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1L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP
Overview of Experimental Results on the HL-2A Tokamak
Southwestern Institute of PhysicsP. O. Box 432, Chengdu 610041, China
L.W. Yan, X.R. Duan, X.T. Ding, J.Q. Dong, Q.W. Yang, Yi Liu, X.L. Zou, Yong Liu, and HL-2A team
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2L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP
• Characteristics of ELMy H-mode • Transport study with ECRH
�Particle transport modulated by ECRH �Core transport reduction triggered by ECRH switch-off
• Zonal flows & filament characteristics�Low frequency zonal flows and GAMs�Filament characteristics
• Energetic particle induced modes�Beta-induced Alfvén eigenmode �Beta-induced Alfvén acoustic eigenmode
• SMBI fueling • Summary
Outline
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3L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Introduction of HL-2A tokamak•R: 1.65 m•a: 0.40 m•Bt: 2.7 T•Configuration:Limiter, LSN divertor
• Ip: 450 kA•ne: ~ 6.0 x 1019 m-3•Te: ~ 5.0 keV•Ti: ~ 2.8 keV
Auxiliary heating systems:ECRH/ECCD: 3 MW(6×0.5 MW/68 GHz/1 s)modulated: 10~30 Hz; 10~100 %NBI: 1.5 MW/45 keV/2 sLHCD: 1 MW(2 ×0.5 MW/2.45 GHz/1 s)
Fueling systems (H2/D2):Gas puffing (LFS, HFS, divertor)Extruded PI (40 pellets/LFS, HFS)SMBI (LFS, HFS)LFS: f =10~60 Hz, pulse>0.5ms Gas pressure: 0.3-3.0 MPaHFS: f = 1-5 Hz, 0.2-1.0 MPa
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4L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Two L-H transitions with SMBI fuelling • ELMs appear at 640 ms with
ne=1.8×1019 m-3 rise for 30 ms • The ELMs H-mode remains for 100
ms and then disappears after the SMBI is turned off
• The WE, ne and Prad rise again after the SMBI fuelling is added at t = 770 ms with ne=1.5×1019 m-3
• The clear ELMs appear at 793 ms with ne~1.7×1019 m-3 and disappear at 851 ms, 8 ms after NBI heating is turned off
• The overall discharge exhibits a series of L-H-L-H-L transitions with SMBI fueling
155165
I p (kA
)
1.52.02.5
n e(m-
3 )
0400800
P(kW
)
100200300
P rad(k
W)
102030
WE (
kJ)
24
SMBI
400 500 600 700 800 9000
0.51
t (ms)
D α div
(a.u.)
0.050.10.15
D α, s
(a.u.)
×1019
(g)
(h)
(f)
(e)
(b)
(d)
(a)shot 11565
ECRH(c) NBI
Y. Huang, EXS/P3-02, Wed. AM
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5L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Characteristics of ELMy H-mode
• H-mode achieved by ECRH and NBI• ELM periods are a few milliseconds• Some ELMs have periods of 10-30 ms
with energy loss more than 10 %• Power threshold rises with density drop• Minimum Pth=1.1 MW at ne=1.8×1019 m-3
0123
04812
0400800
0400800
600 700 800 90000.71.4
time (ms)
00.71.4
600 650 700 7500
1
time (ms)
(a)
SMBI→
PNBI(kW)PECRH(kW)
Dα-div
#11565
(b)#11605
Dα-div
←ne(1013cm-3)
Dα-div
#13820
1.2 1.4 1.6 1.8 2.00.8
1.2
1.6
Ptot4 Pth
P (M
W)
ne (1019 m-3)
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6L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Density pedestal width
• MW reflectometry and probes for pedestal width• Pedestal density is 1.25××××1019 m-3 with nped/ne = 0.6• Density pedestal width is about 2.8 cm
15 20 25 30 35 40 45 5000.20.40.60.81
1.21.41.61.8
r(cm)
ne(10
19m-
3 )
RLPMWR, 650msMWR, 350ms
PSep.
HPed~1.25×1019m-3
LFS
H-mode
Gradient
WPed~2.8cm
Ohmic regime
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7L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Outline• Characteristics of ELMy H-mode • Transport study with ECRH
�Particle transport modulated by ECRH �Core transport reduction triggered by ECRH switch-off
• Zonal flows & filament characteristics�Low frequency zonal flows and GAMs�Filament characteristics
• Energetic particle induced modes�Beta-induced Alfvén eigenmode �Beta-induced Alfvén acoustic eigenmode
• SMBI fueling • Summary
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8L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP
Amplitude and phase of density perturbation for the first harmonic modulated by ECRH in limiter (a) and in divertor (b) configurations
• Particle outward convection is observed during pump-out transient phase due to ECRH
• Negative density perturbation propagates much faster than the positive one caused by out-gassing
Particle pump-out during ECRH transient
W.W. Xiao, PRL 104 (2010) 215001X.L. Zou, EXC/P8-20, Fri. PM
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9L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Te0 rises after far off-axis ECRH switch off
(a) After far off-axis ECRH switch-off (rdep/a=0.69), the Te0 suddenly rises and remains for a few tens of milliseconds before it drops(b) The Te0 increment appears inside q = 1 surface, corresponding to an ITB formation near q = 1 surface
(b)
0
0.5
1
1.5T e
(eV)
350 400 450 500 550 600 65000.51
1.5
n e(10
19m-
3 )
t(ms)
ECRH
r=-24.2cm
#13593
I II
sawtooth
r=-17.0cm
r=-9.0cm
r=-0.1cm
0
0.5
1
1.5
-35 -30 -25 -20 -15 -10 -5 0
#13593 380ms480ms540ms
T e(ke
V)
r(cm)
ECRH
q=1
(a)
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10L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP
• Microwave reflectometer power spectrum near q=1 surfaceafter ECRH switch-off is much lower than that before or during ECRH, consistent with Te0 rise
Clear drop in ne0 fluctuation
100 101 102
10-1
100
101
f(kHz)
P(a.u.
