Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 718

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

JAEA Reports

Development of temperature evaluation method for robot test pool

Arakawa, Ryoki; Nosaki, Nobuhisa

JAEA-Technology 2018-013, 51 Pages, 2019/02

JAEA-Technology-2018-013.pdf:7.75MB

The Naraha Center for Remote Control Technology Development has various test facilities for the decommissioning work after the accident of the Fukushima Daiichi Nuclear Power Station, TEPCO Holdings, and is now promoting external use. In the test facilities, the robot test pool for the underwater robot can be used in different temperature conditions from room temperature to 60$$^{circ}$$C, maximum setting temperature. In order to clarify the temperature behavior in heating condition, a heating test from room temperature to 60$$^{circ}$$C was performed, and obtained the data. From the obtained temperature data, a heat transfer model for evaluating the temperature behavior was investigated, and the temperature evaluation method for the robot test pool was developed. This report summarizes the developed heat transfer model, and also summarizes the temperature evaluation method during heating and cooling conditions. Moreover, user's manual for the temperature evaluation code was also created.

JAEA Reports

Heating test of robot test pool

Arakawa, Ryoki; Nosaki, Nobuhisa; Hirata, Yuji*

JAEA-Technology 2018-009, 28 Pages, 2019/01

JAEA-Technology-2018-009.pdf:2.94MB

The Naraha Center for Remote Control Technology Development consists of a mock-up test building and a research management building, and various test facilities are installed in them for the decommissioning work after the accident of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings. In the test facilities, the robot test pool for the underwater robot can be tested under temperature conditions raised from room temperature to 60$$^{circ}$$C. Then, for the purpose of grasping the temperature distribution inside of the pool and the temperature rising behavior in temperature raising condition, a temperature heating test with room temperature to 60$$^{circ}$$C. (maximum setting temperature) was performed, and as well as an analytical study was performed. This report summarizes the obtained both experimental and analytical studies.

Journal Articles

Temperature measurement for in-situ crack monitoring under high-frequency loading

Naoe, Takashi; Xiong, Z.*; Futakawa, Masatoshi

Journal of Nuclear Materials, 506, p.12 - 18, 2018/08

 Times Cited Count:2 Percentile:16.17(Materials Science, Multidisciplinary)

A mercury target for neutron source (made of 316L SS) suffers not only proton and neutron radiation damage, but also cyclic impact stress caused by pressure waves. In the previous study, we carried out an ultrasonic fatigue test to investigate the gigacycle fatigue strength of 316L SS, concluding that specimen surface temperature rose abruptly more than 300$$^{circ}$$C just before failure. In this study, to clarify the mechanism of the temperature rise, we measured temperature distribution with a thermography during the fatigue test. The experimental results showed that the temperature rose locally only at the crack tip and the peak position moved with the crack propagation. We also carried out a nonlinear structural analysis by LS-DYNA to estimate the temperature rise with strain energy of elements. The analytical result showed that the heat due to plastic deformation at the crack tip is dominant for the temperature rise rather than the friction between crack surface.

Journal Articles

Temperature measurement of control rod using melt wire in High-Temperature Engineering Test Reactor (HTTR)

Hamamoto, Shimpei; Tochio, Daisuke; Ishii, Toshiaki; Sawahata, Hiroaki

Nippon Genshiryoku Gakkai Wabun Rombunshi, 16(4), p.169 - 172, 2017/12

A melt wire was installed at the tip of the control rod in order to measure the temperature of High Temperature engineering Test Reactor (HTTR). After experience with reactor scrum from the state of reactor power 100%, the melt wire was taken out from the control rod and appearance has been observed visually. It was confirmed that the melt wires with a melting point of 505 $$^{circ}$$C or less were melted, and the melt wires with a melting point of 651 $$^{circ}$$C or more were not melted. Therefore, it was found that the highest arrival temperature of tip of the control rods where the melt wires are installed reaches within the range of 505 to 651 $$^{circ}$$C. And it was found that the control rod temperature at the time of reactor scram does not exceed the using temperature criteria (900 $$^{circ}$$C) of Alloy 800H of the control rod sleeve.

Journal Articles

Saturation behavior of thermal ratcheting strain due to long range travel of temperature distribution

Okajima, Satoshi; Wakai, Takashi

Nippon Kikai Gakkai 2017-Nendo Nenji Taikai Koen Rombunshu (DVD-ROM), 5 Pages, 2017/09

It was reported that the long distance travel of temperature distribution causes a new type of thermal ratcheting, even in the absence of primary stress. In this paper, based on the results of inelastic finite element analyses, we investigated saturation behavior of thermal ratcheting strain due to long range travel of temperature distribution. As a result, we revealed that the long distance travel of temperature distribution generates plastic strain distribution made maximum at the central part. Because of the shape of the generated strain distribution, the residual stress accumulates even at the central part of the region passed through the temperature distribution. In the case with excessive long traveling of temperature distribution, the region with plastic deformation extended to the surrounding region. Otherwise, sufficient magnitude of residual stress to cause shakedown behavior accumulated on entire region, and the accumulation of the plastic strain saturated.

