Diapositive 1

1
International context ITPA (International
Tokamak Physics Activity)

• ITPA organisation
• ITPA DivSOL RD plan
• DSOL joint experiments
• Highlights last meeting / agenda next meeting
• Summary

B. Lipschultz, ITPA CC meeting, jul 2009
2
ITPA organisation
3
ITPA organisation

• ITPA ? legal framework of ITER since 2008
• ? Stronger connection to IO
• Central coordinating committee
• Chair R. Stambaugh (US)
• 3 representatives from each ITER partner
• EU J. Paméla, F. Romanelli, H. Zohm
• 7 ITPAs Transport and confinement (S. Kaye,
  US)
• Energetic particles (S. Guenter, EU)
• Integrated operation scenario (S. Ide, JA)
• MHD stability (A. Sen, IN)
• Pedestal (H. Wilson, EU)
• Diagnostics (R. Boivin, US)
• Divertor and SOL
• B. Lipschultz (chair), E. Tsitrone (co chair),
• R. Pitts (ITER co chair)

4
Divertor and SOL group The EU members

• 7 official members / ITER partner,
• EU nominated by associations, selected by EFDA

ITPA
Party
P. Tabares as stellarator representative

• EFDA rule mobility support for permanent
  members only (ceiling), additional experts
  supported by associations

5
DivSOL 5 task groups formed

• ITPA activities on a voluntary basis

• High priority research needs worked with the IO
  since early 2008
• 5 task groups formed ? DivSOL RD plan (May,
  2009)
• Tritium retention and removal (leaders - R.
  Doerner, J. Roth)
• Tungsten (leaders - A. Kallenbach, Y. Ueda)
• Dust (leaders - N. Ashikawa, D. Rudakov)
• Heat fluxes to plasma-facing surfaces (leaders -
  M. Lehnen, A. Leonard)
• Material migration (leaders - V. Philipps, P.
  Stangeby)

High Z
Dust
Transients
6
3 types of meetings

• 2 ITPA meetings / year (rotating between ITER
  partners)
• once a year joint meeting (pedestal,
  diagnostics )
• 2-3 months before meeting
• draft agenda circulated to the 5 topics leaders
  (last meeting list of topics)
• contributions collected (individual basis),
  topics selected (where enough contributions) and
  agenda consolidated
• 1 month before meeting final participation
  and agenda circulated to all
• during meeting list of topics (ITER needs)
  date/location for next meeting
• after meeting executive summary talks
  (available on ITER IDM)

• ITPA CC meeting mid july, ITER IO Cadarache
• Reporting of ITPA DivSOL activities

• DSOL joint experiments (IEA large tokamaks
  meeting)
• 15-16 december 2009, Daejon, Korea
• Reporting of DSOL experiments
• Discussion with heads of experimental programmes

7
ITPA DivSOL RD plan
8
T retention and removal compiled by R. Doerner
and J. Roth

• Refine ITER predictions (MIT mini-meeting) High
  priority
• Participants (JAEA, FZJ, UCSD, IPP, Kyushu,
  CEA, MIT, U. Toronto, Sandia, ITER, JET, FOM)
• Fuel retention machine database High priority
• Participants (FZJ, MIT, CEA, IPP, JET)
• Ion cyclotron wall cleaning High priority
• Participants (VR, FZJ, EAST, KSTAR, CEA, IPP,
  JET)
• Disruption flash heating High priority
• Participants (CEA, UCSD, UKAEA, ITER)
• Capability and risks of removing C Med.
  priority
• Participants (U. Toronto, VR, FZJ, CEA, IPP,
  JET, ITER, PPPL)
• Isotope exchange Med. priority
• Participants (JAEA, MIT, CEA, IPP, INL,
  Kyushu, FZJ, JET)
• T removal by heating to 350C High priority
• Participants (ITER, CEA, UCSD, IPP, INL,
  Sandia, UKAEA)
• Retention in gaps Med. priority
• Participants (FZJ, IPP, INL, UKAEA, Kyushu,
  JET, CEA, GA)
• Influence of mixed species on retention High
  priority
• Participant (UCSD, IPP, Kyushu, FZJ, JAEA, U ot
  Toronto, JET)