)
380ms480ms540ms
#13593
afterECRH
ECRHbeforeECRH
Z.B. Shi, EXC/P8-14, Fri. PM
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11L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Outline
• Characteristics of ELMy H-mode • Transport study with ECRH
�Particle transport modulated by ECRH �Core transport reduction triggered by ECRH switch-off
• Zonal flows & filament characteristics�Low frequency zonal flows and GAMs�Filament characteristics
• Energetic particle induced modes�Beta-induced Alfvén eigenmode �Beta-induced Alfvén acoustic eigenmode
• SMBI fueling • Summary
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12L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP ZF spectrum variation with PECRH & q(a) Intensities of the
LFZFs and GAMs rise with ECRH power
(b) The LFZF intensities increase but the GAMs decrease when the edge safety factor q decreases from 6.2 to 3.5
K.J. Zhao, EXC/7-3, Fri. AM A.D. Liu, PRL 103 (2009) 095002
1 10 10002468
powe
r(a,u)
f(kHz)
1 10 1000
1
2
3powe
r(a,u)
(a)
(b)
GAM
q=6.2q=5.2
q=3.5
380kW
680kw
GAM
LFZF
LFZF
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13L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Radial Er power for zonal flows
(a) The intensity of LFZF power first increases slightly and then sharply rises at ~2.5 cm away from LCFS
(b) The GAM power has a maximum at ~1.5 cm awayfrom LCFS
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14L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Large scale structure in SOL
(a) Poloidal and radial sizes are less than 1 cm, measured by poloidal 10-tip and radial 8-tip arrays, separated by 210 cm toroidally
(b) Maximum coherence is 0.91 along a magnetic field line(c) Near zero k// is in line with the interchange mode driven mechanism
J. Cheng, EXD/P3-05, Wed. AM
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15L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Filament propagation
• The poloidal-radial images with time interval of 5 µs• Filament poloidal and radial sizes less than 1.0 cm• Two filaments with space of 22 mm and lifetime of 25 µs
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16L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Outline• Characteristics of ELMy H-mode • Transport study with ECRH
�Particle transport modulated by ECRH �Core transport reduction triggered by ECRH switch-off
• Zonal flows & filament characteristics�Low frequency zonal flows and GAMs�Filament characteristics
• Energetic particle induced modes�Beta-induced Alfvén eigenmode �Beta-induced Alfvén acoustic eigenmode
• SMBI fueling • Summary
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17L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP
time (ms)
f (kHz
)
200 400 600 800 1000 12000102030
-0.50 0.5
0.5
1
e-BAE
ECRHMir (a.u) NBI
m-BAE
( )a
( )b
( )c
ne (1019 m-3)
TMnoise
1.5 2 2.58
12
16
20
24
Bt/ne1/2
f (kHz
)
a
Bt in [T]ne in [1019 m-3]
BAE excited by energetic electrons
• The e-BAE is observed during ECRH for the first time• Large magnetic island induces m-BAE at t = 1220 ms• The BAE frequency increases with VA• The fBAE is much less than fTAE
W. Chen, EXW/4-4Rb, Wed. PMW. Chen, PRL 105 (2010), accepted
ECRH plasma
• Ip = 160 kA, Bt =1.3 T, qa ≈ 4.0, Ti ≈ 0.85 keV• Te≈1.1 keV, PNBI = 0.4 MW, PECRH = 0.9 MW
( )Shot 10579
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18L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP BAE correlation with energetic electrons 15
36
HX c
ount
1
0.82.4
time (ms)
f (kHz
)
400 500 600 700 800 90001020304050
20-30
( )f
( )b
( )a
( )c
( )d
30-40
10-20 keV
ECRH ne(1019m-3)
( )e
e-BAE
• Beta-induced Alfvén eigenmode appears when the number of energetic electrons with energy of 10-40 keV is high enough
• The mode number of e-BAE is m/n = -3/-1
Shot 13364• Ip = 320 kA• Bt = 2.4T, • qa ≈ 4.0, • Te ≈ 2.3 keV• PECRH =1.4 MW• X-rays detected by Cadmium-telluride (CdTe)
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19L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Beta-induced Alfvén acoustic eigenmode
• BAAE with f = 15-40 kHz identified by frequency up-chirping, consistent with the solution for Alfvén-acoustic continuum
• A clear spectrum splitting is first observed on BAAE
Shot 10391•Ip = 170 kA•Bt = 1.4T, •qa ≈ 4.0, •Te ≈ 1.0 keV•Ti ≈ 0.8 keV•PNBI =0.6 MW
Alfvén-acoustic mode
