E' Tsitrone, J' Roth, A' Loarte, J' Pamla

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E. Tsitrone, J. Roth, A. Loarte, J. Paméla
The EU-PWI Task ForceTask agreements for 2008

• EU PWI TF under new EFDA
• Task Agreements and preferential support for
  2008
• Whats next ?

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The EU-PWI Task Force under new EFDA
EU PWI TF remains a TF under new EFDA (access
to financial support ?TGs)
EU Task Force on Plasma-Wall Interaction Annual
Meeting of Contact Persons from 23
associations Defines priority issues ? Special
Expert Working Groups
Voluntary Physics Programme 3 year work programme
with 23 associations
Technological Programme 27 EFDA Tasks (art 5.1a
or 5.1b) for 2003-2006
Annual Task Agreements (general support)
Selected activities within TA eligible for
preferential support
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New tools under new EFDA Task agreements

• New managerial tool for SEWG leaders

• Clear set of objectives defined annually

• Work breakdown between associations (art 5)
• NB Includes JET activities agreed with JET EFDA
  leader, but under art 6

• Deliverables report by each association
  involved JET (SEWG meetings) final report by
  SEWG leader (PWI TF meeting)

• Financial support mostly general support
  (20 )? Selected activities preferential
  support ( 40 )

• No EFDA contract implementation through
  contract of association (CoA)
• No heavy administration, only Preferential
  Support to be approved at CCEFU.

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New tools under new EFDA Preferential support
and mobility

• Preferential support New for TF (0.5 ppy)
  and SEWG (0.25 ppy) leadershipAvailable for
  activities selected by SEWG leaders within TAs
  collaborative work (joint experiments,
  hardware exchange ) specific hardware
  (diagnostics ) high priority issues (Be, T )
  Detailed specifications( EFDA techno tasks)
  Milestones, deliverables, deadlines final
  written report by associations involvedCeiling
  for total amount of ppy/budgetFinal selection
  between associations proposals by EFDA TF
  leadership

• Mobility SEWG and TF meetingscollaborative
  work (joined experiments)

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10 Task Agreements for 2008
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Objectives and 2008 work programme SEWG Gas
Balance and Fuel Retention

• I Retention with non carbon ITER materials
• Carbon / ITER like wall (JET) complete database
  with carbon
• Carbon / full W (AUG) characterize retention in
  full W
• Be/ W / mixed materials (PSI devices)
• II Discrepancy between particle balance / post
  mortem analysis
• Extensive post mortem analysis of PFCs vs
  integrated particle balance
• ( assess uncertainties on both methods)
• Task agreement consolidation of post-mortem
  analysis with gas balance
• Preferential support coordinated post mortem
  analysis of tokamaks PFCs
• III Multi-machine scaling of retention
• Start with available data and run joint
  experiments to complete the database
• Compare the scaling obtained with modelling for
  identification of retention mechanisms.
• Task agreement multi machine scaling of fuel
  retention to ITER
• Preferential support joint experiments ? multi
  machine scaling of fuel retention

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Objectives and 2008 work programme SEWG
Fuel Removal

• I Advance chemical/photonic cleaning towards an
  ITER relevant system
• Improved removal rates with reduced collateral
  damage in situ in a tokamak
• Optimisation of flash-lamp (removal rate) and
  laser (co-deposit ? volatile)
• Quantify impact of metallic impurities in
  co-deposits on removal rates
• Preferential support coordinated surface
  analysis of treated samples (deposits
• remaining after cleaning and damage to bulk
  material)
• II Demonstrate removal of co-deposit in tile gaps
  with all technologies
• considered
• III Compatibility of Be with O cleaning methods
• Evaluate impact of repetitive oxidising plasmas
  (GDC/RF) on Be bulk
• Demonstrate Be/O removal rates (for
  post-oxidation recovery)
• Compare nitrogen/oxygen (effect on codeposition,
  removal rate, impact on Be)
• Task agreement treatment of metallic surfaces
  (Be) with oxidising plasmas for
• fuel removal
• Preferential support Compatibility of Be with
  O cleaning methods
• Impact of repetitive exposure of Be to oxidising
  plasmas
• Treatment of oxidised Be samples with glow or RF
  plasmas (He, Ar ) to establish cleaning rates
  and assess removed material.

