Experimental Investigation of the Role of Fluid Turbulent Stresses and Edge Plasma Flows for Intrinsic Rotation Generation in DIII-D H-Mode Plasmas

doi:https://doi.org/10.1103/PHYSREVLETT.106.115001

Title: Experimental Investigation of the Role of Fluid Turbulent Stresses and Edge Plasma Flows for Intrinsic Rotation Generation in DIII-D H-Mode Plasmas

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Abstract

The first measurements of turbulent stresses and flows inside the separatrix of a tokamak H-mode plasma are reported, using a reciprocating multitip Langmuir probe at the DIII-D tokamak. A strong co-current rotation layer at the separatrix is found to precede intrinsic rotation development in the core. The measured fluid turbulent stresses transport toroidal momentum outward against the velocity gradient and thus try to sustain the edge layer. However, large kinetic stresses must exist to explain the net inward momentum transport leading to co-current core plasma rotation. The importance of such kinetic stresses is corroborated by the success of a simple orbit loss model, representing a purely kinetic mechanism, in the prediction of features of the edge corotation layer.

Authors:

Mueller, S H ^[1]; Boedo, J A; Moyer, R A; Rudakov, D L ^[2]; Burrell, K H; Grassie, J S. de ^[3]; Solomon, W M ^[4]

Center for Energy Research, University of California of San Diego, 9500 Gilman Drive, M/C 0417, La Jolla, California 92093 (United States); Center for Momentum Transport and Flow Organization (United States)
Center for Energy Research, University of California of San Diego, 9500 Gilman Drive, M/C 0417, La Jolla, California 92093 (United States)
General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)
Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543-0451 (United States)

Publication Date:: 2011-03-18

OSTI Identifier:: 21562103

Resource Type:: Journal Article

Journal Name:: Physical Review Letters

Additional Journal Information:: Journal Volume: 106; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevLett.106.115001; (c) 2011 American Institute of Physics; Journal ID: ISSN 0031-9007

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DOUBLET-3 DEVICE; FLUIDS; H-MODE PLASMA CONFINEMENT; LANGMUIR PROBE; PLASMA; STRESSES; VELOCITY; CLOSED PLASMA DEVICES; CONFINEMENT; ELECTRIC PROBES; MAGNETIC CONFINEMENT; PLASMA CONFINEMENT; PROBES; THERMONUCLEAR DEVICES; TOKAMAK DEVICES

Citation Formats


                    Mueller, S H, Boedo, J A, Moyer, R A, Rudakov, D L, Burrell, K H, Grassie, J S. de, and Solomon, W M. Experimental Investigation of the Role of Fluid Turbulent Stresses and Edge Plasma Flows for Intrinsic Rotation Generation in DIII-D H-Mode Plasmas.  United States: N. p., 2011. 
        Web.  doi:10.1103/PHYSREVLETT.106.115001.

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                    Mueller, S H, Boedo, J A, Moyer, R A, Rudakov, D L, Burrell, K H, Grassie, J S. de, & Solomon, W M. Experimental Investigation of the Role of Fluid Turbulent Stresses and Edge Plasma Flows for Intrinsic Rotation Generation in DIII-D H-Mode Plasmas.  United States.  https://doi.org/10.1103/PHYSREVLETT.106.115001

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                    Mueller, S H, Boedo, J A, Moyer, R A, Rudakov, D L, Burrell, K H, Grassie, J S. de, and Solomon, W M. Fri .  
        "Experimental Investigation of the Role of Fluid Turbulent Stresses and Edge Plasma Flows for Intrinsic Rotation Generation in DIII-D H-Mode Plasmas".  United States.  https://doi.org/10.1103/PHYSREVLETT.106.115001.

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@article{osti_21562103,

  title        = {Experimental Investigation of the Role of Fluid Turbulent Stresses and Edge Plasma Flows for Intrinsic Rotation Generation in DIII-D H-Mode Plasmas},

  author       = {Mueller, S H and Boedo, J A and Moyer, R A and Rudakov, D L and Burrell, K H and Grassie, J S. de and Solomon, W M},

  abstractNote = {The first measurements of turbulent stresses and flows inside the separatrix of a tokamak H-mode plasma are reported, using a reciprocating multitip Langmuir probe at the DIII-D tokamak. A strong co-current rotation layer at the separatrix is found to precede intrinsic rotation development in the core. The measured fluid turbulent stresses transport toroidal momentum outward against the velocity gradient and thus try to sustain the edge layer. However, large kinetic stresses must exist to explain the net inward momentum transport leading to co-current core plasma rotation. The importance of such kinetic stresses is corroborated by the success of a simple orbit loss model, representing a purely kinetic mechanism, in the prediction of features of the edge corotation layer.},

  doi          = {10.1103/PHYSREVLETT.106.115001},

  url          = {https://www.osti.gov/biblio/21562103},
  journal      = {Physical Review Letters},

  issn         = {0031-9007},

  number       = 11,

  volume       = 106,

  place        = {United States},

  year         = {2011},

  month        = {3}

}

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