otto gruber for the asdex upgrade team
DESCRIPTION
Max-Planck-Institut für Plasmaphysik, EURATOM Assoc.-IPP. Overview of ASDEX Upgrade Results. Otto Gruber for the ASDEX Upgrade Team. Presented at the 21st IAEA Conference at Chengdu (China), 16 – 21 Oct 2006. Max-Planck-Institut für Plasmaphysik, EURATOM Assoc.-IPP. ASDEX Upgrade Team: - PowerPoint PPT PresentationTRANSCRIPT
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 1
Otto Gruber for the ASDEX Upgrade Team
Overview of ASDEX Upgrade Results
Max-Planck-Institut für Plasmaphysik, EURATOM Assoc.-IPP
Presented at the 21st IAEA Conferenceat Chengdu (China), 16 – 21 Oct 2006
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 2
ASDEX Upgrade Team:
C. Angioni1, C.V. Atanasiu2, M. Balden1, G. Becker1, W. Becker1, K. Behler1, K. Behringer1, A. Bergmann1,T. Bertoncelli1, R. Bilato1, V. Bobkov1, T. Bolzonella3, A. Bottino1, M. Brambilla1, F. Braun1, A. Buhler1,A. Chankin1, G. Conway1, D.P. Coster1, T. Dannert1, S. Dietrich1, K. Dimova1, R. Drube1, R. Dux1, T. Eich1, K. Engelhardt1, H.-U. Fahrbach1, U. Fantz1, L. Fattorini4, R. Fischer1, A. Flaws1, M. Foley5, C. Forest6,P. Franzen1, J.C. Fuchs1, K. Gál7, G. Gantenbein8, M. García Muñoz1, L. Giannone1, S. Gori1, S. da Graça1,H. Greuner1, O. Gruber1, S. Günter1, G. Haas1, J. Harhausen1, B. Heinemann1, A. Herrmann1, J. Hobirk1,D. Holtum1, L. Horton1, M. Huart1, V. Igochine1, A. Jacchia9, F. Jenko1, A. Kallenbach1, S. Kálvin7, O. Kardaun1,M. Kaufmann1, M. Kick1, G. Koscis7, H. Kollotzek1, C. Konz1, K. Krieger1, H. Kroiss1, T. Kubach8, T. Kurki-Suonio10, B. Kurzan1, K. Lackner1, P.T. Lang1, P. Lauber1, M. Laux1, F. Leuterer1, J. Likonen11, A. Lohs1,• Lyssoivan12, C. Maggi1, H. Maier1, K. Mank1, A. Manini1, M.-E. Manso4, P. Mantica9, M. Maraschek1,P. Martin3, M. Mayer1, P. McCarthy5, H. Meister1, F. Meo13, P. Merkel1, R. Merkel1, V. Mertens1, F. Merz1,H. Meyer14, F. Monaco1, H.-W. Müller1, M. Münich1, H. Murmann1, Y.-S. Na1, G. Neu1, R. Neu1, J. Neuhauser1,J.-M. Noterdaeme1, M. Pacco-Düchs1, G. Pautasso1, A.G. Peeters1, G. Pereverzev1, S. Pinches1, E. Poli1,M. Püschel1, T. Pütterich1, R. Pugno1, E. Quigley5, I. Radivojevic1, G. Raupp1, M. Reich1, T. Ribeiro4, R. Riedl1,V. Rohde1, J. Roth1, M. Rott1, F. Ryter1, W. Sandmann1, J. Santos4, K. Sassenberg5, G. Schall1, H.-B. Schilling1,J. Schirmer1, A. Schmid1, W. Schneider1, G. Schramm1, W. Schustereder15, J. Schweinzer1, S. Schweizer1,B. Scott1, U. Seidel1, M. Serbu1, F. Serra4, Y. Shi16, A. Silva4, A.C.C. Sips1, E. Speth1, A. Stäbler1, K.-H. SteuerJ. Stober1, B. Streibl1, D. Strintzi1, E. Strumberger1, W. Suttrop1, G. Tardini1, C. Tichmann1, W. Treutterer1,C. Tröster1, M. Tsalas17, L. Urso1, E. Vainonen-Ahlgren11, P. Varela4, L. Vermare1, D. Wagner1, M. Wischmeier1,E. Wolfrum1, E. Würsching1, Q. Yu1, D. Zasche1, T. Zehetbauer1, M. Zilker1, H. Zohm1.