Journal Articles

Temperature performance of portable radiation survey instruments used for environmental monitoring and clean-up activities in Fukushima

Saegusa, Jun; Yanagisawa, Kayo; Hasumi, Atsushi; Shimizu, Takenori; Uchida, Yoshiaki*

Radiation Physics and Chemistry, 137, p.210 - 215, 2017/08

 Percentile:100(Chemistry, Physical)

Following the Fukushima Daiichi Nuclear Power Plant (NPP) accident, large-scale radiation monitoring and environmental clean-up activities have been conducted throughout the Fukushima region. Outside air temperatures there reach 40$$^{circ}$$C in summer and -20$$^{circ}$$C in winter, which are beyond the quoted range of many radiation survey instruments. For the purpose, temperature performances of four types of portable Japanese survey instruments which are widely used in Fukushima were experimentally investigated with a temperature-controlled chamber.

Journal Articles

Importance of temperature control in surrounding environment during permeability test for measuring hydraulic constants of rock

Kato, Masaji*; Nara, Yoshitaka*; Fukuda, Daisuke*; Kono, Masanori*; Sato, Toshinori; Sato, Tsutomu*; Takahashi, Manabu*

Zairyo, 65(7), p.489 - 495, 2016/07

Rock masses serve a vital function as natural barriers for geological disposal of radioactive waste; therefore, information on rock permeability is essential. Highly accurate measurement of permeability requires understanding of how temperature changes in the surrounding environment influence measurement results. We performed permeability measurement under conditions with dramatic changes of temperature in the surrounding environment to investigate the influence of such changes on the experimental results. Measurement of permeability with no temperature change was also conducted as reference. All measurements were conducted using the transient pulse method, and the sample material used was Toki granite obtained from Gifu Prefecture in central Japan. We found that temperature changes in the surrounding environment remarkably affected the pressure in reservoirs upstream and downstream, the pressure difference between them, and the confining pressure; all increased when temperature increased for our experimental system. Notably, pressure difference was affected immediately. This difference directly relates to estimation of permeability.

Journal Articles

SOL-divertor plasma simulations introducing anisotropic temperature with virtual divertor model

Togo, Satoshi*; Takizuka, Tomonori*; Nakamura, Makoto; Hoshino, Kazuo; Ogawa, Yuichi*

Journal of Nuclear Materials, 463, p.502 - 505, 2015/08

 Times Cited Count:4 Percentile:43.49(Materials Science, Multidisciplinary)

A 1D SOL-divertor plasma simulation code introducing the anisotropic ion temperature with virtual divertor model has been developed. By introducing the anisotropic ion temperature directly, the second-derivative parallel ion viscosity term in the momentum transport equation can be excluded and the boundary condition at the divertor plate becomes unnecessary. In order to express the effects of the divertor plate and accompanying sheath implicitly, the virtual divertor model has been introduced which has an artificial sinks of particle, momentum and energy. The virtual divertor model makes the periodic boundary condition available. By using this model, SOL-divertor plasmas satisfying the Bohm condition has been successfully obtained. Also investigated are the dependence of the ion temperature anisotropy on the normalized mean free path of ion and the validity of the approximated parallel ion viscosity for the Braginskii expression and the limited one.

Journal Articles

Statistical characteristics of turbulent plasmas dominated by zonal flows

Matsumoto, Taro; Kishimoto, Yasuaki; Miyato, Naoaki; Li, J.*

Journal of Plasma Physics, 72(6), p.1183 - 1187, 2006/12

 Times Cited Count:6 Percentile:74.19(Physics, Fluids & Plasmas)

no abstracts in English

Journal Articles

Magnetic phase diagram and change in 5f electronic states in NpNiGa$$_{5}$$

Honda, Fuminori; Metoki, Naoto; Kaneko, Koji; Jonen, Shintaro; Yamamoto, Etsuji; Aoki, Dai*; Shiokawa, Yoshinobu*; Shiokawa, Yoshinobu; Onuki, Yoshichika

Physica B; Condensed Matter, 378-380, p.1009 - 1010, 2006/05

 Times Cited Count:5 Percentile:69.18(Physics, Condensed Matter)

no abstracts in English

Journal Articles

Effect of high-energy ion irradiation on magnetic properties in Fe-Pt invar alloys

