Transport and confinement physics Chapter 2 of the special issue: on the path to tokamak burning plasma operation

Yoshida, M.*; McDermott, R. M.*; Angioni, C.*; Camenen, Y.*; Citrin, J.*; Jakubowski, M.*; Hughes, J. W.*; Idomura, Yasuhiro; Mantica, P.*; Mariani, A.*; et al.

Nuclear Fusion, 65(3), p.033001_1 - 033001_132, 2025/02

https://doi.org/10.1088/1741-4326/ad8ced

Progress in physics understanding and theoretical model development of plasma transport and confinement in the ITPA Transport and Confinement Topical Group since the publication of the ITER Physics Basis was summarized focusing on the contributions to ITER and burning plasma prediction and control. This paper provides a general and streamlined overview on the advances that were mainly led by the ITPA TC joint experiments and joint activities for the last 15 years. This paper starts with the scientific strategy and scope of the ITPA TC Topical group and overall picture of the major progress, followed by the progress of each research field: particle transport, impurity transport, ion and electron thermal turbulent transport, momentum transport, impact of 3D magnetic fields on transport, confinement mode transitions, global confinement, and reduced transport modeling.

GPV2OSC, meteorological data format conversion program for OSCAAR

Risk Analysis Research Group, Reactor Safety Research Division, Nuclear Safety Research Center

JAEA-Data/Code 2024-006, 40 Pages, 2024/07

JAEA-Data-Code-2024-006.pdf:1.92MB

The Risk Analysis Research Group, Reactor Safety Research Division, Nuclear Safety Research Center, Sector of Nuclear Safety Research and Emergency Preparedness, Japan Atomic Energy Agency has been developing OSCAAR, a probabilistic risk assessment program for nuclear facility accidents. OSCAAR has the feature to calculate atmospheric concentrations of radioactive materials using an atmospheric dispersion model. This feature requires the input of meteorological data about wind speed, precipitation rate, atmospheric stability and so on. However, to use numerical weather prediction data created from the Japan Meteorological Agency (JMA) on OSCAAR, it is necessary to convert the data format to match OSCAAR input format in advance. Therefore, we developed GPV2OSC, a pre-processing program for OSCAAR, to create meteorological data converted from JMA weather prediction data format to OSCAAR input format when the target region and period are specified. This report describes the outline and usage of GPV2OSC.

Technology information on High Temperature Gas-cooled Reactor (HTGR)

HTGR Design Group, HTGR Project Management Office

JAEA-Technology 2023-019, 39 Pages, 2024/01

JAEA-Technology-2023-019.pdf:1.34MB

In order to realize the development of the demonstration reactor of High Temperature Gas-cooled Reactor (HTGR) with a target of starting operation in the 2030s, as indicated in the "Basic Policy for GX Realization" (Cabinet Decision on February 10, 2023) and the Working Group on Innovative Reactors of METI, Japan Atomic Energy Agency (JAEA) has been working on the development of a standard for the development of a HTGR under the Atomic Energy Society of Japan and the Japan Society of Mechanical Engineers. In addition, JAEA has been commissioned by the Agency for Natural Resources and Energy of the Ministry of Economy, Trade and Industry (METI) to conduct the "Demonstration Project for Mass Hydrogen Production Technology Using Ultra-High Temperatures" and has been promoting a hydrogen production project using the HTTR (High Temperature Engineering Test Reactor). Furthermore, in collaboration with the National Nuclear Laboratory (NNL) of the United Kingdom and the National Centre for Nuclear Research (NCBJ) of Poland, JAEA are aiming to strengthen the international competitiveness of HTGR technology by further upgrading the HTGR technology developed in Japan through the construction and operation of the HTTR. In response to the growing interest in HTGR development in Japan and abroad, we have developed FAQs on HTGR related technologies in order to provide accurate technical information on HTGRs.