Max-Planck-Institut für Plasmaphysik, EURATOM Assoc.-IPP
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 3
Max-Planck-Institut für Plasmaphysik, EURATOM Assoc.-IPP
Contributing Institutes
1 Max-Planck-Institut für Plasmaphysik, EURATOM Association-IPP, Garching, Germany2 Institute of Atomic Physics, EURATOM Association-MEdC, Romania,3 Consorzio RFX, EURATOM Association-ENEA, Padova, Italy, 4 CFN, EURATOM Association-IST Lisbon, Portugal, 5 Physics Dep., University College Cork, Association EURATOM-DCU, Ireland, 6 University of Wisconsin, Madison, USA. 7 KFKI, EURATOM Association-HAS, Budapest, Hungary, 8 Institut für Plasmaforschung, Stuttgart University, Germany, 9 IFP Milano, EURATOM Association-ENEA, Italy, 10 HUT, EURATOM Association-Tekes, Helsinki, Finland, 11 VTT, EURATOM Association-Tekes, Espoo, Finland, 12 LPP-ERM/KMS, EURATOM Association-Belgian State, Brussels, Belgium, 13 NL Risǿ, EURATOM Association-RISØ, Roskilde, Denmark, 14 UKAEA Culham, EURATOM Association-UKAEA, United Kingdom, 15 University of Innsbruck, EURATOM Association-ÖAW, Austria 16 IPP, CAS, Hefei, China, 17 NCSR Demokritos, EURATOM Association-HELLAS, Athens, Greece
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 4
Main aim is to establish the physics base for ITER (and DEMO): - consolidation of the 'standard' H-mode scenario - exploration of ‚advanced' modes beyond the standard scenario
Understanding of physics elements
- transport
- fast particles and NBCD
- H-mode edge and ELM tailoring
- disruption mitigation
- MHD control with ECCD
- tungsten wall and divertor operation
Integration into improved scenario beyond reference - Improved H-mode (ITER Hybrid scenario) - ITER relevant digital CODAC system
Direct influence on ITER component design: PFC material, heating/CD systems, ECRF system
Strategy: in close collaboration within EU fusion programme, ITPA TGs
AUG programme to prepare / in parallel to ITER
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 5
towards a tungsten first wall: 36 m2 or 85% of PFC area) 2005: - all LFS limiters (water cooled) - roof baffle with thin W coating (<4 m PVD) 2006: lower divertor target plates (200 m W VPS)
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 enhancements 2004-2006:
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 6
AUG enhancements: Towards a full W machine 2005
● in 2005 “thin” W coating of - 4 guard limiters at LFS (water cooled) - 8 ICRH antenna side limiters - top of bottom PSL - roof baffle
● in 2006 - upper and lower ICRH limiters - W coated bottom target tiles (200 m)
full tungsten machine
ITER start-up configuration ?