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Objectives and 2008 work programme SEWG
Dust
I Characterization of dust in existing devices
(post mortem analysis) Sampling of dust in
different devices for analysis (size
distribution, shape, composition, specific
surface area) vs operating modes, maintenance
etc II. Initial assessment of dust generation
for ITER standard scenario with existing models
(not validated) III. Initial assessment of
diagnostics techniques a) During plasmas and
disruptions (visible, IR, CCD cameras, Rayleigh
scattering) Initial assessment for electrostatic
detectors and capacitive microbalance b) Between
plasmas (Mie scattering after gas injection) c)
Calibration for dust diagnostics assessment of
best technique to be selected (laser ablation,
pellets, mobile sieve, etc) d) Specifications for
proposal of a future diagnostic implementation
under preferential support Task agreements
joint measurements of dust in different
devices. Preferential support Coordinated
analysis of dust from different
devices Diagnostic exchange between devices for
joint characterization of dust during plasmas
(fast cameras)
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Objectives and 2008 work programme SEWG
Chemical erosion and transport (I)
Chemical Erosion
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Objectives and 2008 work programme SEWG
Chemical erosion and transport (II)
Transport
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Objectives and 2008 work programme SEWG
High Z materials
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Objectives and 2008 work programme SEWG ITER
like material mix
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Objectives and 2008 work programme SEWG
Transient heat loads and mitigation

• Determination of ELM and Disruption transient
  loads
• Optimisation of measurements of power/particle
  fluxes during mitigated and unmitigated ELMs and
  disruptions by interchange of diagnostics
  sharing of analysis techniques/software
• Determination of Type I ELM power/particle
  fluxes to PFCs in coordinated experiments
  (dimensionless pedestal identity and r/n scans)
  ? Model validation ITER extrapolation
• Determination of disruption power/particle
  fluxes to PFCs in coordinated experiments (Type
  I ELMy H-mode,VDEs, ITB collapse, etc.) ?
  identification of main physics processes and
  development of scaling laws models for
  extrapolation to ITER
• Mitigation of transient loads during ELMs and
  disruptions
• Develop common base for evaluation of mitigation
  effectiveness for
• disruptions thermal quench runaway
  suppression by MGI, current quench runaway
  suppression by ECRH ? initial assessment of
  feasibility/application to ITER
• ELM mitigation by pellets in comparable Type I
  ELMy H-modes ? initial assessment of
  feasibility/application to ITER

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Whats next ?
What already happened in 2007 STAC Feb 2007
highlights 2006 midterm work program STAC May
2007 TAs and preferential support for 2008
approved.? To be implemented when new EFDA in
force
Ceiling for preferential support for 2008 17
ppy and 300 kEuros

• Whats next ? Call to be launched soon
• Objectives
• confirmation of work offered by Associations in
  2006-2008 WP (through the draft TAs)
• additional contributions as needed
• opportunity for new Associations to join the
  programme
• preferential support (under precise
  specifications)

• To be sent to HRUs contact persons
• 10 drafts of TAs associations fill up proposals
  for participation associated resources

• 1 draft for all activities proposed for
  preferential support associations encouraged to
  send common detailed proposal (coordinated by
  SEWG leaders)

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Example of draft TA multi machine scaling of
fuel retention
Confirm (or suppress !) activity
Fill up associated resources
Propose new contribution
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Summary
The EU PWI TF remains a TF under new EFDAAdded
value of the TF recognized increased
collaborative framework (joined experiments,
common analysis, scientists exchange) focus on
ITER priority issuesNew tools task
agreements, preferential support,
mobilityImplementation started for 2008
transition year (phasing CoA and TF WP
) Questions (to Jerome ) welcome !