Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
4 bundleLiu, W.; Nagatake, Taku; Jiao, L.; Shibata, Mitsuhiko; Komatsu, Masao*; Takase, Kazuyuki; Yoshida, Hiroyuki
no journal, ,
To improve and validate the prediction accuracy of two - phase codes, Japan Atomic Energy Agency is working on the measurement of void faction distribution in rod bundles with using wire mesh sensors, under high pressure and high temperature conditions (2MPa, 212
C). The test section is a 44 rod bundle, in which two three - layer 99 wire mesh sensors are installed at two different axial positions. As the first step of the experiment, to validate the measuring system, we performed experiments in water - air system under atmospheric pressure, with using water and air flow rates as parameters. Void fraction distributions in the sub-channels of the rod bundle were derived in a wide flow pattern from bubbly flow to slug flow. The water flow rate, from the viewpoint of considering the natural circulation after reactor scrum, was lower than 600 kg/m
s. The data will be used to validate the void fraction correlations and two-phase evaluation codes.
Jiao, L.; Takase, Kazuyuki; Liu, W.; Nagatake, Taku; Uesawa, Shinichiro; Yoshida, Hiroyuki; Shibata, Mitsuhiko
no journal, ,
To construct a database for upwards air/water flows in a vertical pipe, extensive measurements of air/water flows in a vertical pipe using the wire-mesh sensor technology were conducted at the thermal fluid dynamic test facility TPTF of the Japan Atomic Energy Agency. The test section is 4m in length and 58mm in inner diameter, two sets of three-layers-WMS were set separately at the 1.15m and 1.65m elevation of the air injection position. Air was injected from the bottom of the pipe through 0.6mm/1mm/2mm diameter nozzles. The obtained data are characterized particularly by their quantity and their detailed information on important two-phase flow parameters (e.g. radial distribution of the void fraction, the gas velocity and the time and cross-section averaged bubble size distribution for different test section heights). In the near future, we would like to use the WMS to measure the detailed two-phase flow in sub-channels of a simulated bundle flow.
Nagatake, Taku; Takase, Kazuyuki; Yoshida, Hiroyuki
no journal, ,
no abstracts in English
Itakura, Mitsuhiro; Okita, Taira*
no journal, ,
Time to hydride precipitation in Zircalloy fuel cladding determines the lifetime of the fuel cladding of nuclear reactors. For the design of a new reactor with increased irradiation to transmute TRU elements and reduce waste, the effect of irradiation on the hydride formation must be evaluated. We carried out ab-initio calculations of vacancy cluster and the segregation of hydrogen to the cluster to deduce the fundamental parameters for the modeling of hydride formation. The results are indispensable for the design of the new reactor.
Tada, Kenichi
no journal, ,
This presentation explains the overview of the nuclear data processing code FRENDY (FRom Evaluated Nuclear Data librarY to any application) under development in JAEA.
Imaizumi, Yuya; Fukano, Yoshitaka
no journal, ,
The test result of EFM1 in the CABRI in-pile experiment which was conducted as an internationally collaborated project was analyzed by SAS4A code. The code was developed for the analysis of initiation phase of core disruptive accident. In the EFM1 test, transient overpower was imposed after the cladding melting and coolant boiling which was due to the previously imposed loss of flow. The behavior of large relocation and refreezing of the molten fuel which was caused by the heating peak after the fuel melting was one of the important point in the analysis. As a result, good agreements were observed between the results of experiment and analysis such as timings of coolant boiling, extension of boiling area and behavior of molten fuel motion.
Satoh, Daiki; Iwamoto, Yosuke; Ogawa, Tatsuhiko
no journal, ,
Many neutrons are produced in forward directions by intermediate-energy proton-induced reactions. While it is known that collective motion in a target nucleus plays important role in this neutron production, validity of theoretical model and nuclear-data library has not been examined well due to a lack of experimental data. Hence, we obtained systematic data of neutron-production double-differential cross section in the most-forward direction. The experiment was performed at TIARA of Takasaki Advanced Radiation Research Institute, JAEA. 48-, 63-, and 78-MeV proton beams were bombarded upon thin lithium, carbon, aluminum, iron, and lead target, and the neutrons produced in the most-forward direction were led to experimental room passing through a collimator. Scintillation detectors were used to the neutron detection. The measured data for lighter nuclei such as Li, C, Al showed peak structures corresponding to energy levels of the nuclei. In the spectra for Pb, one can see a broad peak caused by the collective motion of the nucleus. In comparison with the calculation results of PHITS using a theoretical model INCL and a nuclear-data library JENDL-4.0/HE, it was found that the JENDL-4.0/HE reproduces the measure spectra better than the INCL does.
Suzuki, Hideya; Tsubata, Yasuhiro; Shibata, Mitsunobu; Kurosawa, Tatsuya; Kawasaki, Tomohiro; Sagawa, Hiroshi; Matsumura, Tatsuro
no journal, ,
JAEA continues to carry out the development of the ADS(Double-strata). Mutual separation of Am(III) and Cm(III) is important for the development of the partitioning process. The separation is particularly difficult, because they have the analogous chemical behavior. Alkyl diamide amine (ADAAM), a new high-performance reagent with a simple structure, was examined for the mutual separation of Am(III) and Cu(III). The combination of ADAAM and N,N,N',N'-tetraethyldiglycolamide (TEDGA) as a masking agent shows selectivity for Am(III) over Cm(III) in highly acidic media with separation factors up to 41.