Investigations on distribution of radioactive substances owing to the Fukushima Daiichi Nuclear Power Station Accident in the fiscal year 2021 (Contract research)

Group for Fukushima Mapping Project

JAEA-Technology 2022-026, 152 Pages, 2023/01

JAEA-Technology-2022-026.pdf:20.14MB

This report presents results of the investigations on the distribution-mapping project of radioactive substances owing to TEPCO Fukushima Daiichi Nuclear Power Station (FDNPS) conducted in FY2021. Car-borne surveys, a flat ground measurement using survey meters, a walk survey and an unmanned helicopter survey were carried out to obtain air dose rate data to create air dose rate distribution maps, and temporal changes of the air dose rates were analyzed. Surveys on depth profile of radiocesium and in-situ measurements as for radiocesium deposition were performed. Based on these measurement results, effective half-lives of the temporal changes in the air dose rates and the deposition were evaluated. Score maps to classify the importance of the measurement points were created for Fukushima Prefecture and the 80 km zone from the FDNPS, and the factors causing changes in the score when monitoring data from multiple years were used were discussed. Monitoring data in coastal area performed owing to the comprehensive radiation monitoring plan until 2020 was summarized, and temporal changes in cesium-137 were analyzed. Using the Bayesian hierarchical modeling approach, we obtained maps that integrated the air dose rate distribution data obtained in this project with respect to the region within 80 km from the FDNPS and Fukushima Prefecture. The measurement results for FY2021 were published on the "Expansion Site of Distribution Map of Radiation Dose", and measurement data were stored as CSV format. Radiation monitoring and analysis of environmental samples owing to the comprehensive radiation monitoring plan were carried out.

JENDL-4.0 benchmark test with shielding experiments

Shielding Integral Test Working Group, JENDL Committee

JAEA-Research 2021-015, 86 Pages, 2022/03

JAEA-Research-2021-015.pdf:6.15MB

The major revised version of Japanese Evaluated Nuclear Data Library (JENDL), JENDL-4.0, was released in May, 2010. Thus Shielding Integral Test Working Group in JENDL Committee has performed benchmark tests of JENDL-4.0 for the shielding and fusion neutronics fields in order to verify accuracy of JENDL-4.0. We adopted many benchmark experiments: 1) the in-situ and Time-of-Flight (TOF) experiments with DT neutrons at JAEA/FNS, 2) the TOF experiments with DT neutrons at Osaka Univ./OKTAVIAN, 3) the aluminum, iron, nickel and lead experiments with DT neutrons at IPPE, Russia, 4) the iron and stainless steel experiments at ORNL/TSF, US, 5) the ASPIS iron experiment at Winfrith, England, 6) the iron experiments with Cf neutron source at KfK, Germany and 7) the iron experiments with Cf neutron source at NIST, US. These experiments were analyzed by using the Monte Carlo code MCNP4 or MCNP5 and/or Sn codes ANISN, DOT3.5 and DORT with mainly JENDL-3.3 and JENDL-4.0. The calculated results demonstrated that JENDL-4.0 led to better agreements with the measured data due to revisions of JENDL-3.3 problems.

Final report of the covariance data utilization and promotion WG in the JENDL committee

Covariance Data Utilization and Promotion Working Group, JENDL Committee

JAEA-Review 2021-014, 139 Pages, 2021/09

JAEA-Review-2021-014.pdf:3.87MB

The Covariance Data Utilization and Promotion Working Group organized in the JENDL committee has worked for three years to study the following five issues: (1) to identify uncertainties which have not yet been quantified or which are too difficult to be quantified, (2) to identify uncertainties which have been quantified, but whose reasonable bases are too weak, (3) to propose realistic methods to assure the reliability of the covariance data, (4) to propose actions which should be taken in the fields of nuclear data measurement, evaluation and application to promote the covariance data utilization, and (5) to make a recommendation how the covariance data are treated and positioned in Japanese evaluated nuclear data library, JENDL. This final report summarizes the outcomes of this working group. This report is organized as follows. First, the fundamental information/issues on the nuclear data uncertainties are briefly described, and then the current status and issues of the covariance data evaluation and utilization in the fields of the nuclear data measurement, evaluation and application are presented. Furthermore, several methods to assure the reliability of the covariance data are proposed, and finally, some guidelines such that what kind of covariance data provided in the evaluated nuclear data files are desirable, and what kinds of attention the users should take care in utilizing the covariance data are proposed as a conclusion of the working group.

