Talk EX8 6

Information about Talk EX8 6

Published on March 12, 2008

Author: Altoro

Source: authorstream.com

Content

Slide1:  Confinement and Local Transport in the National Spherical Torus Experiment (NSTX) Stanley M. Kaye1, M.G. Bell1, R.E. Bell1, C. W. Domier2, W. Horton3, J. Kim3, B.P. LeBlanc1, F. Levinton4,N.C. Luhmann2, R. Maingi5, E. Mazzucato1, J.E. Menard1, D.R. Mikkelsen1, H. Park1, G. Rewoldt1, S.A. Sabbagh6, D. Smith1, D. Stutman7, K. Tritz7, W. Wang1, H. Yuh4 21st IAEA/Fusion 2006 Meeting Oct 16 – 21, 2006 Chengdu, China 1 PPPL, Princeton University, Princeton, NJ, USA 08543 2 University of California, Davis, CA, USA 95616 3 IFS, University of Texas, Austin, TX, USA 78712 4 Nova Photonics Inc., Princeton, NJ, USA, 08540 5 ORNL, Oak Ridge, TN, USA 37831 6 Dept. of Applied Physics, Columbia University, NYC, NY, USA 10027 7 The Johns Hopkins University, Baltimore MD 21218 Culham Sci Ctr U St. Andrews York U Chubu U Fukui U Hiroshima U Hyogo U Kyoto U Kyushu U Kyushu Tokai U NIFS Niigata U U Tokyo JAERI Hebrew U Ioffe Inst RRC Kurchatov Inst TRINITI KBSI KAIST ENEA, Frascati CEA, Cadarache IPP, Jülich IPP, Garching ASCR, Czech Rep U Quebec College W&M Colorado Sch Mines Columbia U Comp-X General Atomics INEL Johns Hopkins U LANL LLNL Lodestar MIT Nova Photonics New York U Old Dominion U ORNL PPPL PSI Princeton U SNL Think Tank, Inc. UC Davis UC Irvine UCLA UCSD U Colorado U Maryland U Rochester U Washington U Wisconsin NSTX Addresses Transport & Turbulence Issues Critical to Both Basic Toroidal Confinement and Future Devices:  NSTX Addresses Transport & Turbulence Issues Critical to Both Basic Toroidal Confinement and Future Devices NSTX offers a novel view into plasma T&T properties NSTX operates in a unique part of dimensionless parameter space: R/a, bT, (r*, n*) Dominant electron heating with NBI: relevant to a-heating in ITER Major Radius R0 0.85 m Aspect Ratio A 1.3 Elongation k 2.8 Triangularity d 0.8 Plasma Current Ip 1.5 MA Toroidal Field BT 0.55 T Pulse Length 1.5 s NB Heating (100 keV) 7 MW bT,tot up to 40% Excellent laboratory in which to study electron transport: electron transport anomalous, ions close to neoclassical Large range of bT spanning e-s to e-m turbulence regimes Strong rotational shear that can influence transport Localized electron-scale turbulence measurable (re ~ 0.1 mm) This Presentation Will Focus on Confinement & Transport Trends in NSTX and Their Underlying Processes:  This Presentation Will Focus on Confinement & Transport Trends in NSTX and Their Underlying Processes Major accomplishments Key confinement and transport dependences established (BT, Ip, b, n*, q(r),…) High priority ITPA tasks have been addressed Dimensionless parameter scans in bT, ne* Established more accurate e (=a/R) scaling with NSTX (& MAST) data included in the ITPA database t98y2~Ip0.93 BT0.15 ne0.41 P-0.69 R1.97 e0.58… tnew~Ip0.73 BT0.36 ne0.39 P-0.62 R2.14 e1.03 (Kaye et al., PPCF 48 [2006] A429) Localized turbulence characteristics being assessed across wide range of k (upper ITG/TEM to ETG) Theory/simulations have indicated ETG modes could be important in controlling electron transport Dimensionless Parameter Scans Have Addressed High-Priority ITPA Issues:  Dimensionless Parameter Scans Have Addressed High-Priority ITPA Issues b-scan at fixed q, BT - b-dependence important to ITER advanced scenarios (Bt98y2~b-0.9) - Factor of 2-2.5 variation in bT - Degradation of tE with b weak on NSTX 20% variation in re, ne* ne*-scan at fixed q - Factor of >3 variation in ne* - Strong increase of confinement with decreasing collisionality k=2.1 d=0.6 Dedicated H-mode Confinement Scaling Experiments Have Isolated the BT and Ip Dependences:  Dedicated H-mode Confinement Scaling Experiments Have Isolated the BT and Ip Dependences Scans carried out at constant density, injected power (4 MW) 0.50 s 0.50 s Dedicated H-mode Confinement Scaling Experiments Have Revealed Some Surprises:  Dedicated H-mode Confinement Scaling Experiments Have Revealed Some Surprises Strong dependence of tE on BT tE,98y,2 ~ BT0.15 H98y,2 ~ 0.9 → 1.1 → 1.4 4 MW tE,98y,2 ~ Ip0.93 H98y,2 ~ 1.4 → 1.3 → 1.1 Weaker dependence on Ip tE~Ip1.3-1.5 at fixed q tE,98y,2~Ip1.1 at fixed q NSTX tE exhibits strong scaling at fixed q 4 MW Slide7:  Variation of Electron Transport Primarily Responsible for BT Scaling Broadening of Te & reduction in ce outside r/a=0.5 with increasing BT Ions near