1. R. Neu: SEWG meeting, Oct. 1-2, 2009 1 The EU Plasma Wall Interaction Task Force : Work Programme 2010(-2011) R. Neu (Deputy TF leader, IPP Garching) E. Tsitrone (TF leader, CEA Cadarache) With contributions from : S. Brezinsek (FZJ), P. Coad (UKAEA), C. Grisolia (CEA), T. Loarer (CEA), K. Krieger (IPP), M. Lehnen (FZJ), G. Maddaluno (ENEA), V. Philipps (FZJ), J. Roth (IPP), M. Rubel (VR) EFDA contact: R. Zagorski (EFDA CSU Garching)

2. R. Neu: SEWG meeting, Oct. 1-2, 2009 2 Outline 1) Introduction: the PWI TF and the ITER context 3) Summary 2) Work programme 2010-2011 : proposals & major milestones

3. R. Neu: SEWG meeting, Oct. 1-2, 2009 3 Introduction : the EU PWI TF and ITER context

4. R. Neu: SEWG meeting, Oct. 1-2, 2009 4 ITER high priority research needs : strongly PWI related [D. Campbell, ITPA CC meeting June 2008] 1. Disruption/ Runaway Mitigation 2. ELM Control/ Mitigation 3. Plasma Facing Materials Physics basis for ITER reference scenarios with W/ Be PFCs ; C removal 4. Scenario Development 5. Diagnostics Dust / Hot dust ; divertor erosion ; mirrors ; H/D/T inventory Beryllium Tungsten Carbon Heat loads, runaway electrons: reduction > 1 order of magnitude Radiation cooling, supression of accumulation

5. R. Neu: SEWG meeting, Oct. 1-2, 2009 5 1. Disruption/ Runaway Mitigation 2. ELM Control/ Mitigation 3. Plasma Facing Materials Physics basis for ITER reference scenarios with W/ Be PFCs ; C removal 5. Diagnostics Dust / Hot dust ; divertor erosion ; mirrors ; H/D/T inventory Heat loads, runaway electrons: reduction > 1 order of magnitude Fuel retention Fuel Removal Transient heat loads ELMs and disruptions Material erosion and transport in tokamaks Materials Material migration High-Z Materials ITER-like Material Mix Dust in fusion devices Dust EU-PWI TF : targeted at ITER through 7 SEWGs Material ErosionW R&D Fuel retention Dust Heat loads ITPA Div SOL : 5 topics 4. Scenario Development Rad. cool., accumulation supr.

6. R. Neu: SEWG meeting, Oct. 1-2, 2009 6 Task Force Plasma-Wall Interaction Main orientations at Annual General Meeting Contact Persons from 23 associations + JET TF E and FT, EFDA, F4E, ITER IO Special Expert Working Groups Annual specialised meeting of SEWG members Joint meetings (High-Z & Transients for 2009) EU PWI TF: mature organisation Associations Baseline work programme : 20 % (?) Priority support : up to 40 % EFDA: ITM-TF TG MHD TG H&CD (ICWC) TG diags (LIBS) TG Mat (W alloys) TG Transp Emerging techno (Dust & T) (Disrup.) ITPA Div/SOL (co-chair) EFDA-JET: TF-E TF-FT (ILW)

7. R. Neu: SEWG meeting, Oct. 1-2, 2009 7 Highlights of 2008 Strong participation in PSI and IAEA 2008 > 20 oral papers (2 PSI review), > 100 publications ITER fuel retention ITPA DivSOL MIT meeting + IAEA + final report Joint meeting (ITM / MHD / PWI) on disruptions Preparation of WP2009 in new EFDA frame Call for interest launched in Summer 08 Task agreements finalised early 09 Annual meeting Frascati Oct. 2008 reporting : WP2008 95% executed (5% delayed)

8. R. Neu: SEWG meeting, Oct. 1-2, 2009 8 Definition of the Work Program for the next year(s) Presentation of the n+1 annual WP to EFDA SC (main lines – ceiling) (Feb-March) Call for Participation for n+1 WP (summer) Answer to call (early Sept) Call assessment by PWI TF (end Sept) Presentation to EFDA SC for approval (Oct) Task agreements drafted for n+1 WP (Nov) Implemented by end of the year SEWGs meetings Annual PWI TF meeting, reporting on current WP Timeline for the PWI TF preliminary evaluation of proposals Sep. 2009

