Kumagai, Tomohisa*; Miura, Yasufumi*; Miura, Naoki*; Marie, S.*; Almahdi, R.*; Mano, Akihiro; Li, Y.; Katsuyama, Jinya; Wada, Yoshitaka*; Hwang, J.-H.*; et al.
Journal of Pressure Vessel Technology, 144(1), p.011509_1 - 011509_18, 2022/02
To predict fracture behavior for ductile materials, some ductile fracture simulation methods different from classical approaches have been investigated based on appropriate models of ductile fracture. For the future use of the methods to overcome restrictions of classical approaches, the applicability to the actual components is of concern. In this study, two benchmark problems on the fracture tests supposing actual components were provided to investigate prediction ability of simulation methods containing parameter decisions. One was the circumferentially through-wall and surface cracked pipes subjected to monotonic bending, and the other was the circumferentially through-wall cracked pipes subjected to cyclic bending. Participants predicted the ductile crack propagation behavior by their own approaches, including FEM employed GTN yielding function with void ratio criterion, are FEM employed GTN yielding function, FEM with fracture strain or energy criterion modified by stress triaxiality, XFEM with J or delta J criterion, FEM with stress triaxiality and plastic strain based ductile crack propagation using FEM, and elastic-plastic peridynamics. Both the deformation and the crack propagation behaviors for monotonic bending were well reproduced, while few participants reproduced those for cyclic bending. To reproduce pipe deformation and fracture behaviors, most of groups needed parameters which were determined toreproduce pipe deformation and fracture behaviors in benchmark problems themselves and it is still difficult to reproduce them by using parameters only from basic materials tests.
Pavao, R.*; Gubler, P.; Fernandez-Soler, P.*; Nieves, J.*; Oka, Makoto; Takahashi, Toru*
Physics Letters B, 820, p.136473_1 - 136473_8, 2021/09
Samarakoon, A. M.*; Takahashi, Mitsuru*; Zhang, D.*; Yang, J.*; Katayama, Naoyuki*; Sinclair, R.*; Zhou, H. D.*; Diallo, S. O.*; Ehlers, G.*; Tennant, D. A.*; et al.
Scientific Reports (Internet), 7(1), p.12053_1 - 12053_8, 2017/09
Okumura, Yoshikazu; Gobin, R.*; Knaster, J.*; Heidinger, R.*; Ayala, J.-M.*; Bolzon, B.*; Cara, P.*; Chauvin, N.*; Chel, S.*; Gex, D.*; et al.
Review of Scientific Instruments, 87(2), p.02A739_1 - 02A739_3, 2016/02
IFMIF is an accelerator based neutron facility having two set of linear accelerators each producing 125mA/CW deuterium ion beams (250mA in total) at 40MeV. The LIPAc (Linear IFMIF Prototype Accelerator) being developed in the IFMIF-EVEDA project consists of an injector, a RFQ accelerator, and a part of superconducting Linac, whose target is to demonstrate 125mA/CW deuterium ion beam acceleration up to 9MeV. The injector has been developed in CEA Saclay and already demonstrated 140mA/100keV deuterium beam. The injector was disassembled and delivered to the International Fusion Energy Research Center (IFERC) in Rokkasho, Japan, and the commissioning has started after its reassembly 2014; the first beam production has been achieved in November 2014. Up to now, 100keV/120mA/CW hydrogen ion beam has been produced with a low beam emittance of 0.2 .mm.mrad (rms, normalized).
Shinto, Katsuhiro; Sene, F.*; Ayala, J.-M.*; Bolzon, B.*; Chauvin, N.*; Gobin, R.*; Ichimiya, Ryo; Ihara, Akira; Ikeda, Yukiharu; Kasugai, Atsushi; et al.
Review of Scientific Instruments, 87(2), p.02A727_1 - 02A727_3, 2016/02
Shinto, Katsuhiro; Ichikawa, Masahiro; Takahashi, Hiroki; Kondo, Keitaro; Kasugai, Atsushi; Gobin, R.*; Sene, F.*; Chauvin, N.*; Ayala, J.-M.*; Marqueta, A.*; et al.
