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2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
The EFDA Programme
Duarte Borba
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
OUTLINE
• Introduction to EFDA• EFDA Programme
– Latest Results and Future Programme • JET• ITER Physics• Power Plant Physics and Technology (PPPT)
• Summary and Conclusions
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
OUTLINE
• Introduction to EFDA• EFDA Programme
– Latest Results and Future Programme • JET• ITER Physics• Power Plant Physics and Technology (PPPT)
• Summary and Conclusions
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
European Fusion Development Agreement (EFDA)
• Agreement between all EU fusion labs and Euratom
• Coordinated research (physics in support to ITER, longer term technology) and JET
• Garching (D) and Culham(UK)
Associations:European Fusion Laboratories associated to Euratom through “Contracts of Association”
The overall fusion programme is coordinated in the frame of EURATOM
Joint Undertaking for ITER “Fusion for Energy” (F4E)
• Domestic Agency to provide and manage EU contribution to ITER
• EU Contribution to Broader Approach
• Located in Spain (Barcelona)
Organization of EU programme
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
• Collective use of JET (~60M€/y operation + ~5M€/y exploitation + enhancements)
•Coordination of focussed physics and technology activities (~5M€/y priority support mobilizing ~25M€/y)
• Training (goal ~ 40 new trainee/y)
•EU contributions to international collaborations outside F4E
All EU Laboratories/Institutions working on Fusion are parties to EFDAEFDA
JET operated through a JET Operation Contract between the European Commission and the UK Atomic Energy Authority
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
EFDA Organization
EFDA Leader/Associate Leader for JET
F. Romanelli
Senior Advisor (Int. Collaborations) D. Borba
JETL. Horton
Public Information
P. Nieckchen
AdministrationC. Soltane
Power PlantPhysics &
Technology G. Federici
ITER Physics R. Neu
(From July 2012)
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
OUTLINE
• Introduction to EFDA• EFDA Programme
– Latest Results and Future Programme • JET• ITER Physics• Power Plant Physics and Technology (PPPT)
• Summary and Conclusions
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Carbon era of JET ended in 2009
8
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
9
Be/W ITER-like Wall completed
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
10
Bulk W
W-coated CFC
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Neutral Beam Enhancement Project
Beam voltage (kV)
Inje
cted
deu
trium
pow
er (M
W)
40 60 80 100 120 1400.0
0.5
1.0
1.5
2.0
2.5
Design goal: > 2.13 MW
EP1 PINIs
EP2 PINIs
PINI PerformanceNeutralisation efficiency measurements on Octant 8 beamline confirmed
that the design goal of >2.13 MW per PINI (>34 MW of total NBI power) can be achieved.
View through assembled duct in Assembly Hall, and installed in Torus
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Long Term Fuel Retention Predicted for ITER
10x
(4 months)
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Long Term Retention: rate normalised to divertor time
JET wall temperature
10x
JET-ILW: Is the absolute value low enough? True long term value could be much lower (surface analysis)
ITER
JET C-wall & ILW
10x
ICRHH-mode
Type III
NBIH-mode
Type I
L-mode
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Scenarios: Hybrid plasma
N~2.810%
n/nGreenwald~80%
Zeff~1.2
Central Te
Line integrated ne
Total radiated power
H98
JET-ILW: H98~1 also achieved in low and high shape inductive scenarios
H98 ~1 requires low fuelling but W control restricts operating window
Next: Higher power, ELM pacing and central heating (as AUG-W)
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
LH Threshold with ILWJET-ILW: Total power threshold JET-ILW: Separatrix power threshold
ILW shown unpredicted strong effect on pedestal and ELM behaviour
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
Launched Proposed
ConstructionITER
Phase 1
Construction
JET
JT60SA
Possible Scenario (2011-2018/20)
Ph3 DT
Operation
SD SD *SD Ph2
SD = Shut down
Ph2SD
* Exact duration to be quantified
Ph3 DTITER preparation with tritium plasmas
Start of Enhancement Projects RMP
Under further discussion
Interleaved deuterium, full tritium, trace tritium and high neutron yield DT Campaigns
Commissioning In Hydrogen
Two possible enhancements have been studied:Electron Cyclotron Heating System (ECRH)Resonant Magnetic Perturbation (RMP) coils
ITER preparation with all the control tools foreseen in ITER
Commissioning and Joint experiments
ECRH
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Plasma Stability and Control• Can large (~1MJ) ELMs be
suppressed ?
• Do n=4 and n=3 Resonant Magnetic Perturbations have the same effect ?