9. R. Neu: SEWG meeting, Oct. 1-2, 2009 9 Work programme 2010-2011 : major milestones

10. R. Neu: SEWG meeting, Oct. 1-2, 2009 10 Main orientations for 2010-2011 Strengthening of modelling for extrapolation to ITER and DEMO – Interpretative modelling for benchmarking tools used for ITER simulations (SOLPS, ERO, DIVIMP …) – in close connection with ITM-TF (code development) 2 years WP : TA2010 and TA2011 will be very similar Integrated plasma operation : impact of impurity seeding – erosion, mixed material, fuel retention … Including recent ITER requests – disruptions/runaways – W R&D – divertor re-attachment heat loads – IC wall conditioning Bilateral collaborations : – mixed materials : PISCES (US) EFDA PWI TF (EFDA call for long term visiting scientist, deadline August 15!) – material damage : plasma guns (RF) F4E, but modelling + dust = PWI TF

11. R. Neu: SEWG meeting, Oct. 1-2, 2009 11 Materials SEWG Material migration Main wall erosion / redeposition Impact of impurity seeding on erosion Benchmark/development (gaps …) of local erosion/redep codes (ERO, …) SEWG High Z Impact of impurity seeding on W erosion Control of W contamination : erosion (ELMs, ICRH) core W + interpretative modelling of W erosion and transport Operation on damaged W PFCs + modelling of W damage & melt layer motion Liquid metals SEWG Material mixing Binary systems : comparison lab vs tokamak mixed deposits Impact of impurity seeding + thermal excursions (ELMs) on mixed material formation Extension of transport codes to simulate material mixing at the walls MD modelling of mixed material formation

12. R. Neu: SEWG meeting, Oct. 1-2, 2009 12 Fuel retention / removal / dust SEWG Fuel retention Multi machine scaling of fuel retention benchmark for ITER prediction methodology Post mortem : fuel location (gaps, bulk …) fuel removal SEWG Fuel removal Impact on dust production IC wall conditionning Removal in gaps SEWG Dust Dust conversion factor (gross erosion dust) Metallic dust Dust from maintenance, cleaning Dust from transients (Bilateral collaboration with RF on plasma guns F4E) Modelling of dust creation and transport Coordination TG Diag / EFDA Emerging techno needed : indication of (+ F4E / ITER IO) other calls!

13. R. Neu: SEWG meeting, Oct. 1-2, 2009 13 Transient heat loads Disruptions Particle and heat fluxes during disruptions (fast diags needed) –Asymmetries (convective + radiative fluxes) –Runaways : modelling needed –Heat loads in mitigated disruptions (MGI) Optimisation of disruption mitigation (MGI), including runaways suppression –Modelling needed for MGI impact (penetration, radiation …) Coordination MHD TG / ITM TF / F4E / ITER IO : joint meeting Feb 09 ELMs and inter ELMs heat loads Heat fluxes for unmitigated vs mitigated ELMs Main chamber : far SOL transport and fast particles Heat loads during loss of detachment events Material damage (Bilateral collaboration with RF on plasma guns F4E) Modelling of material damage & melt layer motion benchmark vs plasma guns + tokamaks SEWG Transients

14. R. Neu: SEWG meeting, Oct. 1-2, 2009 14 Total TA2009 : 22.6 ppy (+ 4 ppy for new associations) Total WP2010 : 23.75 ppy EFDA emerging techno + F4E High Z Disruptions Resources for 2010 : priority support

15. R. Neu: SEWG meeting, Oct. 1-2, 2009 15 Evaluation of Call and Preliminary Assignment TA1234567 PPY planned 321.53425.5 re- quested 5.14.972.478.3813.714.654.75 prelim. assigned 3.12.751.94.26.452.53.05 hardware planned 504050308030120 re- quested 3813040.5241264.2119.4130 prelim. assigned 302032901434570

16. R.Zagórski, SEWGs Meeting, Ljubljana, October, 2009 Reporting obligations are defined in the Task Agreement Baseline Support At the end of each calendar year, during the PWI TF annual meeting, the Task Coordinator shall present a report on all activities (baseline and priority support) under the Task Agreement to the EFDA Leader for his approval. These reports shall integrate the progress made by each Association on each activity, and they shall indicate the level of achievement of the objectives, the situation of the activities, the allocation of resources and recommendations for the next year when applicable. Priority Support Achievement of Priority Support deliverables will be reported separately to the EFDA Leader. A final report (and intermediate reports marking substantial progress in the achievement of deliverables, if the EFDA Leader so requests) shall be prepared by the Task Coordinator and submitted to the EFDA Leader. Each participation Association will have to report in one subsection on the degree to which the deliverables of their Task have been achieved, and shall include a breakdown of expenditure. The Task Coordinator will collect the individual subsections into the final report for Priority Support activities addressing the milestones. EU Task Force on Plasma-Wall Interaction