Ono, Fumihisa*; Kanamitsu, Hiroaki*; Matsushima, Yasushi*; Chimi, Yasuhiro; Ishikawa, Norito; Kambara, Tadashi*; Iwase, Akihiro*

Nuclear Instruments and Methods in Physics Research B, 245(1), p.166 - 170, 2006/04

 Times Cited Count:4 Percentile:62.92(Instruments & Instrumentation)

Specimens of both ordered and disordered Fe-28.3at.%Pt alloys were irradiated with 200-MeV Xe ions to the fluence of 10$$^{14}$$ ions/cm$$^{2}$$. Measurements of AC-susceptibility-temperature curves were made for each specimen before and after the irradiation by using a specially designed apparatus for rapid measurements. In contrast to the expectation from the previous results for Fe-Ni alloys, in disordered Fe-Pt invar alloy the Curie temperature, T$$_{C}$$ decreased about 15 K by the irradiation. This fact cannot be explained by considering the lattice expansion effect alone. In Fe-Pt invar alloys the effect of lattice expansion may be cancelled out by some other effects which may be originated from the large difference in atomic mass between the two elements. For ordered Fe-Pt alloy, T$$_{C}$$ decreased as large as 60 K with the same fluence. The value of T$$_{C}$$ for both ordered and disordered Fe-Pt invar alloys coincide with each other after the irradiation. This fact can be explained by considering that the ordered state becomes disordered by the irradiation.

Journal Articles

Atomic data for hollow atom production by high brightness X-rays and its applications

Moribayashi, Kengo; Kagawa, Takashi*; Kim, D. E.*

Journal of Plasma and Fusion Research SERIES, Vol.7, p.233 - 236, 2006/00

no abstracts in English

Journal Articles

Numerical visualization of herted liquid film flow behavior around a spacer in a narrow channel

Kume, Etsuo; Kitamura, Tatsuaki*; Takase, Kazuyuki; Ose, Yasuo*

Kashika Joho Gakkai-Shi, 25(Suppl.2), p.369 - 370, 2005/10

no abstracts in English

Journal Articles

Magnetic field stabilization at the JAERI AVF cyclotron

Okumura, Susumu; Kurashima, Satoshi; Miyawaki, Nobumasa; Yoshida, Kenichi; Kashiwagi, Hirotsugu; Fukuda, Mitsuhiro; Nara, Takayuki; Agematsu, Takashi; Ishibori, Ikuo; Nakamura, Yoshiteru; et al.

Proceedings of 2nd Annual Meeting of Particle Accelerator Society of Japan and 30th Linear Accelerator Meeting in Japan, p.745 - 747, 2005/07

no abstracts in English

Journal Articles

Chaos analysis from simulations of plasma turbulence driven by electron/ion temperature gradient

Matsumoto, Taro; Kishimoto, Yasuaki; Li, J.*

Denki Gakkai Purazuma Kenkyukai Shiryo (PST-05-17), p.83 - 86, 2005/03

no abstracts in English

Journal Articles

Relativistic downshift frequency effects on ECE measurements of electron temperature and density in torus plasmas

Sato, Masayasu; Isayama, Akihiko; Inagaki, Shigeru*; Nagayama, Yoshio*; Kawahata, Kazuo*; Iwama, Naofumi*

Europhysics Conference Abstracts (CD-ROM), 29C, 4 Pages, 2005/00

no abstracts in English

Journal Articles

Relativistic downshift frequency effects on electron cyclotron emission measurement; Measurements of electron density in tokamak and electron temperature in LHD

Sato, Masayasu; Isayama, Akihiko; Inagaki, Shigeru*; Nagayama, Yoshio*; Kawahata, Kazuo*; Iwama, Naofumi*

Proceedings of 13th Joint Workshop on Electron Cyclotron Emission and Electron Cyclotron Resonance Heating, p.89 - 94, 2005/00

no abstracts in English

Journal Articles

Dynamics of adatoms of the Si(111)-(7$$times$$7) surface studied by reflection high-energy positron diffraction

Fukaya, Yuki; Kawasuso, Atsuo; Hayashi, Kazuhiko; Ichimiya, Ayahiko

Physical Review B, 70(24), p.245422_1 - 245422_5, 2004/12

 Times Cited Count:31 Percentile:20.18(Materials Science, Multidisciplinary)

no abstracts in English

Journal Articles

Infrared thermography for analyzing heat transfer and fluid flow of benard-cell convection in a rectangular container with free surface

Inagaki, Terumi*; Hatori, Masakazu*; Suzuki, Tomohiro*; Shiina, Yasuaki

Proceedings of International Conference on Advanced Optical Diagnostics in Fluids, Solids and Combustion (VSJ-SPIE '04) (CD-ROM), 9 Pages, 2004/12

no abstracts in English

718 (Records 1-20 displayed on this page)