoshita, Hidetaka; Yamaki, Kenichi*; Kita, Satoshi*; Yoshimoto, Hidemitsu*; et al.
JPS Conference Proceedings (Internet), 33, p.011041_1 - 011041_6, 2021/03
An Accelerator Driven System (ADS) for waste transmutation investigated in JAEA employs lead-bismuth eutectic (LBE) as a neutron production target material and coolant. The neutrons are to be produced via the spallation with 1.5 GeV proton beam injection. As materials irradiation data are important for ADS development, JAEA plans to construct an irradiation facility with LBE neutron production target in J-PARC. There are many technical issues on LBE for practical use. In JAEA, various R&Ds are being carried out. Concerning corrosion study, conditioning operation and functional tests of OLLOCHI started. Oxygen concentration control technology has also developing. In the large scale LBE loop experiment, the operation for steady state and transient experiments was performed by using IMMORTAL. In the area of instrument, development of ultrasonic flow meter and freeze seal valve are progressing as a key technology for the LBE loop system. Investigation of behavior of impurities in LBE, which is important for design of the irradiation facility, started. In this paper, the status of the LBE studies and experimental plan will be presented.
Obayashi, Hironari; Yoshimoto, Hidemitsu*; Kita, Satoshi*; Yamaki, Kenichi*; Wan, T.*; Saito, Shigeru; Sasa, Toshinobu
JPS Conference Proceedings (Internet), 33, p.011048_1 - 011048_6, 2021/03
Tominaga, Taiki*; Kobayashi, Makoto*; Yamada, Takeshi*; Matsuura, Masato*; Kawakita, Yukinobu; Kasai, Satoshi*
JPS Conference Proceedings (Internet), 33, p.011095_1 - 011095_5, 2021/03
A vertical movement type of sample changer for the neutron spectrometer BL02, J-PARC MLF was developed for our top-loading type cryostat. The sample changer, termed as "PEACE", can control reproducibility of the irradiated position using guides made of polyether ether ketone. The variation between the background scattering profiles of three sample positions was found to be less than plus minus 1.6%. This result is reasonable, considering the deviation of sample position of less than plus minus 0.3 mm from the vertical axis.
Yamaki, Kenichi*; Kita, Satoshi*; Obayashi, Hironari; Ariyoshi, Gen; Saito, Shigeru; Sasa, Toshinobu
JAEA-Technology 2020-021, 26 Pages, 2021/02
As digitalization of measuring instruments, Programmable Logic Controller is mainly used for controlling large-scale devices, and many test devices are controlled in digital. Together with increase of the data storage capacity, it has become possible to record the measured values over the entire experimental period. By collecting the entire experimental data, it became easy to appropriately record the test environment during the corrosion test of materials and to analyze the changes and transients during continuous operation from various viewpoints. On the other hand, in a long-term test, the large number of measurement data were recorded, which requires long time for data processing and data extraction for analyses. In addition, it is necessary to pay attention to organize the data collected by different data formats. To solve these problems, a processing tool were produced to extract and process the data efficiently from the sequencer installed in the lead-bismuth test device.
Ikushima, Kazuki*; Shibahara, Masakazu*; Kawajiri, Yoshitaka*; Okimi, Yui*; Uchida, Tomoki*; Akita, Koichi*; Suzuki, Hiroshi; Morooka, Satoshi
Nihon Senpaku Kaiyo Kogakkai Rombunshu, (30), p.123 - 130, 2019/12
In this research, the contour method was applied to measure the residual stress distribution of a bead-on-plate specimen. The measured residual stress distribution was compared with those measured by neutron diffraction method and calculated by thermal elastic plastic finite element analysis. As a result, it was found that the residual stress distribution obtained by these three methods are in good agreement. In addition, the equilibrium of reaction force on cut plane was considered in the contour method to measure residual stresses in asymmetric cutting which is assumed in the measurement of real structures. The proposed method was applied to the measurement of the residual stress in the multi-pass welded joint. The measured results indicated that the proposed method can measure the residual stress distribution in multi-pass welded joint in asymmetric test specimen.