17. R.Zagórski, SEWGs Meeting, Ljubljana, October, 2009 Reporting on BS Scientific reports (deadline: PWI Annual meeting - 4-6 November 2009) Objectives: Synthetic description of the objectives and main milestones of the year Main Achievements: Description of the scientific outcome, highlighting the most important results. Report on the achievements against the objectives of the Task. Shortcomings Indicate which part of the work has not been done or delayed and why. Conclusions and General perspectives Indicate if and how the work should be continued, and which perspectives it could open inthe future. Publications: papers published/submitted, conferences, seminars, reports EU Task Force on Plasma-Wall Interaction Task id.Associations involved Manpower PPY Status*)Short description with milestones/deliverables WP09-PWI-05-03/IST/BSIST0.25DoneResults published in...... WP09-PWI-05- 03/SCK.CEN/BS SCK.CEN0.5Not doneExperimental time was not available *)Completed, Partially done, Not done Administrative reports: (deadline: 18 December 2009)

18. R.Zagórski, SEWGs Meeting, Ljubljana, October, 2009 Reporting on PS Scientific reports (deadline: 18 December 2009) Template ready to be sent to associations Task ID / association Achievements (0.5 page max) Brief description of the work carried out (experiments, hardware, code development, simulations, feasibility studies … ) Scientific outcome, highlighting the most important results and reporting on the achievement of the objectives. Mention of mobility trips, exchange of scientists, diagnostics, hardware … Shortcomings Indicate which part of the work has not been done or delayed and why, and whether it is to be postponed for the following year or cancelled. Publications / internal reports / presentations etc … List of related publications / internal reports / presentations etc … EU Task Force on Plasma-Wall Interaction

19. R.Zagórski, SEWGs Meeting, Ljubljana, October, 2009 Reporting on PS EU Task Force on Plasma-Wall Interaction Administrative reports: Association XXX Task id.Manpower Priority support Expenditure Hardware Expenditure Status*)Short description with milestones/deliverables References **) PPYkEuro PWI-08-TA- YY/XXX/PS/ZZ [1] *) Completed, Partially done, Not done (justification needed if task is not fully completed) **) Reference to the publications (listed below) has to be included here. In case no publication is available, indicate a reference to the scientific report sent by the association to the PWI TF (see part II for details). List of publications All reports to be sent to SEWG leaders SEWG leader compile report to be sent to TF leaders (deadline: 18/01/10)

20. R.Zagórski, SEWGs Meeting, Ljubljana, October, 2009Delays EU Task Force on Plasma-Wall Interaction Priority support tasks: Official request should be sent to EFDA Leader (cc EFDA RO) no later then 30 November 2009 - for tasks delayed more than 6 months) no later then 18 December 2009 - for tasks delayed less than 6 months) Baseline support tasks: Official request should be sent to EFDA Leader (cc EFDA RO) no later then 18 December 2009

21. R. Neu: SEWG meeting, Oct. 1-2, 2009 21 ITER : several top priority issues are PWI related (disruptions, ELMs, W R&D, diags for dust and T) EU PWI TF : reactive to ITER requests (ICWC, divertor reattachment) Summary Coordination : European (other EFDA TF/TGs, F4E) and international (bilateral collaboration with US, ITPA) 2010-2011 work programme established : Disruptions and high Z materials Modelling for extrapolation to ITER and DEMO Call July 2009 (new tool: ECOM, deadline September 5) Preliminary evaluation: PS strongly overbooked SEWG meetings : fuel retention/removal/dust : June15-17, Cadarache material migration / mixed materials : July 8-7, JET transient heat loads / High Z : October 1-2, Ljubljana PWI TF meeting : November 4-7, Warsaw PSI conference : abstracts due November 15 Deadlines for reporting: December 18

