iter-like tungsten divertor development and experiments on ... · tungsten interactions (pwi) have...

ASIPP

ITER-like Tungsten Divertor Development and Experiments on EAST

L. Wang, G. -N. Luo*, Q. Li, F. Ding, W. J. Wang, D. M. Yao, G. S. Xu, H. Y. Guo, Y. Liang, Y. W. Sun, X. Z. Gong, B. N. Wan, J. Li and X. D. Zhang

1st IAEA TM on Divertor Concepts, Vienna, Sep 29 - Oct 2, 2015

*E-mail: [email protected]

Institute of Plasma Physics, Chinese Academy of Sciences

ASIPP

Outline

1. Development of W/Cu Divertor on EAST – Engineering – Commissioning

2. Experiments of W divertor operation – Experimental results in 2014 – Preliminary results in 2015

3. Summary & Outlook

2 1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015

ASIPP

Structure Design and Evaluation

3

EAST upper tungsten divertor has modular structure with 80 modules in total. Each module supported by inner/outer rail and middle support.

DOME

OVT IVT

Cassete Body (CB)

Monoblock-PFU

Module = CB + IVT + DOME + OVT

1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015

ASIPP

4

PFCs Configuration and Connections

End Box (flat type)

Monoblock units by Diffusion bonding Brazing (for legs)

Baffles (flat type)

Connecting plate

EB welding

DOME

OVT

IVT


ASIPP

ITER-like Monoblock W/Cu PFUs

• HIP+HIP: W/Cu mockups were manufactured successfully by a double Hot Isostatic Pressing (HIP) technology

• NDT results: Passed NDT check for dual bondings between W/OFC/CuCrZr tube; HHF testing: 10MW/m2-1000cycles passed

Bulk W-monoblock

CuCrZr tube - HIP

OFC interlayer - HIP


ASIPP

Flat-type W/Cu PFUs • Casting + HIP: The interface of W/Cu were joined by casting,

and then the interface of Cu/CuCrZr was bonded by HIP at lower temperature of 500~600℃.

• NDT results: Passed NDT check for dual bondings between W/OFC/CuCrZr plate; HHF testing: 5MW/m2-1000cycles passed

Casting or VPS/CVD

VHP

or gradient W/Cu layer


ASIPP

E-beam welding of PFCs

60 kV, 6 kW

1 m

1 m

1.4 m


ASIPP

Module: 80pcs Monoblock W: 15,000pcs Flat W tiles: 24,000pcs E-beam seam: > 5000pcs CuCrZr plates: > 8tons CuCrZr tubes: 720pcs/360m

Assembly

2015-06-10 21st ITPA-DSOL Meeting, PPPL, June 9-12, 2015 8

ASIPP

Commissioning in 2014 • Twice leak events during baking at 170℃, and first

repaired and second evacuated (given-up) • Baking at the end of campaign at 270℃ to test

PFCs and find put weak points (possible leaks) • After campaign, found 13 leak points and some W

tile damages, w/certain or uncertain causes!


ASIPP

Repair/Optimization in 2015

• Cooling tube connection: TIG welding -> soft bellows • QA&QC for EBW btw tube

and heat sink enhanced • PFCs+CB baking at 250℃

prior to assembly in VV

10

Bellows

沿此处切除

沿原焊缝切除

3D-Printing of broken support leg


ASIPP

Commissioning in 2015

1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015 11

Baking : 180~200℃ Plasma discharge in June-July W-divertor operation in July No leaking in 2015

W

Mo

C

ASIPP

Outline





ASIPP

H mid-plane port

Outer target plane (L section)

Inner target plane (H section)

Spectroscopy system: Spectrometer & Filter + PMT 350nm - 800nm 300 / 600 /1200 /1800 /3600 l/mm gratings Spatial resolution: 13 mm (poloidal) Time resolution: 200 Hz (12 channels, EMCCD) Max. 20 kHz (PMT)

Monitoring W source on EAST

13

ASIPP

W source in type I ELMy H mode plasma

400KA, LSN, NBI L+R 3MW

A strong W source appears during type I ELMs, together with other impurities including C, Li, etc., and inter-ELM vs Te

14

ASIPP

Poloidal distribution of intra-ELM W influx presents a significant increase at strike point region, corresponding to Te distribution at divertor.

W source in type I ELMy H mode plasma


ASIPP

Long pulse W divertor operation in 2015

0

100

200

300

400

500

tem

pera

ture

o C

#57499 upper-outer-divertor

0 5 10 15 20 25 30 350

2

4

6

Time(s)

Da

（ a.u）

Shot#57499: Ip=370kA, Bt=2.25T, ne=4.5E19, PLHW~2MW, PICRF ~1.6MW

Under evaluation

Divertor target surface temperature saturates after ~10s. 16

ASIPP

Plasma detachment in USN W divertor

L-mode： Ip=400kA, Bt= 2.25 T, ne=2.5 4.5 x1019m-3, PLHW~1.5MW

3.5s 4.5s 7s

17

ASIPP

In-out asymmetry of divertor particle fluxes during ELMs

LSN, C-divertor, Normal Bt

USN, W-divertor, Normal Bt ELM particle flux favors outboard divertor in USN, while favors inboard divertor in LSN. Provides reference for particle

exhaust during long-pulse H-mode operation. Consistent with PS flow, as

measured by LFS reciprocating Langmuir probes.

18

ASIPP

Outline





ASIPP

Summary & Outlook

EAST upgraded its upper divertor into full W/Cu-PFCs, employing HIP technology and e-beam welding in 2014.

Commissioning in 2014 found leak and damage in the EAST W divertor. Repairing & optimization exhibits technology success in the 2015 campaign.

Preliminary divertor experiments & study on plasma-tungsten interactions (PWI) have been carried out.

W divertor for long-pulse high performance operation of EAST will be attempted in the coming campaigns.

Series of experiments to study W-divertor capabilities, performance, Div-SOL physics and PWI are planned.


ASIPP

Thank you!

Welcome collaborations!

21 EAST – Test Bed for ITER & CFETR

ASIPP

B×▽B↓

Initial comparison of W/C divertor particle exhaust capability with Li coating

22

dRsep (m)

Total puff (0-7s): USN=1.65E22 D, LSN=1.55E22 D； More input data are needed to draw an USN/LSN comparison conclusion, especially for long pulse operation.

ASIPP

Tungsten/Wall diagnostics

23

ASIPP

Heat and particle flux diagnostics

24

Parameters to be measured: nt, Tt, Vf, particle & heat fluxes toroidal asymmetry …

Spatial resolution: 12-18mm@UI&UO; 15mm@LI,10mm@LO

Time resolution: 20µs Power supplier: DC 200V, 3A/10A PWI, divertor and 3D Phys. studies.

toroidal

Upper div-LP arrays in ITER-like W monoblock

Div-probe array：Ports D & O IR thermography Parameters to be measured:

Divertor surface temperature, Target heat flux

Field of view: 47°×58° Temporal resolution:

8.7ms (full frame) 0.86ms (1/4 frame) 0.34ms (132*3)

Spatial resolution: 4 mm

24

iter-like tungsten divertor development and experiments on ... · tungsten interactions (pwi) have...

Documents