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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