Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Teshigawara, Makoto; Ikeda, Yujiro; Oi, Motoki; Harada, Masahide; Takada, Hiroshi; Kakishiro, Masanori*; Noguchi, Gaku*; Shimada, Tsubasa*; Seita, Kyoichi*; Murashima, Daisuke*; et al.
Nuclear Materials and Energy (Internet), 14, p.14 - 21, 2018/01
Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)We developed an Au-In-Cd (AuIC) decoupler material to reduce induced radioactivity instead of Ag-In-Cd one, which has a cut off energy of 1eV. In order to implement it into an actual moderator-reflector assembly, a number of critical engineering issues need to be resolved with regard to large-sized bonding between AuIC and A5083 alloys by the hot isostatic pressing process. We investigated this process in terms of the surface conditions, sizes, and heat capacities of large AuIC alloys. We also show a successful implementation of an AuIC decoupler into a reflector assembly, resulting in a remarkable reduction of radioactivity by AuIC compared to AIC without sacrificing neutronic performance.
Takada, Hiroshi; Maekawa, Fujio; Honmura, Shiro*; Yoshida, Katsuhiko*; Teraoku, Takuji*; Meigo, Shinichiro; Sakai, Akio*; Kasugai, Yoshimi; Kanechika, Shuji*; Otake, Hidenori*; et al.
Proceedings of ICANS-XVI, Volume 3, p.1115 - 1125, 2003/07
no abstracts in English
Meigo, Shinichiro; Harada, Masahide; Teraoku, Takuji*; Maekawa, Fujio
Proceedings of ICANS-XVI, Volume 3, p.1175 - 1180, 2003/07
It is important to monitor the proton beam for the high intensity pulse spallation target. Especially for the beam halo, which may irradiate the bulk surrounding the target, it is important to be observed to prevent causing heat spot in the shielding bulk. At JSNS, a proton beam monitors are located at front of the target. These monitors are assembled with the proton beam window. Since this scheme increases the radiation on the monitor due to the beam loss at the windows, it may arise heat deposition on the monitor. Therefore, heat deposition is calculated with NMTC/JAM. It is found that the heat deposition for normal operation is less than 0.1 W/cc.
Honmura, Shiro*; Teraoku, Takuji*; Yoshida, Katsuhiko*; Takada, Hiroshi; Maekawa, Fujio; Kasugai, Yoshimi; Hino, Ryutaro; Watanabe, Noboru; Furusaka, Michihiro
JAERI-Tech 2003-054, 62 Pages, 2003/06
The JAERI and the KEK are jointly on the way of constructing facilities under the High-Intensity Proton Accelerator Project (J-PARC). The Materials and Life Science Facility is one of major facilities comprising a 1MW pulsed neutron source (JSNS). The neutrons are to be utilized for advanced researches in fields of materials and life science, and so on. In designing helium-vessel, it is important to assure structural integrity of the helium-vessel against earthquakes. It is also important to manufacture accurately neutron view ports. In-vessel components need to be replaced by remote handling after a certain period of operation due to radiation damages. To make the replacement steadily and easily, the helium-vessel has to provide suitable support, positioning and sealing structures. This report describes bases and conditions for deigning the helium-vessel, and summarizes basic structural specifications of the helium-vessel which are determined with structure strength and temperature analyses.
Teraoku, Takuji*; Terada, Atsuhiko*; Maekawa, Fujio; Meigo, Shinichiro; Kaminaga, Masanori; Ishikura, Shuichi*; Hino, Ryutaro
JAERI-Tech 2003-026, 77 Pages, 2003/03
A 1-MW spallation neutron source aiming at materials and life science researches will be constructed under the JAERI-KEK Proton Accelerator Project(J-PARC). The proton beam window functions as a boundary wall between a high vacuum area and a helium atmosphere and it is cooled by light water because high heat-density is generated in the window material by interactions with the proton beam. Then, uniformity of the water flow is requested at the window to suppress a hot-spot that causes excessive thermal stress and cooling water boiling. Also, the window has to be strong enough in its structure for inner stress due to water pressure and thermal stress due to heat generation. In this report, we propose two types of proton beam windows, flat-type and curved-type. We evaluated the strength of structure and thermal hydraulic analysis. As a result, it was found that sufficient heat removal was assured with uniform water flow at the window, and the stress could be maintained below allowable stress values. Accordingly, it was confirmed that the proton beam window designs were feasible.