9
Tungsten RD compiled by Y. Ueda and A.
Kallenbach

• Impurity production by ICRH High priority
• Participants (AUG, CEA, C-Mod)
• Effect of divertor target damage on operation
  High priority
• Participants (AUG, C-Mod, JET, TEXTOR, QSPA
  TRINITI, QUEST)
• Tritium permeability and retention in
  neutron-damaged W High priority
• Participants (INL, IPP, Kyushu, Osaka, MIT,
  USCD)
• Investigation of surface morphology changes,
  blisters and material mixing High priority
  Participants (IPP-Garching, C-Mod, DIII-D, FOM,
  Kyushu, PISCES, NAGDIS, LHD, APSEDAS, TEXTOR,
  QSPA/TRINITI, Kurchatov, Bochvar)
• ELM impurity sources vs. flushing High priority
• Participants (AUG, DIII-D, FOM, JET, MAST)
• Power load control by low-Z seeding Med.
  priority
• Participants (AUG, C-Mod, DIII-D, JET)
• Edge modelling including W and Be/W Med.
  priority
• Participants (IO, FZJ, CNRS-UPR, IPP, JET,
  PISCES)
• Mixed impacting ions species and H retention
  Med. Priority see 1.9
• Participants (IPP, Bochvar, NAGDIS, PISCES,
  Toronto, Osaka)

10
Dust RD compiled by N. Ashikawa and D. Rudakov

• Characterization of dust production rates,
  conversion factor of erosion/damage to dust
  production High priority
• Participants (TEXTOR, AUG, TS, JT-60U, DIII-D,
  LHD, MAST, NSTX, FTU, EAST, JET, ITER)
• Dust characteristics under high loads ejection
  velocities, molten droplet size morphology/size
  distributions High priority
• Participants (TRINITI, QSPA, PISCES, ITER)
• Study the role of T removal techniques in dust
  creation Med. Priority
• Participants (U. Toronto, Pilot-PSI, NSTX,
  ITER, )
• Cross-machine studies of dust injection
  benchmarking of dust transport models High
  priority
• Participants (DIII-D, TEXTOR, LHD, MAST, NSTX,
  AUG)
• Dust measurements diagnostic development High
  priority
• Participants (NSTX, TEXTOR, DIII-D, FTU, LHD,
  UCSD, HT-7, AUG, MAST, JT-60U, CIEMAT)

11
Heat fluxes to plasma-facing surfaces compiled by
A. Leonard and M. Lehnen

• ELM characteristics High priority
• Participants (JET, AUG, DIII-D, MAST, C-Mod,
  JT-60U, NSTX)
• Disruption heat loads High priority
• Participants (AUG, C-Mod, JET, DIII-D, MAST)
• Transient detachment control High priority
• Participants (DIII-D, AUG. C-Mod, JET)
• SOL heat and particle fluxes Med. priority
• Participants (NSTX, C-Mod, DIII-D)
• Divertor and SOL ELM heat fluxes Med. priority
• Participants (DIII-D, JET, AUG, MAST)
• Modelling detachment Med. priority
• Participants (IPP/Garching, JET, JAEA, LLNL,
  IO, MAST)
• Rampup/rampdown heat loads High priority
• Participants (DIII-D, Tore Supra, JET)

12
Material migration compiled by P. Stangeby and
V. Philipps

• Cross machine comparisons of main wall erosion
  and local re- and co-deposition High priority
• Participants (Tore Supra, IO, EAST, AUG,
  TEXTOR, DIII-D, JET, JT-60U)
• Development of local models taking into account
  surface shaping and attempting to predict the
  observed deposition patterns for both steady
  (diverted operation) and limiter start-up/ramp
  down phases High priority
• Participants (UTIAS, IO, EAST)
• Characterise outer and inner divertor erosion as
  well as the movement of impurities from main
  chamber to divertor and from divertor to
  divertor Med. Priority
• Participants (AUG, JET, C-Mod, DIII-D, JT-60U)
• Material accumulation in tile gaps and its
  dependence on material, flux, temperature
  Med. Priority
• Participants (AUG, C-Mod, DIII-D, LHD,
  TEXTOR, JT-60U, JET)