neoclassical Neoclassical Slide8:  Theory/Gyrokinetic Calculations Suggest ETG May Play an Important Role in Determining Electron Transport at Low BT Non-linear simulations indicate formation of radial streamers (up to 200re): FLR-modified fluid code [Horton et al., PoP 2005] Good agreement between experimental and theoretical saturated transport level at 0.35 T Experimental ce profile consistent with that predicted by e-m ETG theory [Horton et al., NF 2004] at 0.35 T Not at higher BT Kim, IFS ETG linearly unstable only at lowest BT - 0.35 T: R/LTe 20% above critical gradient - 0.45, 0.55 T: R/LTe 20-30% below critical gradient 0.35 T GS2 Slide9:  Ion Transport Primarily Governs Ip Scaling - Ions Near Neoclassical Level - ci,GTC-NEO (r/a=0.5-0.8) GTC-Neo neoclassical: includes finite banana width effects (non-local) Slide10:  Turbulence Measurements + Gyrokinetic Calculations Have Helped Identify Possible Sources of Transport Ion transport during H-phase is neoclassical Electron transport reduced, but remains anomalous Ion and electron transport change going from L- to H-modes - Localized measurement (axis to edge) - Excellent radial resolution (6 cm) Slide11:  Theory/Gyrokinetic Calculations Indicate Both ITG/TEM and ETG are Possible Candidates for Electron Transport GS2 calculations indicate lower linear growth rates at all wavenumbers during H- than during L-phase: ETG unstable Experimental ce profile consistent with that predicted by e-s ETG theory (Horton et al, Phys. Plasmas [2004]) Non-linear GTC results indicate ITG modes stable during H-phase; ci ~ neoclassical NSTX Plays a Key Role in Multi-Scale Transport & Turbulence Research:  NSTX Plays a Key Role in Multi-Scale Transport & Turbulence Research Confinement and transport trends found to differ from those at higher R/a Strong BT, weaker Ip scaling Electron transport variation primarily responsible for BT scaling Ions near neoclassical; primarily responsible for Ip scaling Understand the source of the difference in confinement trends at different R/a (low vs high-k turbulence dominant at different R/a, BT?) Data provided to ITPA H-mode database for R/a and bT scalings No degradation of BtE with bT Backup Vugraphs:  Backup Vugraphs Slide14:  New Diagnostic Capabilities Have Facilitated Progress in Understanding Transport Processes 12 channel MSE [NOVA Photonics] LRDFIT Reconstruction Rmag 51-point CHERS 20-point MPTS Tangential microwave scattering measures localized electron-scale turbulence kr=2 (upper ITG/TEM) to ~24 (ETG) cm-1 re ~0.01 cm Dr ~ 6 cm Dk ~ 1 cm-1 Can vary location of scattering volume (near Rmag to near edge) Important for equilibrium and microinstability calculations New Diagnostic Capabilities Have Facilitated Progress in Understanding Transport Processes:  New Diagnostic Capabilities Have Facilitated Progress in Understanding Transport Processes Tangential micorwave scattering measures localized electron-scale turbulence 12 channel MSE [NOVA Photonics] Important for equilibrium and microinstability calculations kr=2 (upper ITG/TEM) to ~24 (ETG) cm-1 re ~0.01 cm Dr ~ 6 cm Dk ~ 1 cm-1 Can vary location of scattering volume (near Rmag to near edge) Dimensionless Variable Scans Have Addressed High Priority ITPA Physics Issues (e, b - scaling):  Dimensionless Variable Scans Have Addressed High Priority ITPA Physics Issues (e, b - scaling) b-scan at fixed re, ne* - b-dependence important to ITER advanced scenarios (Bt98y2~b-0.9) - Degradation of tE with b weak on NSTX NSTX data used in conjunction with ITPA data to establish e (=a/R) scaling with more confidence ITER98PB(y,2) scaling does not represent low R/a data well t98y2~Ip0.93BT0.15ne0.41P-0.69R1.97e0.58… tnew~Ip0.73BT0.36ne0.39P-0.62R2.14e1.03 (Kaye et al., PPCF 48 [2006] A429) 2-2.5 variation in bT 20% variation in re, ne* Slide17:  Stronger Reversed Magnetic Shear Is Associated with Reduced Transport Weak vs Reverse-Shear L-mode Global non-linear GTC and GYRO simulations show that a pure ITG mode is unstable without ExB flow shear included TEM & ETG calculations underway Slide18:  Pellet Perturbations Are Being Used to Probe Relation of Critical Gradient Physics to q-Profile H-mode with monotonic q-profile exhibits stiff profile behavior → Te close to marginal stability Reversed magnetic shear L-mode responds to pellet perturbation over several ms Soft X-ray array diagnoses fast DTe R/LTe t=297→301 ms R/LTe t=440→444 ms Stutman, JHU

