Using AMNS data within an Integrated Tokamak Modelling
Environment
Presented by: David Coster
(AMNS Coordinator, IMP3 Leader, Deputy Task Force Leader)
TF Leader : G. FalchettoDeputies: R. Coelho, D. P. Coster
EFDA CSU Contact Person: D. Kalupin
Using AMNS data within an Integrated Tokamak Modelling Environment2
Background
• The EFDA Task Force on Integrated
Tokamak Modelling
– coordinates the development of a coherent set of validated simulation tools
– benchmarks these tools on existing tokamakexperiments
– provides a comprehensive simulation package for ITER and DEMO plasmas
Using AMNS data within an Integrated Tokamak Modelling Environment3
ITM use of AMNS data
• AMNS data should be centralized and managed
– Version control of data imported to the ITM-TF
data base is mandatory.
– The provenance of the data must be accurate
and stored in the ITM database
– For “production” runs with ITM-TF codes using
AMNS data it is important that the data have
been given a stamp of approval by an expert.
Using AMNS data within an Integrated Tokamak Modelling Environment4
ITM use of AMNS data
• The data should be comprehensive, ubiquitous and easily used
– This means identifying what data is needed
• not always easy!
– The AMNS data must be communicated to ITM-
TF codes via a standardised interface
• this should also ensure coherence between different ITM-TF codes needing the same type of data
– All AMNS data used by codes should be
available through the AMNS data interface
• no back doors
Using AMNS data within an Integrated Tokamak Modelling Environment5
Approach in the ITM
Atomic Data
Molecular Data
Nuclear Data
Surface Data
AMNS
Library
Physics
Code
Physics
Code
Physics
Code
Physics
Code
AMNS Database
• Data selection
• Data import
• Data storage
• Data
transport
• User interface
design
• Supporting
multiple
languages
Using AMNS data within an Integrated Tokamak Modelling Environment6
Data selection
• Driven by
– user codes’ requirements
• fully differential cross sections for all relevant processes and species
– don’t really want to resolve all excited states so some sort of effective cross-section might be useful
» “bundling”
– data availability
• imported all of the ADAS ADF11 rate coefficients
Using AMNS data within an Integrated Tokamak Modelling Environment7
Data storage
• Need to have a data storage mechanism that
– allows us to store all of the AMNS data that are
needed
– allows us to store all of the additional meta-data
associated with the AMNS data
– allows us to effectively and efficiently use the
data
Using AMNS data within an Integrated Tokamak Modelling Environment8
Data import
• Need to store the data from outside sources in the AMNS database
– external data
• is available in a wide variety of formats
• is not always of the same quality
– need to capture the meta-data about the
imported data
• source of the data
• import procedure
• quality estimate
Using AMNS data within an Integrated Tokamak Modelling Environment9
Data transport
• Need to make the AMNS data available to ITM codes that might be running in a distributed environment
– remote data access is supported by the ITM’s
UAL (Universal Access Layer) for CPOs
(Consistent Physical Objects)
– could also create local copies of the database
• which can pose a problem of data consistency
• also means that we want to limit the number of files
– SOLPS uses a subset from > 1400 files, > 180 MB
Using AMNS data within an Integrated Tokamak Modelling Environment10
Making data available
• Need to make the AMNS data available through a standardized interface
– allows the data storage mechanism to change
without affecting user codes
– (hopefully) ensures that the data are correctly
used in the ITM codes
– allows users’ codes access to newer versions
of the data when such data becomes available
without the user having to re-code the data
access routines
Using AMNS data within an Integrated Tokamak Modelling Environment11
Making data available, II
• Challenges:– within the ITM we have codes written in
• Fortran
• C
• C++
• Matlab
• Python
– many codes will also be used outside of the ITM environment and code developers are not that keen on having to support one version within the ITM and one for use outside of the ITM
Using AMNS data within an Integrated Tokamak Modelling Environment12
ITM approach
• AMNS task under the ITM leadership
• Developed a data format for data storage
– actively evolving as we learn more about what
data is needed and discover that it doesn’t fit
• Developed a data access paradigm
– implemented this paradigm in a data access
library in Fortran
– have C bindings for this library
– are working on a Python interface
Using AMNS data within an Integrated Tokamak Modelling Environment13
Details: data storage
• ITM uses CPOs (Consistent Physical Objects) to store data
– experimental data (from present tokamaks)
– simulation data
– machine descriptions
– AMNS data
• Each CPO is described by an XML Schema– automatic tools then provide data access routines in
Fortran, C++, Matlab, Python, Java
– automatic tools provide for the storage, retrieval and transport of CPO data
• backends are (currently) MDSplus and HDF5; with add-ons ASCII data is also supported
Using AMNS data within an Integrated Tokamak Modelling Environment14
AMNS CPO
• ITM CPOs are identified by– USERNAME / DEVICE / DATA_VERSION / SHOT_NUMBER / RUN_NUMBER
• For the AMNS system we have chosen to use– USERNAME is the actual user, or if the user has no data, then
“amnsdata”
– DEVICE is “amns”
– DATA_VERSION is managed centrally and is changed when a new version of the CPO data structure is released (currently “4.10a”)
– SHOT_NUMBER is derived from the heaviest species involved in a process and equals ZN + ZM*1000 (ZN is the nuclear charge, ZM is the number of nucleons if the reaction depends on the isotopenand 0 otherwise)
– RUN_NUMBER represents the AMNS version number of the data
• Doing things this way allows us to leverage the already existing ITM infrastructure and to benefit from future developments
Using AMNS data within an Integrated Tokamak Modelling Environment15
AMNS CPO
• Design concept is still evolving
• Want to support data provided as– table
• R(x1. x2, .., xn)
• linear interpolation at the moment (1d, 2d, 3d, …)
– for R or log(R)
– for xi or log(xi)
• data stored in the AMNS database
– formula• R(x1. x2, .., xn)
• hopefully the formula has the right asymptotic behaviour!