• Does a Be wall affect the ELM suppression ?
• Does the RMP affect the alpha particle confinement ?
Edge Perturbation Coils for Plasma Stability
Coils independently driven (in pairs)
at up to ± 60 kAt
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Possible JET DT experiment after 2015
• Test ITER operation regimes with tritiumabout 10 years before first ITER DT experiment.
T
D
10 MW NBI
pede
stal
pre
ssur
e (k
Pa)
Type III
Type I
• Isotope dependence of confinement• ITER relevant Ion Cyclotron heating techniques with tritium• Diagnostic techniques relevant for DT operation in ITER
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
OUTLINE
• Introduction to EFDA• EFDA Programme
– Latest Results and Future Programme • JET• ITER Physics• Power Plant Physics and Technology (PPPT)
• Summary and Conclusions
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
, ,
VI-1: Diagnostics, 500
Reserve, 1600
VI-3: Fusion Materials Development, 600
III-2: Transport, 300III-1: MHD, 200
III-3: H&CD and Fuelling Physics, 130
V-1: Integrated Tokamak Modelling,
700
IV: Coordinated Activities on Plasma Wall Interaction, 750
VII-1: SERF, 20
Elec
tric
pot
entia
lan
d Io
n st
ream
line
s
shadowed
open
~1m
m
0.5
mm
Elec
tric
pot
entia
lan
d Io
n st
ream
line
s
shadowed
open
~1m
m
0.5
mm
EFDA ITER Physics Programme
• EFDA/F4E Collaboration on JT60SA EU Physics Activities • High Performance Computing
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Modelling of RMP screening with plasma flows
First tests results on screening of RMPs by toroidal and diamagnetic flows were obtained for JET-like parameters (EFCC coils, n=2,96kAt),
Equilibrium radial electric field with diamagnetic 2 fluids effects in JOREK.
vacuum case
Islands screening by rotation
CEA
MHD
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
• Large Eddy Simulation tehcnique applied to gyrokinetics in GENE [Banon Navarro PRL 11, Morel PoP 11 & 12]
• Progress towards reliable multi-scale simulations at reduced numerical cost
ULB, IPP
[ Morel PoP 12 ]
Free energy injection spectra for the fourth-order model (M4) at reduced resolution, compared with a highly resolved DNS.
Multi-scale turbulence (modeling)Transport
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Multi-scale turbulence (experiment)
• TORE SUPRA: measurements of extended wave number spectra enable validation of models for multi-scale turbulence, and turbulence simulations
GENE
CEA
[ Vermare PoP & EPS 2011 ]
Transport
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Assumed SOL Density Profile
Modeling of scrape-off plasma with TOPICA and TOPLHA validation of the ITER and other IC and LH antenna design in plasma regimes with different scrape off layer density decay length. AUG antenna has been simulated in details.
Modelling of RF Sheath and power coupled to Plasma
ENEA
Modelled Power coupled to plasma
Heating and Current Drive
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
High-Z Materials Limiter with tungsten lamellae insert before exposure to TEXTOR plasma boundary
FZJ
Measured height profile along W surface after melting by excessive heat flux in TEXTOR discharge with computed height profile obtained by a MEMOS code simulation.
PWI Task Force
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
26
Anatomy of Modular codes
Legacy software structureITM Task Force
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
38th EPS 2011, June 27 – July 1, C. Konz
27
Standardized module interfaces:
• allow for simple construction of generic workflows
Access to database
Equilibrium chain Kepler Workflow
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
38th EPS 2011, June 27 – July 1, C. Konz
28
Standardized module interfaces:
• allow for simple construction of generic workflows
• easy interchange of modules from same type of physics
Equilibrium reconstruction: free boundary equilibrium module
Equilibrium chain Kepler Workflow
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
38th EPS 2011, June 27 – July 1, C. Konz
29
Standardized module interfaces:
• allow for simple construction of generic workflows
• easy interchange of modules from same type of physics
Equilibrium refinement: high resolution fixed boundary equilibrium module
Equilibrium chain Kepler Workflow
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
38th EPS 2011, June 27 – July 1, C. Konz
30
Generic visualization using Python scripts
Equilibrium chain Kepler Workflow
Standardized module interfaces:
• allow for simple construction of generic workflows
• allow for generic visualization of results, e.g. Python, VisIt
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Demonstrated Kepler workflow, using experimental/synthetic JET data, coupling the equilibrium code Helena and the gyrofluid turbulence code GEM. GEM is executed in batch on the HPC-FF
First-principle turbulence codesworkflow running on HPC
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Core-Edge Coupling
• Te in the Scrape-Off Layer computed by SOLPS
• Te in the core computed by ETS (coreprof edge)
• Visualized in the ASDEX Upgrade device geometry
• Raw geometry data provided by IPP Garching (T. Lunt),
• Postprocessing done at Aalto University, Helsinki (T. Kuoskela)
• Simulation and integrated visualization performed at IPP Garching (H.-J. Klingshirn),
• Using VisIt visualization software and general-purpose ITM tools
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Reflectometer plasma position controlReflectometer plasma position control was achieved both in L and type-I ELMy H–Mode phases.
