EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

Status of ITER like wall project

V. Philipps

ITER

2 options are under preparation, decision about time schedule at a given time

EU-PWI-Task Force

TF Meeting, 17-19 2005 Cadarache

1

Physics research in associations

• Fusion devices

• linear plasmas

• lab experiments

etc..

2

EFDA PWI technology programme

• specific tasks

• integration of work outside

associations

3

Integrated wall experiments in fusion devices

Organisation & work structure

See Albertos talk

AUG

JET wall experiment

Main part of our meeting

JET with Be wall and all Tungsten divertor

Objectives

• Demonstrate low T retention

• Study effect of Be on W erosion

• Study ELMs and disruptions on wall & divertor, melt layer behaviour

• Develop control / mitigation techniques for ELMs and disruptions

• Test de-tritiation techniques

• Operate Tokamak without C - radiation

Demonstrate operation of ITER scenarios at high current and heating power with a Be/W material choice

EU PWI Task ForceJET ITER like Wall material experiment

EU PWI Task Force

Full Be wall with ITER like Carbon/tungsten divertor

Objectives

Similar to an all W divertor but including carbon chemistry

• Effect of Be deposition on carbon release and transport

• Study of Be/C(W) layers, their thermal stability, T-retention

demonstrate that an ITER-like material selection has sufficiently low fuel retention to meet ITER requirements.

STRATEGY: Prepare both options, decide options depending on requirements

Demonstrate operation of ITER scenarios at high current and heating power with Be/C/ W wall choice

EU PWI Task ForceWall material experiments

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

Organisation

Manual + RH Installation now integrated

Be main chamber

NBI Shinethrough protection

Upper Dump plate

Inner wall cladding

Inner wall guard limiters

Saddle coil protection

Saddle coil protection

Outer poloidal limiters

LH + ICRH protection

KC1 coil covers

Total main wall tiles = 4404

Main wall: Be wherever possible , on some areas W coated CFC: responsible JOC (operator)

Global carbon deposition TEC

Institut für PlasmaphysikAssoziation EURATOM-Forschungszentrum JülichV. Philipps, ITPA Tarragona, June 05

Inner Wall Material Distribution

Shinethrough Area

Restraint ring protection

Option for Be coating of inconel cladding is being investigated

W coated CFC 15mm back from limiter edge

X?

Proposals:• Configuration - Final decision 2006• complete set of divertor tile

replacements ordered (marked in red)

→ RD task to IPP Garching for W coating on CFC substrate

→ RD task to FZJ Jülich on W bulk concept

Divertor options

Association “thick” method

“thin” method total number

CEA VPSCVD

CVD 4 and 10 3

ENEA VPS 1

TEKES PVD 4 and 10PVD/Re interl. 4 or 10

3

IPP Garching VPSCVD

PVD (4 and 10)CVD (4 and 10)

6

MEC/CEA CMSII/TVA(probably 10µm by CMSII)

1

: VPS=Vacuum Plasma Spray, CVD=Chemical Vapor DepositionPVD=Physical Vapor Deposition, TVA=Thermionic Vacuum ArcCMSII=Combined Magnetron Sputtering and Ion Implantation

Different Coating Types provided by Associations

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

W coating task, status ( H. Maier IPP )

shipment of coatings to IPP, due Sep 1

status: 10 out of 14 types delivered4 on the way

summary: 14 out of 14 possibly in test program

Meeting oct 7 for final agreement among parties on benchmarking of testing procedures for NDT for the procurement of the coated tiles for the entire divertor

Next steps until february

• Thermal screening of delivered coatings

completion anticipated by mid-november (+accompanying analysis )

Selection process: november

Cyclic loading at IPP, up to end february

Proposed ELM-like loading at FZJ: Under discusion, open issue, time constraints

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

Non-destructive testing: Infrared thermography

Lock-in thermography developed at CEA

Xavier Courtois

Pulsed thermography under developmentat UKAEA

Glenn Counsell,Camera defect !

Benchmarking can only be done with CEA method

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

Design concepts

1. First option: Lamellae design (full W body design)2. Back up option: W brazing design (W + CFC design)

Design limitation1. No active cooling under ~ 7 MW/m2 for 10 s2. Temperature limits (surface temp., temp at fixing structure)3. Weak supporting structure against EM forces4. Weight limit (80 kg/assembly) due to remote handling

The tileLBSRP (270 x 170 x 40 mm3)

ApproachesTemperature distribution by FEMEM forces by FEMMechanical tests for CFC and brazingHHF tests by electron beam facilities

Most critical issues are EM forces in disruptions

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

Bulk W divertor

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

W lamellae design

Forschungszentrum Jülichin der Helmholtz-Gemeinschaft

inward and outward views: approximation of 3D-shaping by tilted planes (shadowing kept)

steps

top view: approximation of toroidal curvature by 2 straight linesref. radius2667 mm

Outward and inward views:

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

W lamellae 50x 6 mm

W lamellae design Opt2

3 fixing screws /stack

New base plate design

New wedge design

Spacers for insulation (TZM+ Al2O3 )

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

Critical issues

Be first wall

mechanical accuracy and stability for castellated structures

Coatings:

Stability of W coating on Dunlop type CFC

Lifetime of W coating (see talk by J. Likonen)

W-bulk

Performance under high heat loads (200 cycles foreseen from 200C (7 MW for 10 sec) + destructive tests

Integration of new support structure in JET engineering

Costs and very narrow time schedule for all systems

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

Many questions remain which can be worked on with help of EU PWI

• Calculations of EM forces

• Diagnostic of W-sources and W in the plasma

• Thermography in a full metal wall surrounding (reflectivity, emissivity)

• Production of fast particles and impact of Be and W erosion in main chamber (in particular with ICRH, LH)

