Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Nishida, Akemi; Araya, Fumimasa; Kushida, Noriyuki; Kondo, Makoto; Sakai, Michiya*; Shiogama, Yuzo*
Progress in Nuclear Science and Technology (Internet), 2, p.576 - 581, 2011/10
Design evaluation of nuclear facilities would be facilitated by a numerical evaluation system that can evaluate both global and local behaviors under severe seismic loading. A critical part of such a system is the numerical model describing the dynamic physical interactions among component connections, called the elastic-plastic connection model. Here we propose such a model and use it to simulate dynamic interactions using real earthquake and plant data from the High Temperature Engineering Test Reactor (HTTR) of the JAEA. We focus on joints connecting the component supports and the building walls, which generally involve fixed/pinned boundary conditions. The results confirmed a reduction in the vibration response and a change in the natural frequencies of individual components under large virtual earthquake loading, which are considered to have resulted from dynamic interactions between the joints connecting the component supports and the building walls.
Yamada, Tomonori; Kushida, Noriyuki; Araya, Fumimasa; Nishida, Akemi; Nakajima, Norihiro
Key Engineering Materials, 452-453, p.701 - 704, 2011/01
The paper describes a component-wise meshing approach and bonding strategy on the interface of components. In order to assemble component-wise meshes, the penalty method is introduced not only to constrain the displacements, but also to introduce classical spring connection on the joint interface. The convergence performance of an iterative solver with penalty method is investigated and the detailed component-wise distributed computation scheme is described with numerical examples.
Kino, Chiaki; Tatekawa, Takayuki; Teshima, Naoya; Kim, G.; Suzuki, Yoshio; Araya, Fumimasa; Nishida, Akemi; Takemiya, Hiroshi
Proceedings of Joint International Conference of 7th Supercomputing in Nuclear Application and 3rd Monte Carlo (SNA + MC 2010) (USB Flash Drive), 4 Pages, 2010/10
In the present study, we have developed a new control system for application integration with the fault-tolerant API (FT-API). The system treats an application as a task which consists of one job and multiple file transfer. Firstly, each task designates a computer to submit a job using a scheduler associated to the job. Secondly, all files which are necessary to execute the job are gathered in the computer using FT-API for file transfer. Finally, the job is submitted using FT-API for job execution. If the computer is outage, the task designates a new computer, gathers necessary files and submits a new job. Each scheduler, file transfer and job condition can be flexibly defined in XML. This time, we applied the system to fluid-structure interaction analysis simulation. The result indicates that the system enables a user to easily execute multi-scale and multi-physics simulation using application integration.
Nishida, Akemi; Araya, Fumimasa; Kushida, Noriyuki; Kondo, Makoto; Sakai, Michiya*; Shiogama, Yuzo*
Proceedings of Joint International Conference of 7th Supercomputing in Nuclear Application and 3rd Monte Carlo (SNA + MC 2010) (USB Flash Drive), 6 Pages, 2010/10
The objective of this research is to contribute to the seismic design evaluation of nuclear facilities through the construction of a numerical evaluation system which is able to evaluate both global and local behaviors of facilities under severe seismic events. As one of the technology components to realize this objective, we are developing a physical model describing the dynamic interaction characteristics of component connections, called as the elastic-plastic connection model. We focused on the joints of the support structures of the component and the building in nuclear plants which generally designed as fixed/pinned boundaries, and tried to consider their dynamic interaction effects. In this paper, we show the proposal of the elastic-plastic connection model and the application of the model to a numerical simulation using a real plant data. The precision of the model was optimized by adjusting its parameters using the data obtained in the experiment.
