IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 20061 AUG Physics Program to prepare / in parallel to...
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Transcript of IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 20061 AUG Physics Program to prepare / in parallel to...
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 1
AUG Physics Program to prepare / in parallel to ITER
Aim is to establish the physics base for ITER (and DEMO)
Two main areas of ITER preparation with unique features:
Consolidation of the standard scenario - W components for wall and divertor, - MHD control with ECCD (variable frequency) versatility of heating systems - ELM tailoring and disruption mitigation pellet and killer gas injection
Exploration of 'Advanced' modes beyond standard scenario - Improved H-mode (ITER Hybrid scenario) pulse length/current diffusion time - ITER relevant digital CODAC system
Direct influence on ITER component design
Strategy: - in close collaboration within EU fusion program - supported by strong theory program at IPP - experiments on ASDEX Upgrade and JET
Otto Gruber, ASDEX Upgrade Team
Report on ASDEX UpgradeEURATOM Association
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 2
Hardware extensions in 2005:- towards a C-free first wall all LFS limiters (water cooled) & roof baffle with thin W coating
- 2 steerable ECRH mirrors (movement tested)- first two-frequency gyrotron: leak after commissioning (1 MW / 10 s / 105 & 140 GHz)
guard/
ICRHlimiter
aux.limiter
hor.plate
lower PSL
roofbaffle
2006/2007(planned)
W-coating startingwith campaign
2003/2004
2004/2005
2005/2006
guard/
ICRHlimiter
aux.limiter
hor.plate
lower PSL
roofbaffle
2006/2007(planned)
W-coating startingwith campaign
2003/2004
2004/2005
2005/2006
AUG operation 2006
Operation till 27 April: about 1/3 of program executed
EZ4 damaged (loss of electrical supply for control, no braking)
new CODAC commissioned - reduced cycle time <1.5ms - extended regime recognition & performance control - real-time diagnostics replaces CAMACs)
Significant overlap with W7-X CODAC (joint IPP project XDV)
Pellet Injection Systems: - centrifuge (HFS launch capability, variable pellet size, frequency & velocity) - blower gun (optimized for decoupling ELM pacing and refuelling)
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 3
Technical incident with EZ4 at 27.04.06
flywheel EZ4construction 1986, power 220 MVA, total weight ca. 160 t
number of pulses est. 75.100, operated for est. 7.900 h
flywheel generator
- operation will be resumed after careful assessment by external experts- technical tests with EZ3 in July ?
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 4
AUG uses three flywheel generators as power/energy source EZ2 (1.45 GJ / 167 MVA): toroidal field EZ3 (500 MJ /144 MVA) + EZ4 (650MJ/220MVA): OH, pol.field, add. heating
Present settings for PF coils: reduced power and energy with EZ3 alone allow only 15 % of the last 2000 # (Ip<800 kA, Padd<5 MW, <5 s)
Reduced max. coil voltages (except divertor coils) reduced reactive power consumption (speed)
about 50% of the last 2000 # are still possible Ip=800 kA, 5-10 MW, 5 s Ip= 1 MA, 5-7.5 MW, 3-4 s at lower dens.& triang.
