Title: Usage perspectives of EGEE infrastructure and grid technologies for Nuclear Fusion and ITER
1Fusion activities in the GRID (na4-egeeII)
Francisco Castejón francisco.castejon_at_ciemat.es CI
EMAT As coordinator of NA4-Fusion
SW-Federation (CIEMAT, BIFI, UCM, INTA -Spain-),
Russian Federation (Kurchatov Institute
-Russia-), CEA (France), ENEA (Italy), Culham
(UK), Korea (KISTI)
2Outline
- Motivation Fusion on the GRID.
- Data storage and handling.
- Fusion Deployment and VO setup.
- Applications Computing in Plasma Physics.
- Future Applications in the grid.
- Final Remarks.
3Motivation
- Large Nuclear Fusion installations International
Cooperation among several Institutes. - Generate 1-10 GB/sec. Less than 30 of data
goes into processing. - Distributed data storage and handling needed.
- Massive Distributed Calculation A new way of
solving problems. (Physics Problems still without
solution). - Fusion community (Science and Technology) needs
new IT approaches to increase research
productivity.
4JET - Pulse
Supercomputers
5ITER Making decisions in real Time !!
- Data Acquisition
- and Storage (Grid, Supercomputers)
Data Analysis and Reduction Artificial
Intelligence, Neural Network, Pattern Recognition
Simulations Large codes in different platforms
(Grid, Supercomputers)
Decision for present/next shot
One half an hour shot every one and half an hour
Decisions in real time.
6ITER Partners
Distributed Participation. Data access. Remote
Control Rooms?
7DATA HANDLING
Storage Large data flux 104 sensors x 20-50
kHz sampling 1-10 GBy per second raw data x 0.5
h 3 TBy per shot in ITER every 1,5
h Supercomputing and Grid Computing --gt Data
Storage Scratch and permanent. Data Access
Sharing in Large Cooperative Experiments A
unified representation for experimental data
native storages that LCG-2/gLite CE middleware
could understand is needed. (get and put the data
files from and into the storage). Storage should
allow to do some basic processing neural
network, clustering
8Communications
Remote Participation tools Data Access Local
Visualization Video Conferences and Chats Remote
Control SECURITY ROBUSTNESS
9PARTNERS and Resources for VO
- SW Federation CIEMAT, BIFI, UCM, INTA (Spain)
- Kurchatov (Russia).
- Culham Laboratory- UKAEA (UK)
- KISTI (South Korea).
- ENEA (Italy).
- CEA (France).
Experience in using and developing Fusion
Applications. Experience in porting applications
and developing Grid Technologies. --gt Connection
with EELA (Some fusion partners Brazil, Mexico,
Argentina)
10VO Deployment
http//grid.bifi.unizar.es/egee/fusion-vo/ http//
www-fusion.ciemat.es/collaboration/egee/
- Present CIEMAT 27 KSpecInts BIFI 8
KSpecInts INTA 6 nodes
- Within less than 6 months
- JET 38 KSpecInts BIFI 32 KSpecInts
CEA-Cadarache ? - KISTI?, INTA?, ENEA?
- Beginning of 2007
- JET 32 adtional cores BIFI 32 additional
cores CIEMAT ? - CEA-Cadarache ?(second phase already committed).
- project-eu-egee-na4-fusion-applications_at_cern.ch
11COMPUTING in the GRID Present Applications
- Applications with distributed calculations Monte
Carlo, Separate estimates, - Multiple Ray Tracing e. g. TRUBA.
- Stellarator Optimization VMEC
- Transport and Kinetic Theory Monte Carlo Codes.
12Multiple Ray Tracing TRUBA
Beam Simulation Bunch of rays with beam waist
far from the critical layer (100-200
rays) Bunch of rays with beam waist close to
the critical layer (100-200 rays) x (100-200 wave
numbers) 105 GRID PROBLEM
Single Ray (1 PE) Hamiltonian Ray Tracing
Equations.
13TRUBA Multiple Ray Tracing
Different results with the two approximations.
(Also useful tool for looking for Optimum
Launching Position in complex devices)
TRUBA for EBW Collaboration between IOFAN and
CIEMAT. Useful for all Institutes with EBW
heating (Culham, Princeton, Greifswald, CIEMAT,)
14TRUBA Multiple Ray Tracing
- TRUBA for EBW
- Cylinder geometry A single Non-relativistic ray
(tens of sec.) - Real geometry in TJ-IIComing from a
supercomputer (VMEC). - A single Non-relativistic ray (about 18).
- A single relativistic ray (about 40).
- Some problems with Geometry libraries.
- See
- J. L. Vázquez-Poleti. Massive Ray Tracing in
Fusion Plasmas on EGEE. User Forum, 2006.
15Stellarator Optimization Choosing the best
concept
LHD R 3.75 m a 0.65 m, M10, l2.
TJ-II R 1.5 m a 0.2 m, M4, l1.
HSX R1.2 m a0.15 m
CHS R 1 m a 0.2 m M8 l2.
16Optimised Stellarators QPS and NCSX Supercomputer
Optimization
NCSX
QPS
17The importance of Stellarator optimization.
- Design of new Plasma Physics-Fusion devices under
complex exigencies. OPTIMIZATION NECESITY BASED
ON KNOWLEDGE OF STELLARATOR PHYSICS.Many Labs
looking for the optimized device.