Tearing mode
Splitting
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20L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP
0 0.1 0.2 0.3 0.4 0.5 0.60
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
r/a
Ω2
m=2 n=2t=560ms
uncoupled Alfven branch
km-1 acoustic branch
Radial range of BAAE gap
BAAE gap
Yi Liu, EXW/P7-15, Fri. AM
• Alfvén-acoustic coupling continuum (Blue & Green)for HL-2A plasma from numerical solution of ideal MHD equations incorporated both the shear Alfvén (azure) and the acoustic (red) branches.[N.N. Gorelenkov, Physics Letter A 370(2007)]
• BAAE is only observed by SXR in the central region
• BAE can be observed by SXR and Mirnov signals
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21L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Outline• Characteristics of ELMy H-mode • Transport study with ECRH
�Particle transport modulated by ECRH �Core transport reduction triggered by ECRH switch-off
• Zonal flows & filament characteristics�Low frequency zonal flows and GAMs�Filament characteristics
• Energetic particle induced modes�Beta-induced Alfvén eigenmode �Beta-induced Alfvén acoustic eigenmode
• SMBI fueling • Summary
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22L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP SMBI fuelling efficiency
(a) SMBI fuelling efficiency from HFS is higher than that from LFS
(b) Fuelling efficiency reduces a little from the HFS but about one half from the LFS for powerful ECRH
• The fuelling efficiency of SMBI is 40~60 % for a limiter configuration and 30-40 % for a divertor configuration
D.L. Yu, EXC/P8-22, Fri. PM
1.0
1.5
2.0n e
( ×1019
m-3
)
400 500 600 700 800 9000.5
1.0
1.5
time (ms)
n e (10
19 m
-3)
w/o ECRH
w/ ECRH
(a)
(b)
δne=0.63 δne=0.76
δne=0.60 δne=0.30
LFS SMBIHFS SMBI
LFS SMBIHFS SMBI PECRH=1.3MW
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23L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP
New Diagnostics: MSE,ECEI, FIR polarimetry, etc.
Now Under development NBI (MW) 1.5 1.5
ECRH (MW) 3 2LHCD (MW) 1 2
Heating systems:
Hardware development in the near future
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24L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP Summary• Typical ELMy H-mode was achieved with pedestal width of ~2.8 cm.• Negative density perturbation during ECRH pump-out propagates
much faster than the positive one caused by out-gassing.• The Te0 inside q = 1 surface rises after far off-axis ECRH power switch off, consistent with core turbulence suppression.• The LFZF intensities increase but GAMs decrease when qa drops from 6.2 to 3.5. Both intensities rise with ECRH power. • Near zero k// for plasma filaments is observed along a field line, in agreement with the interchange mode driven mechanism.• BAEs excited by energetic electrons of 10 - 40 keV during ECRH
are observed for the first time.• A core localized BAAE is identified by its frequency up-chirping,
and a clear frequency splitting is first observed.• The SMBI efficiency fuelled from HFS is higher than that from LFS.
It reduces a little but about one half for high power ECRH plasma.
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25L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP
• K.J. Zhao EXC/7-3, Fri. AM • W. Chen, EXW/4-4Rb, Wed. PM• Q.W. Yang, EXS/P2-20, Tue. PM• Y. Huang, EXS/P3-02, Wed. AM• J. Cheng, EXD/P3-05, Wed. AM• Yi Liu, EXW/P7-15, Fri. AM• Z.B. Shi, EXC/P8-14, Fri. PM• X.L. Zou, EXC/P8-20, Fri. PM• D.L. Yu, EXC/P8-22, Fri. PM
HL-2A Experimental Results presented at this conference
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26L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP 23rd IAEA FEC, 12 Oct. 2010, Korea, OV4-5
In collaboration withUniversity of Science and Technology of China, Hefei, ChinaASIPP, Hefei, ChinaCEA, IRFM, Cadarache, FranceMPI für Plasmaphysik, GermanyNIFS, Toki, Japan Kyoto University, Kyoto, JapanAcknowledgementsGA, PPPL, LLNL, UCI, UCLA, UCSD, USAJAEA, Kyushu U., JapanENEA, Frascati, ItalyIPP-Juelich, GermanyKurchatov Institute, RussiaFOM-Institute for plasma physics Rijinhuizen, Netherlands HUST, IOP, Tsinghua University, China
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27L.W. Yan, Overview on HL-2A, 23rd IAEA FEC, 11-16 Oct. 2010, Daejeon, Republic of Korea
HL-2ASWIP
Thank you for your attention !