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 7
towards a tungsten first wall: 36 m2 or 85% of PFC area) 2005: - all LFS limiters (water cooled) - roof baffle with thin W coating (<4 m) 2006: lower divertor target plates (200 m W)
4 steerable ECRH mirrors installed
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 enhancements 2004-2006:
pellet injection systems - centrifuge (HFS launch capability, variable pellet size,< 1200 m/s) - blower gun (optimized for decoupling ELM pacing and refuelling)
new CODAC commissioned - reduced cycle time <1.5ms - extended regime recognition & performance control - real-time diagnostics replaces CAMACs
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 8
Understanding of anomalous transport predictions
- response of different transport channels on heat and momentum input- comparison with gyrokinetic simulations TEM and ITG turbulence dominate in different parameter regimes
Pure electron heating: threshold for TEM at R/LTe3
power balance and heat pulse propagation show a transition through threshold
Angioni EX/8-5Rb
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 9
Transport: Er transitions at plasma edge
negative Er well increases
with confinement improvement
- coincides with H-mode barrier gradient
- Doppler reflectometry
Conway EX/2-1
H98(y,2)
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 10
Fast particle interactions with large scale instabilities
- New: Fast Ion Loss Detector (FILD) with bandwidth of 1 MHz
- frequency / phase correlations of fast ions with TAEs (ICRH, ICRH beatwave)
- fast particle losses correlated with low frequency MHD activity: NTMs, double tearing modes, ELMs
- slow MHD activity like NTM (+harmonics) induces fast particle losses
- FILD signal is modulated with rotating mode in fixed phase relation
- modulated NBI sources with different injection geometry origin of fast particles- time scale of losses >100 toroidal orbit transits due to stochasticity of overlapping drift islands caused by the NTM
- NTM stabilization decrease of losses
Günter EX/6-1
(2,1)
Fast ion losses trackthe details of the mode
f (kHz)
time (s)
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 11
Unexpected broadening of NBI driven currents
Switch on / off-axis at 4.1 s
UL(V)
4.2 s 0.1 s
3.5-4.0 s
- beyond a certain heating power, measured and predicted distributions of NBI driven currents deviate (MSE, TRANSP)
- electric field changes cannot be explained by current diffusion
Günter EX/6-1, McCarthy TH/P3-7
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 12
Unexpected broadening of NBI driven currents
- beyond a certain heating power, measured and predicted distributions of NBI driven currents deviate (MSE, TRANSP)
- electric field changes cannot be explained by current diffusion
Günter EX/6-1, McCarthy TH/P3-7
Switch on / off-axis at 4.1 s
UL(V)
4.2 s 0.1 s
3.5-4.0 s
4.3 s 4.4 s 4.5 s
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 13
Unexpected broadening of NBI driven currents
- beyond a certain heating power, measured and predicted distributions of NBI driven currents deviate (MSE, TRANSP)
- electric field changes cannot be explained by current diffusion
energetic particle diffusion driven by small-scale turbulence (gyrokinetic code)
redistribution of injected ions
with Dfast0.5 m2/s
Günter EX/6-1
Switch on / off-axis at 4.1 s
UL(V)
4.2 s
3.5-4.0 s
4.3 s 4.4 s 4.5 s
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 14
ELMs and disruptions
Neuhauser EX/P8-2
• most of the ELM and disruption energy is deposited in the divertor• a smaller fraction goes to the main chamber wall
ELMs:- helical field aligned structures with a 3-6 cm spatial width and 3-6 km/s rotation velocity - move radially far into the SOL (LFS)- heat flux decay length 2-3 cm- particle flux decay length comparable
- consistent with convective loss along field lines
ITER: small ELM regimes / ELM pacemaking & disruption mitigation mandatory
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 15
ELMs and disruptions
Pautasso EX/P8-7
• most of the ELM and disruption energy is deposited in the divertor• a smaller fraction goes to the main chamber wall
Disruptions:- mitigation by puffing of noble gases (Ne)
regularly used at AUG
- significant reduction of force loads on all structures- divertor heat load mainly reduced by broader radiation and heat deposition profiles in divertor- further optimization needed: higher gas pressure and amount
