National Institute of Natural Sciences
National Institute for Fusion Science

NIFS Peer Review Reports in FY2019

March, 2020

National Institute for Fusion Science
Advisory Committee External Peer Review Committee

Contents
Chapter 1 Background ······························································································· 1

Chapter 2 Summary of the Evaluation, and Recommendation ················· 6[1] Summary of Evaluation ··················································································· 6[2] Recommendations ························································································· 11

Chapter 3 In Closing ································································································· 13

Documents
1. 2019 External Peer Review Presentation Materials

References
1. Table of Evaluation Results for the 2019 External Peer Review

Chapter 1 Background
The National Institute for Fusion Science (below as NIFS) was established in 1989 as aninter-university research institute, and utilizes the Large Helical Device (below as LHD) as theprincipal device to advance fusion research in universities in Japan.
The LHD, which was planned by bearing the support and the expectations of the fusion
community, has the special characteristic of producing the heliotron-type magnetic field, which is anidea unique to Japan. In addition to generating high-performance helical-type plasma through highpower heating, NIFS is advancing with experimental research that aims to clarify physical andtechnological issues for realizing the toroidal magnetic field confinement fusion reactor. On the other
hand, parallel with this, in analyses of fusion plasmas having fundamental complexities, theoreticalresearch that uses large-scale simulations is essential. For that reason, a supercomputer for exclusive
use was introduced at NIFS. We are advancing with leading-edge research by making thissupercomputer at NIFS available for use to fusion theory researchers in Japan through collaborative
research. Moreover, since 2010, in order to further strengthen the centripetal power of NIFS as a Centerof Excellence (below as COE) in the field of plasma and fusion research we have organized threeresearch projects, these being LHD, theory and simulation, and reactor engineering. Looking forward
toward achieving the fusion reactor, initiated research programs will integrate these research results.
In addition to having revised the research structure within NIFS and having placed all
research staff in one research department, by establishing a research system that enables participation
by free will in research projects and has enabled easier cooperation in the three projects of LHD, theory
and simulation, and reactor engineering than in the past, we are increasingly able to respondresourcefully to new topics.
In this period, there have been changes to the structure of the domestic academic researchsystem. Since 2004, NIFS has been a research institute under the Inter-University Research InstituteCorporation National Institutes of Natural Sciences (below as NINS) for enhancing further thedomestic research collaboration. Upon becoming an inter-university research corporation, a system
for mid-term goals and mid-term planning spanning six years was introduced, and a system of annual
evaluations regarding the progress, too, was introduced. This annual evaluation focuses primarily uponadministrative management. However, at NIFS it has been determined that receiving external
evaluations of research results is important. Under the NIFS Advisory Committee, each year anExternal Peer Review Committee is organized and the members evaluate the research. The topics ofevaluation are determined by the Advisory Committee. The evaluation is undertaken by the membersof the External Peer Review Committee, which is composed of experts who are external members of
the Advisory Committee and external experts who are appropriate for evaluating the topics. The
External Evaluation Committee submits its evaluation results to the Advisory Committee. Then, NIFS,-1-

together with making the results public by uploading that information to the NIFS homepage, utilizes
this information to improve research activities in the following years.
The topics for evaluation for the External Peer Review Committee are discussed and decided
upon by the Advisory Committee, and those topics for evaluation differ each year. Most recently, in2016 Collaborative Research, in 2017 the Reactor Engineering Research Project, and in 2018 Large
Helical Device Project were topics evaluated by external reviewers. This year, 2019, the “Numerical
Simulation Reactor Research Project” was selected and reviewed by the external examiners.
As external members of the External Peer Review Committee there were ten external
members from the Advisory Committee and three members from foreign countries. Further, there were
two experts from outside NIFS and one expert from abroad. Thus was the External Peer Review
Committee composed, and thereby the evaluation was undertaken.
The first meeting of the External Peer Review Committee including the Experts’ Committee
was convened on October 23, 2019. The Committee discussed the process for moving forward withthis fiscal year’s external peer review, and decided upon the perspective of the evaluation. On
November 23, 2019, the second meeting of the External Peer Review Committee and Experts’Committee was held. From NIFS was provided a detailed explanation that utilized documents fromthe material of viewgraphs and reports based on the perspectives (see the documents section). A
question-and-answer session also was held. Subsequently, the third meeting of the External Peer
Review Committee and the Experts’ Committee was held on January 28, 2020. Together with holding
another question and answer session with NIFS, evaluation work based on the topics of the evaluationand the coordination of the evaluation work were undertaken. We compiled the external peer review
report (draft) based upon the discussions to this point, and further discussions were held by electronic
mail. Upon confirmation and examination by the External Peer Review Committee and the Experts’Committee, we compiled the final report. Please see Reference Material 4 for the meeting schedule of
the External Peer Review Committee and the Experts’ Committee.
Moreover, in the external evaluation regarding “Numerical Simulation Reactor Research
Project” which was implemented this fiscal year, the perspectives for the evaluation were determined
as follows. The perspectives for the evaluation are considered indispensable in the evaluation of the“Numerical Simulation Reactor Research Project” promoted by NIFS which NINS decided upon in
the mid-term planning. These perspectives are the basis of the evaluation of achievements and theevaluation of the level of research.
Further, we have consulted the following points in the evaluation which are based upon therecommendations implemented in the External Peer Review Report of the “Numerical Simulation
Reactor Research Project” in 2015.

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Evaluation items regarding the Numerical Simulation Reactor Research
Project - FY2019 External Peer Review
The items mentioned hereinafter consist of all the aspects that are indispensable inevaluating the performance of NIFS's Numerical Simulation Reactor Research Project(NSRP) under the mid-term plan issued by NIFS's parental body, the National Institutesof Natural Science. Reviewers will assess the levels of goal attainment and scientificquality.
The following proposals from the previous review regarding the NSRP in FY2016 aretaken into account in the evaluation this time.
1)

It is necessary to show clearly the final goal of the NSRP, share it with each research group,
strengthen the check system for the progress of the research group's goal, and pay attention to the
management in order to produce the synergy effect by collaboration between research groups.

2)

The research plan and system should be speedily improved and strengthened by being constantly
aware of combining and integrating the developed elements with a roadmap in a view for finallycompleting the integration.

3)

Regarding the Plasma Simulator and the improvement of the related research environment, it ishoped to check the progress of each group in the entire project and take it into account for making
plans suitable for step-by-step goals. In particular, regarding the supercomputer system which isindispensable for the integration, it is recommended to actively promote the installation of ahigher performance supercomputer toward the future for making contributions to further thedevelopment of plasma and fusion research.

4)

It is recommended to maintain and develop the research system in which
researchers contribute to both project promotion and scientific progress. In addition,
it is hoped to improve competitiveness, which enables information dissemination toother research fields, and contributes to the creation of new academic fields throughinterdisciplinary activities.

5)

For the purpose of maintaining high-level simulation research activities necessary
for developing the fusion reactor, it is recommended to systematically commit tohuman resource development with universities, and further enhance both quality
and quantity.

Evaluation items in FY2019 External Peer Review
1. Development of research plan, system, and environment

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（1）

Does the Numerical Simulation Reactor Research Project (NSRP)

appropriately set the goal and plan including the roadmap for constructionof the Numerical Simulation Reactor? Are they properly discussed foraccomplishing the third midterm target and plan?
（2）

Does the research system function appropriately in accomplishing theobjectives of the NSRP with attention to the management of step-by-step
progress, research collaboration, and integration?
（3）

Is the environment of the “Plasma Simulator” system and its related

research appropriately developed and effectively utilized accordingly to theresearch plan? Is the installation of a higher performance supercomputer
properly planned?
2. Research achievements
Does the NSRP produce high-level achievements in accordance with international
standards for the following research areas described in the third midterm goal andplan by promoting theory and computer simulation research utilizing the Plasma
Simulator?
（1）

Construction of the Numerical Simulation Reactor, Validation andimprovement of simulation codes through comparison to experimental
results（2）

Academic systematization of fusion science and related science andengineering（3）

Are research achievements steadily made according to the plan of the

NSRP?
3. Promotion of cooperation and collaboration（1）

Is collaboration research with universities based on theory andsimulation research appropriately promoted?

Does it contribute to theprogress of the NSRP?
（2）

Does the NSRP contribute to enhancing functions of universities andinstitutes as the center of excellence for fusion plasma simulation? Does
the NSRP commit to the promotion of interdisciplinary collaboration andresearch?
（3）

Does the NSRP contribute to international cooperation including ITER,

BA activities, and others through international collaboration activities?

-4-4. Human resources development（1）

Does the NSRP contribute to the development of human resources

required for maintaining high-level simulation research activities toward
the future?
5. Future plan（1）

Is the future research plan suitable for progressing toward the goal of

the NSRP? Does it also contribute to establishing the future plan of the
National Institute for Fusion Science?

-5-Chapter 2 Summary of the Evaluation, and Recommendation
We summarize the key points of the evaluation, and report in writing the recommendation regarding
promotion of the Numerical Simulation Reactor Research Project.
［１］Summary of the Evaluation
1. Development of research plan, system, and environment（１）Does the Numerical Simulation Reactor Research Project (NSRP) appropriately
set the goal and plan including the roadmap for construction of the Numerical
Simulation Reactor? Are they properly discussed for accomplishing the third
midterm target and plan?
The Numerical Simulation Reactor Research Project (NSRP) is appropriately
positioned and promoted as one of the major research projects of NIFS in the third midterm target and plan. The NSRP plays an important role not only in research of helicalsystems represented by LHD but also in research of tokamaks from the viewpoint ofinteractive and synergistic studies. This is a distinctive research project that aims at
high-precision and high-resolution modeling based on experimental data. It is hoped that
the NSRP will reaffirm its significance and contribute to the achievement of theobjectives as well as the advancement of science while succeeding and developing thehistory of NIFS, which has contributed deeply to the progress in a wide range ofsimulation science.
Since this is a long-term plan, it will be necessary to reexamine the roadmap for therealization of the Numerical Simulation Reactor and flexibly modify the research plan
toward integration of developed simulation codes in accordance with results ofexperimental research and scientific progress. It is desirable to pursue innovation ofsimulation research and aim for leadership in academic research.
（２）Does the research system function appropriately in accomplishing the objectivesof the NSRP with attention to the management of step-by-step progress, researchcollaboration, and integration?
It is highly evaluated that the NSRP sets up appropriate milestones, checks the stepby-step progress, and organizes eight task groups to manage research collaboration and-6-integration. Constructing a collaborative research system that includes outside
researchers and holding management meetings across the task groups, smooth
information exchange is enhanced and a framework that conducts the project with acommon awareness is established. Coordination with other projects is being promoted
appropriately, and the research system is generally functioning effectively.
However, since the bottom-up research promotion system may not work effectively interms of integration, it is necessary to take appropriate measures while viewing theentire research plan. It is hoped that academic research will be further advanced andlead to better achievements by enhancing organized collaboration between the task
groups and making effective use of human resources.
（３）Is the environment of the “Plasma Simulator” system and its related research
appropriately developed and effectively utilized according to the research plan?
Is the installation of a higher performance supercomputer properly planned?
The environment of the Plasma Simulator and its related research has been properly
developed, updated, and maintained in accordance with the research plan, and has beeneffectively used at a high utilization rate. Not only the hardware environment but also
the software support activities for users are implemented, and an excellent environmentthat supports fusion theory and simulation research has been constructed. It is an
important resource for activating collaborative research with outside organizations andis expected to be used even more effectively in maintaining the competitiveness ofJapan's simulation science.
In addition, it is necessary to clarify the position of the NSRP in the field of simulation
science, and to strategically promote the formulation and the execution of the researchplan.
2. Research achievements
Does the NSRP produce high-level achievements in accordance with international
standards for the following research areas described in the third midterm goal andplan by promoting theory and computer simulation research utilizing the Plasma
Simulator?
（１）Construction of the Numerical Simulation Reactor, validation and improvementof simulation codes through comparison to experimental results-7-

Many research results have been created and outstanding progress has been made byusing the codes developed in the NSRP, and also by comparing simulation results withexperimental results. The simulation codes have been improved and partially integrated,
contributing to the LHD Project. Original and excellent research results have beenachieved at each hierarchical level, and the sophistication of the codes is progressing
smoothly. The broad development is highly evaluated although it will be necessary toconsider focusing human resources because they cannot be sufficiently allocated to allthemes. It is hoped that the NSRP will continue research for elucidation of the essential
physics such as multi-scale coupling in the future.
（２）Academic systematization of fusion science and related science and engineering
The NSRP is appropriately positioned in the third mid-term target and plan, and it
can be evaluated as contributing to the academic systematization of fusion science andrelated sciences and technology. In particular, it is highly evaluated that the NSRP
disseminates the research achievements to academic societies through presentations ofhigh-level results, actively publishing textbooks and review papers, and engaging inenlightenment activities. Overall, it is evaluated as progressing.
It is desired that the NSRP will actively pursue research subjects of high academic
value common to other fields, such as multi-scale simulation. The goal of the NSRP
aiming at integration itself can be said to be academic systemization. Further efforts toachieve this goal are expected.
（３）Are research achievements steadily made according to the plan of the NSRP?
The resources such as the Plasma Simulator have been effectively utilized to achieve
numerous results in the theory and simulation research while systematically developing
and extending many simulation codes required to promote the NSRP. In particular, thePlasma Simulator is utilized at a high rate for collaborative research, and it functions as
a core project of the researchers' community. The research achievements are alsopresented and disseminated in a form that is easily visible to society, and steady progress
is being made in research. The NSRP is also actively working on application of the codes,
such as designing a new device for the future plan, and it is evaluated that the past
research has been bearing fruit.
On the other hand, there are differences in the progress of research and the numberof presentations among the research groups, and it is feared that a new academic-8-

challenge will not be created if it falls into a mission research promotion system withlimited subjects. It is hoped that, with a view to expanding into other fields, the NSRP
always maintains a challenging spirit for unexplored issues, which will lead to further
development of the project and the development of new academic fields.
3. Promotion of cooperation and collaboration（１）Is collaboration research with universities based on theory and simulation research
appropriately promoted? Does it contribute to the progress of the NSRP?
The NSRP promotes collaboration with universities nationwide, accepts about seventy
collaborative researches with nearly two hundred collaborators from inside and outside
NIFS, holds Plasma Simulator Symposia for active discussion and information exchangewith domestic researchers, and contributes to activating the field of theory andsimulation. Thus, it can be evaluated that collaborative research with universities basedon the theory and simulation research is being carried out appropriately.
The role of NIFS as a center of collaborative research is critical. In addition topromoting the projects, it is expected to play an active and leading role in relationships
with other institutes and various fields. It will also be useful in the future to carry out
quantitative evaluations such as counting the number of collaborators in the eightresearch groups organized in the NSRP.
（２）Does the NSRP contribute to enhancing functions of universities and institutes as
the center of excellence for fusion plasma simulation? Does the NSRP commit to
the promotion of interdisciplinary collaboration and research?
The NSRP has achieved results in a wide range of research fields by conducting
collaborative research with many universities and research institutes. In addition to
applying the simulation codes developed by NIFS for actively supporting experimental
research carried out at universities, the NSRP holds many workshops every year andplays a central role in exchanging information among researchers in the universities. It
is highly evaluated as contributing to the enhancement of the functions of universities
and institutes as a center for fusion plasma simulation. Furthermore, it can be evaluatedthat the NSRP is committing to collaboration with the astronomy field in the NINS,
interdisciplinary collaboration such as molecular dynamics simulation on DNA damage,and promotion of research for fusion of different fields.

-9-

It is expected that the NSRP will increase competitiveness against other fields andfurther promote international and academically valuable collaborations while using
results obtained from the construction of the Numerical Simulation Reactor to found abasis for building a universal science.
（ ３ ） Does the NSRP contribute to international cooperation including ITER, BA
activities, and others through international collaboration activities?
It is highly evaluated that the NSRP actively contributes to the ITER Project, BA
activities and a wide range of international cooperation such as Japan-US, Japan-EU
collaborations, Japan-China-Korea Foresight Program, International Tokamak Physics
Activity (ITPA), ITER Integrated Modelling Expert Group (IMEG), and IFERC Project.
On the other hand, in order to spread the excellent codes developed in NIFS asinternational standards, it is necessary to further enhance international collaborationand systematically carry out dissemination activities. It is hoped that the NSRP will
actively contribute to making overall policies and plans for the ITER Project and BA
activities in the future.
[４] Human resources development
Does the NSRP contribute to the development of human resources required formaintaining high-level simulation research activities toward the future?
The NSRP is accepting graduate students from universities such as the Graduate
University for Advanced Studies and Nagoya University, and developing young humanresources through cooperation with Asian Winter Schools and high schools designatedas SSH. It can be highly evaluated that the NSRP contributes to the nurture of young
domestic and foreign researchers in addition to young staff members at NIFS throughthe achievement of developing multi-scale simulation codes systematically to date.
On the other hand, it is desirable to develop an organizational strategy for humanresource development, including career path formation, and to promote personnel plansand personnel exchanges with a view to continued development in the future.
[５] Future planIs the future research plan suitable for progressing toward the goal of the NSRP?
Does it also contribute to establishing the future plan of the National Institutefor Fusion Science?

- 10 -

Research on the validity and applicability of theoretical and numerical models has
been steadily conducted so far and roadmaps for each of the eight task groups areformulated for advancing research toward the goal of the NSRP. In addition, it is highly
evaluated that the NSRP plays a major role in establishing the future plan of NIFS,
including the next-generation device.
On the other hand, it is necessary to further develop future plans and set researchgoals by clarifying development issues for the realization of the Numerical Simulation
Reactor, roadmaps for each task group, and efforts toward the code integration. It is also
desirable to actively discuss collaboration among the task groups and experimental
projects and to examine top-down promotion regarding the issues required to achieve thegoal of the NSRP.
［２］Recommendations

In the present evaluation, we discussed the Numerical Simulation Reactor Research Project (NSRP)
in NIFS. Based upon the contents of the discussion, we describe the recommendations regarding thefuture plan of the Numerical Simulation Reactor Research Project below.
（1）

As one of the major research projects in NIFS, the Numerical Simulation Reactor Project

has been conducting distinguished studies and playing an important role in all facets of fusion
research. While maintaining and developing the route of research that has contributed to progressin a wide range of simulation sciences, collaborations among the task groups and other institutes
should be planned so as to constantly create new research themes based on flexible ideas. It is
desired that fulfillment of the management system and allocation of the resources are made basedon constant check and evaluation for construction of the Numerical Simulation Reactor.
（2）

It is hoped that NIFS will aim for leadership in interdisciplinary research based on the

Numerical Simulation Reactor Research, pursuing impactful innovations such as hierarchicalintegration in the entire field of simulation science.
（3）

The simulation science research environment in NIFS is one of the foundations forpromoting plasma and nuclear fusion research throughout Japan. It is necessary to plan andimplement installation / maintenance of supercomputers and enhancement of the support system
at appropriate times in the future, incorporating the opinions of collaborative researchers andinstitutions.

- 11 -

（4）The role of NIFS as a center of collaborative research is crucial, and its active contribution

to strengthening the competitiveness of universities is desired in addition to conducting the
project. From the viewpoint of academic systematization, further enhancement of international
collaboration and commitment to organized dissemination activities are desired in order to link
the achievements in the NSRP to the construction of universal science and make the excellent
developed codes be used as international standards.
（5）

For continuous development of the research field, it is hoped that personnel planning andpersonnel exchange will be actively promoted with a view to the future of the Numerical
Simulation Reactor Research. Systematic efforts are desired for development of a wide range ofhuman resources in the fields of theory and simulation including career path formation.