18Stellarator optimization in the Grid
Coils producing field confining the plasma may be
optimised numerically by variation of the field
parameters.
- A lot of different Magnetic Configurations
operating nowadays. OPTIMIZATION NECESITY BASED
ON KNOWLEDGE OF STELLARATOR PHYSICS.Every
variant computed on a separate processor (10)
VMEC (Variational Momentum Equilibrium
Code)120 Fourier parameters are varied.
19Neoclassical Transport.- Bootstrap current.-
Equilibrium vs. plasma pressure.- Stability
(Balloning, Mercier,)
Optimization Criteria Target Functions
Partícle trajectories in W7-X
- Genetic Algorithm to detect the optimum
configuration for given criteria. Target
Functions can be modified.
20VMEC on Kurchatov GRID
- LCG-2 - based Russian Data Intensive Grid
consortium resources. - About 7.500 cases computed (about 1.500 was not
VMEC-computable, i.e. no equilibrium). - Each case took about 20 minutes.
- Up to 70 simultaneous jobs running on the grid.
- See
- V. Voznesensky. Genetic Stellarator
Optimisations in Grid. User Forum, 2006.
21Kinetic Transport
- Following independent particle orbits
- Montecarlo techniques Particles distributed
according to experimental density and ion
temperature profiles (Maxwellian distribution
function) - SUITABLE PROBLEM FOR CLUSTER AND GRID TECHNOLOGIES
22Kinetic Transport
Example of orbit in the real 3D TJ-II Geometry
(single PE). 1 GBy data, 24 h x 512
PE Distribution function of parallel velocity at
a given position (Data Analysis).
23Kinetic transport
No collisions 0.5 ms of trajectory takes 1 sec.
CPU.. Collisions 1 ms of trajectory takes 4 sec
CPU. Particle life 150 - 200 ms. Single
particle 10 min. Necessary statistics for
TJ-II 107 particles.
24Kinetic transport The application
- Read from disk
- Input file (input.lis)
- Number of files.
- Number of trajectories in each file (may be
divided in blocks inside the file). - (total statistics number of files x number of
trajectories per file) - Length of each trajectory.
- Integration algorithm and time discretization.
- Number of measures in time.
- Temperature of backgroud electrons and ions.
- Random seed.
- Initial distribution (in space and velocity
space). - Model used, including or not
- Collisions with backgroud ions.
- Electric field.
- T-density dependence.
- Starting point according to a (space)
distribution function (perfil_densidad.in).
25- Written on disk
- Raw data ( OUT????.DAT)
- Pictures of the plasma at fixed times
(persistence, total energy, kinetic energy,
components of the velocity ...) - Points of escape of the particle from the TJ-II
(according to several different criteria) - 0.9 KB / traj. (typically 1000 traj. / file
-gt 900 KB) - writen every 1 hour
-
- Histograms (OUT????.HIS)
- Runtime histograms of serveral magnitudes
(energies, componentes of velocity, fluxes ...)
as a function of spacial coordinates (rho, phi,
theta) - 0.16 KB / traj. (typically 1000 traj. / file
-gt 160 KB) - writen every 1 hour
- Debug (RUNTIME.DAT)
- Measurements at the end of the trajectories, just
for check - 0.2 KB / file OUT???.DAT
- updated with every new OUT???.DAT (typically
1000 files -gt 200 KB)
26COMPUTING in the GRID Future applications
- EDGE2D Application for tokamaks
- Transport Analysis of multiple shots (typically
104 shots) or Predictive Transport with multiple
models e. g. ASTRA. CIEMAT(Spa) IPP(Ger)
Kurchatov(Rus) EFDA(UE) - Neutral Particle Dynamics EIRENE
- CIEMAT(Spa) IPP(Ger)
27JET Flagship of Worldwide Fusion EDGE2D
Equilibrium code.
28EDGE2D Determine plasma shape from Measurements
Plasma current, Pressure, Magnetic field
- EDGE2D code solves the 2 D fluid equations for
the conservation of energy, momentum and
particles in the plasma edge region. - Ions, electrons and all ionisation stages of
multiple species are considered. - Interaction with the vessel walls is simulated by
coupling to monte-carlo codes, to provide the
neutral ion and impurity sources.
29Massive Transport Calculations
For Instance Enhanced heat Confinement in TJ-II.
Lower heat diffusivity for low electron density
and high absorbed power density. A different
case on every PE.
30EIRENE Code
Trayectory of a He atom in TJ-II. Vertical and
horizontal proyections. It starts in the green
point and is absorbed in the plasma by an
ionization process. The real 3D geometry of
TJ-II vacuum chamber is considerd.
31EIRENE Code
Radial profile of atoms of He in TJ-II plasmas.
An average on every magnetic surface has been done
Radial profile of atoms of H in TJ-II
Two parts 1) Following trajectories (Totally
distributed) --gt GRID 2) Reduction to put all
together. EIRENE Code comes from IPP (Jülich,
Germany) and is extensively used by Fusion
community.
32Final Remarks
- GRID technologies will enhance Fusion Research
computing and data handling. - GRID technologies will win visibility when
applied to large Fusion Experiments (like ITER). - Demonstration effect If Fusion-Grid is
succesful, GRID technologies will be extensively
used by Fusion Community in the future. - FIRST APPLICATIONS ARE RUNNING IN THE GRID.
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