The shaded regions show the discharge phases in which reflectometry separatrix estimate replaced the magnetics as the radial outer plasma position source for feedback control.
The solid black lines show the pre-programmed plasma position controller target trajectory. The green curves show the magnetic separatrix position and the red the reflectometry estimates for the outer separatrix position.
IPP, IST
Diagnostics and RT Control
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
EFDA/F4E Collaboration on JT60SA EU Physics Activities
• EU Research Unit Coordinator is Gerardo Giruzzi (CEA).• Joint EU-JP revision of the JT60-SA research plan
completed in 2011 with the issue of version 3.0. • Meeting to finalise the activities for 2012 will take place
in in Frascati, 4 – 5 June 2012.
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
EFDA/F4E Collaboration on JT60SA EU Physics Activities
2012 Work Programme focus on: -General subjects
- Follow-up of Research Plan revision,- Modelling of JT-60SA plasmas (performed by the ISM project ) - Definition of JT-60SA data system, validation and analysis tools- Experiments and data analyses on EU machines in support of JT-60SA
- Specific subjects - Evaluation/optimization of the ECRH launcher - Assessment of selected diagnostic systems - Assessment of JT-60SA divertor pumping system
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
High Performance Computing HPC-FF Julich, Germany
Comparison of the filamentation of the plasma during an ELM in the MAST tokamak
• Total of 68 projects awarded CPU time in 2011 and 60 projects in 2012
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Allocated CPU-hours
Turbulence
Materials
Edge
MHD
Nuclear
RF
Mix
Fast particles
High Performance Computing HPC-FF Julich, Germany
HPC-FF Usage since Production Started in August 2009
•HPC-FF now basically full (some idle time necessary to queue-in large CPU jobs)
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
High Performance Computing IFERC Computer (Helios), Rokkasho, Japan
• According the Terms of Reference of the Standing Committee governing the usage of the IFERC supercomputer in Rokkasho, 20% of the time will be allocated directly to the parties (10% for each of the EU and Japan) to enable them to do tests, tuning or adaptation of codes, etc. The parties will internally organise the use of this time, which is available since 9th April 2012.
• The remaining time 80% is allocated to projects.
• 58 Proposals were accepted and allocated 20.45 M Node Hours in the 1st Cycle of operation
• Deadline for proposals for the Second Cycle is end of July 2012.
http://www.iferc.org/csc/for-researchers/hpc-information.html
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
High Performance Computing IFERC Computer (Helios), Rokkasho, Japan
• After discussions with F4E it is agreed that the 10% of time for the EU will be allocated according such as each Associate receives
800 000 CPU core hours (50 000 node Hours), for use by fusion researchers in their country.
• The same contact persons, as used for the HPC-FF Association accounts, administer the Helios accounts.
For TEKES the contact person is Jukka Heikkinen (jukka.heikkinen@vtt.fi)
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
OUTLINE
• Introduction to EFDA• EFDA Programme
– Latest Results and Future Programme • JET• ITER Physics• Power Plant Physics and Technology (PPPT)
• Summary and Conclusions
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
System code Studies for optimisation of System code Studies for optimisation of Fusion power plant DEMO conceptsFusion power plant DEMO concepts
• For pulsed operation, the main aspects of concern at present are the flux swing, pulse length and divertor heat load modelling, although there are some concerns about cyclic fatigue issues, which are not well captured in systems studies at present.
• In modelling steady-state devices, the main concern at present is the divertor heat load and radiation modelling.
• These studies should lead to improved modelling but also to new experimental work to validate key assumptions such as the impact of radiation on confinement, plasma behaviour at high density and high β.