13
ITPA joint DSOL experiments
14
DSOL experiments (9 running 2 new)
Fuel retention and removal DSOL-8 ICRF
Conditioning for hydrogen removal
(Ashikawa) DSOL-12 Reactive gas wall cleaning
(Stangeby) DSOL-13 Deuterium codeposition with
carbon in gaps of PFCs (Krieger) DSOL-16
Determination of the poloidal fueling profile
(Groth) ? will close Dust DSOL-21 Introduction
of pre-characterized dust for dust transport
studies (Rudakov) Transients DSOL-1 Scaling of
Type-1 ELM energy loss and pedestal gradients
through dimensionless variables (Loarte)
Closed DSOL-4 Disruption energy balance/heat flux
in similar discharges (Loarte) Closed DSOL-11
Disruption mitigation experiments (Whyte)
combined to MDC-1 DSOL-19 Impurity generation
mechanism transport during ELMs (Loarte)
Closed DSOL-20 Transient divertor reattachment
(Pitts) Material migration DSOL-2 Injection to
quantify chemical erosion (Brezinsek) DSOL-9
Tracer injection experiments to understand
material migration (Philipps) DSOL-17
Cross-machine Comparisons of Pulse-by-Pulse
Deposition (Skinner) ? will join material
migration
15
DSOL experiments (9 running 2 new)
Nothing on Tungsten yet Edge modelling DSOL-14
Multi-code, multi-machine edge modelling and code
benchmarking (Coster) ? Detachment modelling
(Wischmeier) DSOL-5 Role of Lyman absorption in
the divertor (Lisgo) Closed SOL transport and
turbulence DSOL-3 Scaling of radial transport
(Lipschultz) Closed DSOL-15 Inter-machine
comparison of blob characteristics (Terry)
16
Highlights last meeting / Agenda next meeting
17
ITPA last meeting highlights

• 12th meeting - Amsterdam, The Netherlands, May
  5-8, 2009, 50 participants
• ITER high priority RD plans ? 5 topics
• W for ITER (gaps), retention in W (He
  neutrons) low ! But surface morphology
• ICWC (more diags needed, large H consumption ?),
  fuel release after disruptions (more analysis
  needed for extrapolation to ITER, mitigated vs
  unmitigated)
• Divertor re-attachement (fast timescales,
  dedicated exp. needed) and detached divertor
  modelling (coordinated effort M. Wischmeier
  ITER IO)
• ? Slides / summary on ITER IDM

18
ITPA next meeting agenda

• 13th meeting San Diego, USA, December 14-17,
  2009
• Heat fluxes
• mitigated ELMs/disruptions
• secondary X point
• SOL widths
• H vs He
• Fuel removal 350C
• Dust injection modelling
• W damage (melting, cracking )
• Be erosion yield, 13C experiments review
• Status of RD plans
• ? Draft agenda circulated

• 14th meeting Asia ? fall 2010 ?

19
Summary

• Links with ITER strengthened (R. Pitts as new IO
  co-chair)
• Last meeting ITER requests on divertor
  re-attachement, fuel release after disruptions,
  ICWC
• Slides/summary on ITER IDM
• Next meeting San Diego, 14-17 December 2009 ?
  heat fluxes Agenda circulated
• New 5 topics RD plan consistent with PWI TF
  programme
• Tritium retention and removal (R. Doerner, J.
  Roth)
• Tungsten (A. Kallenbach, Y. Ueda)
• Dust (N. Ashikawa, D. Rudakov)
• Heat fluxes to plasma-facing surfaces (M.
  Lehnen, A. Leonard)
• Material migration (V. Philipps, P. Stangeby)
• ? Close contact needed ITPA topic leaders / PWI
  TF SEWG leaders

20
Annex
21
The Divertor and SOL group

• Up to 7 permanent members / partner IO
• 40 members
• (7 EU, 7 JA, 7 US, 6 CN, 4 KO, 3 IN, 3 RF, 3 IO)
• 1 contact person / partner

22
ITER high priority research needs Strongly PWI
related
1. Disruption/ Runaway Mitigation
Heat loads, runaway electrons reduction gt 1
order of magnitude
2. ELM Control/ Mitigation
3. Plasma Facing Materials
Physics basis for ITER reference scenarios with
W/ Be PFCs
4. Scenario Development
5. Diagnostics
Dust / Hot dust divertor erosion mirrors T
inventory
D. Campbell, CC meeting june 2008
23
Tentative DivSOL high priority research tasks
for 2008-2009

• Improve understanding of Tritium retention and
  development of efficient T removal methods.
• Compile high-Z experience regarding fuel
  retention in tokamaks and lab studies (new)
• Initiate studies on neutron damage and how that
  leads to T retention (new)
• Understand the effect of ELMs/disruptions on
  divertor and first wall
• Exploration of the effect on the SOL and power
  loadings of ELM mitigation (ongoing)
• Study runaway effects in disruptions and how to
  nullify them (new)
• Improve measurements understanding of plasma
  transport to targets and walls to better predict
  heat loads and effects on the core
• Code-code comparisons including impurities -
  specifically carbon (underway)
• Identify discrepancies between codes and
  experiment for SOL and divertor (new)
• High-Z operational experience (compatibility
  with core)
• Exposure of tungsten to He fluence and effects
  on surface properties (new)
• Characterize the level and processes involved in
  RF enhancement of erosion (new)

B. Lipschultz, ITPA meeting, sept 2008