ITER: small ELM regimes / ELM pacemaking & disruption mitigation mandatory
Erad (kJ)
vertical bolometer channels
w/o gas puff
w. gas puff
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 16
NTM stabilization: Influence of ECCD deposition width d
narrow deposition W>2d: - IECCD counts for helical CD
- full stabilisation with dc ECCD of (3,2) and (2,1) NTMs
- no advantage of phased ECCD
broad deposition W<2d:
- mimics ITER Wmarg~pol
- IECCD/d2 counts for dc ECCD
- only partial dc stabilization
- required current increases significantly ⇒ modulated ECCD required
(at mode frequency / O-point injection)
tor
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 17
NTM stabilization: Modulated ECCD with broad deposition
narrow deposition W>2d: - IECCD counts for helical CD
- full stabilisation with dc ECCD of (3,2) and (2,1) NTMs
- no advantage of phased ECCD
broad deposition W<2d:
- mimics ITER Wmarg~*
- IECCD/d2 counts for dc ECCD
- only partial dc stabilization
- required current increases significantly ⇒ modulated ECCD required
(at mode frequency / O-point injection)
Zohm EX/4-1RbYu TH/P3-13
17
184 X-point modulation
O-point modulation
tor
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 18
NTM stabilization: Modulated ECCD with broad deposition
Confinement improvement
j~IECCD/dW<2dITER
W>2d
O-point modulation
X-point modulation
Zohm EX/4-1Rb
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 19
High-Z wall and divertor in ITER / DEMO
pro: - tritium co-deposition with carbon - erosion of low-Z material - neutron bombardment destructs graphite
con: - central radiation losses sets limit cW< some 10-5
ITER DEMO
Dux EX/3-3RaSputtering source mainly from LFS limiters
- CX neutrals Te(edge)
- fast ions from NBI: depends on injection geometry
antenna limiters with ICRH: 60-90% of W influx - sheath rectified E-fields accelerate impurities- drastic enhancement of all sources during ELMs
Impurity transport- H-mode barrier ELM frequency control by pellet injection- neoclassical inward pinch- anomalous outward impurity transport enhanced by central heating (ICRH, ECRH) 0 0.1 0.2
1
10
100
pea
kin
g o
f c W
PECRH/Ptot
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 20
W wall: Long term evolution of W concentration
- wide distribution depending on plasma conditions:
increase with W coverage, saturation of mean value around 10-5
- reduced cW at relevant central heating power and higher densities (ITER!)
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 21
W wall: Indications for transitions to W device
reduction of C plasma content
(standard H-mode discharge)
Migration / transport model
- slow evolution due to strong C recycling
- C ‚leaking‘ out of divertor important
11019 atoms/s
remaining strong net erosion zone
Noble gas retention / release:Schmid EX/3-3Rb
Dux EX/3-3Ra
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 22
Improved H-mode: Characterization of „advanced scenarios
Reversed shear, ITB discharges: hollow current profile
high NH/q952>0.25 only transient
• control of pressure and current delicate • high bootstrap fraction > 60% ss• transport bifurcation
0
1
2
3
4
5
0 0.5 1r/a
strong
weak
q
Standard H-mode
~ zero shear
Reversedshear
Zero shear, ‘hybrid’ discharges: elevated q(0) above 1 desirable
stationary with NH/q952 up to 0.4
• high -limit close to no wall limit• substantial bootstrap fraction 50%• no bifurcation, smooth evolution
r/a 1
pla
sm
a p
ress
ure
0 0.5
Standard H- mode
~zero shear
Reversed shear
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 23
Improved H-mode: Performance and operational range
N = 2-3.3 and H98(y,2) =1-1.5
N above 3 achievable at q95=3-5
operating at ITER collisionality and at densities close to Greenwald stationary on several current diffusion times
similar correlation of density peaking to *
Sips EX/1-1, Weisen EX/8-4
DEMO
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 24
heat transport given by TEM/ITG turb.
- stiff temperature profile
- plasma energy connected with pedestal pressure (pedestal energy) confinement improvement weakly correl. with more peaked density profiles
pedestal top pressure enhanced
- increases stronger than Padd0.3
- predominantly Te,i rise
due to broader barrier width
- pbarrierconst.
