Time evolution calculation of muon catalysed fusion; Emission of recycling muons from a two-layer hydrogen film

Yamashita, Takuma*; Okutsu, Kenichi*; Kino, Yasushi*; Nakashima, Ryota*; Miyashita, Konan*; Yasuda, Kazuhiro*; Okada, Shinji*; Sato, Motoyasu*; Oka, Toshitaka; Kawamura, Naritoshi*; et al.

Fusion Engineering and Design, 169, p.112580_1 - 112580_5, 2021/08

https://doi.org/10.1016/j.fusengdes.2021.112580

A muon () having 207 times larger mass of electron and the same charge as the electron has been known to catalyze a nuclear fusion between deuteron (d) and triton (t). These two nuclei are bound by and form a muonic hydrogen molecular ion, dt. Due to the short inter-nuclear distance of dt, the nuclear fusion, d +t + n + 17.6 MeV, occurs inside the molecule. This reaction is called muon catalyzed fusion (CF). Recently, the interest on CF is renewed from the viewpoint of applications, such as a source of high-resolution muon beam and mono-energetic neutron beam. In this work, we report a time evolution calculation of CF in a two-layered hydrogen isotope target.

Visualization in response analyses for a nuclear power plant

Nakajima, Norihiro; Nishida, Akemi; Miyamura, Hiroko; Iigaki, Kazuhiko; Sawa, Kazuhiro

Kashika Joho Gakkai-Shi (USB Flash Drive), 36(Suppl.2), 4 Pages, 2016/10

Since nuclear power plants have dimensions approximately 100m and their structures are an assembly made up of over 10 million components, it is not convenient to experimentally analyze its behavior under strong loads of earthquakes, due to the complexity and hugeness of plants. The proposed system performs numerical simulations to evaluate the behaviors of an assembly like a nuclear facility. The paper discusses how to carry out visual analysis for assembly such as nuclear power plants. In a result discussion, a numerical experiment was carried out with a numerical model of High Temperature engineering Test Reactor of Japan Atomic Energy Agency and its result was compared with observed data. A good corresponding among them was obtained as a structural analysis of an assembly by using visualization. As a conclusion, a visual analytics methodology for assembly is discussed.

Seismic response simulation of High-Temperature Engineering Test Reactor building against 2011 Tohoku earthquake

Nishida, Akemi; Nakajima, Norihiro; Kawakami, Yoshiaki; Iigaki, Kazuhiko; Sawa, Kazuhiro

Proceedings of 23rd International Conference on Nuclear Engineering (ICONE-23) (DVD-ROM), 7 Pages, 2015/05

The R&D on the three dimensional vibration simulation technologies for a nuclear facility is one of missions of Center for Computational Science and e-Systems, Japan Atomic Energy Agency. Until now, three dimensional building and equipment models of HTTR (High Temperature Engineering Test Reactor) have been constructed and been performed validation of the models by comparison with seismic observed records. In this report, the results obtained by seismic observation simulation on the Tohoku earthquake occurred in the 3/11/2011 using three dimensional models of the HTTR building are shown. The simulation results show good agreement with the real observation data.

Structural analysis for assembly by integrating parts

Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Okada, Tatsuo*; Tsuruta, Osamu*; Sawa, Kazuhiro; Iigaki, Kazuhiko

Proceedings of 22nd International Conference on Nuclear Engineering (ICONE-22) (DVD-ROM), 9 Pages, 2014/07

https://doi.org/10.1115/ICONE22-30251

Almost all industrial products are assembled from multiple parts. A nuclear facility is a large structure consisting of more than 10 million components. This paper discusses a method to analyze an assembly by gathering data on its component parts. Gathered data on component may identify ill conditioned meshes for connecting surfaces between components. These ill meshes are typified by nodal point disagreement in finite element discretization. A technique to resolve inconsistencies in data among the components is developed. By using this technique, structural analysis for an assembly can be carried out, and results can be obtained by the use of supercomputers, such as the K computer. Numerical results are discussed for components of the High Temperature Engineering Test Reactor.

A Quake-proof analysis for a plant as an assembly in the next generation

Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Okada, Tatsuo; Tsuruta, Osamu; Sawa, Kazuhiro; Iigaki, Kazuhiko

Tabo Kikai, 42(5), p.332 - 338, 2014/05

K computer is one of the highest performance computers in the world. This paper discusses one of R&D issues in K computer national project. Industrial products are an artifact, which are assembly consisting of simple components more than at least two regardless of the big products and small products. In the nuclear industry, the facilities are large structures consisting of over 10 millions of components, since they are engaged with the highest technology and for safety sake. This paper introduces a method to analyze an assembly by gathering its components data. In the manner of gathering components data, it is raised many issues to concern among components. It is developed a technique to solve the inconsistent data among the components. By using this technique, a structural analysis for an assembly is done by using K computer. Numerical results are presented in the case of analysis for High Temperature engineering Test Reactor's components.