Conservative Advanced
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Assess Prospects for Alternative Assess Prospects for Alternative Concepts for Heat Removal in Fusion ReactorsConcepts for Heat Removal in Fusion Reactors
• Capillary porous systems (CPS)– Optimize heat extraction without evaporation cooling for Li systems in
magnetic confinement devices. – Test the resilience to transients loads (disruptions, ELMs)– Test other material options (e.g. Ga, Al, Sn)
• Droplet systems– Check stability of droplet systems in magnetic confiment devices and in
test stands with high magnetic fields
• Liquid metals, basic properties– Identify temperature window with low evaporation and low tritium retention
(mainly Li)– Understand T retention mechanism– Decide on reactor compatibility
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
High Temperature Super ConductorsHigh Temperature Super Conductors• REBCO (rare-earth barium-copper-oxide high-temperature
superconductors) is the only candidate for application for fusion magnets
• Demonstrators have shown currents up to 7.5 kA (77 K, self field)
• Operation at 4 K and fields in the range of 12 T - 18 T is possible and allows
• e.g. 74 kA @ 4 K and 15 Tesla • 30% volume reduction of winding pack• Effective current closer to the plasma -> higher field
• The higher cost for REBCO could be partially balanced by simpler structure (no radial plates), no SC annealing andsimpler HV insulation of the cable
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Remote HandlingRemote Handling• In-vessel gamma radiation dose levels of ~20kGy/hr after 2 fpy will
prohibit the operation of many remote handling technologies within the Tokamak
• The Vertical Maintenance System with Multi Module Segment (MMS) is considered to be the most viable plant architecture for power plant relevant maintenance
• Due to the harsh conditions predicted within the tokamak, ex-vessel remote operations need to be maximised to minimise those required in-vessel and planned in-vessel maintenance should not include any complex operations, i.e. cutting and welding.
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Material Programme in EFDAMaterial Programme in EFDA
The materials programme in EFDA is being reoriented along three main lines:(a)DEMO materials choices and specifications:
• DEMO 2030 will probably need to use “existing” materials (e.g. EUROFER)• Reconsider Cu-alloy for a water-cooled divertor.
(b)guidance of test matrixes for irradiation campaigns• design of material irradiation experiments to consolidate the materials
database for DEMO structural materials using existing fission reactors (e.g., by using isotopic tailoring) dual ion-beams, modelling of radiation effects, exploitation of post-EVEDA irradiation campaigns
(c)development of improved materials for later fusion devices• Tungsten and tungsten alloys• Oxide-dispersion-strengthened ferritic steels (ODSFS)• Material modelling.
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
SummaryJET • The ILW JET shutdown was completed • First results confirm low tritium retention• Operation with the ILW achieved more easily then expected• Good H-mode confinement discharges established
The ITER-like Wall has shownAnticipated benefits and risks of a W/Be wall:Large reduction in fuel retention and very clean/reproducible plasmasITER scenarios constrained by W-accumulation but still achievableGood power handling and protection of the Be/W wall
An unpredicted strong effect on pedestal and ELM behaviour
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Summary• ITER Physics EFDA programme covers a number of key physics priority questions for ITER exploitation:
• MHD, Transport, H&CD, PWI, ITM, Diagnostics
• Preparation of the operation of JT60-SA together with Japan• Management of Super Computer Resources (HCP-FF and Helios)
• Power Plant Physics and Technology (PPPT) activities:• System code Studies for optimisation of Fusion power plant DEMO concepts• Concepts for Heat Removal in Fusion Reactors • High Temperature Super Conductors for Fusion Applications• Remote Handling• Fusion Materials Research
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Thank you for attention
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Backup Slides
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
EFDA 2012 Work Programme Implemented under Cross Topical Areas of Research
1. Prediction of Material Migration and Mixed Material Formation (PWI, DIA)
2. Shaping and controlling performance limiting instabilities (MHD, DIA, H&CD-F)
3. Fuel Retention and Removal (PWI, DIA, H&CD-F) 4. Plasma rotation (MHD, TRA, H&CD-F)5. Core electron heat transport and multi-scale physics (TRA,DIA)6. Pedestal instabilities (ELMs), Mitigation and Heat loads (MHD,
TRA, PWI, DIA, H&CD-F) 7. Disruptions, prediction, avoidance, mitigation and consequences
(MHD, PWI, DIA) 8. Physics of the Pedestal and H-mode (DIA, TRA, H&CD-F) 9. Fast Particles (MHD, TRA, DIA, H&CD-F)10. Particle transport, fuelling and Inner Fuel Cycle modelling (TRA,
H&CD-F, PWI) 11. Operation with metallic plasma facing components, including High
Power ICRH (PWI, H&CD-F)
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
New CC Chairs for H&CD• Two new Chairs of H&CD Coordinating Committees have been appointed:
– J.M. Notraedame (IPP) for the Coordinating Committee Ion Cyclotron Heating, replacing R. Koch;
– A. Tuccillo (ENEA) for the Coordinating Committee Lower Hybrid, replacing T. Hoang
– and E. Surrey (CCFE) chair of the Coordinating Committee on Neutral Beam– C. Day (KIT) chair of the Coordinating Committee Fuel and Pumping
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Calibrated particle source(gas injection modules)
Gas collection on divertor cryo pumps
Fuel retention: long (co-deposition & implantation) +
short term (surface)
Repeat sets identical discharges
Injected gas = Pumped gas+ Short term retention + Long term retention
Regeneration of cryogenic pumps before and after experiment
1. Stronger gas consumption during limiter phase with ILW ≈ 2x2. Lower gas consumption during divertor phase w.r.t. CFC walls3. Stronger outgasing after the discharge compared to CFC walls
Note: C-wall long term retention from surface analysis << gas balance
Fuel retention: JET Gas Balance Experiments
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
High Frequency Pellet InjectionSmall pellets 1.5mm diameter
Large pellets (4mm diameter)
Highest velocities not achieved for highest injection frequencies (especially for large pellets)
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Commissioning with Plasma 2012• Ice quality ‘oscillates’ during extrusion. • Good pellets only during periods of good ice• Hard to synchronise pellets with plasma.