Kaminaga, Masanori; Haga, Katsuhiro; Aso, Tomokazu; Kinoshita, Hidetaka; Kogawa, Hiroyuki; Ishikura, Shuichi*; Terada, Atsuhiko*; Kobayashi, Kaoru*; Adachi, Junichi*; Teraoku, Takuji*; et al.
Proceedings of American Nuclear Society Conference "Nuclear Applications in the New Millennium" (AccApp-ADTTA '01) (CD-ROM), 9 Pages, 2002/00
no abstracts in English
Kawada, Koji; ; Ohno, Shuji; ; Miyake, Osamu; Tanabe, Hiromi
JNC TN9400 2000-089, 258 Pages, 2000/08
As a part of the work for investigating the sodium leak accident which occurred in the Monju reactor (hereinafter referred to as Monju) on December 8, 1995, threetests, (1)a sodium leaktest, (2)a sodium leak and fire test-I, and(3)a sodium leak and fire test-II, were carried out at OEC/PNC, The main objectives of these tests were to confirm the leak and burning behavior of sodium from the damaged thermometer, and the effects of the sodium fire on the integrity of the surrounding structure. This report describes the results of the sodium fire test-I carried out as a preliminary test. The test was performed usjng the SOLFA-2 (Sodium Leak, Fire and Aerosol) facility on April 8, 1996. In this test, sodium heated to 480C was leaked for approximately l.5 hours from a leak simulating apparatus and caused to drop onto a ventilation duct and a grating with the same dimensions and layout as those in Monju. The main conclusions obtained from the test are shown below: (1)Observation from video cameras in the test revealed that jn the early stages of the sodium leak, sodium dripped out of the flexible tube of the thermometer. This dripping and burning expanded in range as the sodium splashed on the duct. (2)No damage to the duct itself was detected. However, the aluminum louver frame of the ventilation duct's lower inlet was damaged. lts machine screws came off, leaving half of the grill (on the grating side) detached. (3)NO large hole, like the one seen at Monju, was found when the grating was removed from the testing system for inspection, although the area centered on the point were the sodium dripped was damaged in a way indicating the first stages of grating failure. The 5mm square lattice was corroded through in some parts, and numerous blades (originally 3.2 mm thick) had become sharpened like the blade of a knife. (4)The burning pan underside thermocouple near the leak point measured 700C in within approximately 10 minutes, and for the next ...
Kawada, Koji; Ohno, Shuji; Miyake, Osamu; ; ; Tanabe, Hiromi
PNC TN9410 97-036, 243 Pages, 1997/01
As a part of the work for investigating the sodium leak accident which occurred in Monju on December 8, 1995, three tests, (1)sodium leak test, (2)sodium leak and fire test-I, and (3)sodium leak and fire test-II, were carried out at OEC/PNC. Main objectives of these tests are to confirm leak and burning behavior of sodium from the damaged thermometer, and effects of the sodium fire on integrity of the surrounding structure, etc. This report describes the result of the sodium fire test-I carried out as a preliminary test. The test was performed using SOLFA-2 (Sodium Leak, Fire and Aerosol) facility on April 8, 1996. In this test, sodium heated to 480C was leaked for approximately 1.5 hours from a leak simulated apparatus and caused to drop onto a ventilation duct and a grating with the same dimensions and layout as those in Monju. The main conclusions obtained from the test are shown as below. (1)Observation from video cameras in the test revealed that in early stages of sodium leak, sodium dropped down out of the flexible tube of thermometer in drips. This dripping and burning were expanded in range as sodium splashed on the duct. (2)No damage to the duct itself was detected. However, the aluminum louver frame of the ventilation duct's lower inlet was damaged: Its machine screws had come off, leaving half of the grill (on the grating side) detached. (3)No large hole, like one seen at Monju, were found when the grating was removed from the testing system for inspection, although the area centered on the point that the sodium attacked was damaged in a way indicating the first stages of grating failure: The 5-mm- square lattice was corroded through in some parts, and many blades (originally 3.2 mm thick) had become like the blade of a sharp knife. (4)The burning pan underside thermocouple near the leak point measured 700C in roughly 10 minutes, and for the next hour remained stable between 740C and 770C. There was a ...