- 12 -

Chapter 3 In Closing
Since 2010, in order to further strengthen the centripetal power of NIFS as a COE in the fieldof plasma and fusion research we have organized three research projects, these being LHD, theory andsimulation, and reactor engineering. Looking forward toward achieving the fusion reactor, NIFS has
initiated research programs that will integrate these research results. Moreover, the research structure
at NIFS was reorganized and all academic researchers have now been placed in one research
department. They may now participate in any or all of the three research projects by their choice. Dueto this, we anticipate the promotion of links with LHD, theory and simulation, and fusion engineering,
and we anticipate being able to respond resourcefully to new topics.
In the NIFS External Peer Review Committee review, in 2016 the Collaborative Research,
in 2017 the Reactor Engineering Research Project, and in 2018 the LHD Project were evaluated. Thus,in this current year of 2019 the Advisory Committee undertook an external evaluation that focused on“The Numerical Simulation Reactor Research Project.” The External Peer Review Committee wascomposed of 10 members of the Advisory Committee outside of NIFS and three members from abroad,and, as the experts, three members outside of NIFS.

Evaluation items in FY2019 External Peer Review
1. Development of research plan, system, and environment（1） DoestheNumerical

Simulation

ReactorResearch

Project(NSRP)

appropriately set the goal and plan including the roadmap for construction of
the Numerical Simulation Reactor? Are they properly discussed foraccomplishing the third midterm target and plan?
（2） Does the research system function appropriately in accomplishing theobjectives of the NSRP with attention to the management of step-by-step progress,
research collaboration, and integration?
（3） Is the environment of the “Plasma Simulator” system and its related research
appropriately developed and effectively utilized according to the research plan?
Is the installation of a higher performance supercomputer properly planned?
2. Research achievements
Does the NSRP produce high-level achievements in accordance with international
standards for the following research areas described in the third midterm goal andplan by promoting theory and computer simulation research utilizing the Plasma
Simulator?
（1） Constructionofthe Numerical- 13 -

Simulation

Reactor,Validationandimprovement of simulation codes through comparison to experimental results（2） Academic systematization of fusion science, related science, and engineering（3） Are research achievements steadily made according to the plan of the NSRP?
3.Promotion of cooperation and collaboration（1） Is collaboration research with universities based on theory and simulation
research appropriately promoted?

Does it contribute to the progress of the

NSRP?
（2） Does the NSRP contribute to enhancing functions of universities andinstitutes as the center of excellence for fusion plasma simulation? Does the
NSRP commit to the promotion of interdisciplinary collaboration and research?
（3） Does the NSRP contribute to international cooperation including ITER, BA
activities, and others through international collaboration activities?
4.Human resources development（1） Does the NSRP contribute to the development of human resources required
for maintaining high-level simulation research activities toward the future?
5.Future plan
（1） Is the future research plan suitable for progressing toward the goal of the
NSRP? Does it also contribute to establishing the future plan of the National
Institute for Fusion Science?

The External Peer Review Committee was convened four times from October 2019 throughFebruary 2020 including the e-mail discussion committee. Detailed explanations of the evaluation
topics were provided from NIFS and active discussions were held. The External Peer Review
Committee members summarize evaluation results based on discussion at the committee and submit
this report.
As the result of the external evaluation of the “Numerical Simulation Reactor Research
Project, (NSRP)” in general, a recommendation of a high evaluation are received for the above
evaluation points. Especially, development and improvement of simulation codes toward
construction of the Numerical Simulation Reactor are highly evaluated observing the steadyprogress in which numerous remarkable research results were produced from the organization of task
groups. In addition, as one of the major research projects in NIFS, the NSRP has been appropriately- 14 -

developing the simulation research environment including the “Plasma Simulator” and making
sufficient efforts to maximize the research achievements. The NSRP have been actively promoting
collaboration research, striving for construction of an excellent support system, andmaking a significant contribution to the academic progress of the entire researchcommunity as the Inter-University Research Institute.
It is desired on the other hand that the roadmap for the construction of the Numerical
Simulation Reactor is appropriately reviewed according to the research progress, and new scientificsubjects are challenged for the further development of the NSRP and pioneering new academic fields.
Furthermore, it is hoped that, as a center of collaborative research, the NSRP actively and initiatively
conducts high-scholarly-valued studies and takes leadership in academic research while promotinginternational and interdisciplinary collaborations.

In conclusion, we suggest the following recommendations regarding the future plan of the
Numerical Simulation Reactor Research Project (NSRP).
（1）

As one of the major research projects in NIFS, the Numerical Simulation Reactor Project

has been conducting distinguished studies and playing an important role in the entire fusion
research. While maintaining and developing the route for research that has contributed to theprogress in a wide range of simulation science, collaborations among the task groups and otherinstitutes should be planned so as to constantly create new research themes based on flexible
ideas. It is desired that fulfillment of the management system and allocation of the resources are
made based on constant check and evaluation of construction of the Numerical Simulation
Reactor.
（2）

It is hoped that NIFS will aim for leadership in interdisciplinary research based on the

Numerical Simulation Reactor Research, pursuing impactful innovations such as hierarchicalintegration in the entire field of simulation science.
（3）

The simulation science research environment in NIFS is one of the foundations to promote

plasma and nuclear fusion research throughout Japan. It is necessary to plan and implement
installation / maintenance of supercomputers and enhancement of the support system atappropriate times in the future, incorporating the opinions of collaborative researchers andinstitutions.
（4）

The role of NIFS as a center of collaborative research is crucial, and its active contribution

to strengthening the competitiveness of universities is desired in addition to conducting the- 15 -

project. From the viewpoint of the academic systematization, further enhancement ofinternational collaboration and commitment to organized dissemination activities are desired inorder to link the achievements in the NSRP to the construction of universal science and make theexcellent developed codes be used as international standards.
（5）

For continuous development of the research field, it is hoped that personnel planning andpersonnel exchange will be actively promoted with a view to the future of the Numerical
Simulation Reactor Research. Systematic efforts are desired for development of a wide range ofhuman resources in the field of theory and simulation including career path formation.

- 16 -

Documents

1. 2019 External Peer Review Presentation Materials

Overview of Numerical Simulation
Reactor Research Project
Hideo Sugama, Yasushi Todo,
Seiji Ishiguro, and NSRP Members
National Institute for Fusion Science

1/196

Outline
1. Research plan, system, and environment
2. Research achievements
3. Promotion of cooperation and collaboration
4. Human resources development
5. Future plans

2/196

1. Development of research plan, system and environment(1) Does the Numerical Simulation Reactor Research Project (NSRP)
appropriately set the goal and plan including the roadmap forconstruction of the Numerical Simulation Reactor? Are they properly
discussed for accomplishing the third midterm target and plan?
(2) Does the research system function appropriately in accomplishing theobjectives of the NSRP with attention to the management of step-bystep progress, research collaboration, and integration?
(3) Is the environment of the “Plasma Simulator” system and its related
research appropriately developed and effectively utilized accordingly tothe research plan? Is the installation of a higher performancesupercomputer properly planned?
Presentation by H. Sugama (1)3/196

2. Research achievements

Does the NSRP produce high-level achievements in accordance withinternational standards for the following research areas described in thethird midterm goal and plan by promoting theory and computer simulation
research utilizing the Plasma Simulator?
(1) Construction of the Numerical Simulation Reactor, Validation andimprovement of simulation codes through comparison toexperimental results

Presentation by Y. Todo

(2) Academic systematization of fusion science and related science andengineering

Presentation by S. Ishiguro(3) Are research achievements steadily made according to the plan of the
NSRP?

Presentation by H. Sugama (2)4/196Presentation by H. Sugama (3)3. Promotion of cooperation and collaborations(1) Is collaboration research with universities based on theory and simulation
research appropriately promoted? Does it contribute to the progress of the
NSRP?
(2) Does the NSRP contribute to enhancing functions of universities andinstitutes as the center of excellence for fusion plasma simulation? Does
the NSRP commit to the promotion of interdisciplinary collaboration andresearch?
(3) Does the NSRP contribute to international cooperation including ITER, BA
activities, and others through international collaboration activities?

4. Human resources development(1) Does the NSRP contribute to the development of human resources required
for maintaining high-level simulation research activities toward the future?

5. Future plan
(1) Is the future research plan suitable for progressing toward the goal of the
NSRP? Does it also contribute to establishing the future plan of the
National Institute for Fusion Science?
5/196[1]-(1)6/196

1. Development of research plan, system, and environment(1) Does the Numerical Simulation Reactor Research Project (NSRP) appropriately
set the goal and plan including the roadmap for construction of the Numerical
Simulation Reactor? Are they properly discussed for accomplishing the third
midterm target and plan?
(2) Does the research system function appropriately in accomplishing the objectivesof the NSRP with attention to the management of step-by-step progress, researchcollaboration, and integration?
(3) Is the environment of the “Plasma Simulator” system and its related research
appropriately developed and effectively utilized accordingly to the research plan?
Is the installation of a higher performance supercomputer properly planned?

The goal of the NSRP is
to construct the Numerial Simulation Reactor (next page) andto systematize and develop nuclear fusion science and related scienceand engineering through collaboration with universities and research
institutes (third midterm target) .
7/196

Numerical Simulation Reactor
A system of simulation codes to predict behaviors of fusion plasmas over thewhole machine range
Plasma Simulator

3D large-scale simulation of fusion system

First principle simulation codes
Provide modules
using reduced models
or directly coupled

Analysis & prediction ofexperimental results

Validation bycomparison withexperiments

Integrated code (TASK3D)
Modules
3D equlibrium
Transport (NCL, turb)
Heating (NBI, ECH,…)
Neutral particles

TASK3D-a(analysis)
TASK3D-p(prediction)

Prediction of plasma behaviors
in a whole machine range

Plasma simulator
2.6PF (2015)

Optimization ofmagnetic
configuration
Contribution to
Designing highperformancehelical reactor

Collaboration withexperiment &engineering groups

…………

8/196

Third Midterm Target and Plans
Third Midterm Target of NIFS (FY2016-2021)
As a COE of nuclear fusion science research in Japan,
NIFS aims to systematize and develop nuclear fusion
science and related science and engineering throughcollaboration with universities and research institutes.
To realize controlled thermonuclear fusion with excellent
environmental safety, NIFS promotes joint researches inJapan using a large experimental device and asupercomputer as well as supporting burning plasma
experiments through international collaboration.

9/196

Third Midterm Plan of NSRP (FY2016-2021)

skip[Means to achieve the target related to levels and results of research]
Effectively using the supercomputer system, Plasma Simulator, for construction of
the Numerical Simulation Reactor, we advance the researches for thedevelopment, the extension, the high precision, and the integration of thesimulation codes for the whole device from the core plasma to the peripheral
plasma and plasma facing wall.
During FY2019, we improve the performance of the Plasma Simulator more thanfour times compared to the current system, and optimize various threedimensional simulation codes for the improved system.
In addition, modeling of turbulent transport in core plasma and the application of
the model into the integrated transport code are to be completed by the end of
FY2019, and the incorporation of multiple ion species effects into varioustransport codes is to be done by the end of the third mid-term target period.
Furthermore, by the end of the third mid-term target period, molecular dynamics
simulation techniques are developed by improving programs and building newmodels necessary for evaluating the physical properties of plasma facing
materials such as tungsten.
Simultaneously, as supporting research to achieve the above goals, we improvethe code accuracy by comparison with the experimental results on the threedimensional equilibrium, transport, instability and nonlinear evolution ofmagnetically confined plasmas including LHD plasmas while conducting
simulation researches on related basic physics.

10/196

Third Midterm Plan of NIFS (FY2016-2012)

skip[Means to achieve the target related to contents and levels of joint use andresearch]
Deuterium plasma experiments using LHD, large-scale simulations using Plasma
Simulator, and reactor engineering researches utilizing large test facilities are
conducted as advanced joint use and joint research through domestic andinternational collaborations.
NIFS aims to improve the quality of domestic collaborations and to increase theopportunities for international collaborations.
NIFS contributes to the creation of research results from universities by leadingcollaborative research using inter-university networks such as interactive joint
research as part of the Institute for Promotion of Inter-University Collaboration(tentative name).
For collaborative projects based on bilateral and multilateral agreements, we
focus on research plans within a limited budget and aim for higher results.
With respect to international projects such as the International Thermonuclear
Experimental Reactor (ITER), NIFS plays a role of COE to further collaborate with
universities under cooperation agreements in areas where NIFS has specialties.
In order to sustain the function of NIFS as the Inter-University Research Instituteat a high level, the joint use rate of LHD and Plasma Simulator are maintained at100%.
11/196

Third Midterm Plans of NSRP

•
•
•

•

•

Effectively use Plasma Simulator for construction of the Numerical
Simulation Reactor to advance the researches for the development,
the extension, the high precision, and the integration of the 3D
simulation codes
Model turbulent transport in core plasma and apply the model into
the integrated transport code by the end of FY2019
Incorporate multiple ion species effects into various transport codes
Develop molecular dynamics simulation techniques and build newmodels necessary for evaluating physical properties of plasma facing
materials such as tungsten
Improve the code accuracy by comparison with the experimental
results on the three-dimensional equilibrium, transport, instability andnonlinear evolution of magnetically confined plasmas including LHD
plasmasConduct simulation researches on related basic physics
Promote domestic and international collaborations including ITER
Improve the performance of the Plasma Simulator more than fourtimes compared to the current system during FY2019
Maintain the joint use rate Plasma Simulator at 100%.

12/196

Three-step plan of the NSRP:
1.
2.
3.

To develop simulation codes for various physics elements of fusion plasmas
To integrate and validate simulation codes for treating multi-scale and multiphysics phenomena
To construct a system of codes [=Numerical Simulation Reactor (NSR)] forcontributing to designing high-performance helical fusion reactor

Roadmap for realizing Numerical Simulation Reactor (NSR)
2nd mid-term

3rd mid-term

4th mid-term

2010

2016

2022

2028

Development ofsimulation codes
for various physics
elements
constituting fusion
plasmasExtension and integration ofcodes for treating multi-scale
and multi-physics phenomena
V&V and application of codes
by collaboration withexperiments and engineering

Further development
and completion of
NSR for contributing
to designing highperformance helicalfusion reactor

2019

13/196

Research Plan of NSRP (1)4th mid-term

3rd mid-term

2028

2022

2019

2016
Equilibrium& MHD

Include flow effects on
equilibrium & stability

HINT2, MINOSMIPS, NORM
CAP

Studies on next generation device design

Anisotropic pressure effects
Quasi-interchange modes

D shape effects

Optimazation, divertor field line calculation
for helical & modular coil sytems

Combining codes to study kinetic
effects on stability
Kinetic thermal ion
effects on stability

Energetic
Particle
MEGA

Kinetic thermal ion effects
on nonlinear evolution

Thermal &energetic ion
effects

Studies on EP driven instabilities
EP driven AE burst
EGAM in 3D equlibrium

AE with ICRF

AE & ITG & ZF

EP driven interchange modes (EIC)NBI (GNET, collaboration
with Kyoto Univ)

ICRF fast ions

Reduce EP
transport model

V&V on CFQS

V&V on LHD experiments
V&V on DIIID, JT60U

V&V on JET DT

Integrated analysis for reactor design

Pellet, plasmoid analysis
Studies on LES of Extended MHD

V&V on JT-60SA
14/196

Research Plan of NSRP (2)4th mid-term

3rd mid-term

2028

2022

2019

2016
Core
transport

Large-scale NCL & GK simulation studies
Global NCL simulation for multi-ion-species plasmas
Interaction of NCL &Global GK simulation

GKV+
FORTEC-3D
GT5D
XGC-S

V&V studies of NCL & GK simulations against experimental results
Studies on impurity hole in LHD
Studies of isotope effects on turbulent transport in LHD

turbulent transport

Kinetic transport modeling for applying to integrated
simulations and next generation device design
Applying Turbulent ci & ce models
Including E shear,

Integrated
transport
codermulti-species, global
effects

Integrated analysis forreactor design

Construction and application of QL
models of Ge, qe & qi

Analytical suite (TASK3D-a) for validation against LHD deuterium experiments
NBI modules for deuterium experiments
Coupling to large-scale simulation codes(FORTEC-3D, PENTA, SFINCS, GKV-X)
Analysis of energetic particles, impurities, isotope effects

TASK3D

Predictive suite (TASK3D-p) for steady-state high-performance LHD and
FFHR design study
Consolidation of GNET for NBI
heating analysis
Transport model including GyroBohm with Zeff, Aeff effects

FFHR-d1 start-up to whole-duration siulation
Comparison among transport models
Data assimilation

15/196

Research Plan of NSRP (3)4th mid-term

3rd mid-term
Peripheraltransport
EMC3-EIRENE

2028

2022

2019

2016

Development and validation of 3D edge transport code
Impurity seeded plasma modeling & validation with LHD experiments
Detach modeling of NAGDIS-II
Hydrogen molecule
atomic process
Erosion-transport-redeposition modeling of LHD
Bolometer data analysis

Studies on divertor modeling / plasma-wall interaction / dust dynamics
Dust transport in LHD
Modeling for JT-60SA: RMP,
Heliotron J
NAGDIS-II

toroidal coil modulation,

validation

EAST

Next generation device: divertor concept,
FFHR

Plasmawall
interaction
GLIP, AC∀T
OpenMX

transport,

Studies on tungsten divertor physics
Fuzz formation
BCA-MD-KMC simulation
Hydorgen recycling model (MD)Graphite

Structure change under irradiation
New divertor physics
TungstendesignExtension ofmulti-hybrid
simulation
Other materials

Studies on radioactive material: Tritium disintegration effect on
biopolymers
MD modeling of DNA
disintegration by tritium

Integrated analysis forreactor design

Transport modeling for optimized divertor

Extension to other bases of DNA or proteins

16/196

[1]-(2)17/196The NSRP performs its research activities in synergyskip
with other projects under the framework of the
NIFS research system•[Research system] Research divisions are the warp of the research while theprojects are the weft. Both are woven together to achieve the goal.
Department and Project
The seven divisions of the Department of
Helical Plasma Research vertically divide
research staff and three projects assign
them horizontally across sectional borders.

Numerical Simulation Reactor Research Project

18/196

1. Development of research plan, system, and environment(2) Does the research system function appropriately in accomplishing the objectivesof the NSRP with attention to the management of step-by-step progress, researchcollaboration, and integration?

The research system of the NSRP is organized as shown below to
enable flexible management of step-by-step progress, researchcollaboration, and integration of activities of 8 NSRP task groups,
other NIFS Projects, and collaborators from outside of NIFS.

GeneralMeeting

19/196The eight task groups are organized to cover a wide
range of fusion simulation subjects
group

leaderPlasma fluid equilibrium stability
Energetic-particle physics
Integrated transport simulation

member

K. Ichiguchi

13（sim. 7, exp. 3, collab. 3）

Y. Todo

9 （sim. 4, exp. 3, collab. 2）

M. Yokoyama 28（sim. 4, exp. 13, collab. 11）

Neoclassical and turbulent transport
simulaton

R. Kanno16（sim. 8, exp. 3, collab. 5）

Peripheral plasma transport

Y. Suzuki

20（sim. 4, exp. 5, collab. 11）

Plasma-wall interaction

H. Nakamura

18（sim. 4, exp. 3, collab. 11）

Multi-hierarchy physics

H. Miura

18（sim. 12, collab. 6）

Simulation science basis

H. Ohtani

16（sim. 12, exp. 1, collab. 3）

Sim.: simulation staff, exp.:experiment staff, collab.:domestic collaborators••

Many collaborators from other projects and from outside NIFS have joined thesetask groups to enhance collaboration and cooperation studies.
Most of the simulation staff in the NSRP also participate in other task groups.
20/196

Steering Committee consists of the executive director, two division directors, and task group leaders.
The meeting is periodically (once a month) held to manage the NSRP activities to function
appropriately as a whole.
Step-by-step progresses are checked and saved in a File of Milestones.
General Meeting is held once a month, and is chaired by group leaders in rotation,enhances fast and smooth communication among all NSRP members.
Joint research activities , progresses, and information related to NSRP and PS are discussed.
Publishments of research results and presentations in international conferences are checked.
Plasma Simulator (PS) Working Group consists of a Leader and five members,
manages and operates PS and LHD Numerical Analysis Server in collaboration with Fujitsu systemengineers.