W program (highest priority in 2007) nearly without restriction full ELM and disruption control program restricted high- discharges at low * and *
strongly reduced NTM stabilization schemes
the planned short-term investigations can be done with only minor restrictions medium-term the full power/energy supply is needed for all relevant ITER
work
Operation with reduced generator capacity (EZ2, EZ3)
0
5
10
15
20
EZ
3 (k
A)
0.4 0.6 0.8 1.0 1.2Ip(MA)
EZ3 > 11 kAEZ3 ≤ 11 kA
Limit: 11 kA
A.C. Sips, W. Suttrop
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 5
Influence of ECCD deposition width d on NTM stabilisation
narrow deposition d<W: - decisive is peak jCD I/d (maximal at tor = -5° /TORBEAM)
full stabilisation with dc ECCD at reduced P⇒ ECCD/PNBI
higher ⇒ N achievable at stabilisation broad deposition d > W: - reduces the stabilisation efficiency (experiment) - required current increases significantly for dc ECCD (theory) ⇒ modulated ECCD (at mode frequency / O-point injection) required for ITER
[M. Maraschek et al, PPCF, 2005]only partial dc stabilisation for d > Wdc stabilisation at ITER relevant conditions
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 6
Full stabilisation of (3,2) NTM with modulated ECCD (d>W)
ECCD modulated with phase from magn. signals with fmode < 30kHz reduced overall deposited ECCD power complete stabilisation at high N / <PECCD> ~ 4.0 MW-1
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 7
Combination of high power, flexible addititional heating, current and shaping capability, density operation up to Greenwald and long pulse length (> current diffusion time) allows unique exploration of advanced scenarios beyond ITER baseline Improved H-Mode in ITER allows Q>30 and / or pulselength above 1 h Improved H-Mode may allow even ‚steady state‘ in DEMO
Scenario development for ‚Improved H-Mode‘ (Hybrid mode)
4
open: <10E
closed: >10E
N
ITER
ITPA
i*
JET
DIII-DAUG
JT-60U
0
1
2
3
0 5e-3 1e-2 1.5e-2
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 8
Scenario development for ‚Improved H-Mode‘ (Hybrid mode)
early versus late heating
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 9
Scenario development for ‚Improved H-Mode‘ (Hybrid mode)
early versus late heating
pol
pol
Reich, Stober
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 10
(3,2) NTM stabilisation in improved H-mode (dc ECCD, d<W)
clear stabilisation with increasing / decreasing Bt ramp fishbones and sawteeth after stabilisation; good confinement H98-P=1.15 lowest achieved q95=2.9 for stabilised NTMs Maraschek, Stober
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 11
Fast particle losses caused by MHD activity
FILD spectrogram shows fast particle losses well correlated
with TAE activity (NBI, ICRH, ICRH beat waves)
- ICRH creates trapped fast particles
- vperp/v ~0.9,
energy up to several hundreds keV
- TAEs modify orbits of fast particles
Munoz, K. Sassenberg, PhD, Cork, Ireland
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 12
Fast particle losses caused by MHD activity
FILD spectrogram shows fast particle losses well correlated
with NTM activity
- slow MHD activity like NTM (~5-20 kHz, harmonics) induces fast particle losses
- decrease of losses observed when NTM is actively stabilized with ECCD- modulated NBI experiments allow for studying time scales of losses
Munoz, PhD
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 13
Main thrusts for AUG program 2007 w. full W coverage
Re-evaluation after 3 months of operation
I. W compatibility of ITER related scenarios - characterization of transition to a W machine - storage / release of noble gases - optimization of ICRH II. Extension of working space - radiatively cooled integrated scenarios - improved H-Mode (high low density)
III. Other ITER related physics investigations, compatible with above results and requirements
envisaged rel. weight(whole campaign)
priority
30%
20%
50%
Power / Energy Limits set by operation with EZ2/EZ3 only
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 14
Boundary conditions set by W-PFCs (to be refined):
- W concentration slowly increasing with coverage, saturation around 10-5 - reduced cW at relevant auxiliary heating power and densities
- carbon inventory decreasing
Needed for ITER compatible W concentration: density > 6e19/m³ (gas puff rate > 6e21/s) q-edge > 3.2 f(ELM) > 60 Hz ELM pacing dominant central heating Pheat< Pthreshold or Pheat> 2x Pthreshold
power/energy limits for upper divertor (5 MW 4s, 10MW 1s) monitoring of limiter & divertor glow (safety loops)
W concentration
line aveaged electron density
all dataq<3.5 andPICRH>1 MWq<3.5 andPICRH>1 MW (2005/06)
10-7
10-5
10-3
R. Neu, PSI06
IEA IA PolDiv ExCo-Meeting, Cadarache 28 June 2006 15
Consolidation of ITERStandard operation
Preparation of ITERAdvanced operation
2005 2006 2007 2008 2009 2010
LHCD (projected)
Tungsten Wall
ECRH Extension
Modular Flywheel Generator(s)
Internal Coils
Conducting shell
Design Construction Operation
Future AUG hardwre extensions