22. R. Neu: SEWG meeting, Oct. 1-2, 2009 22 Annex

23. R. Neu: SEWG meeting, Oct. 1-2, 2009 23 ITPA : new organisation ITPA (International Tokamak Physics Activity) has changed Summer 2008 : IEA (International Energy Association) legal framework of ITER Central coordinating committee : 3 representatives from each ITER partner Chair : R. Stambaugh (US), 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, US) New leadership for each group B. Lipschultz (chair), E. Tsitrone (co chair), R. Pitts (ITER co chair) selected Stronger connection to ITER organization : info + concerns both ways Coordinated experiments : DSOL (IEA on large tokamaks), international database

24. R. Neu: SEWG meeting, Oct. 1-2, 2009 24 1. Disruption/ Runaway Mitigation 2. ELM Control/ Mitigation 3. Plasma Facing Materials Physics basis for ITER reference scenarios with W/ Be PFCs ; C removal 5. Diagnostics Dust / Hot dust ; divertor erosion ; mirrors ; H/D/T inventory Heat loads, runaway electrons: reduction > 1 order of magnitude Fuel retention Fuel Removal Transient heat loads ELMs and disruptions Material erosion and transport in tokamaks Material migration High-Z Materials ITER-like Material Mix Dust in fusion devices Dust Towards increased coordination … F4E EFDA Emerging Techno Diag TG MHD TG, ITM TF H & CD TG US : PISCES RF : plasma guns

25. R. Neu: SEWG meeting, Oct. 1-2, 2009 25 SEWG Proposed Task Agreements for 2010-2011 SEWG Fuel retentionTA-1: Fuel retention analysis as a function of wall materials foreseen for ITER SEWG Fuel removalTA-2 : Exploration of fuel removal methods compatible with retention in mixed materials and metals (Be) SEWG Dust in Fusion Devices TA-3: Dust generation and characterization in different devices SEWG Material MigrationTA-4: Erosion, transport and deposition of low-Z wall materials SEWG High-Z Materials and Liquid metals TA-5: Development of the PWI basis in support of integrated high-Z scenarios for ITER and Demonstration of liquid PFCs SEWG ITER Material MixTA-6: Determination of expected alloys and compounds and their influence on PWI processes SEWG Transient Heat Loads TA-7: Mitigation of disruptions and ELM and inter-ELM heat loads WP2010: 7 Task Agreements proposed

26. R. Neu: SEWG meeting, Oct. 1-2, 2009 26 Manpower BS (ppy) Manpower PS (ppy) Hardware PS (k) Mobility (k) TF Coordination SEWG Coordination 1 1.75 TA-1: Fuel retention as a function of wall materials foreseen for ITER 7350 TA-2: Fuel removal compatible with retention in different and mixed first wall materials 1224050 TA-3: Dust generation and characterization in different devices 101.550 TA-4: Erosion, transport and deposition of first wall impurities 1733050 TA-5: Development of the PWI basis in support of integrated high-Z scenarios for ITER, Liquid plasma-facing components 2248050 TA-6: Expected alloys and compounds and their influence on PWI processes 923050 TA-7: Mitigation of disruption loads for ITER, ELM and inter-ELM heat loads 145.512050 Total91 ppy23.75 ppy400 k350 k Overview of resources requested for 2010 NB : resources requested for 2011 ~ same level

27. R. Neu: SEWG meeting, Oct. 1-2, 2009 27 Overview of 2011 resources Manpower BS (ppy) Manpower PS (ppy) Hardware PS (k) Mobility (k) TF Coordination SEWG Coordination 1 1.75 TA-1: Fuel retention as a function of wall materials foreseen for ITER 7350 TA-2: Fuel removal compatible with retention in different and mixed first wall materials 1224050 TA-3: Dust generation and characterization in different devices 101.550 TA-4: Erosion, transport and deposition of first wall impurities 1733050 TA-5: Development of the PWI basis in support of integrated high-Z scenarios for ITER Liquid plasma-facing components 2248050 TA-6: Expected alloys and compounds and their influence on PWI processes 923050 TA-7: Mitigation of disruption loads for ITER Heat load in ITER relevant ELM scenarios 14612050 Total91 ppy24.25 ppy400 k350 k

28. R. Neu: SEWG meeting, Oct. 1-2, 2009 28 Recent scientific achievements: Highlights of 2008

29. R. Neu: SEWG meeting, Oct. 1-2, 2009 29 SEWG Material migration Migration pattern refined, modelling progressing Erosion data in ITER relevant conditions (high particle flux / low energy) : Pilot-PSI interpretation ongoing (geometry, surface temperature) Tracer experiments ongoing ( 13 C) : AUG, Textor, TS Tracer injection + post mortem + modelling Main chamber inner divertor ok Outer inner divertor ? N 2 injection in lab experiments (PSI-2 …) N 2 scavenger effect confirmed. Tokamak ? [PSI08] Progress with the ERO code : Gaps, effect of ELMs, higher C x D y But : sticking probability, surface roughness, redeposited layers re- erosion [FZJ]

