Abe, Yuta; Tsuchikawa, Yusuke; Kai, Tetsuya; Matsumoto, Yoshihiro*; Parker, J. D.*; Shinohara, Takenao; Oishi, Yuji*; Kamiyama, Takashi*; Nagae, Yuji; Sato, Ikken
Proceedings of 2020 International Conference on Nuclear Engineering (ICONE 2020) (Internet), 6 Pages, 2020/08
Kawamura, Shunsuke; Naoe, Takashi; Ikeda, Tsubasa*; Tanaka, Nobuatsu*; Futakawa, Masatoshi
Advanced Experimental Mechanics, 4, p.33 - 37, 2019/08
A mercury enclosure vessel made of stainless steel is used as a spallation target in the pulsed spallation neutron source at J-PARC. It is severely damaged by the cavitation induced with pressure waves in association with the pulsed proton beam injection. A double-walled structure with a narrow mercury channel was adopted in the front end of the target vessel to reduce the cavitation damage. It has been experimentally demonstrated that the cavitation damage could be mitigated in the narrow channel but its mechanism has been unclarified yet. In this study, we investigated the cavitation from growing to collapsing through visualizing the spark-induced cavitation bubbles under flow field using a high-speed video camera. Furthermore, we measured the wall vibration due to the cavitation bubble collapse with changing flow velocity parametrically. It was found that the microjet collided perpendicular to the wall in the stagnant flow condition while it collided with an inclined angle from the perpendicular direction, suggesting that the collision pressure on the wall was reduced by flowing.
Sugimoto, Taro*; Saito, Shimpei*; Kaneko, Akiko*; Abe, Yutaka*; Uchibori, Akihiro; Ohshima, Hiroyuki
Proceedings of 26th International Conference on Nuclear Engineering (ICONE-26) (Internet), 7 Pages, 2018/07
A computational fluid dynamics code for a sodium-water reaction phenomenon in a steam generator of sodium-cooled fast reactors has been developed. In order to provide the data for validation of this code, the visualization experiment on liquid droplet entrainment in the high-pressure air jet submerged in the water pool was carried out. The experiment successfully elucidated the behavior, such as atomization of the relatively large diameter liquid droplet generated from the gas-liquid interface.
Aoyagi, Kazuhei; Chen, Y.*; Sakurai, Akitaka; Ishii, Eiichi; Ishida, Tsuyoshi*
JAEA-Research 2017-014, 49 Pages, 2018/01
In this research, we performed the resin injection experiment at the 350 m gallery of the Horonobe Underground Research Laboratory in order to identify the three dimensional distribution of fractures induced around the gallery owing to excavation. To this end, the low viscosity resin mixed with a fluorescent substance was developed and applied to the in situ resin injection experiment. As a result, the resin was successfully penetrated into the fractures around the gallery without disturbing their situation and then fixed within them. After the experiment, the rock cores around the injection borehole were drilled for the observation. The observation under ultraviolet light revealed that the extent of the development of fractures was about 0.9 m into the borehole wall. In addition, the aperture of the fractures distributed within 0.3 m from the gallery wall was ranged 1 to 2 mm, and that distributed from 0.3 to 0.9 m was less than 1 mm. On the other hand, in the borehole televiewer (BTV) survey, only one fracture within 0.2 m from the wall could be detected owing to the resolution of the survey system. Thus, it is expected that the BTV survey underestimate the extent of the development of fractures.
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.
