Turbulence induced radial transport of toroidal momentum in boundary plasma of EAST tokamak
Abstract
Turbulence induced toroidal momentum transport in boundary plasma is investigated in Hmode discharge using LangmuirMach probes on EAST. The Reynolds stress is found to drive an inward toroidal momentum transport, while the outflow of particles convects the toroidal momentum outwards in the edge plasma. The Reynolds stress driven momentum transport dominates over the passive momentum transport carried by particle flux, which potentially provides a momentum source for the edge plasma. The outflow of particles delivers a momentum flux into the scrapeoff layer (SOL) region, contributing as a momentum source for the SOL flows. At the LH transitions, the outward momentum transport suddenly decreases due to the suppression of edge turbulence and associated particle transport. The SOL flows start to decelerate as plasma entering into Hmode. The contributions from turbulent Reynolds stress and particle transport for the toroidal momentum transport are identified. These results shed lights on the understanding of edge plasma accelerating at LH transitions.
 Authors:
 MOE Key Laboratory of Materials Modification by Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)
 (China)
 Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)
 Publication Date:
 OSTI Identifier:
 22598986
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; HMODE PLASMA CONFINEMENT; HT7U TOKAMAK; LANGMUIR PROBE; MACH NUMBER; PARTICLES; PLASMA; PLASMA SCRAPEOFF LAYER; REYNOLDS NUMBER; STRESSES; TRANSPORT THEORY; TURBULENCE
Citation Formats
Zhao, N., Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, Yan, N., Email: yanning@ipp.ac.cn, Xu, G. S., Wang, H. Q., Wang, L., Ding, S. Y., Chen, R., Chen, L., Zhang, W., Hu, G. H., Shao, L. M., and Wang, Z. X., Email: zxwang@dlut.edu.cn. Turbulence induced radial transport of toroidal momentum in boundary plasma of EAST tokamak. United States: N. p., 2016.
Web. doi:10.1063/1.4953601.
Zhao, N., Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, Yan, N., Email: yanning@ipp.ac.cn, Xu, G. S., Wang, H. Q., Wang, L., Ding, S. Y., Chen, R., Chen, L., Zhang, W., Hu, G. H., Shao, L. M., & Wang, Z. X., Email: zxwang@dlut.edu.cn. Turbulence induced radial transport of toroidal momentum in boundary plasma of EAST tokamak. United States. doi:10.1063/1.4953601.
Zhao, N., Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, Yan, N., Email: yanning@ipp.ac.cn, Xu, G. S., Wang, H. Q., Wang, L., Ding, S. Y., Chen, R., Chen, L., Zhang, W., Hu, G. H., Shao, L. M., and Wang, Z. X., Email: zxwang@dlut.edu.cn. 2016.
"Turbulence induced radial transport of toroidal momentum in boundary plasma of EAST tokamak". United States.
doi:10.1063/1.4953601.
@article{osti_22598986,
title = {Turbulence induced radial transport of toroidal momentum in boundary plasma of EAST tokamak},
author = {Zhao, N. and Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 and Yan, N., Email: yanning@ipp.ac.cn and Xu, G. S. and Wang, H. Q. and Wang, L. and Ding, S. Y. and Chen, R. and Chen, L. and Zhang, W. and Hu, G. H. and Shao, L. M. and Wang, Z. X., Email: zxwang@dlut.edu.cn},
abstractNote = {Turbulence induced toroidal momentum transport in boundary plasma is investigated in Hmode discharge using LangmuirMach probes on EAST. The Reynolds stress is found to drive an inward toroidal momentum transport, while the outflow of particles convects the toroidal momentum outwards in the edge plasma. The Reynolds stress driven momentum transport dominates over the passive momentum transport carried by particle flux, which potentially provides a momentum source for the edge plasma. The outflow of particles delivers a momentum flux into the scrapeoff layer (SOL) region, contributing as a momentum source for the SOL flows. At the LH transitions, the outward momentum transport suddenly decreases due to the suppression of edge turbulence and associated particle transport. The SOL flows start to decelerate as plasma entering into Hmode. The contributions from turbulent Reynolds stress and particle transport for the toroidal momentum transport are identified. These results shed lights on the understanding of edge plasma accelerating at LH transitions.},
doi = {10.1063/1.4953601},
journal = {Physics of Plasmas},
number = 6,
volume = 23,
place = {United States},
year = 2016,
month = 6
}

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