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Journal Articles

Spallation and fragmentation cross sections for 168 MeV/nucleon $$^{136}$$Xe ions on proton, deuteron, and carbon targets

Sun, X. H.*; Wang, H.*; Otsu, Hideaki*; Sakurai, Hiroyoshi*; Ahn, D. S.*; Aikawa, Masayuki*; Fukuda, Naoki*; Isobe, Tadaaki*; Kawakami, Shunsuke*; Koyama, Shumpei*; et al.

Physical Review C, 101(6), p.064623_1 - 064623_12, 2020/06

 Times Cited Count:2 Percentile:35.83(Physics, Nuclear)

The spallation and fragmentation reactions of $$^{136}$$Xe induced by proton, deuteron and carbon at 168 MeV/nucleon were studied at RIKEN Radioactive Isotope Beam Factory via the inverse kinematics technique. The cross sections of the lighter products are larger in the carbon-induced reactions due to the higher total kinetic energy of carbon. The energy dependence was investigated by comparing the newly obtained data with previous results obtained at higher reaction energies. The experimental data were compared with the results of SPACS, EPAX, PHITS and DEURACS calculations. These data serve as benchmarks for the model calculations.

Journal Articles

Investigation of error estimation method of observational data and comparison method between numerical and observational results toward V&V of seismic simulation

Suzuki, Yoshio; Kawakami, Yoshiaki*; Nakajima, Norihiro

Mechanical Engineering Reviews, 4(1), p.15-00525_1 - 15-00525_18, 2017/01

The method to estimate errors included in observational data and the method to compare numerical results with observational results are investigated toward the verification and validation (V&V) of a seismic simulation. For the method to estimate errors, it is found that errors are caused by the resolution, the linearity, the temperature coefficient for sensitivity, the temperature coefficient for zero shift, the transverse sensitivity, the seismometer property, the aliasing, and so on. Thus, it is needed to estimate errors individually for those factors and integrate them. For the method to compare numerical results with observational results, it is found that six methods have been mainly proposed in existing researches. Evaluating those methods using nine items, advantages and disadvantages for those methods are arranged. The method is not well established so that it is necessary to employ those methods by compensating disadvantages and/or to search for a solution to a novel method.

Journal Articles

An Illustration by the next generation numerical simulator for quake-proofing on the K

Nakajima, Norihiro; Suzuki, Yoshio; Miyamura, Hiroko; Nishida, Akemi; Kawakami, Yoshiaki; Guo, Z.; Tomiyama, Eiji*

Keisan Kogaku, 20(4), p.3338 - 3340, 2015/12

The issue 5 in the field 4 of "Monodukuri" in the HPCI strategy project is introduced. The title of the issue 5 is "research and development for the next-generation earthquake-resistant simulation of the large plants such as nuclear energy facilities". The illustration intends for a high temperature engineering examination research reactor. Implementation of FIESTA (Finite Element Analysis for Structure of Assembly) on K is described by reporting its efficiency and performance. To show a result of the numerical analysis, a visualization technique for the big data was described.

Journal Articles

Time domain response analysis for assembly by integrating components

Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Suzuki, Yoshio; Matsukawa, Keisuke*; Oshima, Masami*; Izuchi, Hisao*

Transactions of 23rd International Conference on Structural Mechanics in Reactor Technology (SMiRT-23) (USB Flash Drive), 10 Pages, 2015/08

The digital shaking table is introduced to carry out numerical experiments for the so called STRUCTURE of a petroleum plant. In numerical experiments, STRUCTURE was precisely modelled as it is designed and meshed into fine finite elements. The components of STRUCTURE were meshed one by one, and the code of a finite element analysis for structure of assembly gathered every meshed components to run time domain response analysis. Four waves are applied to the analysis to determine its behaviour. Four waves are namely as El Centro, Taft, Hachinohe, and Geiyo. The results of experiments are discussed by comparing accumulating data in the past. It is concluded to reconfirm the methodology of gathering meshed components and a finite element analysis for structure of assembly with the STRUCTURE.

Journal Articles

Analyses for designing objects in mechanical design

Nakajima, Norihiro; Miyamura, Hiroko; Kawakami, Yoshiaki; Kawamura, Takuma

Kashika Joho Gakkai-Shi, 35(Suppl.1), p.233 - 238, 2015/07

no abstracts in English

Journal Articles

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.