Sakurai, Daisuke; Saeki, Osamu*; Carr, H.*; Wu, H.-Y.*; Yamamoto, Takahiro*; Duke, D.*; Takahashi, Shigeo*
IEEE Transactions on Visualization and Computer Graphics, 22(1), p.945 - 954, 2016/01
Scalar topology in the form of Morse theory has provided computational tools that analyze and visualize data from scientific and engineering tasks. Contracting isocontours to single points encapsulates variations in isocontour connectivity in the Reeb graph. For multivariate data, isocontours generalize to fibers inverse images of points in the range, and this area is therefore known as fiber topology. However, fiber topology is less fully developed than Morse theory, and current efforts rely on manual visualizations. This paper therefore shows how to accelerate and semi-automate this task through an interface for visualizing fiber singularities of multivariate functions : . This interface exploits existing conventions of fiber topology, but also introduces a 3D view based on the extension of Reeb graphs to Reeb spaces. Validation of the interface is performed by assessing whether the interface supports the mathematical workflow both of experts and of less experienced mathematicians.
Kato, Yuki; Yoshida, Hiroyuki; Yokoyama, Ryotaro*; Kanagawa, Tetsuya*; Kaneko, Akiko*; Monji, Hideaki*; Abe, Yutaka*
Proceedings of 23rd International Conference on Nuclear Engineering (ICONE-23) (DVD-ROM), 8 Pages, 2015/05
JAEA-Data/Code 2014-027, 32 Pages, 2015/02
A suite of software tools has been developed to facilitate the development of apparatus using a radiation transport simulation code PHITS by enabling 4D visualization (3D space and time) and quantitative analysis of so-called dieaway plots. To deliver useable tools as soon as possible, the existing software was utilized as much as possible; ParaView will be used for the 4D visualization of the results, whereas the analyses of dieaway plots will be done with ROOT toolkit with a tool named "diana". To enable 4D visualization using ParaView, a suite of tools (angel2vtk, DispDCAS1, CamPos) have been developed for the conversion of the data format to the one which can be read from ParaView and to ease the visualization.
Kawamura, Takuma; Idomura, Yasuhiro; Miyamura, Hiroko; Takemiya, Hiroshi; Sakamoto, Naohisa*; Koyamada, Koji*
Visualization and Data Analysis 2015 (Proceedings of SPIE Vol.9397) (Internet), p.93970S_1 - 93970S_8, 2015/02
In this paper, we propose a novel remote visualization system based on particle-based volume rendering (PBVR), which enables interactive analyses of extreme scale volume data located on remote computing systems. The remote PBVR system consists of Server, which generates particles for rendering, and Client, which processes volume rendering, and the particle data size becomes significantly smaller than the original volume data. Depending on network bandwidth, the level of detail of images is flexibly controlled to attain high frame rates. Server is highly parallelized on various parallel platforms with hybrid programing model. The mapping process is accelerated by two orders of magnitudes compared with a single CPU. The structured and unstructured volume data with 100 millions of cells is processed within a few seconds. Compared with commodity Client/Server visualization tools, the total processing cost is dramatically reduced by using proposed system.
Hoshi, Yoshiyuki; Kume, Etsuo
JAERI-Data/Code 2005-010, 48 Pages, 2005/09
In scientific and engineering calculations, recently, computational sizes and amounts of calculated results have been increased rapidly due to speedup of computers and increase in memory size. Post processing or visualization of a huge amount of numerical data plays a very important role for understanding the meaning of the data. Computational loads for visualization of large-scale data are still heavy even for graphic computers. Processing speeds for visualization of large-scale data are measured using general-purpose visualization software on graphic computers in JAERI. A guideline is summarized in this report to choose appropriate graphic computers according to the size of the data.
JAERI-Research 2005-016, 127 Pages, 2005/08
no abstracts in English
Suzuki, Yoshio; Matsumoto, Nobuko*; Yamagishi, Nobuhiro*; Arakawa, Takuya*; Kuraishi, Hideaki*
JAERI-Data/Code 2004-013, 163 Pages, 2005/02
The Center for Promotion of Computational Science and Engineering of the Japan Atomic Energy Research Institute has carried out the ITBL (Information-Technology Based Laboratory) project which is one of e-Japan priority policy programs. AVS/ITBL is the visualization tool which has been developed aiming at realizing the efficient visualization in the ITBL environment. This visualization tool is one of the tools of ITBL infrastructure software and operates in cooperation with AVS/Express. In this paper, utilization of AVS/ITBL to the numerical environmental system, which is one of the applications in ITBL project, is presented. And the outline of the operation in this utilization is indicated.
