Transcript Overview of the H-1NF National Facility

H-1NF: the National Plasma
Fusion Research Facility
Boyd Blackwell* on behalf of the H-1 team* and the
Australian ITER forum
*Plasma Research Laboratory, Research School of
Physical Science and Engineering
College of Science, Australian National University
Blackwell, Australian ITER Workshop, 10/2006
H-1NF National Plasma Fusion
Research Facility
A Major National Research Facility established in 1997 by the
Commonwealth of Australia and the Australian National University
Mission:
• Detailed understanding of the behaviour of magnetically confined hot
plasma in the HELIAC configuration
• Development of advanced plasma measurement systems
• Fundamental studies including turbulence and transport in plasma
• Contribute to global research effort, maintain Australian presence in
the field of plasma fusion power
Contract extended until 2010: limited operational funding
The facility is available to Australian researchers through the AINSE1 and internationally
through collaboration with Plasma Research Laboratory, ANU.
1) Australian
Institute of Nuclear Science and Engineering
International collaboration played an important role in the
success of H-1 in obtaining facility funding
Blackwell, Australian ITER Workshop, 10/2006
H-1 Heliac: Parameters
3 period heliac: 1992
Major radius
1m
Minor radius
0.1-0.2m
Vacuum chamber 33m2 excellent access
Aspect ratio
5+
toroidal
Magnetic Field
1 Tesla (0.2 DC)
Heating Power
0.2MW 28 GHz ECH
0.3MW 6-25MHz ICH
Parameters:
n
T

Blackwell, Australian ITER Workshop, 10/2006
achieved to date::expected
3e18 :: 1e19
~100eV(Te)::500eV(Te)
0.1 :: 0.5%
Blackwell, Australian ITER Workshop, 10/2006
H-1 Vacuum Opening
Blackwell, Australian ITER Workshop, 10/2006
H-1NF Photo
Blackwell, Australian ITER Workshop, 10/2006
H-1 Configuration Map
• Original heliac:
limited configuration range.
• “flexible heliac” :
helical winding, with
helicity matching the plasma,
 2:1 range of iota
• H-1NF can control 2 out of 3 of
transform ()
magnetic well and
shear 
Blackwell, Australian ITER Workshop, 10/2006
E-Beam mapping
(wire tomography)
Rotating wire array
• 64 Mo wires (200um)
• 90 - 1440 angles
High accuracy (0.5mm)
Moderate image quality
Always available
Excellent agreement with computation
Blackwell, Australian ITER Workshop, 10/2006
B.D.Blackwell, J. Harris, T.A.
Santhosh Kumar, J.Howard
H-1 Remote control/Automatic scans
Four PLCS
Cooling, vacuum and
sequence control
Generator and heating power
control
H-1 Sequencer
Blackwell, Australian ITER Workshop, 10/2006
H-1 Remote data access
MDSPlus
IDL
RFX JScope
VNC
Blackwell, Australian ITER Workshop, 10/2006
H-1NF Data: MDSPlus + MySQL
gas properties
id
1
2
8
18
name
hydrogen
helium
oxygen
argon
gauge fact
2.2
5.5
0.99
0.78
flowfact
2.9
0.72
8.0
8.0
Machine
and human
generated
data tables
Summary Database: one entry per shot - machine generated ~100 columns
Id
9001
9002
9003
9004
9005
…..
Shot
45001
45002
45003
45004
45005
….
iring
6500
6500
6600
6700
6800
Gas
He
He
H/He
H/He
H/He
flow_2
0.0
2.0
0.5
0.5
0.5
rf_power
59.1
57.4
59.4
55.1
61.7
p_iong
1.1e-6
2.5e-6
1.1e-6
1.1e-6
1.2e-6
ne_18
1.18
1.51
1.61
1.63
1.69
p_iong
1.1e-6
1.2e-6
1.1e-6
1.1e-6
1.2e-6
lenth
.09
.091
.09
.09
.091
Comment
Test new MOSS camera
Test new MOSS camera
Test new MOSS camera
Test new MOSS camera
Test new MOSS camera
Log Entry Database: many entries per shot, 21 columns
topics
id
topic
description
1 operations
currents, timing
2 RF
RF heating
3 ECH
ECH system
4 MHD
equilibrium
5 MOSS
cameras, wheel
6 probes
LP, TMT,
create table topics (
id int unique auto_increment,
topic enum('shotnote',
'unknown','operations',
'config','datasys','RF','ECH
',
mySQL
database server
php web
interface
Graphic and
textual queries
Blackwell, Australian ITER Workshop, 10/2006
Id
5001
5002
Shot
45001
45001
5003
5004
45001
45001
5005
…..