Journal Articles

Numerical modeling assistance system in finite element analysis for the structure of an assembly

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

Proceedings of 23rd International Conference on Nuclear Engineering (ICONE-23) (DVD-ROM), 5 Pages, 2015/05

A numerical analysis controlling and managing system is implemented on K, which controls the modelling process and data treating, although the manager only controls a structural analysis by finite element method. The modeling process is described by the list of function ID and its procedures in a data base. The manager executes the process by order in the list for simulation procedures. The manager controls the intention of an analysis by changing the analytical process one to another. Experiments were carried out with static and dynamic analyses.

Journal Articles

Development of numerical modeling assistance system for finite element analysis

Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Suzuki, Yoshio

Nihon Kikai Gakkai Dai-24-Kai Sekkei Kogaku, Shisutemu Bumon Koenkai Koen Rombunshu (USB Flash Drive), 9 Pages, 2014/09

In this paper, a numerical analysis's controlling and managing system is suggested, which controls the modelling process and data treating for structural robustness, although a numerical analysis's manager only controls a structural analysis by finite element method. The modeling process is described by the list of function ID and its procedures in a data base. The analytical modeling manager executes the process by order of the lists for simulation procedures. The manager controls the intention of an analysis by changing the analytical process one to another. Modeling process was experimentally found that may subject to the intention of designing index. In the numerical experiments, K, supercomputer is utilized by using parallel computing resource with the controlling and managing system.

Journal Articles

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

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.

Journal Articles

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.

Journal Articles

The Japanese approach to developing clay-based repository concepts; An Example of design studies for the assessment of sealing strategies

Sugita, Yutaka; Fujita, Tomo; Takahashi, Yoshiaki*; Kawakami, Susumu; Umeki, Hiroyuki; Yui, Mikazu; Uragami, Manabu*; Kitayama, Kazumi*

Physics and Chemistry of the Earth, 32(1-7), p.32 - 41, 2007/00

 Times Cited Count:6 Percentile:22.71(Geosciences, Multidisciplinary)

The H12 repository concept for vitrified high-level radioactive waste was developed based on a multi-barrier system with the emphasis on robust engineered barrier performance to ensure its feasibility for a wide range of geological conditions typically observed in Japan. The buffer is clay-based and plays a very important role in the engineered barrier system (EBS). The decision to use a volunteer siting process requires maximum flexibility of the repository concept to allow it to be adapted to potential sites and hence a wide range of variants of the basic H12 repository design has been developed. In order to evaluate the feasibility and the applicability of different repository options to specific siting environments, NUMO has established a set of "design factors" which classify the aspects that need to be considered when evaluating the pros and cons of different repository options. A Na-type bentonite from Japan is used as the reference material for all clay-based repository components (buffer, backfill, clay plug, etc.). The characteristics of this bentonite (thermal, mechanical, chemical, hydraulic) have been examined with consideration of various practical constraints (limitation on the repository footprint, the influence of saline water, the interaction of hyperalkaline leachates and practical working environment, etc.). Clay-based seals, which close off the tunnels after emplacement of the EBS, may also be key components for assessment of the repository. Full analyses considering all engineered barrier components (buffer, backfill, clay plug, concrete lining, tunnel, concrete plug, host rock) that may be used in a repository will be an essential future task. As a first step towards this goal, a numerical analysis focusing on hydraulic behaviour at the intersections of the disposal tunnels and the main tunnel is presented to illustrate how the design requirements of clay-based seals can be determined.

JAEA Reports

Discussion on sealing performance required to disposal system; Hydraulic analysis considering intersections of tunnels

Sugita, Yutaka*; Fujita, Tomo; Takahashi, Yoshiaki*; Kawakami, Susumu; Umeki, Hiroyuki; Yui, Mikazu; Uragami, Manabu*

JNC TN8400 2005-016, 49 Pages, 2005/09

JNC-TN8400-2005-016.pdf:5.45MB

The sealing performance of a repository should be considered in the safety assessment of the geological disposal system of the high level radioactive waste. Nuclear Waste Management Organization of Japan and Japan Nuclear Cycle Development Institute are examining the sealing performance of the closure components (backfilling material and clay plug) to present the concept on the sealing performance required to the disposal system, and to develop the direction for the future R&D programme for the design requirements of the closure components of the presented concepts.The first step of this examination reviewed the current status of the domestic and the international sealing technologies, summarized the repository components and the repository environments, and performed the hydraulic analysis considering components on the intersections of a main tunnel and a disposal tunnel in a disposal panel and in and around the engineered barrier system (EBS). Since all tunnels connect in the underground facility, understanding of hydraulic behaviour at the intersections of the tunnels is the important issue to estimate migration of radionuclides from the EBS, and to evaluate the required sealing performance for the disposal system. The considering components in the analysis model are the intersections of the disposal tunnel and the main tunnel, the waste package, the EBS, the backfilling material, the clay plug, the concrete plug, the excavated disturbed zone, the tunnel lining and the host rock. Alteration of the concrete material (tunnel lining and concrete plug) is described as variation of the hydraulic conductivity of it. Sites of emplacement of the clay plug are the disposal tunnel and the main tunnel. No clay plug condition is also analysed. Effect of the clay plug is discussed by the results of these analyses.

