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Zhang, H.*; Umehara, Yutaro*; Horiguchi, Naoki; Yoshida, Hiroyuki; Eto, Atsuro*; Mori, Shoji*
Energy, 335, p.138090_1 - 138090_18, 2025/10
Times Cited Count：0 Percentile：0.00(Thermodynamics)Nuclear power is a key low-carbon energy source for a carbon-neutral future. In boiling water reactors (BWRs), steam-water annular flow near fuel rods is crucial for reactor safety, but its high-temperature, high-pressure conditions (285
C, 7 MPa) make direct measurement challenges. To address this, we used an HFC134a-ethanol system at lower conditions (40C, 0.7 MPa) to simulate BWR annular flow. Using a high-speed camera and the constant electric current method, we analyzed liquid-film characteristics, wave velocity and frequency. We also examined surface tension and interfacial shear stress effects. Furthermore, we proposed a new correlation for base film thickness.
Shibanuma, Kiyoshi; Arai, Takashi; Hasegawa, Koichi; Hoshi, Ryo; Kamiya, Koji; Kawashima, Hisato; Kubo, Hirotaka; Masaki, Kei; Saeki, Hisashi; Sakurai, Shinji; et al.
Fusion Engineering and Design, 88(6-8), p.705 - 710, 2013/10
Times Cited Count：12 Percentile：62.01(Nuclear Science & Technology)Yoshida, Atsuro*; Higashi, Yuma*; Narabayashi, Tadashi*; Khoo Chong Weng, W.*; Arae, Kunihiko*; Tsuji, Masashi*; Ohshima, Hiroyuki; Kurihara, Akikazu
Proceedings of 19th International Conference on Nuclear Engineering (ICONE-19) (CD-ROM), 8 Pages, 2011/10
One of the design basis accidents in sodium-cooled fast reactor is sodium-water reaction at steam generator (SG). In case of a defect occurred on a heat transfer tube, the high-pressure water/vapor will spout into the low-pressure sodium surrounding outside the tube. As sodium is ordinarily quite reactive with water, this will initiate sodium-water reactions accompanied by high chemical heat generation. The liquid droplet in the reaction steam outflow would impinge on neighboring tubes to cause erosion, while the chemical reaction will cause corrosion, eventually may lead to secondary tube failure. Focusing on the erosion part, this study is to evaluate the liquid droplet impingement erosion (LDIE) rate on neighboring tubes caused by SG heat transfer tube rupture. In this paper, as a basic study, the pressure and temperature distribution of high -pressure two-phase free jet into the air is measured.
Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05
Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.
SR study of organic antiferromagnet 
'-(BEDT-TTF)
ICl under high pressureSato, Kazuhiko*; Sato, Koichi*; Yoshida, Tetsushige*; Taniguchi, Hiromi*; Goko, Tatsuro*; Ito, Takashi; Oishi, Kazuki*; Higemoto, Wataru
Physica B; Condensed Matter, 404(5-7), p.600 - 602, 2009/04
Times Cited Count：4 Percentile：19.74(Physics, Condensed Matter)Zero-field muon spin relaxation was measured for organic antiferromagnet '-(BEDT-TTF)ICl under high pressure of up to 1.37 GPa. Neel temperature, which is 22 K at ambient pressure, increases with increasing pressure and becomes approximately 48 K at 1.37 GPa. Muon precession frequency at 1.37 GPa, becomes about 5 times larger than that at ambient pressure.
Yoshida, Atsuro*; Higashi, Yuma*; William, K.*; Arae, Kunihiko*; Narabayashi, Tadashi*; Tsuji, Masashi*; Ohshima, Hiroyuki; Kurihara, Akikazu
no journal, ,
It may occur heat transfer tube failure event in steam generator of sodium-cooled fast reactor. Sodium reacts vigorously with water in the case of water leakage into sodium, the neighboring tubes are damaged by sodium-water reaction jet, tube wastage could arise from the effect of erosion and corrosion. The wastage phenomena remains to be fully elucidated by its complexity. In this study, the authors carried out the measurement experiment of temperature and pressure distribution in two-phase free jet and analyzed the wastage quantitatively from the standpoint of erosion effect.
Kato, Keisuke*; Yoshida, Atsuro*; Narabayashi, Tadashi*; Ohshima, Hiroyuki; Kurihara, Akikazu
no journal, ,
In order to quantitatively evaluate the effect of liquid droplet impacting erosion on tube wastage in case of sodium-water reaction in steam generator of sodium-cooled fast reactor, the authors have measured the behavior of water/vapor two-phase jet in water as a fundamental research using the simulated specimen of tube in steam genarator.
Yoshida, Atsuro*; Khoo Chong Weng, W.*; Narabayashi, Tadashi*; Tsuji, Masashi*; Ohshima, Hiroyuki; Kurihara, Akikazu
no journal, ,
Basic research has been carried out to clarify the wastage phenomena due to tube failure of steam generator in sodium-cooled fast reactor. The authors report the pressure distribution in two-phase free jet under high temperature and high pressure conditions measured by traverse survey.
Yoshida, Atsuro*; Khoo Chong Weng, W.*; Narabayashi, Tadashi*; Tsuji, Masashi*; Ohshima, Hiroyuki; Kurihara, Akikazu
no journal, ,
no abstracts in English
Kato, Keisuke*; Narabayashi, Tadashi*; Yoshida, Atsuro*; Arae, Kunihiko*; Ohshima, Hiroyuki; Kurihara, Akikazu
no journal, ,
There is a need for quantitative evaluation of wastage phenomena in steam generator for FBR. We focused attention on liquid droplet impingement erosion (LDIE) in wastage phenomena and performed basic study with piping group mock up specimen for quantitative evaluation of LDIE. First, we did visualization test of high pressure and high speed jet into the water. Test section mock up the crack of heat exchanger tube and neighboring heat exchanger tubes. We did the test under the following test conditions. Upstream pressure is 0.3 MPa, vapor temperature is 300 K, crack width is 0.1 mm, and crack length is 40 mm. (crack diameter is 0.2 mm) Second, we did pressure and temperature measurement test in the same test conditions as before. We evaluated jet behavior at test section by those two tests. In addition, we did two phase flow analysis of the jet with TRAC code.
Arae, Kunihiko*; Yoshida, Atsuro*; William, K.*; Narabayashi, Tadashi*; Ohshima, Hiroyuki; Kurihara, Akikazu
no journal, ,
In a Sodium-cooled Fast Reactor (SFR), liquid sodium is used as heat transfer fluid to carry the energy from the reactor core to the steam generator (SG). In case of a SG tube failure, a defect occurring on a heat transfer tube will cause the high-pressure and high-velocity water steam to spout onto the low-pressure liquid sodium filling in the space around the tube, to initiate sodium-water reaction. The steam outflow (water, sodium and sodium hydroxide) of the reaction would impinge on neighboring tube to cause erosion/corrosion, which might lead to a secondary failure. In this study, relations between several parameters and erosion rate of Mod.9Cr-1Mo in anticipated sodium-water reaction conditions were evaluated.