User's manual for the OSCAAR code package

Radiation Risk Analysis Research Group, Risk Analysis and Applications Research Division

JAEA-Testing 2020-001, 65 Pages, 2020/03

JAEA-Testing-2020-001.pdf:4.42MB

The Nuclear Safety Research Center (NSRC) has developed a Level 3 Probabilistic Risk Assessment (PRA) code, the OSCAAR (Off-Site Consequence Analysis code for Atmospheric Release in Reactor Accident). Using a source-term derived from a severe accident analysis code, OSCAAR calculates the downwind transport, airborne dispersion, and ground deposition of radioactive materials as well as the radiation dose and then can evaluate the effect of early and late protective actions and health effect. The NSRC also developed the OSCAAR Code Package that has a Windows-based interface and framework for performing consequence analysis in order to create or modify input files, execute the OSCAAR and postprocess the output files efficiently and conveniently. The report is a user's manual for the OSCAAR Code Package.

Fission product chemistry database ECUME version 1.1

Development Group for LWR Advanced Technology

JAEA-Data/Code 2019-017, 59 Pages, 2020/03

JAEA-Data-Code-2019-017.pdf:3.26MB
JAEA-Data-Code-2019-017-appendix(CD-ROM).zip:0.09MB

ECUME (ffective hemistry database of fission products nder ultiphase raction) is the database for the analyses of FP chemistry which strongly affects all the FP behaviors in a severe accident (SA) of nuclear facility like LWR. ECUME consists of three kinds of datasets: CRK (dataset for hemical eaction inetics), EM (lemental odel set) and TD (hermoynamic dataset). The present version of ECUME is prepared especially for the more accurate evaluation of cesium and iodine distribution in a reactor and release amount into an environment which should be of crucial importance towards the decommissioning of Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Company Holdings (1F) and the enhancement of LWR safety after the 1F SA.

J-PARC RCS; Effects of emittance exchange on injection painting

Hotchi, Hideaki; J-PARC RCS Beam Commissioning Group

Proceedings of 61st ICFA Advanced Beam Dynamics Workshop on High-Intensity and High-Brightness Hadron Beams (HB 2018) (Internet), p.20 - 25, 2018/07

https://doi.org/10.18429/JACoW-HB2018-MOP1WA01

no abstracts in English

Compilation of the data book on light water reactor benchmark to develop the next version of JENDL; Utilization of criticality data in ICSBEP and IRPhEP open databases

Reactor Integral Test Working Group, JENDL Committee

JAEA-Data/Code 2017-006, 152 Pages, 2017/05

JAEA-Data-Code-2017-006.pdf:13.46MB
JAEA-Data-Code-2017-006(errata).pdf:0.07MB
JAEA-Data-Code-2017-006-appendix1(CD-ROM).zip:115.88MB
JAEA-Data-Code-2017-006-appendix2(CD-ROM).zip:110.88MB

A benchmark database which is devoted to the evaluation of the future JENDL against the criticality of light water reactors was prepared, where the ICSBEP and IRPhEP handbooks by OECD/NEA were utilized effectively. Specific features of this report can be described as follows: (1) The recommendation for benchmarking is based on careful reviewing for the document and related information. Validity of the original benchmark evaluation is carefully checked, and numerical results obtained with JENDL-4.0 are considered. (2) Heterogeneity effect of PuO particles dispersed in fuel medium is consistently quantified for the MOX fuel-loaded experimental data. This precise evaluation is realized by the newly developed finite fuel pin bundle model with the Monte Carlo neutron transport code. (3) Sensitivity analysis is conducted in order to specify nuclear data whose difference between recent nuclear data libraries significantly affects the critical parameter calculation.