International Fusion Energy Research Center Research Articles

Overview of Broader Approach activities

The Broader Approach (BA) activities aim to complement the ITER project and to promote the early realization of fusion energy through research, development, and tests of technologies supporting the future demonstration fusion reactor (DEMO). These activities are implemented under the BA agreement, which was signed and ratified in 2007 between Euratom and the Government of Japan. In essence, the BA activities consist of three projects:a) The Satellite Tokamak Programme Project JT-60SA, the world's largest superconducting tokamak until ITER starts, aims to support the assembly, commissioning and preliminary operation of ITER, and carry out demonstration and optimisation of steady-state operation of advanced plasma configurations for DEMO;b) The International Fusion Energy Research Centre (IFERC), which comprises three different sub-projects: the DEMO Design Research and Development Coordination Centre to coordinate design and R&D on materials and components for DEMO, the Fusion Computer Simulation Centre for the simulations of fusion plasmas, the analysis of experimental data, modelling of ITER operation, and contribution to the design of DEMO, and the Remote Experimentation Centre to allow scientists to participate remotely in fusion experiments from its control room in Japan;c) The Engineering Validation and Engineering Design Activities for the International Fusion Materials Irradiation Facility (IFMIF/EVEDA) focused on the design and validation of key components needed for the future Fusion Neutron Source facilities to characterize materials envisioned for DEMO.After 13 years of fruitful collaboration, Euratom and Japan launched the second phase of the BA activities in 2020. It is focused on exploiting and enhancing the facilities that have already been built and on working more closely than ever with ITER as the latter advances towards the first plasma. This paper will present a synthesis of the achievements already obtained thanks to the three BA projects and will address the future developments planned in 2023 and beyond.

Reactivity and thermal stability of ternary Be-Zr-V beryllides

A water-cooled solid breeder blanket of a fusion reactor has been adopted in Japan, which focuses on safety concerns; safety is one of the most critical issues. In particular, as a multiplier, Be pebbles are well known to possibly generate hydrogen and react in an exothermic manner due to reaction with H2O during the loss of coolant accident. In contrast to these Be pebbles, beryllium intermetallic compounds (beryllides) demonstrate promise due to their more stable chemical reactivity at high temperatures. Currently, several studies have reported the development of advanced neutron multipliers in Japan, and the EU is part of the demonstration R&D activities at the International Fusion Energy Research Center project, which forms a part of the Broader Approach program. Fabrication methods for beryllide pebbles have been successfully developed by the combination of plasma sintering synthesis and a rotating electrode granulation method.By employing these methods, ternary beryllide pebbles with mixtures of Be13Zr and Be12V were first synthesized with ratios of 1.0:1.0, 1.0:0.8, 1.0:0.6, 1.0:0.4, 1.0:0.2, and 1.0:0.1. The small-sized Be13Zr phase as the precipitate and the Be12V phase were formed without the formation of the Be phase as these compositions did not exhibit the peritectic reaction. In addition, ternary beryllide pebbles exhibited a lower reactivity to water vapor as well as a higher thermal stability than Be pebble. In this study, not only the synthesis but also characterizations at high temperatures were discussed.

Beam diagnostics of an ECR ion source on LIPAc injector for prototype IFMIF beam accelerator

The IFMIF accelerator facility consists of 2 identical linacs, each accelerating a 125 mA CW deuteron beam up to the energy of 40 MeV. In order to reach these unprecedented performances, the Linear IFMIF Prototype Accelerator (LIPAc) is under installation and commissioning at the International Fusion Energy Research Centre (IFERC) in Rokkasho, Japan, in the framework of the IFMIF/EVEDA project, which is part of the Broader Approach (BA) agreement between Japan and EU. The accelerator is designed to validate components up to 125 mA CW deuteron beam at 9 MeV. The accelerator components of LIPAc have been designed and manufactured mainly by European Institutes. The injector and superconducting linac, RFQ, MEBT, Diagnostics Plate, HEBT and beam dump have been developed respectively by CEA-Saclay, INFN-Legnaro and CIEMAT-Madrid and were delivered to Rokkasho between 2013 and 2016. The commissioning of the injector with beam started in November 2014. This paper dealt with the experimental data obtained with the beam diagnostics of the injector. The electrical measurements of the beam intensity on the beam stopper were compared with calorimetric measurements. The beam profiles measured with a CCD camera and a custom image-intensified CID camera are also addressed. The analysis of beam emittance and ion species fractions from data obtained with an Allison scanner is described and the results of species fraction measurements are compared with those obtained by using a deported spectrometer. Finally, the analysis of beam space potential from data obtained with a 4-Grid analyser is presented.