Assembly structure analysis system

Nakajima, Norihiro; Nishida, Akemi; Matsubara, Hitoshi*; Hazama, Osamu*; Suzuki, Yoshio; Sawa, Kazuhiro; Iigaki, Kazuhiko

Transactions of the 22nd International Conference on Structural Mechanics in Reactor Technology (SMiRT-22) (CD-ROM), 10 Pages, 2013/08

It is not convenient to experimentally analyze its behavior under strong loads of earthquakes, since the facility is extremely huge and complex. The proposed system performs numerical simulations to evaluate the behaviors of an assembly like a nuclear facility. This system projects the components of an assembly onto both/either a distributed and/or a parallel computing environment in order to conduct a simulation of the behavior of an assembly such as a nuclear facility. In a result discussion, a numerical experiment was carried out with a cantilever model and its result was compared with theoretical data. A good corresponding among them was obtained as a structural analysis of an assembly by using a parallel computer. As a conclusion, a suggested methodology has shown to calculate a behavior of an assembly with High Temperature engineering Test Reactor.

Enhancement of the superconducting critical temperature in BiSrCaCuO by controlling disorder outside CuO planes

Hobo, Hiroaki*; Ishida, Shigeyuki*; Fujita, Kazuhiro*; Ishikado, Motoyuki; Kojima, Kenji*; Eisaki, Hiroshi*; Uchida, Shinichi*

Physical Review B, 79(6), p.064507_1 - 064507_6, 2009/02

https://doi.org/10.1103/PhysRevB.79.064507

We investigate the effect of disorder at various lattice sites outside the CuO plane on the superconducting critical temperature of the cuprate superconductor BiSrCaCuO (Bi2212). The most effective disorder turns out to be that at the Sr site in the neighboring blocks, which contain apical-oxygen atoms.

JOYO MK-III Performance test report; Blower start-up test (PT-303), Power-increase test (PT-301), Rated power operation test (PT-302)

Oyama, Kazuhiro; Kawahara, Hirotaka; Ishida, Koichi; Ariyoshi, Masahiko; Isozaki, Kazunori; Sugaya, Kazushi*; Fukami, Akihiro*

JNC TN9410 2005-006, 121 Pages, 2005/03

JNC-TN9410-2005-006.pdf:10.81MB

In the MK-III performance test, the experimental fast reactor JOYO raised the reactor thermal power gradually with about 20%, 50%, 75%, 90%, and 100% (140MWt), and reached 140MWt which are the full power of a MK-III reactor core on October 28, 2003. Then, continuation operation beyond full power 100 hour was attained. This report summarized the result of power-up test , full power continuation operation test, blower start-up test.The outline is as follows.(1)From the standby state (system temperature of 250degree), the usual power-up operation (an power-up rate ;about 5MWt/20min, a power is held for about 10 minutes every 5MWt) attained the reactor thermal full power (140MWt) gradually on October 28,2004. Moreover, it checked that each part temperature and flow were less than alarm setting values on each power level.(2)The reactor thermal power was made into the parameter, a series of operations about the blower start-up, and the influence which it has on coolant temperature was checked. As a result, the optimal reactor thermal power which starts up the blower from a natural ventilation cooling state was set to about 18 MWt, and the starting procedure was made into the method(order of 1A-2A-1B-2B) which starts four sets of the one blower at a time one by one.(3)It checked that reactor shutdown operation by two control-rod simultaneous insertion at 35MWt, and it could carry out with time margin with a series of sufficient operations of resulting from control rod insertion in the blower shutdown. By adopting this reactor shutdown operation method, operation of an operation stuff was mitigated and it checked that plant characteristics also improved.(4)The reactor full power was reached on November 14. Continuation operation beyond full power 100 hour was attained after that till on November 20, 10:30. The data of each part of a plant was acquired at intervals of 24 hours, and it checked that it was less than an alarm setting value.

Advanced control scenario of high-performance steady-state operation for JT-60 superconducting tokamak

Tamai, Hiroshi; Kurita, Genichi; Matsukawa, Makoto; Urata, Kazuhiro*; Sakurai, Shinji; Tsuchiya, Katsuhiko; Morioka, Atsuhiko; Miura, Yushi; Kizu, Kaname; Kamada, Yutaka; et al.

Plasma Science and Technology, 6(3), p.2281 - 2285, 2004/06

https://doi.org/10.1088/1009-0630/6/3/003

High performance steady-state operation for JT-60SC are evaluated by the TOPICS analysis. 5 and bootstrap current fraction 86% is kept steady at I=1.5 MA, B=2 T by neutral beam power of 11 MW. The ERATO-J analysis shows that the external-kink mode with multiple toroidal mode numbers of n=1 and n=2 is stable at 5.5 at the average ratio of conducting wall radius to plasma minor radius of about 1.2 with the wall stabilisation effect. Resistive wall modes, induced by a close location of the wall to plasma, is expected to be suppressed by the active feedback stabilisation with a set of non-axisymmetric field coils behind the stabilising plates. Further optimisation for the high- accessibility by the plasma shaping is performed with the TOSCA analysis. The plasma shaping factor defined as S=(I/aB)q and strongly correlated to the plasma elongation and triangularity, is scanned from 4 to 6, which extends the availability of current and pressure profile control for the high performance plasma operation.

Advanced fusion technologies developed for JT-60 superconducting Tokamak

Sakasai, Akira; Ishida, Shinichi; Matsukawa, Makoto; Akino, Noboru; Ando, Toshinari*; Arai, Takashi; Ezato, Koichiro; Hamada, Kazuya; Ichige, Hisashi; Isono, Takaaki; et al.

Nuclear Fusion, 44(2), p.329 - 334, 2004/02

https://doi.org/10.1088/0029-5515/44/2/015

no abstracts in English