Weixing Ding University of California, Los Angeles,USA collaborators: D.L. Brower, W. Bergerson, D. Craig, D. Demers, G.Fiksel, D.J. Den Hartog, J. Reusch,

Slides:

Advertisements

Similar presentations

NSF Site Visit Madison, May 1-2, 2006 Magnetic Helicity Conservation and Transport R. Kulsrud and H. Ji for participants of the Center for Magnetic Self-organization.

Advertisements

Statistical Properties of Broadband Magnetic Turbulence in the Reversed Field Pinch John Sarff D. Craig, L. Frassinetti 1, L. Marrelli 1, P. Martin 1,

Experimental Measurements of Non- MHD Dynamo Effects Summarized by S.C. Prager.

Dynamo Effects in Laboratory Plasmas S.C. Prager University of Wisconsin October, 2003.

Self-consistent mean field forces in two-fluid models of turbulent plasmas C. C. Hegna University of Wisconsin Madison, WI Hall Dynamo Get-together PPPL.

Magnetic Relaxation in MST S. Prager University of Wisconsin and CMSO.

Control of Magnetic Chaos & Self-Organization John Sarff for MST Group CMSO General Meeting Madison, WI August 4-6, 2004.

Plans for Dynamo Research Presented by F. Cattaneo, S. Prager.

Progress and Plans on Magnetic Reconnection for CMSO For NSF Site-Visit for CMSO May1-2, Experimental progress [M. Yamada] -Findings on two-fluid.

Ion Heating and Velocity Fluctuation Measurements in MST Sanjay Gangadhara, Darren Craig, David Ennis, Gennady Fiskel and the MST team University of Wisconsin-Madison.

Self-consistent mean field forces in two-fluid models of turbulent plasmas C. C. Hegna University of Wisconsin Madison, WI CMSO Meeting Madison, WI August.

Experimental Tests of Two-Fluid Relaxation D. Craig and MST Team University of Wisconsin – Madison General Meeting of the Center for Magnetic Self-Organization.

Dynamo and Magnetic Helicity Flux Hantao Ji CMSO & PPPL CMSO General Meeting Princeton, October 5-7, 2005 Contributors: Eric Blackman (Rochester) Stewart.

Comparing classical and lab plasma dynamos S. Prager University of Wisconsin useful discussions with D. Craig, H. Ji, J. Sarff, E. Zweibel.

Multiple reconnections and explosive events and in MST and solar flares Gennady Fiksel CMSO workshop, Princeton, NJ, Oct 5-8, 2005.

MHD Dynamos in the Lab and Dynamos Beyond MHD. The lab plasma dynamo does Generate current locally Increase toroidal magnetic flux Conserve magnetic helicity.

Anomalous Ion Heating Status and Research Plan

Some New Data From FRC Experiment on Relaxation For discussions at Hall-Dynamo and Related Physics meeting CMSO June 10-11, 2004 at PPPL Guo et al, PRL.

Charge-Exchange Spectroscopy at the University of Wisconsin-Madison Mark Nornberg Santhosh Kumar, Daniel Den Hartog Alexis Briesemeister 2012 ADAS Workshop.

The UW Plasma Physics Group Clint Sprott, Paul Terry, Ellen Zweibel, Stas Boldyrev, Dalton Schnack, Cary Forest, Stewart Prager Presented to Introductory.

Momentum Transport During Reconnection Events in the MST Reversed Field Pinch Alexey Kuritsyn In collaboration with A.F. Almagri, D.L. Brower, W.X. Ding,

SUGGESTED DIII-D RESEARCH FOCUS ON PEDESTAL/BOUNDARY PHYSICS Bill Stacey Georgia Tech Presented at DIII-D Planning Meeting

The Reversed Field Pinch: on the path to fusion energy S.C. Prager September, 2006 FPA Symposium.

Overview of Results in the MST Reversed-Field Pinch D. J. Den Hartog University of Wisconsin – Madison Center for Magnetic Self-Organization 20 October.

INTRODUCTION OF WAVE-PARTICLE RESONANCE IN TOKAMAKS J.Q. Dong Southwestern Institute of Physics Chengdu, China International School on Plasma Turbulence.