Status of the RFQ linac installation and conditioning of the Linear IFMIF Prototype Accelerator

The Radio Frequency Quadrupole (RFQ) linac and 1.6 MW RF power system of the Linear IFMIF Prototype Accelerator (LIPAc) facility in the International Fusion Energy Research Center (IFERC) in Rokkasho (Japan) has been installed and conditioned. During the assembly and tuning process, the RFQ cavity was protected with a temporary tent from the potential deterioration of performance caused by dust. The vacuum in the cavity was improved through the 100 °C baking process of the cavity. The high power test of the 175 MHz RF systems up to 200 kW in CW for each of the eight RF chains was performed for checking its stable output reproducibility in Japan, before connecting 9–3/16 inch coaxial transmission lines from the RF chains to the RF input couplers of the cavity. It was confirmed that the eight RF chains provided the balanced RF power to the single RFQ cavity in-phase using a feedback loop and a synchronization system. The peak power in the cavity achieved 150 kW in the pulsed mode, which corresponds approximately to the required electric field to accelerate proton beam. Such RF conditioning process is ongoing to achieve 600 kW approximately required for deuteron beam commissioning planned in 2018.

Status of the ITER remote experimentation centre

The ITER Remote Experimentation Centre (REC) project (one of the three sub-projects of the International Fusion Energy Research Centre (IFERC)) is progressing under the agreement between the Government of Japan and the European Atomic Energy Community for the joint implementation of the Broader Approach (BA) activities in the field of fusion energy research. The objectives of the REC activity are to identify the functions and solve the technical issues for the construction of the REC for ITER at Rokkasho, and to develop the remote experiment system and verify the functions required for remote experimentation by using the Satellite Tokamak (JT-60SA) facilities to facilitate the future exploitation of ITER and JT-60SA. The functions of REC will be tested, and the total system will be demonstrated using JT-60SA and existing facilities in the EU, such as JET and WEST.The hardware of the REC has been prepared in Rokkasho Japan, which has the remote experiment room with a large video wall to show the plasma and operation status, IT equipment and a storage system by the reuse of the Helios supercomputer tape library. A broadband network infrastructure of 10Gbps has been installed connected to SINET5. Using this network system, fast data transfer from ITER to REC was examined in 2016, and the transfer of the data volumes expected for the initial ITER experiments has been demonstrated. A secure remote experimentation system has been developed, using JT-60SA, that has functions for preparing and setting of shot parameters, viewing the status of control data, streaming of the plasma status, data-exchange function of shot events, and monitoring of the facility operation. Remote data analysis techniques, data visualisation software, a documentation management and experiment planning system and numerical simulation codes for the preparation and performance estimation of discharges have also been developed.

Recent R&D Results on Fusion Nuclear Technology for ITER and DEMO Reactor in Japan

Several key components, such as superconducting coils, remote handling equipment, heating systems, have been designed and manufactured by JADA (Japan Domestic Agency). These activities have been carried out in accordance with the agreed schedule; in collaboration with the ITER organization and other domestic agencies. As a significant technical program using ITER, to design and to manufacture the TBS (Test blanket system), some R&D and design activities have also been conducted in Japan. Under the IFERC (the International Fusion Energy Research Center) projects of BA (Broader Approach) activities, design and R&D activities on fusion DEMO reactor have been carried out. For the DEMO R&D activity, five basic R&D subjects for a DEMO blanket system have been selected, and been studies under close collaborations between EU and JA: structure materials (RAFM steels and SiC/SiC composites), functional materials (tritium breeders and neutron multipliers), and tritium technology. From 2007, the above projects produced a set of fruitful results. A series of advanced technologies for the DEMO blanket system has also been carried out by Universities in Japan. Some significant basic R&D studies have also been carried out under US-JA collaborative program.