• Modelling of W erosion and transport in divertor and predictions for coating lifetime

• Interaction of W with Be

• In situ diagnostic of material deposition and fuel retention

• Laser desorption/ablation diagnostics (JET FT, EU TP)

• Gas balance

• etcc

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

The main answers on the scientific goals of the JET wall project must be given by

SpectroscopySpecial wall diagnostic probespost mortem tile analysis

in situ fuel inventory/recycling (gas balance )

And the overall evaluation of plasma performance

upgrade of diagnostics needed

Diagnostic for the JET wall project

Embedded diagnostics

Langmuir probes

Thermo-couples

(direct part of the wall project)

Spektros-copy

(W, Be,C)

12.9:expert meeting (FZJ)

4/5.10: kick Off meeting

Responsible persons identified

Working programme defined

Wall diagnostic (probes)

19.9: expert meeting

Responsible persons identified

Be marker

R&D project on markers

Project settled

Project leader M. Rubel

Thermo-graphy

(upper view)

Project

settled

Project leader T. Eich

Working plan approved by PB

Improved Thermo-graphy

6.10: IR expert Working group meeting

Critical projects, not enough support form EU associations

EU-PWI-Task Force

V. Philipps, TF Meeting, 17-19 2005 Cadarache

Be cost will decrease under negotiation

Greatest uncertainty

Inconel 625 is hard

+ 750 for the RH boom

Move to shutdown?

Move to shutdown?

Decide March 2006

Depends on R&D

Article 7 Cost Estimates (kEuros) PB#1 PB#2 Var.

1. Beryllium material 9,000 9,800 800

Scrap beryllium buy-back credit -3,500 -2,800 700

2. Beryllium machining + tile assembly 7,500 7,691 191

3. CFC material 2,600 2,800 200

4. CFC machining 500 464 -36

5. Casting of Inconel carriers and cladding 600 633 33

6. Machining of metallic parts 600 1,425 825

7. Manufacture of fasteners 600 653 53

8. Embedded diagnostics - TC array etc. 1,200 1,248 48

9. Tungsten coating of CFC tiles 1,700 1,700 0

10. Beryllium tile baking facility 300 300 0

11. Bulk Tungsten LBSRP 2,000 2,000 0

Contingency 0 0 0

TOTAL 23,100 25,914 2,814

Main chamber Limiter tile design

Sliced to reduce eddy forces

No visible bolt holes to maximise power handling

Castellated to avoid cracking

IWGL is 3cm thicker than CFC

Global carbon deposition TEC

Institut für PlasmaphysikAssoziation EURATOM-Forschungszentrum JülichV. Philipps, ITPA Tarragona, June 05

W coatings for the divertor

IPP Garching is coordinatingFive EURATOM associations are involved in R&D to develop tungsten coating on JET- type (Dunlop) CFC

Problem:

•Anisotropic therm. expansion of CFC

•Therm. expansion mismatch with W

Strategy:

•Variation of production methods

•Very thin coatings (4µm)

→ Investigation of 4µm, 10µm “thin“ films

In addition:

Possible fallback solution for bulk tungsten

→ 200µm “thick“coatings

Hans Maier

Association “thick” method

“thin” method total number

CEA VPSCVD

CVD 4 and 10 3

ENEA VPS 1

TEKES PVD 4 and 10PVD/Re interl. 4 or 10

3

IPP Garching VPSCVD

PVD (4 and 10)CVD (4 and 10)

6

MEC/CEA CMSII/TVA(probably 10µm by CMSII)

1

: VPS=Vacuum Plasma Spray, CVD=Chemical Vapor DepositionPVD=Physical Vapor Deposition, TVA=Thermionic Vacuum ArcCMSII=Combined Magnetron Sputtering and Ion Implantation

Different Coating Types provided by Associations

Mechanical and heat flux tests of coatings from September this year, decision early 2006

Bulk W divertor prototype in JET

Currently 2 design concepts1. Lamellae design (full W body design)2. W brazing design (W + CFC design)

Design limitation1. No active cooling under ~ 7 MW/m2 for 10 s2. Temperature limits (surface temp., temp at fixing structure)3. Weak supporting structure against EM forces4. Wight limit (80 kg/assembly) due to remote handling

The tileLBSRP (270 x 170 x 40 mm3)

ApproachesTemperature distribution by FEMEM forces by FEMMechanical tests for CFC and brazingHHF tests by electron beam facilities

JET divertor with LBSRP

The most critical questions are EM forces in disruptions

Existing JET CFC tile on mechanical structure ( wedge and base plate)

EM forces calculated by JET and recalculated by FZJ : agreement within a factor of two, at the margin for the dumbbell + screw

40 mm CFC corresponds to < 1 mm W solid plate and few millimetres solid Inconel plate

No solution which meets the EM forces with the present structure unless connecting W teeth to existing CFC target

Toroidal segmentation: 6 mm thick W plates Mechanically assembled

Lamellae design (W body design)Needs design and construction of newMechanical support, compatible with remotehandling

Lamellae and brazing designs

26/9

W brazing design (W + CFC design)

Cw= ~ 20 mmCCFC= 49 - CW mm

W coating

CCFC

CW

A B

CCFC

CW

CCFC

CW

A B

A= ~10-20 mmB= 30 ~ 50 mm

CFC

W

FE model for EM Loading

SM analysis FEM results

preload eddy load

= detachment

V. Philipps, EU-PWI-Task Force, TFE

Agreed diagnostic proposals for FP7 with respect to the new wall project.

1.Upgrading of many spectrometers:

2. Refurbishment of erosion/deposition diagnostics

3. IR Thermography from top (in addition to wide angle IR installed presently)