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3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 1
ITER Integrated Modelling– Status & Plans
W.A. Houlberg
ITER Organization
3rd ITPA Transport & Confinement Meeting
Princeton, NJ
5-7 October 2009
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 2
Outline
The ITER IM Programme:– Scope– Initial and boundary conditions– Predictive and interpretive analyses
Coordination between IO and Domestic Programmes
Status and plans:– Documentation– Website development– Computing cluster– Databases– Plasma control
Summary
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 3
Scope of the ITER IM Programme
ITER IM is responsible for all of the physics models and codes used in ITER predictive and interpretive analyses
ITER, as a nuclear facility, will require a well-documented core of physics codes to be applied systematically to every discharge:
– Predictive: analysis of control requirements and operation within bounds of ITER system capabilities
– Analysis: processing diagnostic data into temporally and spatially resolved physics parameters for real-time display and subsequent detailed analyses
– These core physics codes are expected to be based on reduced models for efficient application
– The core physics codes must be available to all users (with appropriate training)
The core codes will be backed by more comprehensive physics codes:– This is where the more extensive suite of codes and resources in the Domestic
programmes play a dominant role– These more comprehensive codes will link to the ITER experimental and
systems description data through the same set of interfaces as the core codes
A modular/component structure is required to satisfy these needs
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 4
Initial and Boundary Conditions
The seeds for the ITER IM Programme were sown by plans and discussions in the Domestic Programmes
The ITER IM Programme is ambitious:– It is broad in scope– It entails physics objectives beyond what we are presently capable of describing
with present theories or models, or have yet explored in experiments– It is designed to match the ambitions of the ITER Project– It can only be accomplished through strong collaboration between the IO and
Domestic Programmes
The expectation is that Integrated Modelling will continue to mature over the ~30-year life of ITER:
– The ultimate Integrated Modelling capabilities are not limited by present physics knowledge or tools
– Theories, models, experimental observations and computing capabilities all will improve
– We must build a framework to accommodate these improvements
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 5
Predictive Analyses
Supporting the design basis and its evolution:– Plasma magnetic control, H&CD and fuelling systems– Evaluation of upgrade options
Scenario studies:– Scoping with reduced models, backed by comprehensive calculations– Heating, fuelling and CD strategies
Campaign development:– Stability, control and diagnostic requirements, alternatives based on subsystem
availability, system limitations, fault amelioration techniques, sensitivity of operation to uncertainties
Plasma control:– Control strategies: plasma response times, sensitivity of plasma to actuators,
impact of events– Input to control algorithms: gains and response times with idealized sensors– Testing control algorithms: simulate plasma behaviour using control algorithms
with synthetic diagnostics linked to actuators– Physics components for control: provide CODAC with robust, well-validated real-
time physics models (e.g. equilibrium reconstruction)
Expect all of these applications to include extensive input from the community, e.g. scenario studies by the ITPA IOS TG
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 6
Interpretive Analyses
Real-time analysis:– Display of physics parameters using fast conversion of diagnostic signals
• Systematic employment of in-house suite of validated tools• Simultaneous display of modelled results in control rooms (local and remote)
Post-processing:– More rigorous conversion of diagnostic signals emphasizing consistency in
analysis, uncertainties (error bars), …• Systematic employment of in-house suite of validated tools for inter-shot and
overnight processing
Model validation and improvement:– More detailed, long-term analyses of selected cases
• Relies heavily on more extensive modelling capabilities within the ITER Parties
Physics codes for real-time and post-processing are to be based on tools used in present experimental programme:
– Joint effort between IM, Diagnostics and developers of ITER diagnostics
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 7
ITPA and IMEG Roles
ITPA – emphasis on R&D activities:– Databases to describe plasma characteristics over a wide range of conditions,
with particular emphasis on areas where theory and models provide inadequate coverage
– Model development and validation against experimental observations– Projections to ITER operation using a combination of experimental observations
and validated models
IMEG – emphasis on IM infrastructure:– Identification of a required core suite of in-house codes and tools for systematic
prediction and analysis of every discharge and available to all ITER MembersRely on adaptation of existing codes and toolsCore suite must be computationally efficient and well validated
– Establishment of standards and guidelines for the core suite (documentation, verification, validation, modularity, maintenance, …)
Required for coordination and integration– Identification and implementation of means to link to more in-depth analysis of
selected cases using codes available within the ITER Members IM ProgrammesFor example, more advanced physics models requiring high performance
computing, new approaches to coupling physics– Definition and development of the internal and remote user environment
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 8
Integrated Modelling Expert Group (IMEG)
IMEG responsibility is to assist the IO in defining and developing the ITER IM Programme, based on the experiences and capabilities in their Domestic IM Programmes
IMEG Members (coordinator)CN Li, J. Dong, J. Zhu, S.JA Mori, M. Fukuyama, A. Ozeki, T. (Deputy Chair)KO Jhang, H. Yoon, S.W.EU Thomas, P. McDonald, D. Strand, P. (Chair)RF Konovalov, S. Medvedev, S.IN Bandyopadhyay, I. Bisai, N. Srinivasan, R.US Van Dam, J. Batchelor, D. Lao, L.