Obayashi, Hironari; Yamaki, Kenichi; Kita, Satoshi; Yoshimoto, Hidemitsu; Wan, T.; Saito, Shigeru; Sasa, Toshinobu
Proceedings of 18th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-18) (USB Flash Drive), p.262 - 274, 2019/08
Construction of an experimental facility using LBE spallation target is under planning in the framework of J-PARC project to understand the compatibility of candidate ADS structural materials under flowing high temperature LBE environment with proton / neutron irradiation. We constructed a mock-up test loop, IMMORTAL to verify the feasibility of a primary cooling system in the target system. Including the layout considering remote maintainability, the same design as the actual JAEA's LBE target is reflected in most devices of IMMORTAL such as an electromagnetic pump (EMP), a heat exchanger and instrumentations. During the integrated tests, the individually developed devices of LBE loop system worked without significant malfunction. Several experimental data to verify the safety analysis model for LBE loop system using RELAP5-3D was acquired by simulation experiment of transient events such as beam over power and decrease of forced cooling.
Sugawara, Takanori; Kita, Satoshi*; Yoshimoto, Hidemitsu*; Okubo, Nariaki
JAEA-Technology 2018-008, 26 Pages, 2018/09
The oxygen sensors to measure the oxygen concentration in liquid LBE (lead-bismuth eutectic) were fabricated and tested for future use in LBE-cooled ADS (accelerator-driven system) or LBE test loops. The following tests were performed; estimation of catalyst application range, freeze seal structure and estimation of gamma-ray irradiation effect. For the estimation of the catalyst application range, it was confirmed that the measurement accuracy became worse in low LBE temperature as the application range became small. For the freeze seal structure, we realized the structure to prevent the LBE leakage with 0.5 MPa pressure condition. For the estimation of gamma-ray irradiation effect, the ex-situ test was carried out and it was observed that there was little effect by 4 MGy gamma-ray irradiation.
Ikushima, Kazuki*; Shibahara, Masakazu*; Nishikawa, Satoru*; Furukawa, Takashi*; Akita, Koichi; Suzuki, Hiroshi; Morooka, Satoshi
E-Journal of Advanced Maintenance (Internet), 9(3), p.NT87_1 - NT87_5, 2017/11
Kuroda, Masatoshi*; Kamaya, Masayuki*; Yamada, Teruaki*; Akita, Koichi
Nihon Kikai Gakkai Rombunshu (Internet), 83(852), p.17-00072_1 - 17-00072_7, 2017/07
In order to assess the fatigue damage of austenitic stainless steels by electron backscatter diffraction (EBSD) method more simply and easily, it should be more preferable to use a commercially available general-purpose EBSD analysis software rather than to employ an in-house developed EBSD analysis programme. In the present study, EBSD measurement was performed for Type 316 austenitic stainless steels subjected to cyclic loading, and the applicability of the EBSD parameter relevant to the pattern quality, which could be obtained by the commercial software, to the fatigue damage assessment was discussed by comparing the other EBSD parameter of the averaged local misorientation (Mave), which could be calculated by the in-house developed programme. As a result, the EBSD parameter relevant to the pattern quality, which signified the full width at half maximum (FWHM) of the histogram distribution of the image quality (IQ), was saturated at the beginning stage of the fatigue cycles, while Mave was increased monotonically with the cycles. This suggested that the FWHM of IQ could be useful to detect the initial stage of the fatigue damage, while Mave was suitable for the quantitative evaluation of the fatigue damage. XRD measurement was also carried out for the same samples employed in the EBSD measurement, and the XRD data was compared with the EBSD data to discuss the crystallographic mechanism of the change in the FWHM of IQ. As a result, it was found that the FWHM of the (111) XRD peak correlated well with the FWHM of IQ. Because the (111) plane in fcc metal such as austenitic stainless steel was most preferable for slip system, this implied that the change in the distribution of the pattern quality generated by the fatigue loading could be due to the slip deformation.
Ikushima, Kazuki*; Kitani, Yuji*; Shibahara, Masakazu*; Nishikawa, Satoru*; Furukawa, Takashi*; Akita, Koichi; Suzuki, Hiroshi; Morooka, Satoshi
Yosetsu Gakkai Rombunshu (Internet), 35(2), p.75s - 79s, 2017/06