GeneralMeeting

21/196

Progress of NSRP, Inter-Project collaboration, andjoint researches based on Plasma simulator arechecked with domestic collaborators• Meetings to report results of NSRP
• Meeting to report results of all three Projects (in June ):Progress of three Projects made in the past year are checked withdomestic collaborators.
• Plasma Simulator Symposium (in September):
Results from PS joint researches are checked and PS operation
management is discussed.

• Inter-Project collaboration• Validation of simulation results is done in comparison with resultsfrom LHD experiments in collaboration with the LHD Project.
• Predictions of performance of FFHR are made in collaboration with
the Fusion Engineering Project.
• Contributions to optimization and design studies of highperformance helical devices are made. (→ Chap.6)

22/196

[1]-(3)23/196

1. Development of research plan, system, and environment(3) Is the environment of the “Plasma Simulator” system and its related research
appropriately developed and effectively utilized accordingly to the research plan?
Is the installation of a higher performance supercomputer properly planned?

(1) The computer system Working Group manages and operates the
Plasma Simulator and LHD Numerical Analysis Server in collaboration
with Fujitsu system engineers (since June 1, 2015) to make theresearch environment function appropriately.
(2) More than 50 projects each year are performed as Plasma Simulator
Collaboration Research.
(3) The research for upgrading Plasma Simulator has been properly
conducted and the installation of a higher performancesupercomputer is to be completed by June 2020 (one year behind theschedule in the midterm plan).
(4) Virtual-reality (VR) system “CompleXcope” was upgraded.
24/196

“Plasma Simulator” is going to be upgraded to a new system:

total peak performance more than 10 Petaflops in June 2020
Plasma Simulator is going to
be replaced to a new system inJune 2020.
The peak performance of the
new PS system is more than fourtimes of the current FX100
system (to be operated until theend of Feb. 2020.)

HITACHI SR16000/L2(peak speed:77TF
memory: 16TB
period: 2009 – 2012)

HITACHI
SR16000/M2(peak speed: 315TF
memory: 40TB
period: 2012 –2015)

FUJITSU PRIMEHPC FX100(peak speed: ~2.6PF memory:~81TB
period: 2015-2020)

NEC (model name TBD)
(peak speed:~10.5PF,
memory:~200TB: period:2020-2025)

Peak performance (Tflops)
10000
1000
100
10
1
0.1
0.01
0.001

25/196The “Plasma Simulator” system has been developed andperiodically upgraded for the NSRP
• Phase 1 (March 2009 – August 2012): HITACHI SR16000 model L2, with 128 nodes• Phase 2 (October 2012 – March 2015): HITACHI SR16000 model M1, with 322 nodes• June 2015 – Feb 2020: FUJITSU PRIMEHPC FX100 with 2592 nodes• June 2020 – May 2025: NEC (model name TBD) with 4320 VE,
VE = Vector Engine (accelerator), 2.433 Fflops, 48GiB memory for each VE.
Peak
Performance

MemoryStorage

HITACHI SR16000
model L2 (Phase 1)

77 TFlops

16 TB

0.5 PBHITACHI SR16000
model M2 (Phase 2)

315 TFlops

Figure 1

40 TB

2.0 PB

FUJITSU FX-100

2.62 PFlops

81 TB

10.0 PB

NEC (model name
TBD)

10.5 PFlops

202TB(VE part)

32.1 PB

skip

FUJITSU PRIMEHPC FX100 in NIFS

• Plasma Simulator was ranked for 65th in the world (7th in Japan) in June 2009, 96th (8th inJapan) in Dec. 2012, and 27th (3rd in Japan) in June 2015 on the “TOP 500 LIST”.
• PS was ranked12th in the world (2nd in Japan) on the “High Performance Conjugate
Gradients (HPCG)” in June 2015, too.
26/196

Virtual-reality (VR) system “CompleXcope” wasupgraded and head-mount display (HMD) was set up.
• Since Plasma Simulator was upgraded, it was expected that the size ofsimulation data increased explosively. High-spec computer systems (Linuxand PC cluster) and higher brightness projectors were installed for analysis
of such large-scale simulation data in VR space.
• A head-mount display was also set up for another visualization method.
• A game development engine “Unity” was installed as a common
development environment.

• It is expected that larger size simulation results can be analyzed in VR
space.
• We can build easier VR develop environment by using Unity to make VR
visualization software for CAVE, HMD, and so on.

27/196More than 50 projects every year were performed as
Plasma Simulator Collaboration Research
FY

Collab.
Research
Projects

Users(NIFS/Univ.)

Simulation Jobs

2012

56

169 ( 50/119)

16,6842013

51

158 ( 50/108)

19,5482014

53

162 ( 50/112)

21,540

50

2015

60

154 ( 49/105)

46,078

30

2016

65

184 ( 50/134)

70,041

10

2017

67

194 ( 45/149)

90,7302018

68

194 ( 50/144)

96,7962019

68

183 ( 54/129)

31,407 (Apr.-Sep.)

Rate of operation in PS (%)
100
90
80
70
60
40
20
0
2012

2012

2013

2014

2015

2016

2017

2018

(Apr.- (Oct.Aug) Mar.)2019(Apr.Sep.)

Year• There are about 160-190 users each year with 60 or less from NIFS and 105-149
or more from universities.
• More than 90,000 jobs are run on Plasma Simulator in recent years.
• The average operating rate (ratio of successful computations to the total machine
28/196time) is 80-90%.

The computer system Working Group manages and skip
operates Plasma Simulator and LHD Numerical Analysis
Server in collaboration with FUJITSU system engineers• Tasks• user registration, computer resources allocation, operation scheduling• management of hardware and software troubles• web site (figure): user manual, Q&A, text of user course, etc.
• Operation meeting is held every month to grasp and resolve issues.

29/196

Research assistance system has been developed forcollaboration studies in the NSRP
• User course is held at the beginning of each fiscal year regarding• how to use the Plasma Simulator and the LHD Numerical Analysis Server• program tuning (code optimization)• OpenMP and MPI (parallel computing)skip• AVS/Express (scientific visualization)• Three system engineers from Fujitsu corporation are permanently working in the
Program Development Support Office in NIFS
• one engineer for operation support• two engineers for users’ program development support• In response to users’ requests and questions, program development support
engineers assist users in:• optimizing programs on FX100• parallelizing programs with SMP (auto parallelization), OpenMP and MPI• finding unexpected/invisible troubles in simulation codes• 158 cases, including 28 cases from universities, have been assisted for program
development support since March 2009.

30/196

[2]-(1)31/196

2. Research achievements

Does the NSRP produce high-level achievements in accordance withinternational standards for the following research areas described in thethird midterm goal and plan by promoting theory and computer simulation
research utilizing the Plasma Simulator?
(1) Construction of the Numerical Simulation Reactor, Validation andimprovement of simulation codes through comparison toexperimental results

Presentation by Y. Todo

(2) Academic systematization of fusion science and related science andengineering

Presentation by S. Ishiguro(3) Are research achievements steadily made according to the plan of the
NSRP?

Presentation by H. Sugama (2)32/196

2. Research achievements

Does the NSRP produce high-level achievements in accordance with international
standards for the following research areas described in the third midterm goaland plan by promoting theory and computer simulation research utilizing the
Plasma Simulator?
(1) Construction of the Numerical Simulation Reactor, Validation andimprovement of simulation codes through comparison to experimental
results

The NSRP produces a large number of high-level achievements in theory andsimulation research for construction of the Numerical Simulation Reactor.
• Development, coupling, and integration of various simulation codes, whichconstitute the Numerical Simulation Reactor, have progressed.
• Validations of codes by comparisons with experiments in LHD and otherdevices have progressed.
• These simulation codes contribute to numerous analyses of fusion
plasmas in LHD and other devices as well as to predictions of FFHR plasma
performance (and optimization of magnetic configuration → Chap.6).
33/196

Extensive simulation code developments andcomparisons between simulation and experiments havebeen performed
MIPS, MUTSU/MINOS
Nonlinear MHD

EMC3-EIRENE (Max-Planck IPP)
Edge plasma(Kyoto Univ)

34/196

Simulation researches toward construction of
the Numerical Simulation Reactor• Integration of MHD and energetic particle simulations• Neoclassical and turbulent transport
Modeling of turbulent transport for integrated code simulation• Integration of peripheral transport and PWI simulation• Integrated code
Application to analysis and prediction of experiments
Contributions to fusion reactor design
35/196Integration of MHD and energetic particle simulations,and the validation for construction of the Numerical Simulation Reactor• 3D MHD equilibrium, effects of plasma flow on interchange modes,
nonlinear evolution of ballooning modes, and pellet injection with magnetic
islands for LHD plasmas• Extension of the EP-MHD hybrid code MEGA towards the integration of
MHD and EP simulations• Energetic particle driven geodesic acoustic mode and energy channeling tothermal ions
• Comprehensive simulations of energetic-particle (EP) driven instabilities
with beam injection and collisions• Full PIC simulation of high-frequency energetic-ion driven instabilities andtime-dependent plasma heating analysis

36/196

Impacts of plasma beta and toroidal current density
are studied by 3D equilibrium calculation code HINT
• For current-free case, 5/6 islands vanish (self-healing), 10/12 islands
become visible.
• But, for bootstrap current included, islands at boundary appears, but thoseare smaller than vacuum islands.
Current-freeWith bootstrap current

skip• To control divertor islands, active control, which are planar coils, sweep
coils, will be necessary.
37/196

3D flow mapping from 1D experimental data skip
• FLOWVM code is developed.
• The global flow is calculated with the the VMEC equilibrium and 1D experimental
data.

• The flow data in the whole plasma region can be obtained.
• This code gives a mapping of the 1D data to the 3D region.
38/196

Causality between the fluctuation excitation and themode rotation stopping is analyzed with transfer
entropy.
• Causality can be analyzed by means of the transfer entropy.
• This technique is applied to the magnetic fluctuation excitement and themode rotation stopping in the collapse observed in the LHD experiments.
br11
f11

m/n=1/1

2

1

1
0

0
4.0

4.2

4.4

time (sec)

4.6

-1

frequency (kHz)

br/BT

1.0

3

-3

Transfer Entropy[ 10 ] 2

0.8

f11 -.> Br11

skip

Br11 -> f11

0.6
0.4
0.2
0.0
0

0.1

0.2
0.3
0.4
Time Lag (sec)

0.5• It is obtained that the information is transferred from the rotation frequency
to the magnetic fluctuation and the information is not transferred in the
opposite direction.
• This result suggests that the rotation stopping caused the fluctuation
excitement.

39/196The ballooning modes destabilized in the peripheral
region can lead the core crush.
[ M. Sato, N. Nakajima, K. Watanabe, Y. Todo, Nucl. Fusion (2017) ]• The nonlinear evolution of resistive ballooning modes in high beta LHD plasmas
has been investigated by MIPS code.

Time evolution of the radial spectral
distribution of the perturbed pressure.
• Low toroidal modes typified by the n=1 mode are nonlinearly generated byresistive ballooning modes with n〜10 destabilized in the peripheral region.
• The self mode coupling of the low n modes induces the core crush.

40/196

Stabilizing window appears in background shear flow.
• The calculation scheme of 3D background flow consistent with 1D
experimental data is established.
• Nonlinear interaction between the interchange modes and the backgroundglobal flow is numerically studied in LHD plasmas with the MIPS code.

• The effects of the global flow on the interchange modes are analyzed byincreasing the flow velocity amplitude.
• The flow stabilizes the interchanged mode up to 10 times larger than theobserved value, however, the flow destabilizes the Kelvin-Helmholz mode
beyond 30 times larger than the observed value.

41/196

MHD simulations of the pellet injection in LHD plasmas
with and without islands have been performed.

skip• MHD simulations including the ablation processes have been performed with
CAP code.
TC: thermal conduction
Densityw/ island

Pressure

Ablation rate

w/ island

Ablation rate

w/o island

w/o island

w/ TC
w/o TCw/o TC

w/ island

w/ TC
w/o island• The ablation rates are different between in LHD plasmas with and withoutislands due to the difference of the electron temperature. The density peak islocated in the vicinity of the o-point in the plasma with the island.
• The ablation pressure increases because no diffusion occurs in the casewithout the thermal conduction. In result, since the pressure gradient increases,
the density decreases due to the elongation of the plamoid along the field line. 42/196

Integration of
MHD and
Energetic Particle
Simulations
43/196

Precession drift motion of trapped thermal ionssuppress the ballooning modes in LHD plasmas.
[ M. Sato and Y. Todo, Nucl. Fusion (2019) ]• Effect of the thermal ions on the resistive ballooning modes in the LHD plasmas
has been investigated by MEGA code based on the kinetic MHD model.

• The response of the trapped ions to the MHD instability is weakened by thepoloidal precession drift motion of the trapped ions.
• This results in the suppression of the ion perpendicular pressure perturbation
44/196to the magnetic field leading to the reduction of the linear growth rate.

The kinetic-MHD hybrid code MEGA was extended tosimulate kinetic thermal and fast ions
• The PIC simulation is applied to both thermal and fast ions.
• The time evolution of an Alfvén eigenmode was compared between bulk plasma
beta 1% and 4%.
Invited talk at EPS (2019)skip

βbulk0=4%

βbulk0=1%• It wasdemonstrated thatthe saturation levelof a toroidal Alfvén
eigenmode is
reduced for higher
bulk temperature.

• The reduction ofsaturation levelcan be attributed tothermal ion Landau
damping.

V=0.2VA

V=0.1VA

45/196

Nonlinear evolution of EP driven geodesic acoustic
mode and energy channeling were clarified• Chirping energetic-particle driven geodesic acoustic mode (EGAM) and thesudden excitation of a half-frequency EGAM were reproduced with the MEGA
code for a 3D LHD equilibrium. [Wang+(PRL2018)]• The simulated results including mode numbers, frequencies, profiles, andphase relations, are in very good agreement with experimental measurements.
• The excitation mechanism of the half-frequency EGAM was clarified.
experiment

40
20

simulation

E [J]

0

simulation

-20
-40
EP
ion
e

-60
-80
0

0.1

0.2
t [ms]

0.3

0.4• The bulk ions are kinetically modeled, and the EGAM channeling in LHD was
successfully simulated. [Wang+(NF2019)]• The sideband resonance plays an important role in bulk ion heating.

46/196

Fast-ion profile stiffness with increasing beam power• Sudden increase in Alfvén-eigenmode-induced fast-ion transport withincreasing beam power observed in DIII-D experiments is reproduced bycomprehensive kinetic-MHD hybrid simulations.
• Resonance overlap of multiple eigenmodes accounts for the sudden increasein fast ion transport with increasing beam power.
PNBI=1.56MW

PNBI=3.13MW

PNBI=6.25MW

PNBI=15.6MW[Todo+(NF2016)]

NF Highlights of 201647/196

Critical energetic particle distribution in phase space for the
Alfvén eigenmode burst with global resonance overlap• Comprehensive computer simulations of the Alfvén eigenmode (AE) bursts.
• Energetic-particle distribution in phase space reaches a ‘critical distribution’with a stairway structure just before the AE burst.
• When the distribution reaches the ‘critical distribution,’ a resonance overlap
triggers multiple resonance overlaps leading to the synchronized growth of
AEs and the collapse of the distribution.

Oral presentation at IAEA (2018) [Todo (NF2019)]

48/196

Alfvén eigenmode bursts in LHD experiments were
simulated with the kinetic-MHD hybrid code
• Alfvén eigenmode bursts in the LHD experiment #47645 were simulated with therealistic NBI deposition profile and collisions of fast ions with the bulk plasma.
• The Alfvén eigenmodes (AEs) and the alternate growth of the two AEs in thesimulation were consistent with the experiment.
52kHz GAE

skip

78kHz TAE

r/a=0.73

72kHz TAE

shear Alfvén continuous spectra

r/a=0.34[Todo+(PoP2017), Seki+(NF2019)]

49/196

Full PIC simulations of energetic-ion driven instabilities nearlower hybrid resonance frequency have been performed• PIC simulation with full ion and electron
dynamics have shown that energetic
ions with a ring-like velocity distribution
excite waves with frequencies near the
lower-hybrid resonance frequency ωLH,
in addition to ion cyclotron wave and its
harmonics.
[Toida+(PFR2018)][Toida+(PFR2019)]• Instabilities driven by energetic ions injected
continuously in a plasma with increasing
density and ωLH are studied. It has beenshown that the stair-like frequency chirpingwith the riser Ωi appears near ωLH.
Test ions do not feel 2D fluctuations.

• The simulation results agree with the LHD
experimental results.

50/196NBI heating analysis of LHD deuterium experiments
NBI analysis of time-dependent, multi-ion-species plasma[Yamaguchi+(NF2016)]
before C. pellet injection

Evaluation of neutron emission
rate in NB-blip experiment[Ogawa+(NF2019)]

at C. pellet injection

after C. pellet injection

Power-balance analysis of
H/D plasma of LHD[Takahashi+(NF2018)]• The GNET code has been extended for time-dependent, multi-ionspecies plasma and contributed to isotope effect study.
Ti0=8-10keV• Confinement of fast ions by P-NB was found to be neoclassical bycomparing neutron emission rate by GNET and blip-experiment.
• Benchmark of CONV_FIT3D and TASK/FP using experimental data
and GNET is in progress ( TASK3D-a).
51/196

Summary of research achievements in Integration of MHD andenergetic particle simulations, and the validation• 3D MHD equilibrium, effects of plasma flow on interchange modes,
nonlinear evolution of ballooning modes, and pellet injection with magnetic
islands were studied for LHD plasmas.
• The EP-MHD hybrid code MEGA was extended to simulate kinetic thermal
ions towards the integration of MHD and EP simulations.
• The extended MEGA simulations with kinetic thermal ions demonstrated
that precession drift motion of trapped thermal ions suppress theballooning modes in LHD plasmas.
• Nonlinear evolution of energetic particle driven geodesic acoustic mode andenergy channeling to thermal ions were well reproduced.
• Comprehensive simulations of energetic-particle (EP) driven instabilities
with beam injection and collisions revealed that resonance overlap ofmultiple Alfvén eigenmodes (AEs) accounts for the critical beam power forthe sudden increase in fast-ion transport and the trigger of AE burst.
• Full PIC simulation of high-frequency energetic-ion driven instabilities andtime-dependent plasma heating analysis have been developed.