1st IMEG meeting held 23-26 June 2009:– Reviewed ITER IM Programme objectives and approach– Surveyed related modelling efforts in ITER Parties– Reviewed initial draft of ITER IM Standards & Guidelines, and plans for
additional documentsGeneral consensus – very fruitful initial dialog, we all have a lot of work to do
and it must be well coordinated
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 9
ITER IM Documentation
IM ProgrammeIM Programme
Procedures & Conditions for
Accepting External
Simulations
Procedures & Conditions for
Accepting External
Simulations
Procedures & Conditions for
Accepting Elements into
IMAS
Procedures & Conditions for
Accepting Elements into
IMAS
Standards & Guidelines
Standards & Guidelines
Computer Hardware, Software &
User Access
Computer Hardware, Software &
User Access
ImplementationImplementation
User GuideUser Guide
ScientificScientific
Interpretive Analysis
Tools
Interpretive Analysis
Tools
DatabasesDatabasesPredictive Analysis
Tools
Predictive Analysis
Tools
Near completion
Started
Initiate
Explore options
IMAS - Integrated Modelling Analysis Suite
- In-house codes available to all parties
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 10
Websites Under Development
Sharepoint websites for FST Department, each section, ITPA taking shape:– Links to FST-related items in IDM make it much easier to find information
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 11
Migration of ITPA Website from IPP-Garching to ITER
ITPA website(s) – site with general information, separate sites for CC & TGs– In Sharepoint (ITER’s standard web tool)– Public information available through ITER Public website– Private information through ITER Technical website (require ITER account)
Expected features:– Uniform system for contacting various groups by e-mail– Links to ITER Research Needs and other communication between ITER and the
ITPA– Links to external private TG working sites if necessary (e.g. DBs)– Document management, publications, meeting info
Responsibilities:– Technical information: ITER Deputy Chairs, CC secretary will have primary
responsibility, supported by other volunteers designated by the ITPA– Design, development and overall management: Masanari Hosakawa
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 12
ITPA Public Website (not yet published)
Future meetings, links to local websites
Click on box to enter Private Site
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 13
IM Elements and Integration with ITER Systems
Predictive Analysis
ITERFacility
Diagnostic signals
Simulated diagnostic
signals
Simulated plasma data
Processed plasma data
Engineering data
Validation of synthetic
diagnostics
Synthetic diagnostics
Model validation
Data interpretatio
n
Control algorithm
s
Control Loop
Simulation
Interpretive Analysis
DatabaseIM elements
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 14
ITER IM Database Plans
Example of using tools developed by ITPA and the community: – Install MDSplus– Import copy of ITPA Profile Database (PDB08) and tools from Culham to use aa
a template for initial construction of an ITER DB:• Tree structure for scalar and profile data from many experiments and some
reference ITER cases: C. Roach et al, Nucl. Fusion 48 (2008) 125001• Tree structure for MHD equilibrium, SOL and divertor data developed by
ITPA Pedestal & Edge Physics TG added, but presently not used in PDB• Documentation http://tokamak-profiledb.ukaea.org.uk/DOCS/
– Unify tools for submission of ITER simulations, data checking, visualization
Assess extensions and unification for ITER reference cases:– Additional trees will need to be added, as well as other data structures to
describe the ITER configuration
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 15
Defining IM Role in Control Requirements
System requirements for control are being defined now
Plasma Control System (PCS) – FST responsibility (physics algorithms and models), but also:
– Part of a defense strategy but no direct responsibility for safety– Defense against disruptions, excessive machine conditions, …– Evaluates severity of conditions and may change operational sequence– Controlled termination if needed, or request CIS to intervene
Central Interlock System (CIS) – CODAC responsibility, primarily for investment protection:
– Failure or loss of PCS – takes control if thresholds exceeded– Emergency plasma termination – triggers mitigated disruption– Likely a long recovery time before next shot – ~hours
Central Safety System (CSS) – CODAC responsibility, primarily for personnel and nuclear safety:
– Triggers on failure of PCS and CIS or fault condition with safety implications– Shuts down operation (nuclear incident)
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 16
All Control Integrated within the CODAC Environment
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 17
Plasma Simulator in the Control System
A Plasma Simulator is envisioned as part of the control system:– Must be validated, robust and fast for discharge verification– Checks proposed discharge against machine capabilities – weeks in advance,
and again on day of operation:• H&CD and fuelling system availabilities• Operational boundaries• Diagnostic requirements• Control features
Capabilities needed:– Full plasma control (free-boundary equilibrium with transport) for discharge
design and verification– Efficient, validated physics models (including the core, pedestal, SOL, divertor)– Synthetic diagnostics for comparison with real-time measurements– Simultaneous display of expected performance form simulator along with data
from discharge evolution
Integrated Modelling responsibility to develop simulator:– Operation and maintenance responsibilities TBD
3rd ITPA T&C Meeting, 5-7 Oct 2009 - WAH Page 18
Summary
The ITER IM Programme describes an ambitious effort that designed to match the ambitions of the ITER Project
It can only be accomplished through strong collaboration between the IO and Domestic Programmes:
– ITPA for investigating the experimental and theoretical bases for physics issues of relevance to the ITER research programme, validating models, and providing assessments of the impact of these issues on ITER operation
– IMEG for establishing the infrastructure for integration of physics models across a variety of applications and origin of the computational models
The expectation is that IM (in both the ITER and Domestic Programmes) will continue to mature over the ~30-year life of ITER, and establish a solid basis for design and construction of DEMO
Near-term emphases:– Define needs, organization, development approach– DBs for facility description and simulation results– Websites for enhanced communication– Establish basic infrastructure and development schedule