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.493 - 495, 2015/09
Development of the prototype accelerator (LIPAc) for the engineering validation of the International Fusion Materials Irradiation Facility (IFMIF) which is an accelerator driven neutron source has been progressed at Rokkasho. The LIPAc is a deuteron linear accelerator consisting of an injector, a radio-frequency quadrupole (RFQ) linac and a superconducting linac. The objective of LIPAc is to produce a CW beam with the energy and current of 9 MeV and 125 mA, respectively. The injector was developed at CEA/Saclay and succeeded to produce CW proton and deuteron beams of 100 keV/140 mA by autumn 2012. After the test at CEA/Saclay, the injector was shipped to the International Fusion Energy Research Centre (IFERC) in Rokkasho, Aomori and started to reassemble from the end of 2013. It was successfully produced proton beams in November 2014 at Rokkasho. While the ion source conditioning was done, the beam test was progressed. In this paper, the present status of the LIPAc injector at Rokkasho with some experimental results will be presented.
Okumura, Yoshikazu; Ayala, J.-M.*; Bolzon, B.*; Cara, P.*; Chauvin, N.*; Chel, S.*; Gex, D.*; Gobin, R.*; Harrault, F.*; Heidinger, R.*; et al.
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.203 - 205, 2015/09
Under the framework of Broader Approach (BA) agreement between Japan and Euratom, IFMIF/EVEDA project was launched in 2007 to validate the key technologies to realize IFMIF. The most crucial technology to realize IFMIF is two set of linear accelerator each producing 125mA/CW deuterium ion beams up to 40MeV. The prototype accelerator, whose target is 125mA/CW deuterium ion beam acceleration up to 9MeV, is being developed in International Fusion Research Energy Center (IFERC) in Rokkasho, Japan. The injector developed in CEA Saclay was delivered in Rokkasho in 2014, and is under commissioning. Up to now, 100keV/120mA/CW hydrogen ion beams and 100keV/90mA/CW duty deuterium ion beams are successfully produced with a low beam emittance of 0.21 .mm.mrad (rms, normalized). Delivery of RFQ components will start in 2015, followed by the installation of RF power supplies in 2015.
Ishigami, Keisuke*; Yoshimatsu, Kohei*; Toyota, Daisuke*; Takizawa, Masaru*; Yoshida, Teppei*; Shibata, Goro*; Harano, Takayuki*; Takahashi, Yukio*; Kadono, Toshiharu*; Verma, V. K.*; et al.
Physical Review B, 92(6), p.064402_1 - 064402_5, 2015/08
Attie, O.*; Jayaprakash, A.*; Shah, H.*; Paulsen, I. T.*; Morino, Masato*; Takahashi, Yuka*; Narumi, Issey*; Sachidanandam, R.*; Sato, Katsuya; Ito, Masahiro*; et al.
Genome Announcements (Internet), 2(6), p.e01175-14_1 - e01175-14_2, 2014/11
Shinto, Katsuhiro; Ichikawa, Masahiro; Takahashi, Yasuyuki*; Kubo, Takashi*; Tsutsumi, Kazuyoshi; Kikuchi, Takayuki; Kasugai, Atsushi; Sugimoto, Masayoshi; Gobin, R.*; Girardot, P.*; et al.
Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1009 - 1012, 2014/10
The prototype accelerator is being developed as an engineering validation for the International Fusion Materials Irradiation Facility (IFMIF) equipped with an accelerator-driven-type neutron source for developing fusion reactor materials. This prototype accelerator is a deuteron linear accelerator consisting of an injector, an RFQ, a superconducting linac and their auxiliaries. It aims to produce a CW D beam with the energy and current of 9 MeV/125 mA. The injector test was completed at CEA/Saclay in 2012 for producing a CW H beam and a CW D beam with the energy and current of 100 keV/140 mA. After the beam test at CEA/Saclay, the injector was transported to the International Fusion Energy Research Centre (IFERC) located in Rokkasho, Aomori, Japan. In the end of 2013, installation of the injector was started at IFERC for the injector beam test beginning from summer 2014 in order to obtain better beam qualities to be satisfied with the injection and acceleration of the following accelerators. In this paper, some results of the injector beam test performed at CEA/Saclay and the status quo of the installation of the injector at IFERC are presented.