52/196

Neoclassical andTurbulent Transport
Simulations
53/196

Neoclassical and Turbulent Transport Simulations forconstruction of Numerical Simulation Reactor• Reduced models of turbulent transport based on Gyro-Kinetic (GK)simulations for the integrated transport simulation code TASK3D• A new global transport code TRESS+GKV for simulating time evolution of
tokamak core plasmas.
• Investigation of isotope effect on the confinement of LHD plasmas by the
gyro-kinetic simulation code GKV• V&V Studies on mechanism of impurity hole formation in LHD plasmas byusing both gyro- and drift-kinetic transport simulation codes, GKV and
FORTEC-3D• Extension of the global full-f gyro-kinetic simulation code GT5D forinvestigating turbulent and neoclassical transport in helical plasmas

54/196

Construction of reduced models for turbulent transport
S. Toda, Invited talk: AAPPS-DPP B-I46 (2018)
S. Toda et al., Phys. Plasmas 26, 012510 (2019)
Most Read, download top15, 12/15• The reduced models for the heat diffusivities and the quasilinear flux model for theparticle transport based on the GK simulation for the kinetic electron condition are
obtained for the transport simulation.
• For the representative plasmas where Ion Temperature Gradient (ITG) mode isunstable, the plasmas at t=1.8s, t=1.9s, and t=2.2s for LHD#88343 are chosen.
15

50

(a)

40

(b)

30

40

20

10

30

10

20

-10

0
5

-20

10
0

-30
0

5

10

15

00

10

20

30

40

50

-40
-40 -30 -20 -10 0

10 20 30 40■: t=1.8s、1.9s, Rax=3.6m (#88343 LHD)●: t=2.2s, Rax=3.75m (#88343 LHD)

55/196

Transport simulation by use of gyrokinetictransport model
S. Toda et al., Plasma and Fusion Research 14, 340306 (2019)• Transport analysis by the integrated code, TASK3D, by use of heatdiffusivity models based on the GK simulation results for the kinetic electron
condition

56/196

Co-Development(NIFS-QST) of a new coupled global
gyrokinetic transport code: TRESS+GKV• Based on collaborations with QST, a new global transport code TRESS+GKV
is developed, and the both (multiple) ions and electron transport simulation
framework is established.
• TRESS+GKV is for tokamak application at the moment, but is being extended
to 3D system including the direct coupling with the MHD equilibrium solver.
Ion & electron global
simulation by TRESS+GKV

r/a
Nakata IAEA-TM2017(invited), APTWG2017, Plasma2017
Honda JSPS2018, CPC2018

57/196

Isotope effects on turbulent transport and zonal flows:
Cooperative studies with GKV & LHD experiments• Nonlinear GKV simulations for LHD isotope plasmas reveals a significant
isotope mass impacts on turbulence and zonal flows.
• Experimental trend of improved confinement is reproduced for LHD Dplasmas.
GKV simulation for ITG and TEM

GKV simulation for LHD Exp.

Nakata PPCF2016, PRL2017, PPCF2019
Nakata ISHW2017(invited), EPS2018 (invited),
K. Nagaoka FEC2018(oral) K. Tanaka EPS2019(invited)
Nakata JSPF research award(2017), NINS young researcher award(2018)58/196

Gyrokinetic and drift-kinetic simulations for LHD
impurity hole plasma• Comprehensive analyses for anomalous and neoclassical transport of multiion-species plasmas in helical systems are performed by local gyrokinetic
and drift-kinetic simulations.
Neoclassical particle
fluxes vs. Er

Turbulent particle fluxes• GC(trb) remains inward directed within wide ranges of the gradients.
• GC(neo) can be outward with electron-root Er if there exists sufficient directcontributions of injected beam.

59/196

Plasma profile sensitivities in turbulent transport ofhelical plasmas

skip• Ion temperature gradient (ITG) turbulent transports are evaluated by
gyrokinetic simulations using GKV code.
• For wide range of temperature gradients, the heat transport fluxes are
estimated to perform flux-matching (FM) method.
R0=3.75m
R0=3.60m

w/ kinetic electrons
w/ adiabatic electrons

7

20.0

R0 / L Ti

0. 5
ρ=

.46

10

ρ =0

.65

ρ =0

χi/ χi

GB

20

0
0

10

0
ρ=

R0 / LTi

%
-20

10.0

.83

20

0%
+2

30

0.4

0.6

ρ

0.8

1.0

• In NC optimized case, the profile stiffness in turbulent transport is relaxed.
• Based on the profile sensitivities, we succeed to predict the temperature
gradient by FM method against experimental error bars of the gradients which
are obtained by AIC (Akaike’s information criterion).
60/196

Global neoclassical transport simulation codes for
multi-species plasma is being developed• FORTEC-3D code, which solves the 5D drift kinetic equation by 2-weight
scheme, treats the non-local neoclassical transport phenomenon including
the magnetic drift motion both in normal and tangential to the flux surfaces.

Local w/o magnetic drift

Local w/ magnetic drift

GlobalDifference in the potential variation Φ on a flux surface
in LHD plasma according to the drift-kinetic models.

World’s first trial of impurity NCT simulationin 3D configuration + global model

Neoclassical flux in a 3-species LHD plasma. Comparisons of
FORTEC-3D (lines) with a local approximation code (points).

• FORTEC-3D is extended to multi-ions species plasmas, including the effectof potential variation on flux surface to study the impurity transport.
• Radially-local model (LOF3D) has been developed to clarify the effect of
local approximation used in conventional neoclassical transport codes.

61/196

Global full-f kinetic simulation code, GT5D, has been
extended to 3D heliotron/stellarator equilibria• A global full-f gyrokinetic simulation code, GT5D, is extended to general 3D
equilibria provided by VMEC with the aid of the new coordinate transformation
under a collaborative research with JAEA.
• This work has been published by Physics of Plasmas as an Editor’s pick, andalso presented as an invited talk at 2nd Asia-Pacific Conference on Plasma
Physcs.

Er [kV/m]

-1

0.3

r=0.8

0.2

r=0.5

r

r

Er, k (¥)/Er, k (0)0Theory
GT5D

0.4

0.1

-2
-3
-4

r=0.2

0

-5
0

0.1

0.2

0.3
krrti

0.4

0.5

0.6

GT5D
FORTEC-3D
0.2

0.3

0.4

0.5

0.6

0.7

r

• Residual level of the collisionless zonal flow damping shows a reasonableagreement with a theoretical prediction for outer radius (ρ=0.8).
• Neoclassical transport of another global neoclassical code (FORTEC-3D)
has been recovered successfully.

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Summary of research achievements inneoclassical and turbulent transport simulations• The reduced models for particle and heat transport based on the gyrokinetic
simulation for the kinetic electron condition are obtained for the integrated
simulations by TASK3D.
• Based on collaborations with QST, a new global transport code TRESS+GKV isdeveloped, and the both (multiple) ions and electron transport simulation
framework is established.
• Nonlinear GKV simulations for LHD isotope plasmas reveals a significant isotope
mass impacts on turbulence and zonal flows. Experimental trend of improved
confinement is reproduced for LHD D-plasmas.
• The radial particle flux of carbon impurity caused by turbulence remains inward
directed within wide ranges of the gradients. On the other hand, the neoclassicalparticle flux of the impurity can be outward with electron-root Er if there exists
sufficient direct contributions of injected beam.
• A global full-f gyrokinetic simulation code, GT5D, is extended to general 3D
equilibria provided by VMEC with the aid of the new coordinate transformation
under a collaborative research with JAEA.

63/196

Peripheral plasmas& PWI

64/196

Simulations of peripheral plasmas and plasma-wall interaction for
construction of Numerical Simulation Reactor• Impurity transport simulation by 3D transport code EMC3-EIRENE• 2-D electrostatic Particle-In-Cell code PICS2 for Plasma-Wall-Interaction• Integration of Neutral-Transport Code, EMC3-EIRENE and MD Simulation
to calculate molecular hydrogen in LHD plasmas.
• BCA-MD-KMC multi-hybrid simulation for formation of “Fuzz” under
helium plasma irradiation• Finite-Distance Time-Domain (FDTD) simulation on optical properties ofTungsten fuzz structure

65/196

Difference of transport characteristics of Ne and N
has been revealed by modeling and experiment• Impurity transport in the impurity-seeded plasma is simulated by 3D transport
code EMC3-EIRENE.
• Recycling coefficients of neon and nitrogen is modeled as 100% and 0%,
respectively, according to their chemical activity on the divertor plates.
neon

nitrogen• Neon and nitrogen distributions in the plasma obtained by EMC3-EIRENE
are toroidally symmetry and asymmetry, respectively.
• Toroidal distribution of particle flux is symmetry with neon seeding.
• On the other hand, the distribution is asymmetry with nitrogen seeding.
• The modeling reproduced the distributions obtained by Langmuir probes.

66/196

2-D electrostatic Particle-In-Cell code PICS2 has beendeveloped for Plasma-Wall-Interaction researches• A Particle-In-Cell (PIC) code has been developed and applied to thesimulation of a plasma-exposure experiment of NAGDIS-II (Nagoya Univ.)• The code is designed for modeling of magnetized sheath plasma with
arbitrary surface shapes defined by multiple line segments.
• The code has high portability and available for collaborations.
plasm injectionwall
surface• Two types of surface geometries were simulated: (a) step and (b) roof.
• Wide range of flux variation was obtained with the roof type, and that is
consistent with experimental results.
[G. Kawamura et al., Nucl. Mater. Energy 12 (2017) 297]

67/196

Rovibrational Population Calculationof Molecular Hydrogen in LHD Plasmas:
Neutral-Transport Code, EMC3-EIRENE and MD Simulation.
Collaborate with Shinshu Univ., Yamagata Univ., Kyoto Univ.

• H2 density distribution are calculated using Neutral-Transport code with H and H2
data released from Divertor plate, which are simulated by MD-sim.

K. Sawada et al., 17th International Workshop on Plasma Edge Theory in Fusion Devices, 19-21 August, 2019, UCSD.

• Code integration of neutral transport code, charged particle code (EMC3EIRENE) and the recycling model (MD) is successfully performed.
• H and H2 density profile in LHD can be calculated using integrated code.

68/196

Formation of “Fuzz” under helium plasma irradiation isrepresented by BCA-MD-KMC multi-hybrid simulation• BCA-MD-KMC multi-hybrid simulation solves• helium injection by using BCA (binary collision approx.)• helium diffusion by using KMC (kinetic Monte-Carlo)• tungsten deformation by using MD (molecular dynamics)
+5 nm
0 nm
-10 nm-15 nm

20 nm

He bubble in material

EI=100eV, 1100K, Flux 1.4x1022m-2s-1, Fluence 2.36x1023 m-2 (16.9s in time)• The simulation achieved 100 sec. in elapse time for 40 day in calculation time.
• Helium bubble bursting generates surface roughness. After that, the sputteringand re-deposition of W atoms enhanced the growth tungsten fuzzy nanostructure.
69/196

Finite-Distance Time-Domain Simulation
skip
on Optical Properties of Tungsten Fuzz Structure
Collaborate with Nagoya Univ., Kushsu Univ., Kyushu Inist. Tech., NIFS

• 3D structure data of fuzz tungsten are obtained by electron tomography usingtransmission electron microscopy (TEM/ECT).
• Reflectance of fuzz can be calculated by FDTD simulation.

H.Nakamura et al., ISPlasma2018/IC-PLANTS2018, Meijo University, Nagoya, Japan. March 4-8, 2018

• We clarify a mechanism of the electromagnetic (EM) field absorption in the
nano-structured tungsten quantitatively by the FDTD simulation.
• The nano-structures enhance the EM-field around them, and theenhanced EM-field generates the induced current in the tungsten surface.

70/196

Summary of research achievements in simulations ofperipheral plasmas and plasma-wall interaction• Difference of transport characteristics of Ne and N is revealed bymodeling and experiment.
• 2-D electrostatic Particle-In-Cell code PICS2 is developed for Plasma-WallInteraction researches.
• Neutral-Transport Code, EMC3-EIRENE and MD Simulation are integrated
to calculate molecular hydrogen in LHD plasmas.
• Formation of “Fuzz” under helium plasma irradiation is represented by
BCA-MD-KMC multi-hybrid simulation.
• A mechanism of the electromagnetic field absorption in the nanostructured tungsten is quantitatively clarified by the FDTD simulation.

71/196Integrated code

72/196

Integrated Code and Collaboration with
Fusion Engineering Research Project• Progress in TASK3D-a and TASK3D-p• Applications of TASK3D-a to LHD deuterium experiment• Implementation of Data Assimilation approach to TASK3D• Application of TASK3D, FORTEC-3D, EMC3-EIRENE, and VR
to helical reactor design studies

73/196

Extension of Integrated Transport Analysis Suite,TASK3D-a, for LHD Experiment Analyses• Substantial progress made to be compatible with LHD deuterium experiment (a03
and a04, such as NBI module extension to include He and D).
• Loose coupling with large-scale simulation codes (such as DKES/PENTA).

74/196

Applications of TASK3D-a to LHD deuterium experiment (1)K. Tanaka+, accepted for publication in NF (2019).
H. Yamada+, 27th IAEA FEC, EX/P3-5 (2018).
Accepted for publication in Phys. Rev. Lett. (2019).

K. Nagaoka+, accepted for publication in NF (2019).

M. Kobayashi+, accepted for publication in NF (2019).

• Transport analyses database has been accumulated for studying isotope effect• Contributions to many LHD experiment papers

75/196

Applications of TASK3D-a to LHD deuterium experiment (2)Development of (easy-to-use) neutron
emission calculation tool (daily usedfor LHD experiment planning) based on
TASK3D-a

Benchmark of codes for neutron emission
calculation (CONV_FIT3D, FBURN,TASK/FP) based on TASK3D-a
H. Nuga+, PFR 14 (2019) 3402075.

R.Seki+., PFR 14 (2019) 3402126.

Time [s]FBURN：K. Ogawa+, PPCF 60 (2018) 095010.76/196

Progress made in predictive version, TASK3D(-p)
Ranging comparison and validation
can be possible (towards acquiring “relevant” model)
Extension of transport models (χ)•

Gyro-Bohm, Gyro-Bohm x ∇T•

Zeff, Aeff model• Neural-Network based(S. Maeta, (Kyoto U., D3), submitted to J. Fusion Energy (2019).)• Statistical induction (M. Yokoyama, Nucl. Fusion 59 (2019) 094004.)

77/196

Implementation of Data Assimilation approach (TASK3D)• Data assimilation: Optimizing a numerical model with observations (by replacing
variables, constants and initial values of the model with probability distributions(state space model)• Successfully employed in weather/oceanic area ⇒ implementation to TASK3D
for fusion research (collaboration established among Kyoto U., The Institute of
Statistical Mathematics (ISM) and NIFS)
Courtesy of Y. Morishita(Kyoto U., M2)

skip

LHD
data
78/196

Implementation of Data Assimilation approach (TASK3D)
LHD plasma
114053)case was successfully executed (time window of•• NBI-heated
Implementation
done,(shot:
an example• Cycleofdata
assimilation:
40ms~ 2 s performed), and then the relevant paper was submitted.
• Ensemble member: 2000• Physics interpretation of “optimized model”, application to other discharges etc., areforeseen.

#114053_Ti
reff/a99
0.0
0.4
0.7

#114053_Te

Courtesy of Y. Morishita(Kyoto U., M2)
0.2

reff/a99
0.0
0.4
0.7

Time [s]1.8
79/196

Collaborations with Fusion Engineering Research Project(FERP) have been deepening and expanding (1)• In the collaboration with FERP, TASK3D-a and other kinetic codes (FORTEC-3Detc.) are utilized for feasibility study of helical reactor design FFHR-d1 and -c1.
Impact of bootstrap current
on equilibrium in FFHR-d1

Feasibility study of FFHR-c1

FFHR-d1~ , ~ .

DKES/PENTA
T.Goto et al., NF 57 (2017) 066011.

T.Goto et al., IAEA-FEC 2018 FIP/P7-39.
T. Goto et al., NF 59 (2019) 076030.

• Q~10 steady-state operation scenario of FFHR-d1 was sought by 1D transport
analysis tools. In particular, the impact of bootstrap current on MHD equilibrium
was evaluated by iterating MHD and neoclassical calculations.

~11 m) reactor FFHR-c1 was carried out using• Feasible study of compact (TASK3D-a modules, which turns out to predict Q=10~15 operation point.

80/196

Collaborations with Fusion Engineering Research Project(FERP) have been deepening and expanding (2)Impact of a liquid divertor,
REVOLVER-D, on impurity behaviour

VR visualization of reactor design CAD data
The viewer is watching the movement ofrobot arm which grasps the component.

G. Kawamura et al., PFR 13 (2018) 3403034.

• Influence of a limiter (resembling REVOLVER-D)
was evaluated by using EMC3-EIRENE code.

• The CAD design data of future reactor
was visualized in VR system.

• Decrease of core Te is caused by the limiter
placed deeply in the plasma.

• Component interference, installation anddetachment of components, andmovements of robot arm etc. can bechecked from any viewpoints.

• Impurity with higher atomic number has stronger
impact on the plasma. Sn data is not available,
but its influence is thought to be larger than Ge.

81/196

Summary of research achievement:
Integrated Code and Collaboration with
Fusion Engineering Research Project• TASK3D-a is extended by coupling to DKES/PENTA and NBI
module for analyses of LHD deuterium experiment.
• TASK3D-p is extended by incorporating new transportmodels.
• Data Assimilation approach is successfully implemented
to TASK3D.
• TASK3D and FORTEC-3D are utilized for design study of
FFHR.
• EMC3-EIRENE code and VR sytem support fusion
engineering studies.
82/196

[2]-(2)83/196

2. Research achievements

Does the NSRP produce high-level achievements in accordance withinternational standards for the following research areas described in the third
midterm goal and plan by promoting theory and computer simulation researchutilizing the Plasma Simulator?
(2) Academic systematization of fusion science and related science andengineering

NSRP has produced high-level achievements in theory and computer
simulation research contributing to academic systematization of fusion
science and related science and engineering in the following areas:• PIC simulations of magnetic reconnection, magnetic sonic waves,impurity ion transport, and ICF plasma.
• Studies of two-fluid tearing instability, interchange/tearing
instabilities, and Hall MHD turbulence.
• Advanced visualization technology• Systematization through publishing a textbook and review papers
84/196

Research achievements in particle simulations• Development of electromagnetic particle simulation code, PASMO• Magnetic reconnection• Magnetic sonic waves• Impurity ion transport• ICF plasma.

85/196Development of PASMO

skip• The PASMO code is a electromagnetic (EM) particle simulation code.
• 2DPASMO is 2D3V EM PIC code. It focuses survey on the physics such as
acceleration and heating in a reconnection plane.
• 3DPASMO is three-dimensional (3D) EM PIC code. It can analyze 3Ddynamics in the reconnection.
3DPASMO
2DPASMO• Dynamical load balance library “OhHelp” is implemented to 3DPASMO.
• Optimization for thread parallelization is applied to 3DPASMO.
• Domain decomposition with MPI is also implemented to 2DPASMO.
• These optimization will increase simulation size of reconnection.
86/196

The electromagnetic particle simulation code PASMO
was optimized for thread and distributed parallelization• The random memory access takes place during the gather and pusher
processes.
• If the simulation domain is decomposed uniformly, a load balance problem
may appear when the number density of particles are not uniform.
• The PASMO code was optimized from the viewpoints of a distributed
memory and multi-processor computer system.

skip• We exchanged the particle data array, implemented the bucket sorting andthe sort process of particles in the particle data array, inserted the directive“schedule(dynamic)”, and changed loop structure, in order to access thememory continuously. As a result, the elapsed time decreased by 53.9%
compared to the original code.
• In order to solve the load imbalance, we implemented the OhHelp library,which had the dynamic load-balancing algorithm by making eachcomputation node help another heavily loaded node, to the PASMO code.
As a result, the elapsed time decreased compared to the original code insome simulation conditions.
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3D parallelized Poisson solver library “PoissonFFT2”
has been developed and will be provided for PS users• PoissonFFT2 has been developed by NIFS and Fujitsu and is adaptable tothe 3D/2D domain decomposition, that is, 3D/2D distributed data.
• In PoissonFFT2, the parallelized multi-dimensional fast Fourier transform(FFT) libraries FFTW, P3DFFT, and 2Decomp&FFT are used.

skip• PoissonFFT2 transforms 3D distributed data into 2D/1D distributed data
because the FFT libraries are not adaptable to 3D distributed data.
• PoissonFFT2 can solve both the differential equation form and thedifference equation form of Poisson equation and can apply the smoothing
function and periodic, Dirichlet, and Neumann boundary conditions.
• PoissonFFT2 has been installed into PASMO, up3bd, and extended-MHD
codes, will be opened within a few years, and will be provided for Plasma
Simulator users who need a parallelized Poisson solver library.