Recent technical progress on BA Program: DEMO activities and IFMIF/EVEDA

The Broader Approach (BA) activities consists of three major projects: the International Fusion Energy Research Center (IFERC) project, the International Fusion Materials Irradiation Facility/Engineering Validation and Engineering Design Activities (IFMIF/EVEDA) project, and the Satellite Tokamak Programme (STP, JT-60SA). These projects have been carried out to obtain basic data for the design of DEMO fusion reactor from 2007. For 8-year activities, the above projects could produce a set of fruitful results for the DEMO reactor. DEMO design activity has been conducted to build a set of DEMO design bases in accordance with a series of discussion between EU and JA. In the DEMO R&D activities, five basic R&D subjects for a DEMO blanket system have been selected, and been studies under close collaborations between EU and JA: structure materials (RAFM steels and SiC/SiC composites), functional materials (tritium breeders and neutron multipliers), and tritium technology. Some additional R&D subjects recommended by peer review comments have also been studied successfully in recent years. Regarding the IFMIF/EVEDA project, some main components of the accelerator facility been designed and tested. The validation test using EVEDA Lithium Test Loop (ELTL) was also completed successfully in October 2014.

Operation and commissioning of IFMIF (International Fusion Materials Irradiation Facility) LIPAc injector.

The objective of linear IFMIF prototype accelerator is to demonstrate 125 mA/CW deuterium ion beam acceleration up to 9 MeV. The injector has been developed in CEA Saclay and already demonstrated 140 mA/100 keV deuterium beam [R. Gobin et al., Rev. Sci. Instrum. 85, 02A918 (2014)]. The injector was disassembled and delivered to the International Fusion Energy Research Center in Rokkasho, Japan. After reassembling the injector, commissioning has started in 2014. Up to now, 100 keV/120 mA/CW hydrogen and 100 keV/90 mA/CW deuterium ion beams have been produced stably from a 10 mm diameter extraction aperture with a low beam emittance of 0.21 π mm mrad (rms, normalized). Neutron production by D-D reaction up to 2.4 × 10(9) n/s has been observed in the deuterium operation.

DEMO design activities in the broader approach under Japan/EU collaboration

The DEMO design studies in the BA (broader approach in the field of fusion energy) are being conducted by the DEMO Design Activity unit of International Fusion Energy Research Centre for the broader approach (BA) and the Home Teams in EU and Japan since 2011. The activity covers most of the critical issues on the DEMO design. Emphasis during the last two years was on studies to develop the best embodiment of a tokamak as a power reactor consistent with credible operating scenarios and feasible engineering solutions to critical design issues. The technical activities have focused on, for example, plasma physics for DEMO plants, divertor physics and technology, in-vessel components, maintenance schemes and safety research.

Overview of CEA Contributions to the Broader Approach Projects

France is participating as one of the European voluntary contributors to the joint Europe-Japan so-called Broader Approach (BA) activities in support of ITER and DEMO activities, consisting of three projects: the engineering design and validation of a 14-MeV-neutron irradiation facility (IFMIF-EVEDA), the building of the International Fusion Energy Research Centre (IFERC), and the ITER Satellite Tokamak Programme (STP-JT-60SA). This paper gives an overview of the French contributions to the BA projects and reports on the present status of these projects since 2007.

Present Status and Achievements of Broader Approach Activities

Five years have passed since the Broader Approach (BA) activities launched in 2007 under the framework of collaboration between Japan and EURATOM. In the International Fusion Materials Irradiation Facility (IFMIF) Engineering Validation and Engineering Design Activities (EVEDA) project, commissioning of the prototype lithium test loop was completed in March 2011, and a lithium flow of 25 mm thick at 15 m/s was obtained in July 2012. Components of the prototype accelerator are being fabricated. Injector will be delivered in Rokkasho in March 2013 followed by the validation test of the accelerator. In the International Fusion Energy Research Center (IFERC) project, five R&Ds mainly on DEMO blanket are being carried out at a newly constructed DEMO R&D facility. A high performance supercomputer with a LINPAC performance of 1.27 Pflops is now operational for the fusion simulation. In the Satellite Tokamak Program (STP) project, JT-60 torus disassembly is almost completed, and manufacture of tokamak components such as PF coils, vacuum vessel, cryostat are being fabricated on schedule. JT-60SA construction will start in Dec.2012. Present status and recent achievements of these BA activities are summarized.