RFP Workshop, Stockholm 9-11 /10/ 2008 Numerical studies of particle transport mechanisms in RFX-mod low chaos regimes M.Gobbin, L.Marrelli, L.Carraro,

Plasma Dynamics Lab HIBP Abstract Measurements of the radial equilibrium potential profiles have been successfully obtained with a Heavy Ion Beam Probe.

Plasma Dynamics Lab HIBP Abstract Measurements of the radial equilibrium potential profiles have been successfully obtained with a Heavy Ion Beam Probe.

GTC Status: Physics Capabilities & Recent Applications Y. Xiao for GTC team UC Irvine.

HEAT TRANSPORT andCONFINEMENTin EXTRAP T2R L. Frassinetti, P.R. Brunsell, M. Cecconello, S. Menmuir and J.R. Drake.

1 / 12 Association EURATOM-CEA IAEA 20th Fusion Energy Conference presented by Ph. Ghendrih S. Benkadda, P. Beyer M. Bécoulet, G. Falchetto,

Non-collisional ion heating and Magnetic Turbulence in MST Abdulgader Almagri On behalf of MST Team RFP Workshop Padova, Italy April 2010.

MMFW Madison, Wisconsin 6 May 2011 D.J. Den Hartog, R. M. Magee, S.T.A. Kumar, V.V. Mirnov (University of Wisconsin–Madison) D. Craig (Wheaton College)

D. Borba 1 21 st IAEA Fusion Energy Conference, Chengdu China 21 st October 2006 Excitation of Alfvén eigenmodes with sub-Alfvénic neutral beam ions in.

Kinetic Effects on the Linear and Nonlinear Stability Properties of Field- Reversed Configurations E. V. Belova PPPL 2003 APS DPP Meeting, October 2003.

TH/7-2 Radial Localization of Alfven Eigenmodes and Zonal Field Generation Z. Lin University of California, Irvine Fusion Simulation Center, Peking University.

Challenging problems in kinetic simulation of turbulence and transport in tokamaks Yang Chen Center for Integrated Plasma Studies University of Colorado.

Excitation of ion temperature gradient and trapped electron modes in HL-2A tokamak The 3 th Annual Workshop on Fusion Simulation and Theory, Hefei, March.

Plasma Dynamics Lab HIBP E ~ 0 V/m in Locked Discharges Average potential ~ 580 V  ~ V less than in standard rotating plasmas Drop in potential.

CCFE is the fusion research arm of the United Kingdom Atomic Energy Authority Internal Transport Barriers and Improved Confinement in Tokamaks (Three possible.

Stability Properties of Field-Reversed Configurations (FRC) E. V. Belova PPPL 2003 International Sherwood Fusion Theory Conference Corpus Christi, TX,

1 Non-neutral Plasma Shock HU Xiwei （胡希伟）工 HU Xiwei （胡希伟） HE Yong （何勇） HE Yong （何勇） Hu Yemin （胡业民） Hu Yemin （胡业民） Huazhong University of Science and.

14 Oct. 2009, S. Masuzaki 1/18 Edge Heat Transport in the Helical Divertor Configuration in LHD S. Masuzaki, M. Kobayashi, T. Murase, T. Morisaki, N. Ohyabu,

DIII-D SHOT #87009 Observes a Plasma Disruption During Neutral Beam Heating At High Plasma Beta Callen et.al, Phys. Plasmas 6, 2963 (1999) Rapid loss of.

Investigation of fast ion mode spatial structure in NSTX N.A. Crocker, S. Kubota, W.A. Peebles (UCLA); E.D. Fredrickson, N.N. Gorelenkov, G.J. Kramer,

SLM 2/29/2000 WAH 13 Mar NBI Driven Neoclassical Effects W. A. Houlberg ORNL K.C. Shaing, J.D. Callen U. Wis-Madison NSTX Meeting 25 March 2002.

EXTENSIONS OF NEOCLASSICAL ROTATION THEORY & COMPARISON WITH EXPERIMENT W.M. Stacey 1 & C. Bae, Georgia Tech Wayne Solomon, Princeton TTF2013, Santa Rosa,

FEC 2006 Reduction of Neoclassical Transport and Observation of a Fast Electron Driven Instability with Quasisymmetry in HSX J.M. Canik 1, D.L. Brower.