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PASMO simulations have revealed the mechanism of
ion effective heating during magnetic reconnection.
• During driven magnetic reconnection, a ring-shaped or an arc-shaped
velocity distributions of ions are formed in the downstream. This means thations are effectively heated.

• The ion heating energy (density x temperature) is proportional to the squareof the reconnection (poloidal) magnetic field, while the ion temperature islower as the guide (toroidal) magnetic field.
• The two tendencies are in good agreement with experimental results in STs
89/196

Parallel electric field in nonlinear magnetosonic wave inthree-component plasmas has been theoretically analyzed• The particle simulations showed that the electric field parallel to the magnetic field
in a magnetosonic shock wave plays crucial roles in particle acceleration mechanismsthat can be applied to production of energetic particles in space and astrophysicalplasmas.
• In this study, the parallel electric field E|| and its integral F along the magnetic fieldin nonlinear magnetosonic wave in three component plasmas (two-ion-species
plasma and electron-positron-ion plasma) have been theoretically analyzed withattention to the frequency range.

skip

The maximum values of F have been derived as
two-ion-species plasma

electron-ion-positron plasma: wave amplitude: densities of electron, ion, and positron

These are much greater than FM for the frequency range
.
Test
ions
do
not
feel
2D
fluctuations.
The theory can explain the strong particle acceleration shown by the simulations.
90/196

Particle simulation codes for study of kinetic dynamics
in boundary layer plasmas have been developed• 3D electrostatic PIC codes for study of filament dynamics (p3bd / up3bd
codes) have been improved and developed.
• 1D electrostatic PIC-MCC code for study of detachment dynamics(PAMCADE) has been developed.

skip• The procedure of setting “hole” structure has been installed into p3bd code.
• up3bd code has been developed with the domain decomposition in thebasis of p3bd code.
• In up3bd code, PoissonFFT2 library and in-place bucket sort are applied.
• up3bd code shows better scalability and performance than p3bd code.

91/196

3D effect of particle motion on plasma filament
dynamics has been revealed with the PIC simulation• This study has demonstrated kinetic behaviors on the plasma filament
propagation with the p3bd code.
• It is shown for the first time with the p3bd code that the plasma particle
motion influences plasma filament dynamics three-dimensionally.

skip• The poloidal symmetry breaking in the filament propagation occurs in thehigh Ti case and significantly depends on the toroidal position.
• The large pre-sheath drop on the hill side induces the strong dependence ofthe perpendicular electric field in the filament on the toroidal position.
• Such a 3D structure of the electric field influences the filament dynamics.

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Impurity ion transport by plasma filaments has been
investigated with the PIC simulation• It is shown for the first time with the p3bd code that the plasma filaments
transport impurity ions.
• This study might be able to explain the difference of impurity transport
property between tokamak and helical devices.

• The blob penetrates to the impurity ion region and sweeps impurity ions.
• The impurity ions which surround the blob are transferred in the grad-B
direction.
• The hole moves from the impurity ion region and carries impurity ions in thegrad-B direction.
93/196

Dependence of the impurity ion transport by a plasma
filament on various parameters has been investigated• The dependence of the impurity ion transport by a plasma filament onvarious parameters has been studied with the p3bd code.

skip• This study suggests that the statistics regarding the size of filaments
generated in devices are important for estimating the effect of filaments on
the total impurity ion transport and that the impurity ion transport by filaments
is not negligible in the high ion temperature plasma.

• The effective diffusivity of impurity ions
1) has a positive correlation with the filament poloidal size,2) has a slight inverse correlation with the ion temperature, and
3) becomes quite small in the heavy impurity ion mass case.

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Isotope influences on the filament dynamics havebeen investigated with the PIC simulation skip
• The ion inertial influences, i.e., the isotope influences, on the sheath-limited
filament dynamics have been investigated with the p3bd.
• In this study, the isotope influences in the polarization drift effect and thesheath effect are evaluated.

• The sheath effect expected by the conventional static estimation for asheath-limited filament is cancelled out by the polarization drift effect indeuterium-tritium (D-T) plasmas.
• The radial propagation speed of a filament becomes slightly slower in D-T
plasma than in light hydrogen (H) plasma because of the gyro motion effect.
95/196

As a preliminary work, an energy boost of the heating
laser has been modeled in ion assisted fast ignition• The ion assisted fast ignition scheme is suggested, where low-density CH
foam is introduced as a ion beam generator, and additional core heating by
proton (H+) and carbon (C6+) beams is expected.
• Integrated simulations, in which particle data in 2D PIC fiscof2 code aretransferred into the source term in 2D core heating fibmet2 code, are carriedout to evaluate the core heating properties.

• The density averaged electron temperatures increase more than extension
factors of the total energy, but energy relaxation is not enough.
• Electrons near the injection point are heated more than 5 keV, but coreelectrons are not heated so much.

96/196

Research achievements in studies of
two-fluid tearing instability
interchange/tearing instabilities
and Hall MHD turbulence.

97/196Growth rate and eigenfunctions for two-fluid tearing
instability become complex in cylindrical geometry• The two-fluid resistive tearing mode instability in a periodic plasma cylinderof finite aspect ratio is investigated numerically.
• Research collaboration with MIT• The real and imaginary parts of the growth rate and the eigenfunctions
become comparable when parameters such that the cylindrical aspect ratio
and two-fluid effects are of order unity.
98/196

Ｉnterchange/tearing instabilities in 2D slab with anumerical model for edge plasma• Numerical simulations of interchange/tearing instabilities in a 2D slab with anumerical model foredge plasma resistivity are carried out by the use of
MUTSU/MINOS code. (Collaborative work with IFS UT Austin by JIFT program.

Figure 1• A numerical model with current diffusivity is developed to enforce a low level
saturated current profile in the SOL region as well as a current jump acrossthe LCFS.
• The numerical simulations (b) show that interchange modes can transform
into tearing modes, as the current-interchange tearing modes (a) which has
been proposed by Zheng and Furukawa (2010).

99/196The modulational parity instability is one of themechanisms of parity mixture in interchange modes.
[ M. Sato and A. Ishizawa, Phys. Plasmas (2017) ]• Nonlinear formation of magnetic islands in resistive interchange modes has
been investigated by two-fluid reduced MHD simulations.

skip

t=40000

n=0 (interchange parity)

t=83500

n=1(interchange parity)n=1(tearing parity)• A saturated state of the interchange mode is unstable against the tearing parity
mode. This instability is called as the modulational parity instability where thepump mode is the interchange mode, and the side-band mode corresponds to100/196
the tearing parity mode representing the magnetic island formation.

3D Extended MHD Large Eddy Simulations ofBallooning Instability in LHD• Large Eddy Simulation (LES) approach has been introduced to solve
extended MHD (XMHD) equations numerically for studying nonlinear
evolution of ballooning instability in LHD.
• Our LES (by the use of MUTSU/MINOS code) successfully reproduce basic
nature of ballooning instability in LHD and show importance of sub-grid-scaleeffects in numerical simulations.

Figure 1• (a) Diamagnetic flow is induced in LES of XMHD of Rax=3.6m inward-shifted
LHD plasma (b0=3.6%) and move on to nonlinearly saturated state.
• (b) By a parameter study for SGS model of LES, we can see that plasmacore can be stable for a stronger SGS effect.

Development of MUTSU-T3 code

101/196skip• A new pseudo-spectral simulation code, MUTSU-T3 code, has beendeveloped for a study based on an extended MHD model.
• The new simulation code makes use of P3DFFT, FT3D, and FFTE 3d Fast
Fourier Transform codes as well as VISMO in-situ visualization library.
Figure 1

Figure 2• The new code has been used for a study of homogeneous and isotropic
turbulence of Hall MHD (Fig.1) and extended MHD models (Fig.2).
• Numerical simulations together with VISMO library shows effectiveness of
in-situ visualization.

102/196Development of SGS model for LES of XMHD based on
DNS of Hall MHD turbulence
skip• SGS model required for LES of extended MHD (XMHD) has been developed
based on DNS of Hall MHD turbulence.
• LES with our SGS model, by the use of MUTSU-T3/XMHD3D successfully
reproduce turbulent energy spectra of Hall MHD turbulence.

• SGS model contains effects of flow shear and current density in the gridscale.
• Kinetic and magnetic energy spectra, EK(k) and EM(k), of DNS by N3=10243
is well reproduced by LES of N3=1283.
103/196

Research achievements in VR visualization

104/196

The CAD data of future fusion reactor was visualized in
VR space.

skip• It is important to design a reactor while considering previously how toassemble the components, because it will be possible to build up the reactor
efficiently. The fusion reactor is designed to replace the components
periodically in the fusion operation, and it is necessary to give consideration
to the replacement process in advance.

• CompleXcope visualized the CAD data of future fusion reactor.
• The viewer can come into the reactor and confirm the design. It is possible towatch the movement of the components as animated graphics in the VR
space. The viewer can also grasp the component by his virtual hand in the
VR space.

105/196

In-situ visualization library “VISMO” is developed.
• In-situ visualization library VISMO is developed to couple the simulation codewith the visualization code, and to perform visualization process together
with simulation on the same supercomputer. The VISMO has also a function
which generates point-cloud data for interactive visualization.
• This study is based on the collaboration framework between NIFS andHyogo University.

• The new function was implemented to VISMO. The particles are visualizedwith color which can shows the physical valuable, for example, the particle
velocity. The radius of particle can also be changed.
• The point cloud data is visualized by CompleXcope.
106/196

The visualization contents developed by “Unity”

skip• Many kinds of visualization devices are introduced in the world, that is, head
mount display, smartphone, CAVE, and so on.
• It become difficult to develop the visualization application in accordance withthe visualization devices.
• We implemented a game development engine “Unity”.

• The CAD data of the periphery devices of LHD can be easily installed to the
VR visualization content “LHD vessel”.
• The VR visualization content “LHD vessel” can be easily implemented to thehead mounted display system.
• This study is based on the collaboration framework between NIFS andHyogo University and JAMSTEC.

107/196

The application of Visualization technology to the otherresearch field.

skip• The unique chaotic structure was found in uniform and anisotropic universe
model by solving the Einstein equation.
• In usual analysis in chaos structure, the Poincare map is used.

• In order to analyze the whole structure of the chaos, we visualized the orbit
data in three dimensional space.
• It was found that each orbit rotated spirally.
• This study is based on the collaboration framework between NIFS. Osaka
Prefecture University and Texas University at Austin.
108/196

Systematization through publishinga textbook and review papers

109/196

NSRP contributes to contributes to theoreticalsystemization of fusion plasma physics throughpublishing a textbook on plasma simulation (in Japanese)「プラズマシミュレーション 多階層複雑現象の解明へ」• Basic principles of plasma physics andnumerical simulation are explainedtargeting undergraduate, graduate
students, and researchers as readers.
• Recent results from state-of-the-art
simulations of fusion and space plasmas
are illustrated.
• 7 of 15 authors are from NIFS.
• Published from Kyoto Univ Press
in Dec. 2018
• A5 format, 7 chapters, 400 pages
110/196

NSRP contributes to theoretical systemization of fusion
plasma physics through publishing many review papers
Project review:“Numerical Simulation Reactor Research Project at the National Institute for Fusion Science”
1. Introduction•

R. Horiuchi, J. Plasma Fusion Res. Vol. 92, 785 (2016) [in Japanese]

2. Simulation Researches in Fusion Plasmas• K. Ichiguchi et al., “2.1 MHD Equilibrium and Stability,” J. Plasma Fusion Res. Vol.
92, 787 (2016) [in Japanese]• R. Kanno et al., “2.2 Transport Simulation of Core Plasmas,” J. Plasma Fusion
Res. Vol. 92, 794 (2016) [in Japanese]• Y. Todo et al., “2.3 Physics of Energetic Particles, Waves and Heating,” J. Plasma
Fusion Res. Vol. 92, 806 (2016) [in Japanese]• K. Suzuki et al., “2.4 Peripheral Plasma Transport and Plasma-Wall Interaction,” J.
Plasma Fusion Res. Vol. 92, 810 (2016) [in Japanese]• M. Yokoyama, “2.5 Development of the Integrated Transport Analysis Code,” J.
Plasma Fusion Res. Vol. 92, 814 (2016) [in Japanese]
3. Sophistication of Computational Science and Fundamental Physics Simulations• S. Ishiguro et al., J. Plasma Fusion Res. Vol. 92, 821 (2016) [in Japanese]

111/196

NSRP contributes to theoretical systemization of fusion
plasma physics through publishing many review papers
H. Sugama,“Modern gyrokinetic formulation of collisional andturbulent transport in toroidally rotating plasmas,”
Rev. Mod. Plasma Phys. 1:9 (2017)[downloaded 1,500 times, as of Nov. 2019]
Y. Todo,“Introduction to the interaction between energetic
particles and Alfven eigenmodes in toroidal plasmas,”
Rev. Mod. Plasma Phys. 3:1 (2019)[downloaded 1,600 times, as of Nov. 2019]
H. Sugama,“Momentum Transport, Electric Field Formation, and Symmetry under Parity Transformationin Torus Plasmas,”
J. Plasma Fusion Res. 92, 539 (2016) [in Japanese]
H. Sugama and the Numerical Simulation Reactor Research Project Group,“Recent Progress in the Numerical Simulation Reactor Research Project,”
Plasma Fusion Res. 14, 3503059 (2019) [Overview Article]

112/196

NSRP contributes to theoretical systemization of fusion
plasma physics through publishing many review papers“Simulation of Magnetically Confined Fusion Plasma by Integrated Code and Its Prospect”
J. Plasma Fusion Res. 95, 423 (2019) [in Japanese]
1. “Development of Integrated Code for Fusion Plasma Simulation,”
NIFS staff
N. Hayashi, A. Fukuyama, S. Murakami, M. Yokoyama, T. Fujita
2. “Physics Modules Constituting Integrated Code,”
S. Murakami, M. Honda, N. Aiba, A. Matsuyama, N. Hayashi, K. Hoshino,
T. Fujita, A. Fukuyama, M. Yokoyama
3. “Status of Integrated Code Development in Japan and Overseas,”
A. Fukuyama, N. Hayashi, S. Murakami, M. Yokoyama, T. Fujita
4. “Application of Integrated Code: Experiment Analysis, Physics Understanding
and Development of Operation Scenario,”
M. Yokoyama, S. Satake, M. Honda, N. Aiba, N. Hayashi, M. Yagi,
T. Fujita, S. Murakami, R. Seki, H. Yamaguchi, H. Nuga
5. “Future Prospects of Integrated Code Development,”
M. Honda, E. Narita, N. Hayashi, M. Yagi, A. Fukuyama, S. Murakami,
M. Yokoyama, T. Fujita
6. “Conclusion and Acknowledgements,”
N. Hayashi, A. Fukuyama, S. Murakami, M. Yokoyama, T. Fujita, M. Honda
113/196

Advanced formulation of drift and gyro-kinetic equations
for collisional and turbulent transport simulationsskip• A novel radially local drift kinetic equation that includes both ExB and tangential
magnetic drift terms is derived. It is written in the conservative form and has
favorable properties for numerical simulation that any additional terms for particle
and energy sources are unnecessary for obtaining stationary solutions [H. Sugama,
S. Matsuoka, S. Satake, and R. Kanno, Phys. Plasmas 23, 042502 (2016)].

• A novel gyrokinetic formulation is presented by including collisional effects into the
Lagrangian variational principle to yield the governing equations for background andturbulent electromagnetic fields and gyrocenter distribution functions, which cansimultaneously describe classical, neoclassical, and turbulent transport processes
in toroidal plasmas with large toroidal flows. The particle, energy, and toroidal
momentum balance equations are given in the conservative forms, which aredesirable properties for long-time global transport simulation [H. Sugama, M.
Nunami, M. Nakata, and T.-H. Watanabe, Phys. Plasmas 24, 020701 (2017)].
• The Eulerian variational principle for kinetic plasma equations in a generalcoordinate system is presented. The invariance of the action integral under anarbitrary spatial coordinate transformation is used to obtain the momentum
conservation law and the symmetric pressure tensor in a more direct way thanusing conventional methods [H. Sugama, M. Nunami, S. Satake, T.-H. Watanabe,
Phys. Plasmas 25, 102506 (2018)].

114/196

Improved linearized model collision operator for thehighly collisional regime is presented

skip• The improved model is constructed so as to give exactly the same friction-flow
relations as those derived from the linearized Landau operator, and accordingly it
can be used to accurately evaluate neoclassical transport fluxes in all collisional
regimes.
• In addition, the improved collision operator for gyrokinetic equations is derived bytaking the gyrophase average with the finite gyroradius effect taken into account.
• The improved model operator is useful for kinetic simiulation to investigatetransport processes of impurity ions such as tungsten in future LHD and ITER
plasmas.
Field particle part of the linearized model collision operator

Correction term

H. Sugama et al., Phys. Plasmas 26, 102108 (2019) 115/196[2]-(3)
116/196

2. Research achievements

Does the NSRP produce high-level achievements in accordance withinternational standards for the following research areas described in the third
midterm goal and plan by promoting theory and computer simulation researchutilizing the Plasma Simulator?
(3) Are research achievements steadily made according to the plan of
the NSRP?

NSRP has produced high-level achievements according to the third midterm plan.
• Advance researches for developing and integrating simulation codes- Model core turbulent transport and apply it into integrated transport code
- Incorporate multiple ion species effects into transport codes- Improve MD simulation for PFM• Validate simulation codes by comparison with experimental results• Conduct simulation researches on related basic physics• Promote domestic and international collaborations including ITER
• Improve the performance of the Plasma Simulator during FY2019(maintaining the joint use rate of Plasma Simulator at 100%)
117/196

Research achievements made according to the plan of NSRP (1)

•

•

•

Effectively use Plasma Simulator for construction of the Numerical Simulation Reactor
to advance the researches for the development, the extension, the high precision, andthe integration of the 3D simulation codes→ Extension of global GK codes (GT5D & XGC-S) for helical systems(PoP2018, IAEA2018, ISHW2019, Plasma2019)- Combining kinetic thermal ion simulation with MHD (IAEA2018, NF2019, ISHW2019)- Integration of Neutral-Transport Code, EMC3-EIRENE & MD simulation
for molecular hydrogen in LHD (PET2019).
Model turbulent transport in core plasma and apply the model into the integrated
transport code by the end of FY2019→ ci , ce & quasilinear flux models based on GK simulation (PoP2019)- Application of ci , ce models to TASK3D for LHD (PFR2019)- TRESS+GKV for a tokamak (Plasma Conference 2017)
Incorporate multiple ion species effects into various transport codes→ Multiple ion species incorporated into GKV (PPPCF2017), GNET (NF2016),
TASK3D (NF2017), FORTEC-3D (submitted to CPC)
Develop molecular dynamics simulation techniques and build new models necessaryfor evaluating physical properties of plasma facing materials such as tungsten→ BCA-MD-KMC multi-hybrid simulation of tungsten fuzzy nanostructure (PFR2018)
118/196Research achievements made according to the plan of NSRP (2)• Improve the code accuracy by comparison with the experimental results on
the three-dimensional equilibrium, transport, instability and nonlinear
evolution of magnetically confined plasmas including LHD plasmas→ Validation of MIPS (NF2017), MEGA (NF2016, 2019, PoP2017, PRL2018),
GKV (PPCF2016, 2019, PRL2017, ISHW2017, EPS2018, NF2016, 2019),
FORTEC-3D (PoP2018), EMC3-EIRENE (NME2017), TASK3D (NF2017)
against LHD, JT60U, DIII-D, W7X, Heliotron J, EAST, NAGDIS-II, RELAX, …
Conduct simulation researches on related basic physics→ PIC simulations of magnetic reconnection (PoP2019),
magnetic sonic waves (PFR2018),
impurity ion transport (NF2017, PoP2019), and ICF plasma (JoP:CS2016)- Studies of two-fluid tearing instability (PoP2018),
interchange/tearing instabilities (PoP2017),
LES of Hall MHD turbulence (JCP2016)- Advanced visualization (JSST2018 Outstanding Presentation Award)

119/196

Research achievements made according to the plan of NSRP (3)Promote domestic and international collaborations including ITER
→ See the next chapter [3].
Improve the performance of the Plasma Simulator more than four times
compared to the current system during FY2019→ Plasma Simulator is to be upgraded in June 2020.
From survey of technology trends, one year delay from the originalschedule was decided to achieve the target performance.
• Maintain the joint use rate of Plasma Simulator at 100%.
→ The joint use rate of Plasma Simulator has been maintained at 100%.