45002
….
topic
datasys
impuriti
es
shotnote
MOSS
shotnote
precis
Ni impurity
increase flow to 1.5
modulation voltage
too low
He flow 2.0
Owner
camac
bdb112
cam112
cam112
cam112
Comment
Disk full error
Possible line at
4047
script
need to modify
analysis
fact=2.5 &
anal_moss,foo,fact
Com
plot_ccd_spectrum, sel28
nee
ana
ICRF and ECH Plasma
ICRF Heating:
Microwave Source:
•B=0.5Tesla,  = CH
(f~7Mhz)
(Kyoto-NIFS-ANU collab.)
•Large variation in ne
with iota

28 GHz gyrotron

230 kW ~ 40ms
Backward Wave
Oscillator
Scanning Interferometer
(Howard,
Oliver)
Blackwell, Australian ITER Workshop, 10/2006
D. Pretty, J. Harris
Configuration scan: Magnetic Fluctuations
ICRF plasma
configuration scan
5/
4/
4
7/
3
5
Mode spectrum changes
as resonances enter
plasma
No simple explanation
for “gap”
left side corresponds to
zero shear at resonance
Gap not obvious in ECH
Blackwell, Australian ITER Workshop, 10/2006
gap
5/
4
4/
3
7/
5
Large Device Physics on H-1
Confinement Transitions,
Turbulence (Shats, 1996--)
D3D tokamak
– H-mode 1996
– Zonal Flows 2001
– Spectral condensation of
turbulence 2005
Magnetic Island Studies
– H-1 has flexible, controlled and verified geometry
– Create islands in desired locations (shear, transform)
– Langmuir probes can map in detail
Alfvén Eigenmodes
• (over)
Blackwell, Australian ITER Workshop, 10/2006
H-1
Magnetic fluctuations
approach high temperature conditions:
•
•
•
•
•
H, He, D; B ~ 0.5T;
ne ~ 1e18; Te<50eV
i,e << a,
mfp >> conn
spectrum in excess of 100kHz
mode numbers not yet accurately resolved,
but appear low: m ~ 1- 8, n > 0
b/B ~ 2e-5
both broad-band and coherent/harmonic
nature
abrupt changes in spectrum for no
apparent reason
Blackwell, Australian ITER Workshop, 10/2006
Poloidal mode number measurements
phase
Expected for
m =2
magnitude
“bean-shaped” 20 coil Mirnov array
• Phase vs poloidal angle is not
simple
–
–
Magnetic coordinates
External to plasma
• Propagation effects
• Large amplitude variation
Significant interpretation problem in
advanced confinement
configurations
Blackwell, Australian ITER Workshop, 10/2006
coil number (poloidal angle )
Identification with Alfvén Eigenmodes
•
•
•
•
•
Coherent mode near iota = 1.4, 2630kHz, Alfvénic scaling with ne
m number resolved by bean array of
Mirnov coils to be 2 or 3.
Cylindrical theory predicts two
possible GAEs at m=2, and m=3
phase
Scaling in ne and k|| (iota)
Many other examples of Alfvénic
scaling
Two possible GAEs ~20-25kHz
Blackwell, Australian ITER Workshop, 10/2006
Planned : Exploration of EPM Physics
(also with M. J. Hole, L. C. Appel)
• Passive Alfvén eigenmodes: Synergistic theory/experiment
study of wave drive, and effect on confinement.
• Experiment: Multiple sources of non-thermal particle
populations: RF heating, ECH, molecular beam and gas puff.
• Diagnosis. Essential for EPM studies. Some include
- ne : tomographic interferometer. (10kHz, ~2cm resol.)