Demonstration of tearing mode braking and locking due to eddy currents in a toroidal magnetic fusion device B.E. Chapman (University of Wisconsin, USA)

Magnetic Reconnection in Plasmas; a Celestial Phenomenon in the Laboratory J Egedal, W Fox, N Katz, A Le, M Porkolab, MIT, PSFC, Cambridge, MA.

Role of thermal instabilities and anomalous transport in the density limit M.Z.Tokar, F.A.Kelly, Y.Liang, X.Loozen Institut für Plasmaphysik, Forschungszentrum.

Non-linear MHD modelling of RMPs with toroidal rotation and resonant and non-resonant plasma braking. M.Becoulet G. Huysmans, E. Nardon Association Euratom-CEA,

21st IAEA Fusion Energy Conf. Chengdu, China, Oct.16-21, /17 Gyrokinetic Theory and Simulation of Zonal Flows and Turbulence in Helical Systems T.-H.

52nd Annual Meeting of the Division of Plasma Physics, November , 2010, Chicago, Illinois Non-symmetric components were intentionally added to the.

1) For equivalent ECRH power, off-axis heating results in lower stored energy and lower core temperature 2) Plasma flow is significantly reduced with off-axis.

Helically Symmetry Configuration Evidence for Alfvénic Fluctuations in Quasi-Helically Symmetric HSX Plasmas C. Deng and D.L. Brower, University of California,

Scaling experiments of perturbative impurity transport in NSTX D. Stutman, M. Finkenthal Johns Hopkins University J. Menard, E. Synakowski, B. Leblanc,R.

53rd Annual Meeting of the Division of Plasma Physics, November , 2010, Salt Lake City, Utah 5-pin Langmuir probe configured to measure the Reynolds.

53rd Annual Meeting of the Division of Plasma Physics, November , 2011, Salt Lake City, Utah When the total flow will move approximately along the.

Simulation of Turbulence in FTU M. Romanelli, M De Benedetti, A Thyagaraja* *UKAEA, Culham Sciance Centre, UK Associazione.

IAEA-TM 02/03/2005 1G. Falchetto DRFC, CEA-Cadarache Association EURATOM-CEA NON-LINEAR FLUID SIMULATIONS of THE EFFECT of ROTATION on ION HEAT TURBULENT.

Computational Astrophysics: Magnetic Fields and Charged Particle Dynamics 8-dec-2008.

Plan V. Rozhansky, E. Kaveeva St.Petersburg State Polytechnical University, , Polytechnicheskaya 29, St.Petersburg, Russia Poloidal and Toroidal.

Profiles of density fluctuations in frequency range of (20-110)kHz Core density fluctuations Parallel flow measured by CHERS Core Density Fluctuations.

NIMROD Simulations of a DIII-D Plasma Disruption S. Kruger, D. Schnack (SAIC) April 27, 2004 Sherwood Fusion Theory Meeting, Missoula, MT.

54th Annual Meeting of the Division of Plasma Physics, October 29 – November 2, 2012, Providence, Rhode Island 5-pin Langmuir probe measures floating potential.

Mechanisms for losses during Edge Localised modes (ELMs)

An overview of turbulent transport in tokamaks

Reduction of Neoclassical Transport and Observation of a Fast Electron Driven Instability with Quasisymmetry in HSX J.M. Canik1, D.L. Brower2, C. Deng2,

Huishan Cai, Jintao Cao, Ding Li

Presentation transcript:

Weixing Ding University of California, Los Angeles,USA collaborators: D.L. Brower, W. Bergerson, D. Craig, D. Demers, G.Fiksel, D.J. Den Hartog, J. Reusch, S. C. Prager, J. Sarff, T.Yates and MST team (Oct. 14, 2009 Princeton) Particle Transport due to Stochastic Magnetic Field in a High-Temperature Plasma

Introduction Free energy instabilities Fluctuations Particle (charge) Momentum Energy Transport  J // (r) Tearing

Electron Density Relaxation Due to Magnetic Field Perturbation Magnetic Field Fluctuations Driven by Tearing Instabilities in MST MST L.Zeng (UCLA) et al DIII-D by reflectometry Driven by I-coil externally in DIII-D DIII-D