120/196

The NSRP has produced many high-level achievementsin accordance with international standards
Selected in Nucl. Fusion Highlights 2016
Y. Todo et al., Nucl. Fusion 56, 112008 (2016)
Fast ion profile stiffness due to the resonanceoverlap of multiple Alfvén eigenmodes

Selected as Editor’s Pick of Phys. Plasmas
S. Matsuoka et al., Phys. Plasmas 25, 022510 (2018)
Neoclassical transport benchmark of global full-f
gyrokinetic simulation in stellarator configurations

Ranked 12th of Top 15 Most Downloaded
Articles in the past year from Phys. Plasmas
S. Toda et al., Phys. Plasmas 26, 012510 (2019)
Modeling of turbulent particle and heat transport inhelical plasmas based on gyrokinetic analysis

Achievements during 2016-2019
Item

Number

Refereed Journal Papers

266

PRL / Nature Comm / Sci Rep

3/2/1

PoP / NF / PPCF

37 / 60 / 24

Invited presentations atinternational conferences
except IAEA-FEC

44

Presentations at
IAEA-FEC 2016 & 2018 (oral)

83 (18)Invited presentations atdomestic conferences

10

Awards to NSRP members
of NIFS10
121/196

Research achievements
disseminated throughEurekAlert (AAAS)

122/196Research achievements
disseminated throughEurekAlert (AAAS)

123/196

Research achievement
disseminated throughnewspapers
Clarifying the mechanism for suppressing
turbulence through ion mas

124/196Research achievements
disseminated throughnewspapers
PIC simulation ofplasma heating bymagnetic reconnection

Application of VR tofusion reactor design
PIC simulation ofcoherent structure in
peripheral plasma

125/196[3]-(1)
126/196

3. Promotion of cooperation and collaborations(1) Is collaboration research with universities based on theory and simulation
research appropriately promoted? Does it contribute to the progress of the
NSRP?
(2) Does the NSRP contribute to enhancing functions of universities andinstitutes as the center of excellence for fusion plasma simulation? Does
the NSRP commit to the promotion of interdisciplinary collaboration andresearch?
(3) Does the NSRP contribute to international cooperation including ITER, BA
activities, and others through international collaboration activities?

NSRP promotes collaboration research by integrating thehigh capabilities of universities and institutes for making
progress of NSRP.
•••

NSRP cooperation program has accepted about 60-70 researchsubjects involving about 180 collaborators each year.
The Plasma Simulator Symposium provides collaborators with
opportunities for the exchange of research information.
Collaborators from universities and institutes join and support the
NSRP task groups to enhance the project research activities.

Framework of the general collaboration
research programs at NIFS relating to NSRP

127/196skip

Three categories in NIFS collaboration programs regarding totheory and numerical simulation
1. Theory collaboration research• Programs proposed by NIFS
• Programs proposed by domestic collaborators
2. Plasma Simulator collaboration research• Programs proposed by NIFS
• Programs proposed by domestic collaborators
3. Collaboration research utilizing the LHD Numerical Analysis
Server128/196

NSRP collaboration program has accepted about
60-70 research subjects involving about 180
collaborators each year
Number of collaboration subjects
NIFS

Out of NIFS

Total number of collaborators

Total

NIFS

Number

50
40
30

56
32
24

51
29
22

60

53
29
24

65
35
30

33
27

68

67
36
31

38
30

140

68

36
32

120

Number70
60

Out of NIFS

160

80

119

134
108

112

149

144
125

105

100
80
60

20

40

10

20

50

50

50

49

2012

2013

2014

2015

50

45

50

54

2016

2017

2018

2019

0

0
2012

2013

2014

2015

2016

2017

2018

2019

Year

Year

• The number of accepted collaboration subjects is approximately 60-70.
• The total number of collaborators in the accepted subjects is approximately
180 each year, including 50 from NIFS and 130 from universities.
129/196

Plasma Simulator Symposium provides collaboratorswith exchange of research information• Plasma Simulator Symposium (Simulation Science Symposium) has been
held for the “Plasma Simulator” users to report recent numerical results, andalso to introduce recent topics in large-scale numerical simulations in various
fields, to the users.
PSS Participants

135

137

133

130

2016

2017

2018

2019
130/196

Many collaborators from universities and institutes join
the NSRP task groups to make progress of NSRP
group

leaderPlasma fluid equilibrium stability
Energetic-particle physics
Integrated transport simulation

member

K. Ichiguchi

13（sim. 7, exp. 3, collab. 3）

Y. Todo

9 （sim. 4, exp. 3, collab. 2）

M. Yokoyama 28（sim. 4, exp. 13, collab. 11）

Neoclassical and turbulent transport
simulaton

R. Kanno16（sim. 8, exp. 3, collab. 5）

Peripheral plasma transport

Y. Suzuki

20（sim. 4, exp. 5, collab. 11）

Plasma-wall interaction

H. Nakamura

18（sim. 4, exp. 3, collab. 11）

Multi-hierarchy physics

H. Miura

18（sim. 12, collab. 6）

Simulation science basis

H. Ohtani

16（sim. 12, exp. 1, collab. 3）

Sim.: simulation staff, exp.:experiment staff, collab.:domestic collaborators••

Many collaborators from other projects and from outside NIFS have joined thesetask groups to enhance collaboration and cooperation studies.
Most of the simulation staff in the NSRP also participate in other task groups.
131/196

Rovibrational Population Calculationof Molecular Hydrogen in LHD Plasmas:
Neutral-Transport Code, EMC3-EIRENE and MD Simulation.
Collaborate with Shinshu Univ., Yamagata Univ., Kyoto Univ.

• H2 density distribution are calculated using Neutral-Transport code with H and H2
data released from Divertor plate, which are simulated by MD-sim.

K. Sawada et al., 17th International Workshop on Plasma Edge Theory in Fusion Devices, 19-21 August, 2019, UCSD.

• Code integration of neutral transport code, charged particle code (EMC3EIRENE) and the recycling model (MD) is successfully performed.
• H and H2 density profile in LHD can be calculated using integrated code.

132/196

Collaborations on EMC3-EIRENE:
1. Tungsten transport and redeposition in LHD
2. Divertor footprint in JT-60SA with RMP field
Collaborate with 1) Keio Univ. 2) Nagoya Univ. , QST. and Keio Univ.

1. Tungsten (W) transport from a W-tile to the neighboring tiles are simulated by
IMPGYRO code with a background plasma obtained by EMC3-EIRENE code.
• Redeposition patterns of W characterized by neutral atoms and ions were
found on different regions.
2. Divertor footprint in JT-60SA with RMP field was obtained for the first time by
EMC3-EIRENE code.
• Splitting of the flux distribution was obtained corresponding to the toroidal mode
number of the RMP field.
Particle flux on theHeat flux on theoutboard divertor

Depositedas neutral

outboard divertor

W-tileDeposited
as ionSplitting133/196

Collaboration with Kyoto University on gyrokinetic
simulation of turbulent transport in helical systems• Drift-wave instability and nonlinear turbulent transport are investigated in two
configurations with different magnetic field structures (LHD and Heliotron J)
by means of electromagnetic gyrokinetic simulations[A. Ishizawa, Y. Kishimoto, T.-H. Watanabe, H. Sugama, K. Tanaka, S.
Satake, S. Kobayashi, K. Nagasaki, and Y. Nakamura, “Multi-machine
analysis of turbulent transport in helical systems via gyrokinetic simulation,”
Nucl. Fusion 57, 066010 (2017)]

ITG turbulence(electrostatic potential)
in Heliotron J plasma• A. Ishizawa, Y. Kishimoto, and H. Sugama,
Parity in Torus Plasmas : 5. Summary and Discussion,
J. Plasma Fusion Res. 92, 564 (2016)

134/196

Numerical diagnostics has been performed to capture
turbulence properties in helical plasmas
Collaborate with Kyushu Univ.

• Combination of simulations for turbulence and experimental measurement
gives synthetic diagnostic of fluctuation patterns in helical plasmas.

LS

0.5
0

r＝
0.65

-0.5
-3.0

-1.0

vertical position [m]• Time series of 3-D turbulence data are obtained by Gyrokinetic code GKV,
and density spectra are extracted from them by utilizing simulation of phase
contrast imaging in the LHD configuration.
measurement configuration
vertical profile of k spectrum comparison of k spectrum
0.8

Exp
S

r＝
0.65

sPCI
0

k ri
1.0
k ri
• A signal integrated along the line of sight of the experimental observation ofphase contrast imaging is calculated.
-4.0 0.0-0.8

0• A vertical profile of the density fluctuation spectrum is reconstructed, andthe spectrum is compared with the experiment.

135/196

Implementation of Data Assimilation approach (TASK3D)• Data assimilation: Optimizing a numerical model with observations (by replacing
variables, constants and initial values of the model with probability distributions(state space model)• Successfully employed in weather/oceanic area ⇒ implementation to TASK3D
for fusion research (collaboration established among Kyoto U., The Institute of
Statistical Mathematics (ISM) and NIFS)
Courtesy of Y. Morishita(Kyoto U., M2)

LHD
data
136/196[3]-(2)137/196

3. Promotion of cooperation and collaborations(2) Does the NSRP contribute to enhancing functions ofuniversities and institutes as the center of excellence for fusion
plasma simulation? Does the NSRP commit to the promotionof interdisciplinary collaboration and research?

••

The NSRP coordinates many collaborations with universities andinstitutes as a COE to enhance their functions for conducting
researches based on fusion plasma simulation.
(Enhancement of functions for education → Chap.[4])The NSRP commits to the promotion of interdisciplinary
collaboration by organizing workshops and symposia under NINS
cooperation programs.
138/196

NSRP organizes several workshops forcollaboration every year.
List of workshops
•

•

•

•

2016
8 Workshops (Non-linear problem and visualization, ,Plasma-wall Interaction, Peripherical plasma, High-beta plasma, Fluid
dynamics, MHD, Visualization)
2017
7 Workshops (Non-linear problem and visualization, ,Plasma-wall Interaction, Peripherical plasma, High-beta plasma, Fluid
dynamics, MHD, Visualization)
2018
9 Workshops (Non-linear problem and visualization, ,Plasma-wall Interaction, Peripherical plasma, High-beta plasma,Numerical simulation, MHD, AI, Visualization)
2019
8 Workshops (Non-linear problem and visualization, ,Plasma-wall Interaction, DNA, Deep learning, Peripherical plasma,High-beta plasma, Data mining, Visualization)

139/196

A) NSRP plays a central role in collaboration with
universities and institutes
Kyoto University:• Electromagnetic gyrokinetic simulation of turbulent transport in helical systems.
• Divertor plasma modeling of Heliotron J
Kushu Inst. Tech., Kyoto Inst. Tech., NIMS, RIKEN, Doshisha Univ., Univ. Toyama., IMS :• Molecular dynamics study on DNA damage by tritium disintegration.
Keio University:• Tungsten transport and redeposition in LHD
Nagoya University, QST, Keio University:• Divertor footprint in JT-60SA with RMP field
Nagoya University, Aichi Inst. Tech.:• Plasma modeling of NAGDIS-II
Tokyo Institute of Technology and Okayama Institute of Technology• Extended MHD (XMHD) simulations of ballooning modes in LHD
Kyoto Institute of Technology:• MIPS simulation reproduced the experimentally-observed helical structure in RFP
University of Hyogo, Kobe University, Konan University, Kyoto University, Nagoya University,
JAMSTEC, National Defense Academy, Osaka Prefecture University:• Visualization of LHD periphery devices, GKV simulation results, magnetic field lines andcosmology simulation of Einstein equation• In-situ visualization
NAOJ:• PIC simulations of relativistic jet launched by black holes
140/196

Collaborations on EMC3-EIRENE:
3. Plasma modeling of NAGDIS-II
4. Divertor plasma modeling of Heliotron J
Collaborate with 3) Nagoya Univ., Aichi Inst. Tech., 4) Kyoto Univ.

3. Plasma modeling of linear device NAGDIS-II was performed for the first time.
• Plasma was modeled in 3D realistic device and target shape, and energy
transport between the plasma and the neutral gas was investigate.
4. Divertor plasma modeling of Heliotron J was performed for the first time.
• Plasm distributions with three different magnetic field configuration wereobtained, and heat flux depositions on the wall were investigated.

141/196

Molecular dynamics study on DNA damage
by tritium disintegration
Collaborate with Kushu Inst. Tech., Kyoto Inst. Tech., NIMS, RIKEN, Doshisha Univ., Univ. Toyama., IMS.

• Using molecular dynamics (MD) simulation, we simulate the structural change of atelomeric DNA by β decay of substituted tritium to helium-3.

H. Nakamura, et al., Jpn J. Appl. Phys., (2019) (accepted).

• From the MD simulation, it is found that as the intensity of the β-decays
becomes larger or as the temperature is increased, the DNA structure
becomes more fragile.
142/196

Collaboration with University of Tokyo & Okayama
Institute of Technology on LES for XMHD turbulence• With an intention to apply for extended MHD (XMHD) simulations ofballooning modes in LHD, SGS model has been developed based on DNS of
Hall MHD turbulence both for isotropic turbulence and for homogeneous,
non-isotropic (magnetized) turbulence.

skip

Figure 1

Figure 2• Our SGS model, which contains effects of flow shear and current density inthe grid scale, and reproduce basic nature of Hall MHD turbulence well bothfor isotropic and magnetized turbulence.
143/196

MIPS simulation reproduced the experimentallyobserved helical structure in RFP
Collaborate with Kyoto Inst. Tech.

• The initial MHD equilibria for the MIPS nonlinear simulation are calculated by
the RELAXFit code with experimental parameters.
• Full toroidal simulations for multiple m=1 modes are carried out for the
resistive time scale.

• External kink eigenmode corresponds to magnetic perturbations observed in
RELAX device.
• Nonlinear restructure of pressure via magnetic reconnection forms
characteristic hollow profile in agreement with the experiment.

144/196

Collaboration on visualization methods with University of Hyogo,
Kobe University, Konan University, Kyoto University, Nagoya University,
JAMSTEC, National Defense Academy, Osaka Prefecture University.

• A game development engine, ex. Unity, has potential as a common
development environment of visualization software because it deals withvarious visualization devices, such as head mount display, smartphone, CAVE
and so on. We research the utilization of Unity for scientific visualization.
• In-situ visualization library VISMO is developed to perform visualization process
together with simulation on the same supercomputer.
• We visualized the orbit data by solving the Einstein equation in uniform andanisotropic universe model.

• The CAD data of the periphery devices of LHD can be easily installed to the
VR visualization content “LHD vessel”.
• The point cloud data is visualized by CompleXcope.
• It was found that each orbit rotated spirally in 3d space.

skip

145/196

NINS program of Promoting Research by Networking
among Institute “Hierarchy and Holism in Natural
Sciences” performs PIC simulations of relativistic jet
launched by black holes• Global structure of relativistic jet launched by black holes is calculated by PIC code
without using MHD approximation assumed in most of works on astrophysical jet.
PIC simulation(spine-jet formation)

Kawashima+ in prep.

Jet direction

Observation(Spine-sheath jets are found.)MHD simulation(Recently, sheath jets are
successfully reproduced.)• Mushroom instability (MI), which is a transverse electron-scale instability in relativistic
shear flow, induces intermittent magnetic reconnections (MRs) in the jets.
• MI itself and MI-driven-MRs lead to the convergence of electrons toward the jet centerwith particle accelerations, which can explain the spine-jet structure observed in M87.

146/196NINS cross-disciplinary study on Turbulence,
Transport, and Heating Dynamics in Laboratory &Solar/Astrophysical Plasmas: SoLaBo-X (2019~)• In NINS program of cross-disciplinary study for young researchers, collaborations
among NIFS, NAOJ, and the other Universities are accelerated.
SoLaBo-X project (Solar + LaBoratory + Cross-disciplinary)• Utilizing the advantage of high-resolution observations/simulations in laboratoryand solar-plasma researches, the turbulence-related transport and heating
dynamics are explored through the mutual exchange of knowledge & scheme.
Similarity of intermittent bursty transport

Visualization experiments forsolar turbulent convections:comparison with simulations
application to Deep Learning

Avalanche in fusion plasma
Depth

CZ: convective zone
RZ: radiative zone

Avalanche in solar interiorTime----> Reynolds number

Nakata et al (NIFS), Katsukawa et al (NAOJ), + the other Univ.

147/196

NINS program for cross-disciplinary study“Investigation of the laws on the relation between aspatiotemporal neuronal activity and connections oflocal neural circuits in an active brain” contributes toestablishing the novel methodologies for investigation
into global dynamics on a cerebral cortex.
• Novel experimental
and mathematicalmethodologies forinvestigation into
global dynamics on a
cerebral cortex havebeen established.
• As a topic in this program, the large-scale simulations of neural circuits which
include 1M neurons have been performed in order to develop the huge-scale
simulation model of global dynamics on a cerebral cortex with the macromicro interlocked (MMI) algorithm.
7 collaborators from 2 domestic universities, 2 foreign universities (USA), and3 institutes (NIPS, IMS, and NIFS).

skip
148/196PWI simulation is applied into semi-conductor skip
processing as industry‐university joint research• Multi-scale and hybrid simulation approaches for Plasma-Wall Interaction(PWI) can be applied into the other plasma-material interaction phenomena.
• Beginning 2018, industry-university joint research on semiconductor
processing began with the Toshiba Memory Corporation (currently Kioxia).

• The contents are technical provisions related to simulation methods.
• The first result is as follows:
T. YAGISAWA, S. KATO, A. TAKAYAMA, and A. M. ITO,
“First Principle Molecular Dynamics of fluorocarbon molecule injection into Si
surfaces”,
The 40th International Symposium on Dry Process (DPS2018)
Nagoya, Japan, November 13-15, 2018.
In addition, under the support program of NINS for cross-disciplinary study,
the application of PWI simulation has been currently expanded into
astronomy, biology, and so on.

149/196[3]-(3)150/196

3. Promotion of cooperation and collaborations(3) Does the NSRP contribute to international cooperation including
ITER, BA activities, and others through international collaboration
activities?
• Director of the NIFS Rokkasho Research Center is serving
concurrently as IFERC Project Leader.
• NSRP members are undertaking collaborative research projects
for JT-60SA.
• NSRP members are participating in the ITER/BA activities.
• NSRP contributes to international collaborations with US, EU,
China, and Korea.