Oral presentation

Hydraulic calculation for the intersections of tunnels with consideration of an interaction among sealing materials in geological repositories

Fujita, Tomo; Kawakami, Susumu*; Sugita, Yutaka*; Takahashi, Yoshiaki*; Sakai, Yuichi*

no journal, , 

In this study, three-dimensional simulations of groundwater flow are conducted to investigate the sealing performance of clay-based backfill and plug at the tunnel intersection for given hydraulic conditions around the tunnels.

Oral presentation

Hydraulic calculation for the disposal pannel with consideration of an interaction among sealing materials in geological repositories

Sugita, Yutaka*; Takahashi, Yoshiaki*; Fujita, Tomo; Kawakami, Susumu; Sakai, Yuichi*

no journal, , 

In this study, three-dimensional simulations of groundwater flow are conducted to investigate the sealing performance of clay-based backfill and plug at the disposal pannel for given hydraulic conditions around the tunnels.

Oral presentation

A Technique for their connection between parts in structural analysis method for assembly

Nishida, Akemi; Suzuki, Yoshio; Kawakami, Yoshiaki; Okada, Tatsuo; Nakajima, Norihiro

no journal, , 

A technique for their connection between parts in structural analysis method for assembly is introduced. The connection is carried out in both topologically and geometrically operation by using graph theory and rational B-spline interpolation. The smoothing of finite elements is proceed by the Laplacian operation for edges, area and vertex replacement.

Oral presentation

A Structural analysis for assembly by integrating their parts

Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Okada, Tatsuo; Tsuruta, Osamu; Suzuki, Yoshio

no journal, , 

In a finite-element analysis for the assembling structure such as nuclear power generation facilities, a technique to promote efficiency of data making including the automatic finite element generation has been researched and developed because the input data became enormous. This report discusses a technique to analyze an assembly by accumulating components' data, which are discretized report.

Oral presentation

Eigen value analysis in a structural analysis for assembly by integrating their parts

Nakajima, Norihiro; Nishida, Akemi; Okada, Tatsuo; Kawakami, Yoshiaki; Tsuruta, Osamu

no journal, , 

The input data are complicated when a finite-element structural analysis is carried out for the assembly such as nuclear related facilities. A technique for the modelling assembling parts is suggested and experimented. In this report, finite element discretization was done by every parts by parts and performed an eigenvalue analysis for an assembly. The analysis approach was experimented by using the finite-element analysis for the assembly for a continuum models and an assembly.

Oral presentation

Seismic response simulation of HTTR building against 2011 Tohoku Earthquake

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

no journal, , 

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.

Oral presentation

Time history response analysis by assembly structural analysis

Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Tsuruta, Osamu; Suzuki, Yoshio

no journal, , 

Japan Atomic Energy Agency has been developing the three-dimensional virtual shaking table for earthquake-resistant evaluations in the atomic energy facilities. It is to realize an earthquake proofing reliability examination by analyzing the earthquake-resistant of the large structure on a computer. This is the trial that is going to realize a virtual shaking table examination such as difficult size of the original structures or nuclear power generation facilities while driving on a computer. Authors develop the structure analysis cord of the assembling structure so called FIESTA (Finite Element Structural Analysis for Assembly) as one of the core functions. This is the details analytical method that paid its attention to the behavior between the part of the assembling structure as one means to perform the earthquake-resistant evaluations for such as atomic energy facilities. In this report, it is reported the way of time history response analysis by assembly structural analysis.

Oral presentation

Certainty in results of structural analysis

Nakajima, Norihiro; Nishida, Akemi; Kawakami, Yoshiaki; Suzuki, Yoshio

no journal, , 

Quality Assurance is an issue for computational science and engineering. It is well discussed in verification and validation for Simulation. In finite element analysis, it is a problem whether the finite element discretization is appropriate or not. Also, algorithmic choice prepared variously by the recent R&D discipline that become the problem which one to take. An experiment was performed for the static analysis and natural frequency analysis to confirm how uncertainty is revealed. As a result, by means to compare accuracy of the calculation precision that utilized a parallel environment, the numerical experiment reconfirmed that the estimate of the calculation solution was possible.

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