Improved H-mode: Confinement
Suttrop EX/8-5, Maggi IT/P1-6,
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 25
Improved H-mode: Influence of q-profile
Scenarios with limiter /divertor ramp-up, early / late heating: effect on q profile
H98(y,2)=1.5, N=2.9
q954
H98(y,2)=1.2, N=2.3
q954
Stober EX/P1-7
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 26
different MHD behaviour: both clamp the current profile
slightly peaked current profile flat central current profile
influence on transport: - theory tells us R/LTi~s/q
- both quantities up to 25% enhanced for flat q-profile
- in agreement with threshold from GS2 (max=ExB)
edge pressure increased in case with flatter q-profile
Improved H-mode: Influence of q-profile
sawteeth
toroidalmodenumber n
freq
uenc
y (k
Hz)
time (s)
Stober EX/P1-7
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 27
Improved H-mode:(3,2) NTM suppression with ECCD
q95=2.9
N2.6
H98(y,2)1.2
dc, W/(2d)=0.6
- at low q95<3.5 large (3,2) NTM can develop strong impact on confinement- after stabilization transition to fishbone activity enhanced performance
Sips EX/1-1Zohm EX/4-1Rb
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 28
Substantial progress for the benefit of ITER was achieved.
AUG focuses on integrated ITER scenarios and performance beyond reference
Understanding of anomalous transport and turbulence (TEM,ITG) proceeds: ITER: peaked density profiles and benign high-Z accumulation to be expected
Fast ions: - losses caused by MHD and anomalous diffussion important
- off-axis NBCD above a certain turbulence level questionable
Modulated ECCD needed for NTM stabilization of ITER reference scenario
ELM (pacemaking) and disruption mitigation (gas injection) schemes evolve
high-Z walls compatible with tokamak operation modes - impurity sputtering source by ICRF accelerated impurities critical - accumulation control by ELMs and central heating (-particles) afforded
Improved H-mode / Hybrid scenario guides ITER beyond reference scenario
- ITER parameter range achieved (q95, *, ne/nGW)
at H98(y,2)=1.1-1.5 and N=2.5-3.5
- Q and prolonged pulse length at full current (q95=3)
- Q=10 and 1 h pulses at reduced current (q954)
- heating power of 73 MW may not be sufficient to achieve N3 for IPB98(y,2)
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 29
Main aim is to establish the physics base for ITER (and DEMO): - consolidation of the 'standard' H-mode scenario - exploration of ‚advanced' modes beyond standard scenario
Understanding of physics elements
- transport Angioni EX/8-5Rb, Conway EX/2-1, Jenko EX/8-5Ra, Weisen EX/8-4
- fast particles and NBCD Günter EX/6-1, McCarthy TH/P3-7
- H-mode edge and ELM tailoring
- disruption mitigation Pautasso EX/P8-7
- MHD control with ECCD Zohm EX/4-1Rb, Yu TH/P3-13, Merkel TH/P3-8
- tungsten wall and divertor Dux EX/3-3Ra, Schmid EX/3-3Rb
Integration into improved scenario beyond reference - Improved H-mode (Hybrid scenario)
Pereverzev FT/P5-23
Sips EX/1-1, Suttrop EX/8-5,Stober EX/P1-7, Maggi IT/P1-6,
Neuhauser EX/P8-2, Chankin TH/P6-15, Scott TH/1-1
AUG contributions to this conference
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 30
Technical incident with EZ4 at 27.04.06
flywheel generator EZ4 damaged
construction 1986,power 220 MVA,total weight ca. 160 tnumber of pulses est. 75.100,operated for est. 7.900 h
- eperimental campaign terminated- extent of damage: overhauling of generator rotor, new generator stator- operation in 2007 with EZ2 & 3 with only limited restrictions:
60% of all pulses possible with reduced coil voltages- full W machine will start with limited wall loads and discharge parameters
- in medium-term the full power/energy supply is needed for all relevant ITER work
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 31
ASDEX Upgrade, JETand ITER: a stepladder
similarity to ITER in coil system and divertor configuration - similar in geometrical configuration (linear dimensions scale 1:2:4) - different in size and therefore in dimensionless parameter * similarity in cross-section - size scaling and extrapolation to ITER
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 32
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 60% 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