Related presentations


Other presentations created by Altoro

Robot Different Types
07. 01. 2008
0 views

Robot Different Types

guzman
18. 04. 2008
0 views

guzman

PublicFinancevsPubli cChoice
13. 04. 2008
0 views

PublicFinancevsPubli cChoice

2779JacobFrenkel
10. 04. 2008
0 views

2779JacobFrenkel

Chapter 02 Warming the Earth
07. 04. 2008
0 views

Chapter 02 Warming the Earth

ElectronicRetailersA ssociation9
27. 03. 2008
0 views

ElectronicRetailersA ssociation9

mining
26. 03. 2008
0 views

mining

Austria
21. 03. 2008
0 views

Austria

poc presentationv ny
28. 09. 2007
0 views

poc presentationv ny

PPT Jon Sigurdson
12. 10. 2007
0 views

PPT Jon Sigurdson

Workshop Wintersport
12. 10. 2007
0 views

Workshop Wintersport

2006 2007 Calender
06. 09. 2007
0 views

2006 2007 Calender

Protein for Athletes
06. 09. 2007
0 views

Protein for Athletes

a23
12. 09. 2007
0 views

a23

lecture 18 bread fermentation
04. 10. 2007
0 views

lecture 18 bread fermentation

ustman
09. 11. 2007
0 views

ustman

Slavery
11. 12. 2007
0 views

Slavery

The Model Hockey Program
06. 09. 2007
0 views

The Model Hockey Program

WAWF Deployment Review
07. 11. 2007
0 views

WAWF Deployment Review

soybeans2007
07. 11. 2007
0 views

soybeans2007

Association HEP Training
06. 09. 2007
0 views

Association HEP Training

Portion Distortion
12. 09. 2007
0 views

Portion Distortion

compositae2006r
07. 12. 2007
0 views

compositae2006r

The Cold War and Domino Theory
19. 12. 2007
0 views

The Cold War and Domino Theory

nelson NATO
25. 12. 2007
0 views

nelson NATO

Fri 04 Killar
29. 12. 2007
0 views

Fri 04 Killar

Oslo 1
02. 01. 2008
0 views

Oslo 1

fruit diseases05
04. 01. 2008
0 views

fruit diseases05

HARRY S TRUMAN
28. 12. 2007
0 views

HARRY S TRUMAN

hayek45
12. 09. 2007
0 views

hayek45

ETC 2004 10 25
06. 09. 2007
0 views

ETC 2004 10 25

CT303 NetworkingDevices
28. 12. 2007
0 views

CT303 NetworkingDevices

IDIS
10. 12. 2007
0 views

IDIS

lect04Slides
14. 12. 2007
0 views

lect04Slides

missions
24. 02. 2008
0 views

missions

360
12. 09. 2007
0 views

360

3 4apr07 SDD Chief
29. 11. 2007
0 views

3 4apr07 SDD Chief

LoD
24. 12. 2007
0 views

LoD

Roch Stuart
24. 02. 2008
0 views

Roch Stuart

sp10002 3
19. 02. 2008
0 views

sp10002 3

FY2006TourismMediaPl an
10. 10. 2007
0 views

FY2006TourismMediaPl an

Thompson
12. 09. 2007
0 views

Thompson

SMI Innov
17. 06. 2007
0 views

SMI Innov

Salvo Presentation
17. 06. 2007
0 views

Salvo Presentation

SALTO Inclusion 2005
17. 06. 2007
0 views

SALTO Inclusion 2005

athletics
17. 06. 2007
0 views

athletics

JohnBare 11sept07
04. 12. 2007
0 views

JohnBare 11sept07

pizza talk 2006
12. 09. 2007
0 views

pizza talk 2006

Selectividad2007
17. 06. 2007
0 views

Selectividad2007

Phil Borgeaud final
06. 09. 2007
0 views

Phil Borgeaud final

Chelsie and Samantha
02. 11. 2007
0 views

Chelsie and Samantha

PLVol1
26. 11. 2007
0 views

PLVol1

ACHA Rules of Emphasis 8 12 06
06. 09. 2007
0 views

ACHA Rules of Emphasis 8 12 06

Renuka Ramnath
12. 09. 2007
0 views

Renuka Ramnath

Overview of Japan Steel Industry
09. 10. 2007
0 views

Overview of Japan Steel Industry

the10mostbeautifulsu rahs
02. 10. 2007
0 views

the10mostbeautifulsu rahs

prez2
21. 11. 2007
0 views

prez2

PlanningMinorityComm unities
26. 02. 2008
0 views

PlanningMinorityComm unities

PPT for recruits 03 2
06. 09. 2007
0 views

PPT for recruits 03 2

siklejog2
17. 06. 2007
0 views

siklejog2

Amuse Promotional materials
12. 10. 2007
0 views

Amuse Promotional materials

GDSv15Training
03. 01. 2008
0 views

GDSv15Training