Progress and achievements of the BA activities in Rokkasho

In Rokkasho Japan, the International Fusion Energy Research Center (IFERC) project and the International Fusion Materials Irradiation Facility/Engineering Validation and Engineering Design Activities (IFMIF/EVEDA) project are on going under the Broader Approach framework. The IFERC project consists of three sub-projects; a fusion demonstration reactor (DEMO) Design and R&D Coordination Center, a Computational Simulation Center (CSC), and an ITER Remote Experimentation Center (REC). DEMO Design activity has been conducted by the IFERC project team in Rokkasho and home teams in EU and JA. In the DEMO R&D activity, five R&D tasks mainly of the blanket materials are carried out intensively. A supercomputer with 1.23 Pflops of LINPAC performance has been installed in December 2011, the operation started in January 2012. Discussion of overall plan of REC has started in 2012 between EU and Japan. In the IFMIF/EVEDA project, an IFMIF prototype accelerator system up to 9MeV with 125mA CW deuteron beam will be installed and tested in Rokkasho. Major components of the accelerator are under development or fabrication in EU. The first component of the accelerator, an injector with an ECR ion source, will be delivered to Rokkasho in March 2013.

Progress of fusion nuclear technologies in the broader approach framework

In the Broader Approach framework, the International Fusion Materials Irradiation Facility/Engineering Validation and Engineering Design Activities (IFMIF/EVEDA) project, the International Fusion Energy Research Center (IFERC) project, and the Satellite Tokamak project are implemented. In the IFMIF/EVEDA project, engineering design of IFMIF and engineering RD include the construction and tests of an IFMIF prototype accelerator system up with a 9 MeV and ON deuteron beam, a liquid lithium test loop with free surface flow, and full scale irradiation test module including temperature control instrumentation. The commissioning of the EVEDA lithium test loop was completed in March 2011, and a lithium flow of similar to 5 m/s was obtained. As a part of the IFERC project, RD on reduced activation ferritic/martensitic steels as blanket structural material, SiCf/SiC composites as a flow channel insert material and/or alternative structural material, advanced tritium breeders and neutron multipliers, and tritium technology are carried out. At the beginning of 2011, the integrated DEMO design team was established among the IFERC project team and EU/JA home teams, where the design criteria, other design basis are discussed as an initial work. A high performance supercomputer with the peak performance of 1.3 Pflops is under installation at the Rokkasho BA site. (C) 2012 Elsevier B.V. All rights reserved.

Technical issues related to the development of reduced-activation ferritic/martensitic steels as structural materials for a fusion blanket system

Reduced activation ferritic/martensitic (RAFM) steels are recognized as the primary candidate structural materials for fusion blanket systems. Because of the possibility of creating sound engineering bases, such as a suitable fabrication technology and a materials database, RAFM steels can be used as structural materials for pressure equipment. Further, the development of an irradiation database in addition to design methodologies for fusion-centered applications is critical when evaluating the applicability of RAFM steels as structural materials for fusion-neutron-irradiated pressure equipment. In the International Fusion Energy Research Centre (IFERC) project in the Broader Approach (BA) activities between the EU and Japan, R&D is underway to optimize RAFM steel fabrication and processing technologies, develop a method for estimating fusion-neutron-irradiation effects, and study the deformation behaviors of irradiated structures. The results of these research activities are expected to form the basis for the DEMO power plant design criteria and licensing. The objective of this paper is to review the BA R&D status of RAFM steel development in Japan, especially F82H (Fe–8Cr–2W–V, Ta). The key technical issues relevant to the design and fabrication of the DEMO blanket and the recent achievements in Japan are introduced.