MST Reversed-Field Pinch (RFP) is toroidal configuration with relatively weak toroidal magnetic field B T ( i.e., B T ~ B p ) Madison Symmetric Torus For plasma w/o current profile control R 0 = 1.5 m, a = 0.51 m, I p ~400 kA B T ~ 3-4 kG, n e ~ m -3,T e ~T i ~300eV  ~7%

Fluctuations and Transport in the MST Generation of magnetic flux (dynamo) Particle and energy transport Ion heating Momentum transport Magnetic reconnection events

Outline (1) Density Relaxation and particle transport during reconnection; (2) Measured magnetic fluctuation-induced particle flux accounts for particle transport; GOAL: Identify the role of stochastic magnetic field in particle transport during reconnection

Particle Diffusion Rate in a Stochastic Magnetic Field in MST Toroidal Angle /  r/a Puncture Plot of B Field in MST Magnetic diffusivity coefficient from field line tracing (Hudson and Gennady, 2006) Rechester & Rosenbluth (1978) derived a quasi-linear coefficient Harvey (1981) and Finn (1990) suggest particle diffusion rate D i ~ D m c s (or V i,th ) Plugging in MST parameters:  p ~ 1-2 ms (quasi-linear estimate) in ambient case  p ~ ms (experiment) during relaxation event

Measured Total Particle Flux during Reconnection r L Total particle flux surges to 1.5*10 21 m -2 s -1 during reconnection

Fluctuation-Induced Particle Flux Contributes to Total Flux Particle transport is determined by perpendicular momentum balance Particle transport arises from particle streaming along stochastic field lines total flux pinch electrostatic magnetic fluctuation

Pinch and electrostatic fluctuation-induced particle flux are negligible Lei, et al. PRL 2002 total flux pinch electrostatic magnetic fluctuation electrostatic

Magnetic Fluctuation-Induced Particle Flux Density-fluctuation dependent flux Velocity-fluctuation dependent flux

Measurement of Magnetic Fluctuation-Induced Particle Flux Laser Faraday rotation B  Laser Faraday rotation Laser interferometer ( ) Motion Stark effect CHERS, Mode Rotation, Ion Doppler Spectroscopy Not measured, inferred from quasi-neutrality 7 independent quantities are needed to determine electron and ion flux

FIR Polarimeter-Interferometer System MST Interferometer density fluctuation Faraday rotation magnetic field 11 chords, separation 8 cm,phase resolution 0.05 degree, time response up to 1  s Ding, Brower, et al PRL(2003),(2004) RSI(2004),(2008) See poster: P03-23(Bergerson)

Measurement of Equilibrium Magnetic Field and Current Denisty Time [ms] By Motion Stark Effect By Faraday rotation

Measurement of density and magnetic fluctuation Density fluctuations Radial Magnetic fluctuations m/n=1/6

Magnetic fluctuation-induced electron particle flux (Total Flux) Density fluctuation contributes to electron particle flux

Magnetic fluctuation-induced ion particle flux Den Hartog et. Al,PoP,1999 (Ion Flux) Velocity fluctuation contributes to ion flux

Magnetic Fluctuation Induced Flux Balances the Change of Density Integrating over time Magnetic fluctuation induced particle transport drives density change

Electron and ion flux arise from different mechanism Electron flux Ion flux Total flux

(m,n) are poloidal and toroidal mode number Ambipolarity of Particle Transport (difference between electron and ion particle flux) Ding, et al. PRL 2007

Particle diffusivity is (30X) larger than QL prediction Rechester&Rosenbluth(1978) (without ambipolarity ) ~~ (30 times) Predicted Particle Transport ~Predicted Heat Transport Experimentally, particle diffusion rate is approximately electron diffusion rate in a stochastic magnetic field. Harvey (1981) (with ambipolariy)

Summary (1)Rapid particle transport is observed in MST associated with the stochastic field; (2) Electron particle flux is comparable to ion flux ( ), accounting for global density change during a reconnection event; (3) Particle transport is much larger than the expected from quasi-linear theory.

Magnetic Fluctuation Measurement Method Plasma X 1 X 2 Ding, et al. PRL (2003)

Localization of Density Fluctuations Physically