Yamada, Tomonori; Araya, Fumimasa
High Performance Computing on Vector Systems 2009, p.223 - 232, 2009/11
Kim, G.; Suzuki, Yoshio; Teshima, Naoya; Nishida, Akemi; Yamada, Tomonori; Araya, Fumimasa; Takemiya, Hiroshi; Nakajima, Norihiro; Kondo, Makoto
Proceedings of 1st International Conference on Parallel, Distributed and Grid Computing for Engineering (PARENG 2009) (CD-ROM), 12 Pages, 2009/04
Nishida, Akemi; Araya, Fumimasa; Yamada, Tomonori; Kushida, Noriyuki; Takemiya, Hiroshi; Nakajima, Norihiro
Anzen Kenkyu Foramu 2009 Shiryoshu, p.25 - 29, 2009/02
The development of a vibration simulator has been planned for used in a full-scale nuclear power station; this simulator will implement the latest computational technologies and will allow comparisons to be made among the conventional spring-mass models and the actually observed data obtained from experiment and practice. This simulator will be used for evaluating the conservativeness of conventional models and the fragility of components through a seismic PSA (probabilistic safety assessment). This simulator will be used for analyzing the seismic responses of the entire nuclear facility by modeling each component independently. The numerical capability of the simulator has already been confirmed; presently, the accuracy of the dynamic response results is being investigated by means of a comparison with the recorded data of an actual plant system.
Suzuki, Yoshio; Nishida, Akemi; Araya, Fumimasa; Kushida, Noriyuki; Akutsu, Taku; Teshima, Naoya; Nakajima, Kohei; Kondo, Makoto; Hayashi, Sachiko; Aoyagi, Tetsuo; et al.
Journal of Power and Energy Systems (Internet), 3(1), p.60 - 71, 2009/00
Center for computational science and e-systems of Japan Atomic Energy Agency is carrying out R&D in the area of extra large-scale simulation technologies for solving nuclear plant structures in its entirety. Specifically, we focus on establishing a virtual plant vibration simulator on inter-connected supercomputers intended for seismic response analysis of a whole nuclear plant. The simulation of a whole plant is a very difficult task because an extremely large dataset must be processed. To overcome this difficulty, we have proposed and implemented a necessary simulation framework and computing platform. The computing platform enables an extra large-scale whole nuclear plant simulation to be carried out on a grid computing platform ITBL-IS and AEGIS. The simulation framework based on the computing platform has been applied to a linear elastic analysis of the reactor pressure vessel and cooling systems of the nuclear research facility, HTTR.
Nakajima, Norihiro; Araya, Fumimasa; Nishida, Akemi; Suzuki, Yoshio; Ida, Masato; Yamada, Tomonori; Kushida, Noriyuki; Kim, G.; Kino, Chiaki; Takemiya, Hiroshi
Proceedings of International Symposium on Structures under Earthquake, Impact, and Blast Loading 2008, p.119 - 123, 2008/10
Japan is so said an energy consumption country of the fourth place world, but the energy resources such as petroleum, the natural gas are poor and depend on import for the most, and stable supply becomes a big problem. For the greenhouse gas restraint, the promotion of the energy saving is featured. A nuclear power plant for commerce in Japan has been started in 1966. The supply occupies about 30 percent of the now Japanese electricity generating. Due to the nature of Japan, earthquake proof is an important subject for social infrastructure operation. To encourage its proofing, many approaches have been applied into many infrastructures, not only computational approach. A computational science approach for earthquake proof is suggested with FIESTA(Finite Element Structural analysis for Assembly), a large scale simulation. A methodology is discussed from the point of view of impact and blast loadings. Examples of loadings in the nuclear engineering are introduced.
)lti-monitoring (
)elf (
)nteraction (
)ondition in (
)ata (
)xplorer for ()valuation (
)rocessingNakajima, Norihiro; Araya, Fumimasa; Suzuki, Yoshio; Nishida, Akemi; Matsubara, Hitoshi; Nakajima, Kohei
Dai-27-Kai Nihon Shimyureshon Gakkai Taikai Happyo Rombunshu, p.511 - 514, 2008/06
A real space simulator for vibration table targeted to a nuclear power station has been proposed, which generates over tera-byte amount of calculated result. In order to analyze a huge size data, a data analyzer and data analyzing monitor system is suggested in this paper. A result of finite element analysis is examined by the system taking into account relation among neighboring elements' results. It is operated by multi-monitoring to view analyzing process. The system is implemented on a grid computing environment, AEGIS (atomic energy grid infrastructure) with coupling a large data visualization system.