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 33
Integrated evaluation of core and edge data:- state-of-art core diagnostic suite - multi-system, good resolution SOL & divertor diagnosticsNew or extended diagnostics:
Doppler reflectometry edge Ti and impurity densities from Li beam ultrafast (ns) Thomson digitisation for filament detection fast ion loss detector (new FILD at fixed positions) fast pellet observation (KFKI, Budapest) combined Langmuir and magnetic probes
Diagnostics under development collective TS at 105 GHz (Risø) distribution of fast ions; radiation level? collective TS at 140 GHz (Nizhny Novgorod / WTZ) magnetic field direction extension of reflectometry bands (Q band, IST Lisboa) SXR crystal spectrometer (Moscow, ITER) tangential edge CXRS system (NBI source 3 as radial CXRS, MSE) fast ELM resolving camera SXR (48 out of 148 lines of sight)
Enhancement of equilibrium reconstruction (CLISTE, FPJ)
Diagnostic extensions 2005/ 2006
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 34
Understanding of anomalous transport predictions
Flattening of density profile with increasing collisionality: AUG, JET, TCV:- transition from dominant TEM to ITG turbulence
- decrease of Te/Ti supports (heat pulse studies)
- gyrofluid model GLF23 agrees, nonlinear gyrokinetik GS2 results disagree
Strong link between ion heat and momentum transport
- colinearity between Ti and vtor
- strong correlation between and i-i,neo: ratio decreases across radius
No anomalous central impurity accumulation with central auxiliary heating- quasi-linear estimates with GS2 - impurity outward pinch driven by ITG turbulence under experimental conditions- -heating in ITER will do the job
Robust negative well of Er at plasma edge (Doppler reflectometry)
- negative well coincides with steep H-mode barrier pressure gradient
- Er shear enhanced as well
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 35
Transport: Er transitions at plasma edge
negative Er well increases
with confinement improvement
- coincides with H-mode barrier gradient
- Doppler reflectometry
Er shear enhanced as well
- 2 channel Doppler at fixed f ~ 2GHz
- negative shear at pedestal increases with confinement
- shear width 5cm
Conway EX/2-1
H98(y,2)
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 36
- FILD signal caused by DTM- response time depends on origin- orbit drifts and slowing down determine delay
beamswitch-off
beamswitch-off
4 ms
- Fast Ion Loss Detector (FILD) with bandwidth of 1 MHz
- frequency / phase correlations of fast ions with TAEs (from ICRH beatwaves)
- FILD spectrogram shows fast particle losses correlated with
low frequency MHD activity: NTMs, double tearing modes, ELMs
Fast particle interactions with large scale instabilities
Unexpected broadening of NBI driven currents:- energetic particle diffusion driven by small-scale turbulence (gyrokinetic code)
- redistribution of injected ions with Dfast0.5 m2/s
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 37
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
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 38
NTM stabilization: Influence of ECCD deposition width d
ITER: - threshold reduces with pol
AUG: - frequently interrupted NTM (FIR) allows higher ´s
- ECCD with helical current within the island to compensate the
missing BS current: jECCD>jBS
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 39
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
W/(2d)= 1.2
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 40
Improved H-mode: Scenario development
early versus late heating:
Te,i(0)4 keV
q954.8
ramp-up indivertor configuration
Stober EX/P1-7
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 41
NI
Improved H-mode: Scenario development
early versus late heating: performance increase
Te,i(0)4.5 keV
Te,i(0)5.2 keV
q954.8
N and H98(y,2) differences disappear at higher heating powers
ramp-up indivertor configuration
Stober EX/P1-7
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 42
heat transport given by TEM/ITG turbulence
- stiff temperature profile
- plasma energy connected with pedestal pressure (pedestal energy) confinement improvement weakly correlated with more peaked density profiles
- flatter density profiles anyway due to central heating (impurity accumulation!)