JAERI-Data/Code 2004-009, 31 Pages, 2004/12
In recent years, visualization techniques have become more and more important in various fields. Especially in scientific fields, a large amount of numerical output data crucially needs to be changed into visualized form, because computations have grown to larger and larger scales as well as have become more complicated, so that computed results must be intuitively comprehensible by using various visualization techniques like 3D or stereo image construction. In the visualization room in the ITBL building, a 3-screen Virtual Reality system, a Portable Virtual Reality system, a Mixed Reality system, and Visualization tools like alchemy etc. are installed for the above-mentioned use. These devices enable us to easily change numerical data into visualized images of a virtual reality world with the use of eye-glasses or a head-mount-display device. This article describes the visualization environment in the ITBL building, it's use, and the tasks to be solved.
Takeshima, Yuriko; Suzuki, Yoshio*; Matsumoto, Nobuko*; Sai, Kazunori*; Nakajima, Norihiro
Proceedings of 4th International Symposium on Advanced Fluid Information and Transdiciplinary Fluid Integration (AFI/TFI 2004), p.157 - 158, 2004/11
The Information-Technology-Based Laboratory (ITBL) project aims to construct a virtual research environment which shares intellectual resources such as the super computers by the grid computing, softwares and data in Japan and supports joint researches at a distance. In the project, two visualization systems: the PATRAS/ITBL and the AVS/ITBL have been developed. The feature of the PATRAS/ITBL is the collaborative, real-time visualization of data resulting from an execution of numerical simulations. The AVS/ITBL visualization system enables remote postprocessing visualization of any data stored on any supercomputer located in the ITBL network. The global structure and technologies of these systems are presented.
Takeshima, Yuriko; Takahashi, Shigeo*; Fujishiro, Issei*; Nielson, G. M.*
Proceedings of IEEE Visualization 2004 (VIS 2004) (CD-ROM), 2 Pages, 2004/10
no abstracts in English
VizJournal, (11), 5 Pages, 2004/06
This paper explains the neutron radiography thermal-hydraulic measurement technique, especialy visualization technique, which was developed at Japan Atomic Energry Research Institute. Observation of large and fine-mesh data obtained by the new measurement technology is important from a research point of view. We developed the advanced visualization software which puts into practice effective observation by using new visualization methods, and we made the vizualization of phenomena possible by using VR and/or animation displays etc. by this system. Especially in this paper, the visualization techniques which were used in a prize-winning work of the "Visual Sience Festa 2003" by NIKKEI SCIENCE as easy to read for a general reader as possible by using many figures and movies.
Purazuma, Kaku Yugo Gakkai-Shi, 80(5), p.378 - 381, 2004/05
Progress of large scale scientific simulation environment in JAERI is briefly described. The expansion of fusion simulation science have been played a key role in the increasing performances of super computers and computer network system in JAERI. Both scalar parallel and vector parallel computer systems are now working in Naka and Tokai sites respectively and, particle and fluid simulation codes developed under the fusion simulation project, NEXT, are running on each system. The storage grid system has been also successfully developed for the effective visualization analysis by remote users. Fusion research is going to enter the new phase of ITER, and the need for the super computer system with higher performance are increasing more than as ever along with the development of reliable simulation models.
Masuko, Kenji*; Watanabe, Ritsuko; Kume, Etsuo
JAERI-Data/Code 2004-005, 72 Pages, 2004/03
no abstracts in English
JAERI-Conf 2004-003, 62 Pages, 2004/03
no abstracts in English
JAERI-Conf 2004-003, p.52 - 55, 2004/03
no abstracts in English