Progress of IFERC project in the Broader Approach Activities

For contributing to the ITER project and promoting a possible early realization of DEMO, since 2007 the International Fusion Energy Research Centre (IFERC) shall perform the activities on (1) DEMO Design and R&D Coordination, (2) Computational Simulation Centre, and (3) ITER Remote Experimentation Centre in the framework under the agreement between the Government of Japan and the European Atomic Energy Community for the joint implementation of the Broader Approach Activities in the field of fusion energy. The DEMO Design activity aims at establishing a common basis for DEMO Design, including design features of DEMO, possible common concepts of DEMO, a roadmap for DEMO, and so on. Based on the common interest of EU and Japan toward DEMO, the DEMO R&D activities have been planned and carried out for the areas which are related to DEMO blanket development: SiC/SiC composites, tritium technology, materials engineering, advanced neutron multiplier, and advanced tritium breeders for DEMO blanket. In the activity of the Computational Simulation Centre, the objective is to provide and exploit a supercomputer for large scale simulation activities to analyse experimental data on fusion plasmas, prepare scenarios for ITER operation, predict the performance of the ITER facilities and contribute to the DEMO Design.

ITER計画とBA活動の現状 : 核融合エネルギーの実現に向けた国際プロジェクト(基調講演)

ITER is a world collaborative project being undertaken jointly by EU, Japan, Russia, US, China, Korea and India with the objective of demonstrating the scientific and technological feasibility of fusion energy by producing a reactor-relevant burning plasma in Tokarnak type fusion machine. ITER Organization was established in 2007 to construct the ITER in Cadarache, south France. A platfonn with 1km in length, 400m in width is ready for building construction. Fabrication of the super conduction magnets and other components have been started in Japan. The Broader Approach (BA) project has been launched also in 2007 under the framework of collaboration between Japan and EU. The BA project aims at complementing the ITER project and at an early realization of fusion energy by carring out R&D and developing some advanced technologies for the future demonstration power reactor (DEMO). A new research site named "International Fusion Energy Research Center" has been established in Rokkasho, Aomori as a center of the BA project.

Status of the BA-IFERC Activities in Japan

The Broader Approach (BA) activities have been launched in 2007 under the framework of collaboration between Japan and EURATOM. The BA activities aim at complementing the ITER project and at an early realization offusion energy by carrying out R&D and developing some advanced technologies for the future demonstration power reactor (DEMO). Three research projects are to be undertaken in Japan. They are 1) Engineering Validation and Engineering Design Activities for the International Fusion Materials Irradiation Facility (IFMIF/EVEDA), 2) International Fusion Energy Research Center (IFERC), and 3) Satellite Tokamak Program, where the JT-60 tokamak will be upgraded to an advanced superconducting tokamak.The IFERC project is to be carried out at a new research site prepared in Rokkasho, Aomori, Japan. The construction of the buildings started in March 2008 and will be completed in FY 2009 (March 2010), followed by the installation of the experimental equipments for the DEMO R&D.

Broader Approach to fusion energy

The Broader Approach activities aim at complementing the ITER project and at an acceleration of fusion energy in the framework of collaboration between Japan and EURATOM. Three research projects are to be undertaken: (1) Satellite Tokamak Programme, (2) Engineering Validation and Engineering Design Activities for the International Fusion Materials Irradiation Facility (IFMIF/EVEDA), and (3) International Fusion Energy Research Centre (IFERC). While the Satellite Tokamak Programme is to be conducted at the site of the existing JT-60 tokamak, the other two projects are to be undertaken at a new research site in Rokkasho, Japan.

Overview of Recent Japanese Activities and Plans in Fusion Technology

For ITER, trial fabrications of a superconducting cable for a Toroidal Field coil conductor and jacket sections for a central solenoid conductor were successfully performed. In the radio-frequency heating technology, development of 170 GHz ITER gyrotron has progressed to achieve a 600 kW for 3600 sec operation in JAEA RF test stand. In LHD, long-pulse operations near 1 hour with 1.6 GJ inputs have been achieved with ICH and ECH, and subcooled operations of SC magnets to improve cryogenic stability are scheduled soon. In the ITER Test Blanket Modules project, Japan has a plan to lead a water cooled ceramic breeder blanket concept, and to cooperate with other parties on other blanket concepts, such as, a helium cooled ceramic breeder blanket, a LiPb blanket, a Li/V blanket, and a molten salt blanket. As the Broader Approach activities between Europe and Japan, ITER satellite tokamak, JT-60SA, IFMIF-EVEDA and the International Fusion Energy Research Center programs will start soon in Naka and Rokkasho, respectively. Basic researches on broad areas have been enhanced with collaborations in the Fusion Engineering Network among Japanese universities and research institutes.