Nakajima, Norihiro; Araya, Fumimasa; Nishida, Akemi; Suzuki, Yoshio; Kushida, Noriyuki; Yamada, Tomonori
Dai-57-Kai Riron Oyo Rikigaku Koenkai Koen Rombunshu, p.33 - 35, 2008/06
It has been disciplined to realize a simulation space, which can emulate real world in digital space, such as so named either virtual reality or virtual facility. In this paper, it is realized an assembly structural analysis for supplying one of the methodology to reproduce facilities in digital space. The first attempt of the assembly structural analysis is accomplished by finite element analysis by integrating parts of facilities. Since the assembly structural analysis requests massive calculation, grid computing was applied for the computational resource.
Suzuki, Yoshio; Nakajima, Norihiro; Araya, Fumimasa; Hazama, Osamu; Nishida, Akemi; Kushida, Noriyuki; Akutsu, Taku; Teshima, Naoya; Nakajima, Kohei; Kondo, Makoto; et al.
Proceedings of 16th International Conference on Nuclear Engineering (ICONE-16) (CD-ROM), 9 Pages, 2008/05
Nishida, Akemi; Araya, Fumimasa; Matsubara, Hitoshi; Hazama, Osamu; Nakajima, Norihiro
Anzen Kenkyu Foramu 2008 Sanko Shiryoshu, p.93 - 94, 2008/02
The development of a vibration simulator has been planned for used in a full-scale nuclear power station; this simulator will implement the latest computational technologies and will allow comparisons to be made among the conventional spring-mass models and the actually observed data obtained from experiment and practice. This simulator will be used for evaluating the conservativeness of conventional models and the fragility of components through a seismic PSA (probabilistic safety assessment). This simulator will be used for analyzing the seismic responses of the entire nuclear facility by modeling each component independently.
Hazama, Osamu; Kushida, Noriyuki; Matsubara, Hitoshi; Nishida, Akemi; Suzuki, Yoshio; Araya, Fumimasa; Aoyagi, Tetsuo; Nakajima, Norihiro; Kondo, Makoto
Proceedings of 9th MpCCI User Forum, p.118 - 124, 2008/00
In order to safely and stably supply energy by nuclear means, structural integrity and design standards of the plant including factors such as aging must be confirmed, and its future conditions must be predicted with high reliability. Although full-scale experimentations are favorable for acquiring necessary information and carrying out investigative studies of the nuclear structures, such experiments are for most cases physically and financially impossible. Our objective is to establish an integrated full-scale simulation framework for simulating and quantitatively investing the vibration behavior of nuclear power plant equipments under earthquakes.
Yamada, Tomonori; Araya, Fumimasa; Nishida, Akemi; Kushida, Noriyuki; Nakajima, Norihiro
Theoretical and Applied Mechanics Japan, 57, p.81 - 87, 2008/00
We realize a vibration table in an extended world for simulation, which is capable of emulating the real world's earthquake in digital space and brings concurrent experiments between real and digital one. In this paper, a methodology for reproducing facilities in an extended world is proposed through analysis of assembled structures, as well as introduction of the computing framework used.