Takahashi, Yukio*; Kadono, Toshiharu*; Yamamoto, Shimpei*; Singh, V. R.*; Verma, V.*; Ishigami, Keisuke*; Shibata, Goro*; Harano, Takayuki*; Takeda, Yukiharu; Okane, Tetsuo; et al.
Physical Review B, 90(2), p.024423_1 - 024423_5, 2014/07
Sako, Hiroyuki; Ahn, J. K.*; Baek, K. H.*; Bassalleck, B.*; Fujioka, H.*; Guo, L.*; Hasegawa, Shoichi; Hicks, K.*; Honda, R.*; Hwang, S. H.*; et al.
Journal of Instrumentation (Internet), 9(4), p.C04009_1 - C04009_10, 2014/04
A TPC has been developed for J-PARC E42 experiment to search for H-dibaryon in (, ) reaction. An event with 2 and 2 protons decaying from H-dibaryon is searched for inside the TPC. The TPC has octagonal prism shape drift volume with about 50 cm diameter with 55 cm drift length filled with Ar-CH (90:10) gas. At the end of the drift volume, 3-layer GEMs are equipped. In order to analyze momenta of produced particles, the TPC is applied with 1 T dipole magnetic field parallel to the drift electric field with a superconducting Helmholz magnet. In order to maximize the acceptance of H-dibaryon events, a diamond target is installed inside the TPC drift volume, in a cylindrical hole opened from the top to the middle of the drift volume. Since extremely high-rate beam is directly injected into the TPC drift volume to the target, a gating grid and GEMs are adopted to suppress positive-ion feedback.
Takasaki, Koji; Yasumune, Takashi; Onishi, Takashi; Nakamura, Keisuke; Ishimi, Akihiro; Ito, Chikara; Osaka, Masahiko; Ono, Masashi*; Hatakeyama, Shuichi*; Takahashi, Hiroyuki*; et al.
JAEA-Research 2013-043, 33 Pages, 2014/01
In the Fukushima Daiichi Nuclear Power Plant, it is assumed that the core fuels melted partially or wholly, and the normal technique of accounting for a fuel assembly is not applicable. Therefore, it is necessary to develop the transparent and rational technique of accounting in the process of collection and storage of fuel debris. In this research, an application of the superconducting phase Transition Edge Sensor microcalorimeter (TES microcalorimeter) is studied for the accounting of nuclear materials in the fuel debris. It is expected that the detailed information of nuclear materials and fission products in fuel debris is obtained by using a high-resolution characteristic of TES microcalorimeter. In this report, the principle of TES microcalorimeter, the measurement experiment using TES in JAEA, and the simulated calculation using the EGS5 code system are summarized.
Enomoto, Kazuyuki; Takahashi, Shuichi; Rohani, R.; Maekawa, Yasunari
Journal of Membrane Science, 415-416, p.36 - 41, 2012/10
Polymer electrolyte membranes (PEM) consisting of ion conducting alkylsulfonic acid and hydroxyl groups were successfully synthesized by radiation-induced graft polymerization of vinyl acetate (VAc) into a poly(ethylene--tetrafluoroethylene) (ETFE) film, followed by alkylsulfonation with 1,3-propanesulfone. The prepared PEM showed higher conductivity under 30% relative humidity at 80C than that of the conventional poly(styrenesulfonic acid)-grafted ETFE. Furthermore, the prepared PEM also showed better mechanical properties than those of Nafion. Thus, the PEM with hydroxyl groups possesses sufficient mechanical and electrochemical properties, required for a fuel cell, operating at a high temperature and low humidity.