30. R. Neu: SEWG meeting, Oct. 1-2, 2009 30 SEWG High-Z Materials Radiation cooling with W walls, liquid limiters Progress in W diagnostics : IR, spectroscopy PWI basis for plasma operation with W walls (AUG) Successful operation w/o boronisation confirmed Boronisation radiation cooling essential reduced divertor heat loads Good performance in radiatively cooled plasmas (N 2 ) [PSI08, IAEA08] Effect of neutron irradiation : W specimen irradiated (0.25-0.75 dpa) Transient heat loads Cracks but no melting. Microstructure ? [SCK-CEN, FZJ] Liquid limiters : Li in FTU, TJII : LLL (performance increased) Ga in ISTOK [ENEA] [PSI08]

31. R. Neu: SEWG meeting, Oct. 1-2, 2009 31 Scaling of fuel co-deposition with Be, C and W : PISCES Multi factor : Tsurf, impact energy, arrival flux ratio revised modeling for T retention in ITER reduction (x 0.5) of predicted inventory due to temperature dependence SEWG ITER Material Mix: Ternary systems explored, scaling for fuel codep ITER Exploration of ternary systems : W-Be-C or Be-O-W Lab experiments but also tokamaks (W-C in Textor) 900 K 1120 K 1320 K He + ion fluence ~ 1–2×10 26 m -2 Detailed study of PWI with W : PISCES He & Be prevents blistering (300-700 K) He driven growth of nanostructures (10701320 K) suppressed with Be or C [PSI08] [PISCES]

32. R. Neu: SEWG meeting, Oct. 1-2, 2009 32 SEWG Fuel retention: Low fuel retention in full W AUG, gas balance vs post mortem Low fuel retention in full W AUG confirmed both from post mortem and gas balance C : codep in inner divertor W : implantation in outer divertor [IPP] [PSI08] Towards a reliable fuel retention assessment : better consistency post mortem / gas balance DITS project in Tore Supra Significant contribution from gaps in erosion zone [PSI08, IAEA08] Development of the LIBS technique (FZJ, CEA) : benchmarked against post mortem on Textor tiles Inner div Outer div Remote

33. R. Neu: SEWG meeting, Oct. 1-2, 2009 33 SEWG Fuel removal ICWC optimization, first trial on gaps Optimization of ICWC ongoing in Textor, Tore Supra, AUG Homogeneity of ICWC plasma (B field) Gas composition (He/D 2 ) [MedC] [CEA] Removal in gaps thermo-oxydation (CIEMAT), ECR or GDC (IPP, FZJ), laser (CEA), plasma torch (MedC) [PSI08, IAEA08] Dust production during cleaning processes : laser cleaning (IPPLM, VR) : dust/flake production with significant fuel content

34. R. Neu: SEWG meeting, Oct. 1-2, 2009 34 SEWG Dust Dust measurements during plasma, first dust injection experiments Dust measurements during plasma operation : CCD (TS, AUG), fast IR (AUG), electrostatic detector (TS), Thomson scattering (FTU) Dust collection ongoing : AUG, Textor, Tore Supra, FE200 Complex structure for C dust, spherical for W (droplets from transients ?) [PSI08] [FZJ] Preliminary dust injection experiments in Textor Driving force = j x B Edge C increased, no effect in core

35. R. Neu: SEWG meeting, Oct. 1-2, 2009 35 SEWG Transient heat loads Progress in fast diagnostics, mitigation with MGI [CRPP] Transient heat loads : progress in fast diagnostics (IR, bolometry) ELM filamentation, radiation during MGI Hardware exchange foreseen (fast IR) [PSI08, IAEA08] Material damage : collab RF plasma guns (F4E) + Judith (repetitive ELMs) [PSI08] Kinetic modelling of thermal loads in gaps : peak heat flux 2-3 x larger than tile surface (IPP.CR) Mitigation of transients : first experiments with RMPs on MAST dithering ELMs MGI (TS, AUG, TCV …) : Radiation not axisymmetric. Runaways ? Disruption avoidance with ECRH : ENEA, IPP [PSI08] [IAEA08]