151/196

Cooperation with ITER and BA activities
Activities at the NIFS Rokkasho Research Centre• At Rokkasho village in Aomori prefecture, International Fusion Energy ResearchCentre (IFERC) project is implemented as well as IFMIF/EVEDA in the framework of
BA activities, in order to contribute to ITER and to the early realization of DEMO.
• The IFERC project is promoting 3 sub projects; DEMO Design and R&D Coordination
Centre, Computational Simulation Centre (CSC), and ITER Remote Experimentation
Centre (REC).
DEMO R&D Bldg.
DEMO Joint Research
Bldg.

NIFS Rokkasho
Research Center
inside of JAEA Aomori
Res. & Dev. Centre.

CSC & REC
Bldg.

Administration & Research Bldg.

IFMIF/EVEDA Accelerator Prototype Bldg.

• The roles of the NIFS Rokkasho Research Centre (RRC) are to support the cooperation
between NIFS/universities and BA activities, and to prepare the environment for promoting
a variety of collaborative researches between NIFS/universities and BA activities.
• For such purposes, the head of the RRC is undertaking work as the IFERC project leader
from 2010/9 and the RRC has been moved into JAEA Aomori Research and Development
Centre on 2012/4.
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Director of NIFS Rokkasho Research Center isserving concurrently as IFERC Project Leader (PL)skip

Tasks of PL• To coordinate activities of EU and JA Implementing Agencies (IAs).
• To prepare input documents of IFERC Project Committee (PC) for reporting activities andgetting recommendation of PC to invite the Steering Committee (SC) to approve
proposals. (In spring PC and SC, the main input documents are the annual report of thelast calendar year and updated project plan. In autumn PC and SC, those are work
program of the next calendar year and summary report. Update of Value Estimates andAllocation of Contributions of the Parties is proposed just in case.)• To hold and attend various managerial and technical coordination meetings (TCMs). (ex.
Extended Project Team Meeting in almost every two weeks with Fusion for Energy (F4E)).
• To support preparation and implementation of the Procurement Arrangements.

Other recent activities as PL:• To support the successful closing of IFERC project in BA Phase I at the end of Mar. 2020,• To compile the Final Report of Demo Design Activity,• To compile the Final Report of REC Activity,• To complete and report the accounting of credit values,• To support the creation of IFERC project plan for BA Phase II from Apr. 2020 to Mar. 2025,• To disseminate IFERC activity to public via website: https://www.iferc.org
153/196

NSRP researchers are contributing to IFERC CSC andcollaborative research for JT-60SA and IFERC REC• NSRP members implemented more than 10 simulation projects every year on
IFERC CSC Helios as principal investigators (summarized in the Table).
• NSRP members contribute to the committees for the IFERC CSC.
• NSRP researchers are undertaking collaborative research projects for JT60SA and IFERC REC.
IFERC CSC Helios (2012-2016)
Cycle

EU-JA allocation (80%)

JA domestic allocation (10%)

4th cycle

10(Dec. 2014 - Nov. 2015)

6(Apr. 2015 – Mar. 2016)

5th cycle

8(Nov. 2015 – Dec. 2016)

4(Apr. 2016 – Dec. 2016)

IFERC CSC JFRS-1 (June 2018- )Cycle

Project

General (=10k node hours/project)

FY 2018

10

0

FY 20196

1
154/196

NSRP members are participating in and contributing to
ITPA topical groups• Three NSRP researchers are the members of ITPA (International Tokamak
Physics Activity) topical groups Pedestal and Edge, Energetic Particles, andIntegrated Operation Scenarios.
• The number of participants from NSRP for each topical group meeting issummarized in the Table.
Year

Pedestaland Edge

Energetic
Particles

2013

1

2

2014

2

MHD

Integrated
Operation
Scenarios

Transport
andConfinement

Total

3
2

2015

2

1

3

2016

2

1

3

2017

1

1

2

2018

1

1

2

2019

4

1

5
155/196

Collaborations on GKV:
1. Quantitative validations in JT-60U
2. D-T-He transport in ITER-like plasma
1. Ion and electron turbulent transport was investigated by gyrokinetic
simulations based on a realistic JT-60U equilibrium [Nakata+(NF2016)].
•

GKV simulations well reproduce the experimental results of the turbulent flux.

2. Multi-ion-species gyrokinetic simulations were carried out to examine theturbulent transport of D, T, and He-ash in ITER-like plasmas [Nakata+(IAEAFEC2016, IAEA-TM2017)].
•

Imbalanced particle transport of D and T is found in 50%-50% mixed plasma.

ITER-like

156/196

Collaborations on MEGA:
1. Abrupt Large-amplitude Event in JT-60U
2. MHD instabilities in JT-60SA plasmas
1. Abrupt Large-amplitude Events (ALE) observed in JT-60U plasmas weresuccessfully reproduced with the MEGA code [Bierwage+(Nat.Comm.2018)].
•

The simulation predicted the excitation of multiple modes at ALE, which wasdemonstrated by the analysis of the experimental data.

2. Pressure driven and fast-ion driven MHD instabilities were investigated for JT60SA plasmas during current ramp-up with off-axis NBI[Bierwage+(PPCF2017)].

[Bierwage+(IAEA2016, Nature Comm.2018)]

157/196

Collaborations on EMC3-EIRENE and MIPS:
1. Divertor footprint in JT-60SA with RMP field
2. ELM mitigation in JT-60SA with RMP field
1. Divertor footprint in JT-60SA with RMP field was obtained for the first time by
EMC3-EIRENE code.
• Splitting of the flux distribution was obtained corresponding to the toroidal mode
number of the RMP field.
2. The effects of RMP field on the Edge Localized Mode (ELM) in JT-60SA were
investigated with MIPS code.
• ELM mitigation with RMP field was demonstrated.
Particle flux on theoutboard divertor

Heat flux on theoutboard divertor

Stored energy
loss is mitigatedwith RMP.

Splitting

158/196

Assessments of RMP and error field effect on plasma
rotation in JT-60SA and ITER
Collaborate with QST• 3D magnetic perturbation in tokamaks is expected to affect the plasma
rotation through neoclassical toroidal viscosity (NTV).
• Neoclassical code FORTEC-3D evaluates NTV in JT-60SA and ITER, andthe toroidal rotation profile is calculated by integrated transport code
TOPICS.

ITER

JT-60SA• Several patterns of RMP fields in JT-60SA and the NTV in each case are
study for JT-60SA research planevaluated• Toroidal rotation profile changes according to the NTVs from error fields caused
by toroidal ripples, ferromagnetic inserts, and test blanket modules in ITER.

•

159/196

The NSRP plays a central role in promoting US-Japan
collaboration, wide-ranging collaborations with European
institutions, A3 foresight program (Japan, China, Korea),
and other international collaborations in fusion plasma
simulation• NSRP plays a major role in collaborations with the United States
through Joint Institute for Fusion Theory (JIFT) activities: workshops
and exchange of scientists• NSRP promotes wide-ranging collaborations with European
institutions.
• Collaborations with China and Korea are progressing under the A3
foresight program and post-CUP (Core-University-Program).

160/196

NSRP conducts collaborations with US throughJoint Institute for Fusion Theory (JIFT) activities• NSRP supports US-Japan workshops and exchange scientists to promotesimulation science based on fusion plasma research.
• NSRP contributes to management of JIFT activities as a host Institute.

JIFT Steering Committee
US Members

Japanese Members

F. Waelbroeck (IFS)—Co-Chairman
A. Arefiev (IFS)—Co-Exec. Secretary
D. Spong (ORNL)
J. Mandrekas (DOE)

H. Sugama (NIFS)—Co-Chairman
S. Ishiguro (NIFS)—Co-Exec. Secretary
S. Murakami (Kyoto)
Y. Sentoku (Osaka)

JIFT Advisor Committee
US Members

Japanese Members

A. Aydemir (IFS), P. Catto (MIT), B. Carreras(BACV Solutions), V. Chan (GA), B. Cohen(LLNL), W. Horton (IFS), W. Tang (PPPL), and
P. Terry (UWM)

Y. Todo (NIFS)
Y. Kishimoto (Kyoto), Z. Yoshida (Tokyo)
T.-H. Watanabe (Nagoya), M. Yagi (QST)

161/196

NSRP actively conducted JIFT workshops
and exchange scientists in 2016-2019

162/196

Collaboration with PPPL and Princeton Univ. haspromoted magnetic reconnection studies.
• NINS-Princeton collaboration has promoted studies of magnetic
reconnection in laboratory plasmas and the Earth magnetosphere.

• PIC simulations have reproduced the experimental data from MRX andobserved results in the magnetosphere by MMS satellites .
• We have found the energy partition between fields and different particle
species and a mechanism for electron heating in high guide field.
163/196

Development of Global Gyrokinetic Code toward CoreEdge Coupling Simulation of Helical Fusion Devices• We are developing a global gyrokinetic code, XGC-S, using particle-in-celland finite element methods for core - edge coupling simulations of Helicalfusion devices in collaboration with PPPL.
• We employ extended 3D-VMEC equilibria and field-following triangularmeshes that cover the entire region inside the vacuum vessel.

• Basic benchmark tests on neoclassical transport, linear ITG and high-energy
particle confinement have been performed.
• Results are consistent with those obtained by using other simulation codes in
164/196
NIFS, i.e., FORTEC-3D, GT5D and HINT2.

Core formation of asymmetrically driven cone-guided
targets have been simulated by IMPACT-3D code
• An Energy absorption profile for one laser beam is calculated by the raytracing code, and it is interpreted as a pressure perturbation profile.
• The pressure perturbation profile is duplicated and overlapped on the spheresurface as initial conditions, and fully 3D hydrodynamic simulations are
performed by using IMPACT-3D code.

skip• Core formations for 12 laser beams without the cone and 9, 6 or 4 laser
beams with the cone are investigated.
• The maximum density and areal density are measured for each case, andimplosion degradations due to asymmetry are evaluated.

165/196

NSRP collaborations with EU on the neoclassicaltransport analysis in stellarator / heliotron• Neoclassical transport theory / simulation collaborative researches on LHD,
W7-X, TJ-II ,etc. have been carried out.
temperature screening( and plateau regime)
inward pinch by<0,

Temp. screening term cancels
the inward -pinch term

impurity-holecondition (LHD )• Possibility of moderation of impurity accumulation in high- , negative- plasma
is shown by neoclassical transport theory (left). [Velasco et al, Nucl. Fusion 2016]• Confirmation of ambipolar- measurements (XICS and CR) with three NC
validation for “neoclassicalsimulation codes in W7-X high- discharge (right)
optimized” design concept. [Pablant et al, Phys. Plasmas 2018]
166/196

Collaborations in kinetic simulation studies
with Europe

skip• Neoclassical simulation studies for impurity particle transport in LHD impurity
hole plasma, and modeling studies of turbulent transport in stellarators were
performed under the collaboration with IPP Greifswald and Eindhoven
University of Technology.

• Flux-surface potential variations 1
cause more inward Gc
which is observed in local NC transport simulations.
• This means that more precise physics should be considered to explain the
impurity hole generation in terms of neoclassical transport.

167/196
1

Collaborations with Max-Planck IPP and FZ Jülich havepromoted many researches on divertor modeling• EMC3-EIRENE code developed in Max-Planck have been applied to• plasma-neutral interaction study with different divertor geometry in LHD• impurity transport modeling with gas puff in LHD• dust particle transport in LHD• JT-60SA divertor modeling with RMP• Heliotron J divertor modeling• and many other works• Impurity transport and plasma-wall-interaction code ERO2.0 developed in
FZJ has been introduced to LHD this year and will be applied to impurity
deposition researches in LHD

neon radiation in LHD

JT-60SAwith RMP

Heliotron J
168/196

Collaboration with Dalian University of Technology
has revealed toroidal asymmetry effect of neon puff
• Impurity transport study of EAST SOL/divertor plasma has been performedby using EMC3-EIRENE code.
• Neon puff at “I2” and “I3” near the strike point on the divertor causes
toroidally asymmetry heat flux reduction on the divertor of the same side as
the puff because of localized neon transport.
• On the other hand, the puff causes symmetry and weak reduction on the
opposite side divertor plate because of global neon transport from the one
side to the other side.
• This result suggests possibility of strong heat load reduction with multiple
neon puff distributed over the entire toroidal region.

inboarddivertor

inboarddivertor
169/196

Collaborations with China and Korea
in A3 Foresight Program and Post-CUP• ASIPP• Energetic particle driven instabilities in EAST tokamak (collaboratingwith Y. J. Hu, Y. B. Pei, and N. Xiang)• Divertor plasma modeling (with G. J. Niu, Q. Xu, Z. S. Yang, G. N. Luo)
• Plasma response modeling for magnetic field structure induced by
RMP (with Y. Liang)
Comparison of spatial profile for
an Alfvén eigenmode in EAST
tokamak between (a) M3D-K and(b) MEGA.
[Hu+(PoP2016), Pei+(PoP2017),
Pei+(PoP2018)]• DLUT (Dalian University of Technology)• Effects of energetic electrons on Alfvén eigenmodes with MEGA (with J.
L. Wang, Z. X. Wang)• Divertor plasma modeling with EMC3-EIRENE (with S. Dai)

170/196[4]171/196

4. Human resources development

Does the NSRP contribute to the development of humanresources required for maintaining high-level simulation
research activities toward the future?

The NSRP contributes to the development of human resources
required for maintaining high-level simulation research activities
toward the future:(1) Education programs of Sokendai and of the other graduate
schools at Nagoya, Nagoya Inst. Tech., etc.
(2) Cooperation programs with high schools in science education(Super Science High School program)(3) Sokendai Summer School(4) Sokendai Asian Winter School on Simulation Science

172/196

NSRP contributes to the development of human resources
through education of graduate students• NSRP supports simulation research of graduate students (from Sokendai,
Nagoya Univ., Nagoya Inst. Tech., etc.).

• Graduate students made 28 presentations at international conferences in
2015-2019.
• Graduate students and postdocs published 27 and 10 papers, respectively,
as first authors in refereed journals during 2016-2019.
173/196

Cooperation with high schools in science education, SSH,
has been promoted in collaboration with NSRP
• Cooperation programs with high schools in science education have beenpromoted at NIFS with the help of the “Super Science High School” (SSH)
program.

• More than 400 students come to NIFS for this program each year.
• The NSRP has contributed to three subjects in the program:‘’Numerical Simulation,” “Programming and Visualization,” and “Virtual Reality”

174/196

Sokendai Summer School provides graduate students with
opportunities to experience the most up-to-date research
at NIFS• The purposes of this School are to gain publicity for fusion science and tolook for the students who would like to become researchers in the field.

• The students experience research activities under the guidance of Sokendaiteachers and students, and present their activities at the meeting.
• The NSRP staff propose subjects and accept from two to four students ineach subject.

175/196“Sokendai Asian Winter school” provides students andyoung scientists from Asia with an opportunity to study
leading-edge fusion science• The school gives lectures on plasma physics, fusion science, simulation,
experiments.
• The school was held in Thailand from 2016.

176/196[5]177/196

5. Future Plan

Is the future research plan suitable for progressing toward
the goal of the NSRP? Does it also contribute toestablishing the future plan of the National Institute for
Fusion Science?

The NSRP plans to further advance the researches for improving,
integrating, and validating simulation codes with the upgraded
Plasma Simulator toward construction of the Numerical Simulation
Reactor which contributes to designing high-performance helicalfusion reactor.
• Each of eight task groups has a roadmap which shows specifictasks to be solved through domestic, international, and interproject collaborations.
• The NSRP directly contributes to optimized configuration study
for the Next Generation System (NGS) in the future plan of NIFS.
178/196Three-step plan of the NSRP:
1.
2.
3.

To develop simulation codes for various physics elements of fusion plasmas
To integrate and validate simulation codes for treating multi-scale and multiphysics phenomena
To construct a system of codes [=Numerical Simulation Reactor (NSR)] forcontributing to designing high-performance helical fusion reactor

Roadmap for realizing Numerical Simulation Reactor (NSR)
2nd mid-term

3rd mid-term

4th mid-term

2010

2016

2022

2028

Development ofsimulation codes
for various physics
elements
constituting fusion
plasmasExtension and integration ofcodes for treating multi-scale
and multi-physics phenomena
V&V and application of codes
by collaboration withexperiments and engineering

Further development
and completion of
NSR for contributing
to designing highperformance helicalfusion reactor

2019

179/196“Plasma Simulator” is going to be upgraded to a new system:

total peak performance more than 10 Petaflops in June 2020
Plasma Simulator is going to
be replaced to a new system inJune 2020.
The peak performance of the
new PS system is more than fourtimes of the current FX100
system (to be operated until theend of Feb. 2020.)

HITACHI SR16000/L2(peak speed:77TF
memory: 16TB
period: 2009 – 2012)

HITACHI
SR16000/M2(peak speed: 315TF
memory: 40TB
period: 2012 –2015)

FUJITSU PRIMEHPC FX100(peak speed: ~2.6PF memory:~81TB
period: 2015-2020)

NEC (model name TBD)
(peak speed:~10.5PF,
memory:~200TB: period:2020-2025)

Peak performance (Tflops)
10000
1000
100
10
1
0.1
0.01
0.001

180/196

Plasma Fluid Equilibrium Stability Group
Objectives :• Further development of equilibrium code and application to 3D plasmas• Identification of key stability physics in LHD and quantitative prediction of stability boundary for next
device in NIFS

objectivetask

2017-2019 2020

2021

2022

20232025

New PS
Furtherdevelopment ofequilibrium code

Incorporation offlow andanisotropicpressure

Flow incorporation

MHD stability ofquasi & standard
interchange
mode

Extension of MHD
models andcomprehensive
understanding of
toroidal plasmas

Incorporation of
kinetic ions &plasmoidanalysis
LES withsource andsink

Incorporation of anisotropic pressure

Divertor field line calculation of heliotron & modular systems

Identification of
key stability
physics andquantitative
prediction ofstability boundaryfor next device

Next generation
device design

20262028

Analysis of global
flow effects

D shape effects

Landau damping
effects

Effects of global
flow and islands

Combining neoclassicaltransport

Combining turbulencetransport

Diagram of standard &quasi interchange modes

Optimization of helical,
poloidal, and modular
coils

Kinetic thermal ion
effects on linear stability

Analysis of pellet plasmoid in LHD

Pellet injection in LHD plasma with an island

Concept-proof
of LES of XMHD

Kinetic thermal ion andenergetic ion effects

Kinetic thermal ion effects
for nonlinear evolution

CITM study by LES of XMHD with
new SGS model for microscopic
effectPressure-driven mode
study by new LES
model

Full model extension
for two-fluid
equations

181/196

Energetic-Particle Physics Group
Objectives :•••Validation of MEGA code on LHD and tokamak plasmas.
Improve MEGA code with ICRF and drift waves for predictive simulation of burning plasmas.
Simulations of high-frequency waves and automatic experiment analysis with GNET.

objective

task

2016

Understandingof EP driven
instabilities

Simulation
study of AE
and GAMNF NJP
EP critical distribution/AE burst

Validation andverification

Comparison
withexperiment,
theory, andother codes

Codedevelopment

Developmentof MEGA
and/orkinetic codes

2017

2018

2019

2020-2023

New PS

2024-2028

PS upgradedNF

AE with ICRF
AE/ITG/ZF
NF NF
PRL
EGAM in 3D equilibrium
EP distribution F Higher frequency
EIC
waves
ICE and LHW
PFR
PFR
NF NF
PoP
V&V on LHD deuterium experiment
V&V on LHD experiment
NF

V&V on CFQS
NF
NF
NF CPC
NatureComm.
V&V on tokamaks
V&V on JT-60SA
V&V on JET DT

NF PPCF
Kinetic effects of bulk plasma and energetic
ICRF fast ions
Reduced EP
electrons
transport model
NBI in time-evolving
MHD with drift waves
plasma (GNET)
Automatic exp.
NF
analysis (GNET)
182/196

Neoclassical & Turbulent Transport Simulation Group
Objective

Task

2016

2017

2018

2019

2020

New PS
2021

Kinetic transport modeling for
applying to integrated
simulations

Construction of numerical simulation codes for core plasma transport

Large-scale neoclassical & gyrokinetic
simulation studies

LHD deuterium experiment

Improved collisionmodel (PoP2019)

NCL simulation of Er
in W7-X (PoP2018)

PS upgraded2026-2028

2022-2025
LHD-U
experiment

deuterium exp.