Taguchi, Yasujiro*; Sakai, Hideaki*; Okuyama, Daisuke*; Ishiwata, Shintaro*; Fujioka, Jun*; Fukuda, Tatsuo; Hashizume, Daisuke*; Kagawa, Fumitaka*; Takahashi, Yoichiro*; Shimano, Ryo*; et al.
Physica B; Condensed Matter, 407(11), p.1685 - 1688, 2012/06
Xianglian*; Sakuma, Takashi*; Mohapatra, S. R.*; Uehara, Hiroyuki*; Takahashi, Haruyuki*; Kamishima, Osamu*; Igawa, Naoki
Molecular Simulation, 38(5), p.448 - 451, 2012/04
Diffuse neutron scattering measurements have been performed on powder PbTe at 10 and 294 K. Oscillatory diffuse scattering intensity is clearly observed at 294 K. Oscillatory form of the diffuse neutron scattering intensity for PbTe was explained on inclusion of correlation effects among thermal displacements of atoms. From the values of correlation effects and Debye-Waller temperature parameter, force constants among the first nearest neighboring atoms was calculated, = 215 eV/nm, and the second ones were =108 eV/nm and = 144 eV/nm at 294 K.
Krogstrup, P.*; Morten Hannibal, M.*; Hu, W.; Kozu, Miwa*; Nakata, Yuka*; Nygard, J.*; Takahashi, Masamitsu; Feidenhans'l, R.*
Applied Physics Letters, 100(9), p.093103_1 - 093103_4, 2012/02
Kinase, Sakae; Mohammadi, A.; Takahashi, Masa; Saito, Kimiaki; Zankl, M.*; Kramer, R.*
Radiation Protection Dosimetry, 146(1-3), p.191 - 194, 2011/07
Takahashi, Koji; Kajiwara, Ken; Oda, Yasuhisa; Kasugai, Atsushi; Kobayashi, Noriyuki*; Sakamoto, Keishi; Doane, J.*; Olstad, R.*; Henderson, M.*
Review of Scientific Instruments, 82(6), p.063506_1 - 063506_7, 2011/06
High power, long pulse millimeter (mm) wave experiments of the RF test stand (RFTS) of JAEA were performed. The system consists of a 1 MW/170 GHz gyrotron, a long and short distance transmission line (TL) and an equatorial launcher (EL) mock-up. The RFTS has an ITER-relevant configuration, i.e., that is consisted by a 1 MW-170 GHz gyrotron, mm wave TL and EL mock-up. The TL is composed of a matching optics unit, evacuated circular corrugated waveguides, 6 miter bends, an in-line waveguide switch, an isolation valve. The Gaussian-like beam radiation with the steering capability of 20-40 from the EL mock-up was also successfully proved. The high power long pulse power transmission test was conducted with the metallic load replaced by the EL mock-up, and the transmission of 1 MW/800 s and 0.5 MW/1000 sec were successfully demonstrated with no arcing and no damages. The transmission efficiency of the TL was 96%. The results prove the feasibility of the ITER electron cyclotron heating and current drive system.
Sakuma, Takashi*; Xianglian*; Shimizu, Norifumi*; Mohapatra, S. R.*; Isozaki, Nobuhiro*; Uehara, Hiroyuki*; Takahashi, Haruyuki*; Basar, K.*; Igawa, Naoki; Kamishima, Osamu*
Solid State Ionics, 192(1), p.54 - 57, 2011/06
Diffuse neutron scattering measurements have been performed on powder KBr. The oscillatory scheme of the diffuse scattering intensity is explained by the values of correlation effects among thermal displacements of 1st, 2nd and 3rd nearest neighboring atoms which are almost the same as those in other ionic crystals. Force constants among 1st, 2nd and 3rd nearest neighboring atoms are obtained from the correlation effects at 90 K are 0.83 eV/, 0.50 eV/ and 0.41 eV/, respectively.