Hoshi, Takahiro; Nagaoka, Shinichi; Kudo, Atsunari; Ouchi, Masayuki; Isobe, Hiroyasu; Obu, Tomoyuki; Kurabayashi, Kazuaki
no journal, ,
no abstracts in English
Tazawa, Yujiro; Nishihara, Kenji; Sugawara, Takanori; Tsujimoto, Kazufumi
no journal, ,
Transmutation Physics Experimental Facility (TEF-P) planned in the J-PARC project uses minor actinide (MA) fuels which have large radioactivity. So it is necessary to remote handling for loading and taking these MA fuel pins to the TEF-P core. The testing equipment for fuel loading was fabricated with dummy fuel pins and the mock-up core, and performed the loading and taking test. Useful design data was obtained by the fabrication, and it was confirmed to load/take dummy fuel pins from the mock-up core without failure.
Nakata, Kotaro*; Hasegawa, Takuma*; Oyama, Takahiro*; Hataya, Ryuta*; Sasamoto, Hiroshi; Ishii, Eiichi; Miyakawa, Kazuya
no journal, ,
no abstracts in English
Pu
Am
)O
under high temperatureMatsumoto, Taku; Kato, Masato; Morimoto, Kyoichi; Sunaoshi, Takeo*
no journal, ,
The oxygen potentials of (UPuAm)O were measured as a function of oxygen to metal ratio (O/M) in the temperature range from 1673 to 1873 K by the gas equilibrium method using thermogravimetry. The measured oxygen potentials were analyzed by the point defect chemistry method. From this analysis, the oxygen potential of (UPuAm)O was represented as a function of O/M ratio and temperature.
Sato, Yuji; Fujita, Yoshihiko*; Shimomura, Tatsuo*
no journal, ,
no abstracts in English
Aizawa, Kosuke; Chikazawa, Yoshitaka; Ara, Kuniaki; Taniguchi, Yoshihiro*; Yui, Masahiro*
no journal, ,
Inspection technique in opaque liquid metal coolant is one of the important issues for safety warranty of Liquid Metal Fast Breeder Reactor (LMFBR) core. To facilitate operations and maintenance activities, an under sodium viewer (USV) has been developed in several research institutes and countries. In this study, the requirement of USV for the 750 MWe sodium fast breeder reactor was made clear on the basis of the reactor structure and the policy for the maintenance and repair. In addition, the sophistication of element technology for the USV was conducted.
Oba, Masaki; Akaoka, Katsuaki; Miyabe, Masabumi; Wakaida, Ikuo; Oba, Hironori; Ruas, A.
no journal, ,
To enhance the emission intensity of laser plasma, the characteristics of microwave assisted LIBS (MW LIBS) were measured. Using gadorinium oxide as test sample, the emission strength in the case of MW LIBS was 4 times higher than that in the case of laser pulse only.
Miyamura, Hiroko; Takahashi, Shigeo*; Idomura, Yasuhiro; Takemiya, Hiroshi
no journal, ,
We propose a level-of-detail control method for environmental monitoring datasets. The radioactive substance emitted due to the accident at the nuclear power plant in Fukushima was spread by an air current. The air dose distribution map suggests that the air current was not able to rise above a certain height in the mountainous district. We propose a new level-of-detail control method that reduces the visualization element while retaining features of two or more data elements such as the distribution of air dose and height for analyzing the relationship between two or more datasets.
-ray spectroscopy measurement systemTakamine, Jun; Rodriguez, D. C.; Koizumi, Mitsuo; Seya, Michio
no journal, ,
As the part of basic development of the active neutron nondestructive measurement techniques with collaboration between JAEA and EC-JRC, A technical development of delayed spectrometry intended for determining ratio of fissile isotopes (e.g 
U, 
Pu, 
Pu) is being performed. For the purpose of design of neutron moderator for D-T neutron source used in DGS, simulations are performed using simplified model. We report the results and a concept of system based on them.
Ruas, A.; Oba, Hironori; Akaoka, Katsuaki; Wakaida, Ikuo
no journal, ,
Ota, Yoshimi*; Nishida, Akemi; Tsubota, Haruji
no journal, ,
Many empirical formulas have been proposed for evaluating the local damage to reinforced concrete structures caused by rigid missile impact. Most of these formulas have been derived based on impact tests perpendicular to target structures and up to now few impact tests oblique to target structures has been carried out. Therefore, the purpose of this study is to propose a new formula for evaluating the local damage caused by oblique impact based on past experimental results. A new formula is derived by modifying a past empirical formula of normal impact and the conformity of the formula to the results of past oblique impact tests is discussed.
Yamashita, Susumu; Takase, Kazuyuki; Monji, Hideaki*; Yoshida, Hiroyuki
no journal, ,
no abstracts in English