NCL simulation of high Z impurity transport

NCL toroidal viscosity (IAEA2018)

Study of impurity hole in LHD plasmas

NCL impurity accumulation in LHD (NF2017)
Global & F1 effects on
NCL & GK analyses ofGK analysis of
NCL impurity transport
Multi-ion-species in impurity transport in LHD(IAEA2018 & ISHW2019)
Global GK simulation of Er profile effects
LHD (PPCF2017)
Multi-species ITG- Global turbulent & neoclassical simulations for multi-ion-species plasmas
TEM turbulent
Extension of GT5D for
Comparison of global & local ITG simulations oftransport in ITER
helical systems (PoP2018)helical systems
Global GK simulation of interaction(IAEA2016)
between NCL & turbulent transport
Study of isotope effects on turbulent transport

in LHD plasmas

GK simulation of isotope effects on ITG & TEM
turbulence in LHD (PPCF2016 & PRL2017 & PPCF2018)
Multi-machine GK
Validation of GK
simulation against transport analysis of
JT-60U (NF2016) Heliotron J & LHD (NF2017)

Construction of reduced model of
turbulent transport based on gyrokinetic
simulation
Turbulent ci modelin LHD including ZF
and kinetic electron
effects (PFR2017)

Local GK simulation of Er shear
effects on ITG & TEM turbulence

Extension of reduced gyrokinetic transport models/ Advanced optimizations of turbulence & zonal flows/ Application to NGS creation research
Extension of QL models to include Ershear, multi-species, global profiles, …
Applying turbulent transport models to
optimization of helical configuration

ci & ce models
and QL models ofGe, qe & qi in LHD(PoP2019 & ISHW2019)

Unifying largescale simulation
and AI
Applying QL
models to transport
simulation

Development of integrated transport code including kinetic models / with AI
Applying ci & ce models to
turbulent transport simulationof LHD (PFR2019)

183/196

Peripheral Plasma Transport Group
Objectives :•Three-dimensional transport analysis of edge plasma in LHD [2,4]•Modeling study on edge plasma physics, core/edge coupling, and plasma-wall interaction [1,3]objective

Transport
analysis ofparticle andenergyTask

Validation
withexperiment;
Developmentof 3D edgetransport
code20172019

2020

2021

2022

New PS

Impurity seeded plasma modelingand validation with LHD experiment

Detach modeling of NAGDIS-II

20222025

20262028

Hydrogen mol./atomic proc.

Erosion/transport/redeposition modeling of LHD
Bolometer data analysis, application to experiment

Divertormodeling /plasma-wallinteraction /dust dynamics

Collaborations Dust transport in LHD
Validation with experimentwith other
JT-60SA modeling with RMP, and toroidal coil modulationgroups /institutes
Heliotron J modeling
Various Heliotron J configurations

Modeling
study towardprediction andoptimized
divertor

Devitor design/ Transportmodel
development

Validation with experiment

NAGDIS-II modeling
EAST divertor modeling
Divertor concept study
for the next generation device

Particle and energy transport
in divertor plasma

Divertor design study

FFHR divertor
184/196

Plasma-Wall Interaction Group

Objectives :• Tungsten divertor physics; analysis of tungsten atomic level behavior by plasma irradiation• Expansion to other materials from tungsten to investigate future plasma facing materials for
DEMO reactor.

objective task

2016—20192020-2023

2024-2029

Fuzz formation

Tungstendivertorphysics(Nano
structureformation,
Hydrogenrecyclingmodel)• toward versatile multihybrid (5 pieces or more)• BCA-MD-KMC multi-hybrid sim.
structurechange underirradiation• On the fly KMC(KMC-MD hybrid)

New divertor
materiaｌ
Hydrogen
Recyclingmodel• Z-Universal potential model
development (MD & DFT)

• Construction of Prototype MD model(graphite+hydrogen)plasmaapplication

Industryuniversity joint
research

Effects ofRadioactive
material

Tritium
disintegration
effect ofbiopolymers• Construction of MD model• hydrogen isotopes(tungsten+hydrogen)• Other materials• Data collections by MD (SUS, beryllium etc)

• with Toshiba Memory Corporation*The details is non-disclosed for the contrast with TMC.
*Schedule is not decided yet, depending to TMC.
・First MD modeling of DNA ・Expanding to other bases of ・Expanding to otherdisintegration by tritiumDNA
DNA or Proteins(Guanine of telomere structure)
185/196

Integrated Transport Code Group

Objectives :••Further development and application (validation) of the integrated transport analysis suite, TASK3D-a [2]Facilitating the development of predictive version, TASK3D(-p), and its programmatic application forsteady-state higher-performance LHD plasmas and FFHR design study [2,4] LHD (deuterium) experimentobjective

Analysis
suite,TASK3D-a

task

2016

2017

2018

2019

Furthera02-> a03, a04
extension of • Extension of NBI modules (to be compatible to LHD
deuterium experiment)
physics• Loose coupling to large-scale simulation codes (FORTECmodules and
3D, PENTA, SFINCS, and GKV-X) for their smootherapplications
applications to and benchmarking activities with LHD
plasmas(validation)
against LHD • Easy-to-use neutron emission rate calculation tool
established(deuterium)• TASK3D-a has been basis for studying
experimentenergetic particles behaviour in LHD

deuterium plasmas (extensive application
for systematic analyses, TASK/FP,
CONV_FIT3D)

Commonmodules Prediction

towardsteady-statehighPredictive performance
LHD andsuite,TASK3D(-p) FFHR

2020-2023

2024-2028• Further contribution forinvestigating isotope effectand energetic particles
behaviour (database creation
for LHD deuterium
experiment)• Further integration (ex., coreedge coupling, impurities,
enhancing collaborations withother groups in NSRP)• Strengthening activities
related to burning plasma
issues (towards Numerical
Simulation Reactor, NSR)

Validations against LHD plasmas
Implementation of steady-state issues

Increasing relevance (H/He comparison, isotope study)• Comparison among several• Deduction of relevant transport model(s) utilizing LHD
transport models to induce theplasmas : Gyro-Bohm, Gyro-Bohm x ∇T, Zeff, Aeff (forrelevant model, and full
deuterium plasmas)
implementation of data
• Consolidation of GNET and GNET-TD for more accurate NBI
assimilation (all towards NHTR)
heating analyses• Link to “data-driven Science”• Data Assimilation (Kyoto U. • FFHR-d1 start-up to wholeduration simulation (as a– The Institute of Statistical
prototype NHTR)
Mathematics (ISM) – NIFS)• Collaboration with Fusion Engineering Research Project• Plasma control scenario(FERP) : implementation of TASK3D-a modules for energydevelopment (possibly withbalance analysis, start-up scenario
Basis for NHTR
data-driven community)• Demonstrationof data
assimilation forsteady-state
operation.

Provisional version, evolution of 186/196
NSR

Multi-hierarchy physics group
Objectives :• Whole-volume modeling including core and edge regions of helical fusion devices• Renormalization of microscopic and kinetic processes to XMHD by employing SGS model for LES.
• Clarifying physics in primitive processes, which supports the above models, by using PIC simulations.
Objective

Task

2015-20192020 New PS 2021

2022

Core-edge
coupling

Gyrokine
tic-PIC

Basic global gyrokinetic
simulation in helical coreregionDevelopment of gyrokinetic
field solver for stochastic
regionVerification of edge simulation

Neoclassical /electrostatic turbulent
simulation in helical edge
regionMain achievement 2015-2018:
・Development of SGS model for LES of XMHD (2016)
and application for instability study f LHD (NF 2017)

Multihierarchy

Extended MHD(XMHD)

Concept-proof of LES of
XMHD model(MUTSU/MINOS)

Main achievement 2015-2018:
・Extension of XGC to non-axisymmetric geometries,
examination of GAM oscillation and particle loss at
the material wall (IAEA-FEC2018)

Clarifying
physics inprimitive
processes

2023

2024-2028

PS upgrade

Core-edge coupling
phenomena with
impurity transport
and transportbarriers

・Parameter-renormalization
for primitive processes for
XMHD-LES (MUTSU/MINOS)
・Development of full two-fluid
code for study of LES

Study of nonlinear
・XMHD-LES /full twofluid LES SGS model
evolution of shortoptimization forwave instability of
instability simulations
magnetized plasmas(MUTSU/ MINOS) andby fully two-fluid LES
basic study of full twoProviding basic data fluid LES
Providing basic data
Reconnecti
on by 3D
PASMO

PlasmaHeating

Reconnection by 2D
PASMO

Reconnection bylarge-scale 2D
PASMO

Boundary Layer

Filament by p3bd /Detachment by PAMCADE

Filament by up3bd /Detachment by PAMCADE
including recombination

Main achievement 2015-2018:
・Ion heating mechanism in an ST (IAEA-DEC2018, PoP2019)
・Impurity ion transport by filaments (NF2017, NME2019),
Isotope effects (IAEA-FEC2018) and kinetic effects (Plasma
2018, PoP2019) on filaments

Plasma merging in whole
poloidal surface by 2D
PIC

Plasma merging withlarge-scale PIC in a
curved geometry

Radial and paralleltransports during
detachment state by
up3bd-PAMCADE

Connection of
up3bd-PAMCADE toglobal codes (e.g.,
XGC-S)

Collaboration with Peripheral Plasma Transport Group187/196

Simulation Science Basis Technology Group

Objectives :• Developing methodologies and techniques of scientific visualization and simulation• Contribution to the design of FFHR/DEMO reactor

objecti taskveVR
Visualization(Vis.)
Research

2016-20192020-2023

2024-2029

Upgrade of
VR system• Upgrade of projectors, Unity and MiddleVR,
HMD (2016)• Upgrade of PC cluster (2018)• Upgrade of Linux system (2019)• Replace of tracking system• Upgrade of PC cluster system• Upgrade of VR projectors• Upgrade of Linux system

Sophisticat
ion ofsoftware• 3D sound (2016)• Porting of vlhd to HMD (2017)• LHD (2018)• Impurity radiation (2018)• Visualization of magnetic field lines (2019)• GK visualization (2019)
Press Release• Vis. Animation
JSST Award• Animation of robot systems
NF• Structural analysis
ITC• Virtual measuring probe• Utilization of game development engine• HMD, WebGL• Utilization of machine learning• Additional integration ofsimulation, experiment anddevice data.

• Animation based on mechanism analysis
results• VR visualization of fusionplant

VR vis. of
CAD data
In-situ
Visualization

Developmen
t of Parallel
Programing
Language• Development of point cloud• Implementation of user interface• Interface module• Functional extension in response to requests• CAVE
ITC• Visualization of particle
AAPPS-DPP(Invite)• Optimization for FX100
ITC• Functional extension
Developm
ent of XMP• XMP workshop, Omni compiler v1.1.0 (2016)• XMP workshop, XMP specification v1.3, Omni
compiler v1.2.2 (2017)• XMP workshop, XMP specification v1.4, Omni
compiler v1.3.2 (2018)• Functional extension in
response to requests• Consideration of XcalableMP(XMP)
specification and extension for
OpenACC(XACC), and performance
evaluation of Omni compilers

188/196

NSRP contributes to establishing the future plan of NIFS
through applying simulation codes developed in NSRP
to physics & engineering studies of optimized
configuration for the Next Generation System (NGS) of
the NIFS future plan
• Optimization of equilibrium for reducing NCL andturbulent transport• Turbulence & Zonal flow modeling based on GK simulation• Comparative study of modular-coils & helical-winding coils
type optimizations• Investigation of flexible divertor structures
189/196Contributions to optimized configuration studies in
Task force for next research project• LHD has been operated for >20 years, and the future plans after LHD havebeen discussed since Apr. 2017 in Task force for next research project(次期計画検討チーム)• Related research activities are initiated: NGS team & HTS team
NGS: Physics & Engineering studies towards advanced optimizations.
HTS: R&D of High-Temperature SC coils for application to the next device.
Simulation codes developed in NSRP are utilized in NGS activities.
Schedule towards the next device*still discussed in Task force for next research project 190/196

Co-creation framework in optimized configuration
research activities
Physics studies for advanced concept• NL-GK based turbulence modeling for stellarator optimizations• Flexible divertor configuration (leg-type & island-type)• Comparative study of modular-coils & helical-winding coils type optimizations
Engineering study with trial model case (coils, Vacu. Vessel, etc.)• Trial-model-case engineering design with conventional schemes.
• Identification of engineering limits and boundary conditions.
• Design of heating systems, fundamental & advanced measurement system.

Co-creation framework (mutual
feedbacks)

191/196

Turbulence & Zonal flow modeling for nonlinear
optimizations• Based on the gyokinetic simulation & modeling studies in NSRP, a new turbulence
optimization model (proxy approach) is constructed.
• Extended turbulence proxy includes nonlinearity and ZF effects, which is beyond
the conventional linear proxy approaches.
• It is now implementing to the optimizer code (e.g., STELLOPT).
ZF modeling w.r.t geodesic curvature

Qi/QGB
NL-GKV check fortransport reduction &ZF enhancement inlower geod. curv. caseNakata JIFT-WS2019, ISHW2019, EUROfusion Sci. meeting 2019

192/196

D shape coil current improves the divertor clearance.
• Effects of the D shape deformation are investigated in the optimization ofheliotron configurations.
• The vacuum magnetic field with the current in the D shape coil which isconsidered to be installed just inside the helical coils is analyzed.

skip

helical coils
plasmaR

D shape coil
• The D shape coil current effectively enhances the divertor clearance.
• The effect is quite useful in the design of a smaller size device.
• On the other hand, the minor radius of the plasma is decreased due to thecurrent.
193/196

Investigation of flexible divertor structures in a single
optimized plasma• In optimized stellarators, the divertor structure is often limited due to the complex
coil configuration and the low-robustness against plasma beta.
• Promoting the optimized external coil study, the flexible control of leg-type divertor
and island type divertor is investigated.
• Divertor properties are evaluated by e.g., the edge transport code (EMC3).
Sweeping the diverter-legs from Quasi-Symmetricstellarator (e.g., QH)

Nakata ISHW2019, Suzuki JSPF2019, Kawamura JSPF2019

194/196

Optimization scan of the trial equilibrium for trial
engineering design studies• For engineering study with a trial equilibrium, optimization scan with STELLOPT
and the evaluations of physical properties with drift/gyrokinetic, MHD codes arecarried out.
• A QO-like neoclassically optimized equilibrium(Ap=7, N=4) are systematicallyPre-engineering design study is accelerated.
selected as a trial configuration.
An example of STELLOPT scans
Trial configuration
Heating port
designEM force analysis forthe coils and support
structures
Matsuoka, Ichiguchi, Yamaguchi JSPF2019

195/196

Summary of Future Plan
The NSRP plans to further advance the researches for improving, integrating, andvalidating simulation codes with the upgraded Plasma Simulator toward
construction of the Numerical Simulation Reactor• Further improvement and integration of codes by collaboration among task groups
and collaborators from other universities and institutes• Validations of codes by comparison with experimental results of LHD and otherdevices by collaboration with the LHD Project and other institutes• Contribution to further progress of fusion science and related science andengineering through advancing simulation methods and basis technology• Application of the Numerical Simulation Reactor to design of high-performancehelical fusion reactor under inter-project collaboration
The NSRP Contributes to the NIFS future plan through application of simulation codesdeveloped in NSRP to physics & engineering studies of optimized configuration for the
Next Generation System (NGS) under inter-project collaboration• Turbulence & zonal flow modeling based on GK simulation to optimize equilibrium forreducing turbulent transport• Comparative study of modular-coils & helical-winding coils type optimizations• Investigation of flexible divertor structures
196/196References

Table of Evaluation Results for the 2019 External Peer Review

Table of Evaluation Results for the 2019 External Peer Review"Numerical Simulation Reactor Research Project"
Ⅰ. Points for Evaluation
１. Development of research plan, system, and environment（１）Does the Numerical Simulation Reactor Research Project (NSRP) appropriately set the goal and plan including theroadmap for construction of the Numerical Simulation Reactor? Are they properly discussed for accomplishing the third
midterm target and plan?
（２）Does the research system function appropriately in accomplishing the objectives of the NSRP with attention to the
management of step-by-step progress, research collaboration, and integration?
（３）Is the environment of the “Plasma Simulator” system and its related research appropriately developed and effectively
utilized accordingly to the research plan? Is the installation of a higher performance supercomputer properly planned?
２. Research achievements
Does the NSRP produce high-level achievements in accordance with international standards for the following researchareas described in the third midterm goal and plan by promoting theory and computer simulation research utilizing the
Plasma Simulator?
（１）Construction of the Numerical Simulation Reactor, Validation and improvement of simulation codes throughcomparison to experimental results（２）Academic systematization of fusion science and related science and engineering（３）Are research achievements steadily made according to the plan of the NSRP?
３. Promotion of cooperation and collaboration（１）Is collaboration research with universities based on theory and simulation research appropriately promoted? Does it
contribute to the progress of the NSRP?
（２）Does the NSRP contribute to enhancing functions of universities and institutes as the center of excellence for fusion
plasma simulation? Does the NSRP commit to the promotion of interdisciplinary collaboration and research?
（３）Does the NSRP contribute to international cooperation including ITER, BA activities, and others through international
collaboration activities?
４. Human resources development
Does the NSRP contribute to the development of human resources required for maintaining high-level simulation research
activities toward the future?
５. Future planIs the future research plan suitable for progressing toward the goal of the NSRP?
Does it also contribute to establishing the future plan of the National Institute for Fusion Science?

Ⅱ. Tabele of Evaluation
Number of persons
Point of Evaluation

Score

５
(Extremely highlycommmendable)

４(Highly commendable)

３(Commendable)

２(Adequate)１(Inadequate)

Average Score

１. Development of research
２. Research achievements
plan, system, and environment

３. Promotion of cooperationand collaboration

４. Human
resources ５. Future
developm
plan
ent

（１）

（２）

（３）

（１）

（２）

（３）

（１）

（２）

（３）

4

2

10

10

0

6

8

6

4

3

4

10

11

5

5

14

9

8

9

10

10

7

2

3

1

1

1

1

0

0

2

2

4

0

0

0

0

1

0

0

1

0

1

1

0

0

0

0

0

0

0

0

0

0

0

4.13

3.94

4.56

4.56

3.81

4.31

4.50

4.25

4.13

3.94

3.88

※The evaluation result is a combination of the results of domestic committee members (12 persons)and foreign committee members (4 persons).

Average Score

5.00
4.75
4.50
4.25
4.00
3.75
3.50
3.25
3.00
2.75
2.50
2.25
2.00
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0.00

4.13

1(1)

4.56 4.56
3.94

1(2)

4.31

4.50

3.81

1(3)

2(1)

2(2)

2(3)

3(1)

Point of Evaluation

4.25 4.13

3(2)

3(3)

3.94 3.88

45

Inter-University Research Institute Corporation
National Institutes of Natural Sciences

National Institute for Fusion Science322-6 Oroshi-cho, Toki, Gifu, 509-5292, Japan

http://www.nifs.ac.jp/