Improved H-mode: Confinement
Suttrop EX/8-5
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 43
Scenario development for ‚Improved H-Mode‘
early versus late heating
pol
pol
Reich, Stober
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 44
Improved H-mode: predictions for ITER
q95, N as in AUG, <n>/nGW=0.85, Te=Ti Pfus
Extrapolation to ITER using AUG kinetic profile shapes and IPB98(y,2) scaling
Ip=11.8 MA
q95=3.8
Paux=52 MW
Q=11.4
Improved H-modeIp=14.2 MA. q95=3.2
Paux=0
Q
Ip=9.7 MA
q95=4.6
Paux=55 MW
Q=6.5
standard H-modeIp=14.7 MA, q95=3.1
Paux=78 MW
Q=8
0
200
400
600
800
1000
1200
10 11 12 13 14 15Ip- ITER (MA)
open symbols Paux > 73 MW
closed symbols Paux ≤ 73 MW
ITER15 MA N,th 2.0
N,th = 2.5-3
Pfu
s (M
W)
Sips EX/1-1
Paux, Q
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 45
Test of W VPS coatings for divertor strike-points
200µm W VPS coatings
on graphite with adjusted
thermal expansion:
(Plansee, Sulzer Metco)
screening:
4 – 23 MW/m² cyclic loading:
10.8 MW/m², 3.5 s,
> 100 pulses
coatings are qualified for use in the lower divertor
0 2 4 6 81000
1500
2000
2500
16.2 MW/m²
6.5 MW/m²10.8 MW/m²
4.2 MW/m²
23.5 MW/m²
density 95% bulk W90% bulk W
pulse length (s)
Tsu
rf (
°C)
heat load tests in ion-beam facility GLADISH. Greuner
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 46
Scenario development for ‚Improved H-Mode‘ (Hybrid mode)
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 47
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
Development of ‚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
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 48
ECRF system: summary and outlook
• successful long pulse tests in factory test stand• long pulse tests at IPP hampered by load performance: few 10s pulses achieved up to 600kW at 105GHz and 800kW/140GHz• frequency drift during a gyrotron pulse within the limit for future double disc window application at intermediate frequencies (max. 150 MHz at 140 GHz)
• failure of vacuum conditions in the magnet lead to freezing of gyrotron cooling circuits;
cavity deformation prevented further operation of the gyrotron
measures for continuous, temperature controlled water circulation envisaged
• gyrotron Odissey-1 to be returned to GYCOM for repair• gyrotron Odissey-2 was successfully tested at GYCOM
planned installation as 2f gyrotron in coming weeks• after repair, Odissey-1 will be equipped with double disc window
planned operation as multi-frequency gyrotron end of the year
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 49
AUG enhancements: fast steerable ECRF launchers
ECRH launching mirrors in sector 5
launcher mirrors: W / Cu - coated graphite
Fast poloidal steering testedduring ASDEX shots withB=-2.18T, Ip=800kA:
a poloidal angle variationof 10° in 100 msec has been achieved
D. Wagner
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 50
Future AUG hardware extensions
● Internal coils - besides RWM control many other applications (f=1/10 kHz); 2007-9 - compatibility w. RWM control; - compatibility with heating systems - diagnostic access (YAG,...); - relevant diagnostic development
● ICRH antenna fitting to shell installation befor shell mounting ? LHCD 2008-10 5 MW at 3.7 GHz; 200 kA off-axis CD hardware and manpower from Associations needed
● Stabilising shell 2009-10
21st IAEA 2006, Chengdu, China, 17 Oct .2006 O. Gruber 51
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 hardware extensions