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
1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015
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
5 1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015
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
6 1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015
ASIPP
E-beam welding of PFCs
60 kV, 6 kW
1 m
1 m
1.4 m
7 1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015
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!
9 1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015
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
1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015
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
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
12 1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015
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
15 1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015
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
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
19 1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015
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.
20 1st IAEA TM on Divertor Concepts, Sep 29 - Oct 2, Vienna, 2015
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