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Yokoyama, Kenji; Yamamoto, Akio*
no journal, ,
no abstracts in English
Yamashita, Susumu; Takase, Kazuyuki; Monji, Hideaki*; Yoshida, Hiroyuki
no journal, ,
no abstracts in English
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.
Nagaishi, Ryuji; Motooka, Takafumi; Yamagishi, Isao; Inoue, Masao; Matsumura, Taichi
no journal, ,
no abstracts in English
Satou, Yukihiko*; Sueki, Keisuke*; Sasa, Kimikazu*; Minowa, Haruka*; Yoshikawa, Hideki; Fujiwara, Kenso; Nakama, Shigeo
no journal, ,
We separated radioactive particles from soil and dust sample obtained around Fukushima Dai-ichi Nuclear Power Plant. Separated all particles can categorize unit-1 and unit-2 origin. And 
Sb was detected from unit-1 origin samples. Moreover, radioactive particle was made up 80 weight percent silica.
Hirouchi, Jun; Takahara, Shogo; Watanabe, Masatoshi; Munakata, Masahiro
no journal, ,
no abstracts in English
Watanabe, Masatoshi; Takahara, Shogo; Hirouchi, Jun; Munakata, Masahiro
no journal, ,
no abstracts in English
Fukano, Yoshitaka; Imaizumi, Yuya; Yoshioka, Naonori*; Akahori, Hisashi*
no journal, ,
no abstracts in English
Akahori, Hisashi*; Fukano, Yoshitaka
no journal, ,
no abstracts in English
Yoshioka, Naonori*; Fukano, Yoshitaka
no journal, ,
no abstracts in English
Koura, Hiroyuki; Chiba, Satoshi*
no journal, ,
no abstracts in English
Akaoka, Katsuaki; Oba, Masaki; Miyabe, Masabumi; Wakaida, Ikuo
no journal, ,
For quantitative analysis of the fuel debris using Laser Induced Breakdown Spectroscopy (LIBS), great deal of analysis and identification of spectra are necessary. Therefore, we tried "the analysis of the LIBS spectrum by the least-squares method" as quantitative analysis without identification and analysis of the spectra. As a result, the calibration curves for quantitative analysis could be got without them.
Iguchi, Yukihiro; Yanagihara, Satoshi*; Tezuka, Masashi; Koda, Yuya; Kato, Yasuaki
no journal, ,
Fugen Decommissioning Engineering Center is promoting Knowledge Management (KM) for the decommissioning in order to transfer knowledge and technology of the employees. One of the approaches is a KM support system by using VR and AR technology based on the 3D-CAD data.
Tsuda, Shuichi; Ogawa, Tatsuhiko; Sato, Tatsuhiko
no journal, ,
While PHITS can perform the transport calculation in the macroscopic geometries larger than 10-6 m, the information of the deposit energy distribution in smaller region is required in the evaluation of the biological effects. Although the deposit energy calculation function based on the track structure simulation in a smaller region has been in progress, the tally is only applied to the calculation in water at present. Therefore, the authors calculated the deposit energy distributions in a tissue equivalent in a micrometer scale including the contribution of the secondary particles produced through nuclear reaction, and compared with the reported experimental data. It is found that the parameters of the productions of the delta rays and the light particles should be appropriately set. These information will be used for the improvement of the microscopic deposit energy calculation function in PHITS.
Sato, Satoshi; Kwon, Saerom; Ota, Masayuki; Ochiai, Kentaro; Konno, Chikara
no journal, ,
In order to validate the nuclear data library of tungsten, integral experiments on tungsten with the DT neutron source at JAEA/FNS were performed over 20 years ago. Some calculated reaction rates underestimated the measured ones in the previous study. Background neutrons scattered in the concrete wall of the experimental room are considered to cause these underestimations. In order to reduce background neutrons, we propose a new experimental assembly and perform a new integral experiment on tungsten with the DT neutron source at JAEA/FNS in this study. A rectangular tungsten assembly of 355 mm in height, 355 mm in width and 507 mm in thickness is covered with Li
O blocks to exclude background neutrons which might affect the measured data. Using activation foils and micro fission chambers, we measure the reaction rates of the 
Nb(n,2n)
Nb, 
Al(n,
)
Na, 
In(n,n')
In, 
Au(n,
)
Au, 
W(n,)
W, 
U(n,f) and 
U(n,f) reactions. We analyze the experiment by using MCNP5-1.40 with the recent nuclear data libraries, ENDF/B-VII.1, JEFF-3.2 and JENDL-4. All the calculation results generally show good agreement with the measured ones in this experiment. It is concluded that the nuclear data of tungsten have no problem.
Kadowaki, Masanao; Terada, Hiroaki; Katata, Genki; Furuno, Akiko; Nagai, Haruyasu
no journal, ,
In case of a nuclear accident or radiological emergency, a simulation with numerical models is a powerful means in order to predict distributions of the polluted air. Although a particle model that WSPEEDI has introduced shows advantage in the synoptic scale, it costs computationally because of the large amount of airborne particles. Moreover, the model has problems with uncertainties in the calculations on long range, due to exponentially increasing errors. For the reason, in this study the atmospheric transport modeling with a finite difference method: GEARN-FDM is proposed in order to improve WSPEEDI. The advection and diffusion in the atmosphere were calculated by using a mass conservative and monotonic manner scheme (Walcek, 2000) and Crank-Nicolson method, respectively. The distributions of tracer were good agreement with the first ETEX measurements. In this session the validation and comparison will be discussed.
Sato, Kaoru; Takahashi, Fumiaki
no journal, ,
Organ doses, which are basis of dose assessment in radiation protection, are derived from ICRP reference phantoms (Male: RCP-AM, Female: RCP-AF) with body physiques of standard Caucasian. In adult, Japanese body physiques are smaller than those of Caucasian. To study impact of application of organ doses of RCP-AM and RCP-AF to dose assessment of adult Japanese, we constructed Japanese male (JM-103) and female (JF-103) phantoms with body physiques of average adult Japanese. In addition, body physiques of adult Japanese have also wide distribution. Therefore, we newly constructed DJM (Male) and DJF (Female) with 8 body physiques by changing bust, chest, waist and hip of JM-103 and JF-103. Organ doses due to external photon irradiation of DJM and DJF were calculated, and were compared with those of RCP-AM and RCP-AF. In ISO geometry at 0.3 MeV and ROT geometry at 0.6 MeV, it was found that colon doses of DJM and DJF with body physiques, which are applicable to most adult Japanese, agreed with those of RCP-AM and RCP-AF within 10 %.
Sasaki, Yuji; Tsubata, Yasuhiro; Shirasu, Noriko; Shimazaki, Shoma*
no journal, ,
no abstracts in English
Nagaya, Yasunobu
no journal, ,
no abstracts in English