Nevertheless: Some successful experiments with large pellets:
Achieved in one shot increased ELM frequency 7 Hz to 20 Hz at averaged, up to 31 at maximum (short phase): Unwanted fuelling side effect gone for entire sequence!
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
55
9. ConclusionsThe ITER-like Wall has shownAnticipated benefits and risks of a W/Be wall:Large reduction in fuel retention and very clean/reproducible plasmasITER scenarios constrained by W-accumulation but still achievableGood power handling and protection of the Be/W wall
An unpredicted strong effect on pedestal and ELM behaviour
ITER/DEMO scenario development needs relevant PWIi.e. PWI issues and H-mode physics are not separable
Exploitation & analysis of the ITER-like Wall has only just begun
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Fuel retention
I II III
2.3μm
TEM image of cut through surface zone of W sample irradiated by 20 MeV W+ with damage sites visible to a depth of up to 2.3 mm (indicated by red arrow). Three zones can be separated: I – near surface area with high density of dislocations, II – intermediate area with lower density of “long” dislocations and “sub-grain” regions free from dislocations, III – deep region with high density of “short” dislocations.
• Apart from material structure, fuel retention in tungsten is also strongly influenced by radiation damage, increasing the number of trapping sites for fuel atoms in the material. • The type of damage sites created by this method was studied by cutting lamellas out of W-ion irradiated tungsten samples and TEM analysis of the lamellas.
IPP
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Fuel retention
ED+=20eV
0 1 2 3 4 510-3
10-2
10-1
100
D @ vacancies /vacancy clusters
D @ dislocations
damageprofile 630 K
500 K
damaged W exposed to 2.2×1025 D/m2
Dco
ncen
tratio
n /a
t.%
Depth / μm
IPP
Depth profiles of implanted deuterium in pre-damaged tungsten measured by nuclear reaction analysis for different sample temperatures during low-energy D-plasma exposure. With increasing temperature, D does not decorate dislocation sites anymore but is still trapped at vacancies created by previous radiation damage within the first 2 microns of the surface.
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
Transient heat loads CCFE
Fraction of stored plasma energy reaching divertor surface after mitigated disruptions D using Neon, Argon or He/Ar mix in MAST.
Compared to typical deposition of 80% of stored energy in the divertor following unmitigated disruptions, massive gas injection can reduce this fraction down to 40%.
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
• A dual probe technique comprising planar Langmuir probe and hairpin probe has been tested and calibrated with Laser photo detachment technique to estimate the negative ion density.
• The negative ion density in front of anodic glow is on the orders of 1011 cm-3 and increases monotonically with applied power.
NBI source development (negative ions plasma source)
Plasma Source
Spatial plasma parameters are measured from the edge of the anode glow, using a hair pin probe and emissive probe.
IPPHeating and Current Drive
2012 Annual Seminar of Association EURATOM-Tekes Estonia 29-30 May 2012
• Heat loads onto divertor of 10-15 MW/m2 require a heat sink material with high thermal conductivity: Only Cu-alloys can be considered
• In 2011 an initial assessment of data available on Cu-alloys was conducted (PEX/02 + DAS MAT).
• Lack of data for relevant irradiation doses. • Need to investigate also high-radiation resistance Cu-alloys
Water-cooled Divertor
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