• index to a predefined function stored in the database, together with any coefficients
Using AMNS data within an Integrated Tokamak Modelling Environment16
AMNS CPO, II
Using AMNS data within an Integrated Tokamak Modelling Environment17
Implementation
Physics code
• Access to AMNS data only via
interface
– initialization (2)
– finalization (2)
– querying parameters (2)
– setting parameters (2)
– getting data (1)
• Separation between use of the
data and the implementation of
the data
• Code author doesn’t need to
become an expert in AMNS
• Ensures compatibility between
codes
AMNS implementation
• Only accessed by a set of
defined calls
• Implementation by AMNS
experts
• Different versions can be
supported
• Different implementations
possible
– Analytic formulae
– Table lookup
• “Old” versions should always be
recoverable (even if wrong)
• Should become easier to
implement “new” data
Using AMNS data within an Integrated Tokamak Modelling Environment18
An example• A prototype has been implemented
– As a F90 module using derived types
– Interface will handle error estimates in the AMNS data!
call ITM_AMNS_SETUP(amns)
query%string='version'
call ITM_AMNS_QUERY(amns,query,answer)
...
call ITM_AMNS_SETUP_TABLE(amns, lr_rx, species_lr, amns_lr)
query%string='source'
call ITM_AMNS_QUERY_TABLE(amns_lr,query,answer)
...
set%string='nowarn'
call ITM_AMNS_SET_TABLE(amns_lr,set)
...
call ITM_AMNS_RX(amns_lr,rate(:,:),ne(:,:),te(:,:))
...
call ITM_AMNS_FINISH_TABLE(amns_lr))
call ITM_AMNS_FINISH(amns)
Using AMNS data within an Integrated Tokamak Modelling Environment19
Some examples
• Electron impact ionization (ADAS ADF11 SCD)
Using AMNS data within an Integrated Tokamak Modelling Environment20
Some examples
• D-D fusion cross section (Bosch-Hale formula)
Using AMNS data within an Integrated Tokamak Modelling Environment21
Some examples
• Differential elastic cross section for W (at 90o) (Tokesi, preliminary data)
Using AMNS data within an Integrated Tokamak Modelling Environment22
Coronal example: W
Using AMNS data within an Integrated Tokamak Modelling Environment23
Coronal example: W radiation
• No guarantees about the correctness
of the data used, or for the program
that calculated these results
• It was done to demonstrate how the
ITM AMNS system is used.
Using AMNS data within an Integrated Tokamak Modelling Environment24
Documentation
• Entries in the ITM web site derived from the AMNS database.
Using AMNS data within an Integrated Tokamak Modelling Environment25
Documentation• A sample entry
Using AMNS data within an Integrated Tokamak Modelling Environment26
Some thoughts
• Data needs are still evolving• ITM has
– data consumers
» data needs, not always clearly formulated
– data providers
– data packagers
» format of the AMNS CPO
» data import
» AMNS access library
– � Not always properly synchronized
Using AMNS data within an Integrated Tokamak Modelling Environment27
Some thoughts
• Having an IAEA recommended data set will make the ITM-AMNS job of selecting data easier
• If the IAEA data is in a standard format, then importing the data will also be easier
• If the IAEA data set has the provenance information standardized, then this will also make it easier when importing the data
• Decisions on how to categorize and store the data in the IAEA database might affect the organization within the ITM
• The ITM is likely, though, to have requirements that the IAEA database doesn’t