Nishida, Akemi; Matsubara, Hitoshi; Tian, R.; Hazama, Osamu; Suzuki, Yoshio; Araya, Fumimasa; Nakajima, Norihiro; Tani, Masayuki; Kondo, Makoto
Nihon Genshiryoku Gakkai Wabun Rombunshi, 6(3), p.376 - 382, 2007/09
Unexpected accidents such as oil-tank fires caused by the earthquake and breakage of pipes of nuclear plants have occurred over the past several years. Higher reliability is thus now increasingly expected to maintain the safety of infrastructures. We have been intensely focused on the construction of an analysis system called the "three-dimensional virtual vibration testbed," which is a numerical simulation system for a nuclear plant which considers the interconnection of machines, pipes, buildings, and their foundations under real operating conditions. In this paper, the "part-wise analysis method" is proposed in which each structural component is treated independently and analyzed as an assembly structure. Further, the system configurations in a parallel distribution environment are described. This study shows one of the successful examples of the application of this method to a nuclear-plant cooling system that has tens of millions of degrees of freedom.
Hazama, Osamu; Araya, Fumimasa
Nihon Kikai Gakkai 2007-Nendo Nenji Taikai Koen Rombunshu, Vol.1, p.685 - 686, 2007/09
A new concept of double-wall-tube steam generator (SG) is being introduced and investigated as an innovative technology to realize next-generation sodium-cooled Fast Breeder Reactors (FBRs) for commercialization. This new concept is posing great challenges in the engineering design of a tubesheet which must bundle over 7000 double-wall tubes under severe mechanical and thermal loads. R&D efforts concerning the development of a feasible design and establishment of design-by-analysis methods for the new-concept tubesheet structure have been begun at JAEA. As a first step, an attempt at identifying the high stress locations and their magnitudes through large-scale numerical simulations using geometrical models in accord with reality are reported.
Tani, Masayuki; Nakajima, Norihiro; Nishida, Akemi; Suzuki, Yoshio; Matsubara, Hitoshi; Araya, Fumimasa; Kushida, Noriyuki; Hazama, Osamu; Kondo, Makoto; Kawasaki, Kozo
Proceedings of Joint International Topical Meeting on Mathematics & Computations and Supercomputing in Nuclear Applications (M&C+SNA 2007) (CD-ROM), 12 Pages, 2007/04
Nakajima, Norihiro; Araya, Fumimasa; Hirayama, Toshio
Genshiryoku eye, 52(10), p.22 - 34, 2006/10
no abstracts in English
Sugimoto, Jun*; Anoda, Yoshinari*; Araya, Fumimasa*; Yamaguchi, Toshio*; Sato, Yoshinori;
JNC TN1200 2004-002, 100 Pages, 2004/07
JNC-TN1200-2004-002.pdf:5.41MB
The second JAERI-JNC Joint Conference on Nuclear Safety Research was held on February 6, 2004 in Tokyo for those who are relevant to nuclear industries and regulatory organizations, and general public. The nuclear safety research has been conducted in both institutes according to the Five-Year Program for Nuclear Safety Research established periodically by the Nuclear Safety Commission (NSC) and needs from the regulatory organizations. The objectives of the conference are to present its recent results and to collect views and opinions from the participants for its future program through the discussion after each presentation and panel discussion on how to conduct efficiently the nuclear safety research in the New Organization. A total of 259 people participated in the conference mainly from the nuclear industries and regulatory organizations and the number was much larger than that in the last conference of 188.The conference consisted of presentations on the safety research results, a special lecture and a panel discussion. First, the overview of safety research results was presented from each institute. Then, the results in the field of nuclear installations,environmental adioactivity and radioactive waste were presented from each institute. Then, Dr. Higashi, the Nuclear Safety Commissioner, made a special lecture on the radiation protection from the high-level radioactive waste disposal. Finally, a panel discussion was conducted with the title of "how to conduct efficiently the nuclear safety research in the New Organization" chaired by Prof. Kimura, the chairperson of Standing Committee on Nuclear Safety Research under the NSC. The panelists from the regulatory organizations, nuclear industry, JAERI and JNC discussed the subject together with the participants on the floor.The panelists not from JAERI and JNC expressed their views and opinions on how to conduct efficiently the nuclear safety research in the New Organization that were valuable inputs for
