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3rd meeting3rd meetingWorking Group 5Working Group 5

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Agenda WG5 2nd MeetingAgenda WG5 2nd Meeting

Agenda:

Discuss existing proposals

Indicate missing proposals

Allocate persons to develop proposals until July meeting

Overlap with other WGs

Dates / Miscellaneous

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Exiting ProposalsExiting Proposals

WG5.1 Reducing W sputtering by GD nitride formation (P. Tabares)

Needs further elaboration, closely connected to WG10.15,WG10.18

May be moved to WG10, Request for possibility of N GDC passed to operator

WG5.2 Monitoring of intrinsic impurity content (G. Maddison, H. Weisen et al.)

quite elaborated, using ‘monitoring’ discharges, partly parasitic,

WG5.3 Develop and Optimise Fuelling Techniques to Control/Avoid Tungsten

Accumulation (D. Frigione et al.)

some elaboration needed, could accommodate influence of seeding gas,

closely connected to WG5.6

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Exiting ProposalsExiting Proposals

WG5.4 Determination and control of the intrinsic impurity composition in the

full W divertor (S. Brezinsek)

Needs further elaboration, could accommodate influence of seeding gas,

closely connected to WG10.17 and WG10.20

WG5.5 Characterisation of evolution of C, Be and other light impurities

concentration (C. Giroud)

Mostly parasitic, may be merged into WG5.2

WG5.6 Characterisation and control of impurity production, transport and

contamination(C. Giroud)

some elaboration needed, use of trace injections, complements for tungsten

WG5.3 (concentrates on sources and edge transport, but for all intrinsic

impurities)

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Exiting ProposalsExiting Proposals

WG5.4 Determination and control of the intrinsic impurity composition in the

full W divertor (S. Brezinsek et al.)

Needs further elaboration, could accommodate influence of seeding gas,

closely connected to WG10.17 and WG10.20

WG5.5 Characterisation of evolution of C, Be and other light impurities

concentration (C. Giraud)

Mostly parasitic, may be merged into WG5.2

WG5.6 Characterisation and control of impurity production, transport and

contamination(C. Giraud)

some elaboration needed, use of trace injections, complements for tungsten

WG5.3 (concentrates on sources and edge transport, but for all intrinsic

impurities)

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• WG5.7 Study of central heating techniques to minimise/prevent Tungsten accumulation (D. Frigione et al.)

some elaboration needed, can partly performed jointly with WG 2.1 and WG 3.4

• WG5.8 W Divertor Retention (R. Dux et al.)

some elaboration needed, can partly performed jointly with WG 5.4, 5.6 and and WG10.17, 10.20

• WG5.9 Conditions for tungsten peaking and accumulation (H. Weisen et al.)

quite elaborated, prerequisite for WG5.3 and WG5.7

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Projection of ideas to proposalsProjection of ideas to proposals

• WG5.1x: 2.1,2.2 WG 5.2 (WG 5.5)

Behaviour of Be concentrations (in comparison to C with C wall), use reference discharges from pre ILW campaigns• WG5.2x: 2.3 WG 2.1, WG 5.6

Behaviour of Be influxes, concentrations in different RF heated scenarios (in comb. with WG5.5x)• WG5.3x: 3.1 WG 5.2

Monitor W influxes, concentrations in different discharge scenarios (mostly parasitic)• WG5.4x: 3.2 WG 5.8, WG 5.6

Role of ELMs for W concentrations• WG5.5x: 3.3 WG 5.8

W divertor retention, role horiz./vert. target (bulk/coating)• WG5.5x: 3.4 WG 5.9

Conditions for W peaking /accumulations• WG5.5x: 3.5 WG 2.1, WG 5.6

Behaviour of W influxes, concentrations in different RF heated scenarios (in comb. with WG5.2x),• WG5.6x: 3.5 WG 5.9, WG 5.7

Develop RF heated scenarios for W accumulation mitigation• WG5.7x: 3.6 WG 2.1, WG 5.6

Compatibility of W mitigation compatible with other ICRH application goals• WG5.8x: 4.1 WG 10.17, 10.20, WG5.8, WG 5.4 change of transport should be covered explicitly

Monitor intrinsic impurity influxes and concentrations in different impurity seeded discharge.

Perform specific discharges to disentangle source and transport effects• WG5.9x: 5.1 WG 5.6

Monitor intrinsic impurity influxes and concentrations for different ELM mitigation techniques. Perform specific discharges to disentangle source and transport effects

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Missing Items

Role of transport change in seeded scenarios (N/Ne/Ar)

Integration to find optimum with respect to impurity sources / transport and plasma performance

Close links to WG 14!

How do the tools extrapolate to ITER?

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Additional overlap with other WGsAdditional overlap with other WGs

WG 6.18 Comparison of plasmas with strong Be evaporation and Be first

wall with respect to impurity concentrations, content and fluxes

(S. Brezinsek)

WG10.15 W erosion amelioration due to nitride formation at the target plates

WG10.17 W and Be erosion due to extrinsic impurities injected into main

chamber and divertor

WG10.18 Study of BeN formation in the main chamber and divertor with

usage of N as seeding species

WG10.20 Be and W erosion in plasmas with combined seeding of N and

Ne/Ar - synergetic effects

Rest: see links on WG5 Wiki page

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Wishlist for elaboration of proposalsWishlist for elaboration of proposals

• Approximate number of sessions• Heating scenarios / power• Current / field• Shaping• Scarces resources

Define milestones for execution of proposals

Allow TFLs estimate for needed session

Allow TFLs draft of execution sequence

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MiscellaneousMiscellaneous

Dates for next meeting:

E1/E2 review meeting:

8/9 July How

28/07/2010 13:00 K1/0/38