-Ti,vi : “coherence imaging” optical system
- Bext : 2 x 20 coil “Mirnov” arrays  (m,n) up to 200 kHz
- Bext : CAE measurements, f< 5MHz OMAHA coils (UKAEA)
- Bint : sensitive mm-wave homodyne polarimeter/interferometer.
•Active Excitation :
– Compressional Alfvén antenna ~ 100’s kW.
– Selective frequency tuning for electron or ions (4-26 MHz)
Blackwell, Australian ITER Workshop, 10/2006
200 kW, 28GHz gyrotron
D. Pretty
“Data Mining” handles large quantities of data
• 4 Gigasamples of data
– 128 times
– 128 frequencies
– 2C20 coil combinations
– 100 shots
• Data mining allows sub
sampling, exploring and rule
extraction
• Initial work with “Weka”
java and Gabor transforms
for time freq analysis
Huge data sets are a common
problem in complex
geometries often associated
with advanced confinement
configurations
Blackwell, Australian ITER Workshop, 10/2006
D. Pretty
Mode Decomposition by SVD and Clustering
•
4 Gigasamples of data
– 128 times
– 128 frequencies
– 2C20 coil combinations
– 100 shots
•
Initial decomposition by SVD
 ~10-20 eigenvalues
• Remove low coherence and
low amplitude
• Then group eigenvalues by
spectral similarity into
fluctuation structures
• Reconstruct structures
to obtain phase difference at
spectral maximum
• Cluster structures according
to phase differences (m
numbers)
 reduces to 7-9 clusters for an
iota scan
Blackwell, Australian ITER Workshop, 10/2006
D. Pretty
Mode Decomposition by SVD and Clustering
• 4 Gigasamples of data
– 128 times
– 128 frequencies
– 2C20 coil combinations
– 100 shots
…….
• Cluster structures according
to phase differences (m
numbers)
 reduces to 7-9 clusters for an
iota scan
Grouping by clustering
potentially more powerful
than by mode number
– Recognises mixtures of
mode numbers caused by
toroidal effects etc
– Does not depend critically
on knowledge of the correct
magnetic theta coordinate
Blackwell, Australian ITER Workshop, 10/2006
m=0,3,5
m=2
m=3
m=1
m=0
m=1,2,3
m=4
m=3,1
Diagnostic Collaborations
e.g. Helium Diagnostic Beam
• Purpose – to locally
measure Te and ne
(Sasaki et al.)
• Very narrow (15mm) very
brief (200us) burst of He
• Allows point localised
measurements
The University
of Sydney
Pulsed jet
Skimmer
J. Howard
Thurs PM
D. Andruczyk, S. Collis
Blackwell, Australian ITER Workshop, 10/2006
Summary
• Configurational effects demonstrated:
– particle confinement effects, magnetic fluctuation spectra
– Poloidal mode numbers identification with Mirnov array, Toroidal
soon
– Alfvénic modes observed
– New campaign of surface mapping provides further insight into
configuration scan
– Data mining – unsupervised reduction into physically significant
clusters
• New Diagnostics (J. Howard Thurs PM)
• Possible Contributions to ITER Effort
– Better understanding of plasma phenomena
• Confinement Transitions
• Alfvén Eigenmodes
• Magnetic Islands
– Test Bed for Advanced Diagnostic Development
– H1 plasma is similar to reactor edge plasma
Blackwell, Australian ITER Workshop, 10/2006
Future
• New diagnostics
– LIF E-field measurements
– Triple probe array (T3)
– Soft X-ray arrays, one interchangeable foil (University of Canberra)
•Dynamics - modulation of n and T, gas puffing
– possibility of high field confinement transitions with increased power
•Plasma Generation: RF and ECH: improve Te and pulse length
– 200kW ECH, 250kW RF, improved discharge cleaning
•Progression to high temperature: e.g.
– Turbulence/Flow studies via correlation spectroscopy, microwave
scattering
– Radial force balance information via coherence imaging
spectroscopy
– Extensive Configuration Studies
• three control windings  iota, well and shear
• higher power for stability studies approaching  ~ 0.5%
• interchange, ballooning modes.
Blackwell, Australian ITER Workshop, 10/2006