RADIAL TRANSPORT EFFECTS ON ECCD IN THE TCV AND DIII-D TOKAMAKS AND ON OHMIC DISCHARGES IN THE MST RFP

HARVEY, R W; SAUTER, O; PRATER, R; NIKKOLA, P; O'CONNELL, R; FOREST, C B

Title: RADIAL TRANSPORT EFFECTS ON ECCD IN THE TCV AND DIII-D TOKAMAKS AND ON OHMIC DISCHARGES IN THE MST RFP

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Abstract

The comprehensive CQL3D Fokker-Planck/Quasilinear simulation code has been benchmarked against experiment over a wide range of electron cyclotron conditions in the DIII-D tokamak (C.C. Petty et al., 14th Topical Conf. on RF Power in Plasmas, 2002). The same code, in disagreement with experiment, gives 560 kA of ECCD for a well documented, completely ECCD-driven, 100 kA TCV shot [O. Sauter et al, PRL, 2000]. Recent work (R.W. Harvey et al, Phys. Rev. Lett., 2002) has resolved the differences as due to radial transport at a level closely consistent with ITER scaling. Transport does not substantially affect DIII-D ECCD, but at similar ECH power has an overwhelming effect on the much smaller TCV. The transport is consistent with electrostatic-type diffusion (D{sub {rho}{rho}} constant in velocity-space) and not with a magnetic-type diffusion (D{sub {rho}{rho}} {proportional_to} |v{parallel}|). Fokker-Planck simulation of Ohmic reversed field pinch (RFP) discharges in the MST device reveals transport velocity dependence stronger than |v{parallel}| will give agreement with current and soft X-ray spectra in standard discharges, but in the higher confinement, current profile controlled PPCD discharges, transport is again electrostatic-like. This is consistent with the object of PPCD, which is to replace magnetic turbulence driven current with auxiliary CD tomore »« less

Authors:: HARVEY, R W; SAUTER, O; PRATER, R; NIKKOLA, P; O'CONNELL, R; FOREST, C B

Publication Date:: Mon Jul 01 00:00:00 EDT 2002

Research Org.:: General Atomics, San Diego, CA (United States)

Sponsoring Org.:: (US)

OSTI Identifier:: 804667

DOE Contract Number:: AC03-99ER54463

Resource Type:: Conference

Resource Relation:: Conference: 12th Joint Workshop on Electron Cyclotron Emission and Electron Cyclotron Resonance Heating, Aix-En-Provence (FR), 05/13/2002--05/16/2002; Other Information: THIS IS A PREPRINT OF A PAPER PRESENTED AT THE 12TH JOINT WORKSHOP ON ELECTRON CYCLOTRON EMISSION AND ELECTRON CYCLOTRON RESONANCE HEATING, MAY 13-16, 2002, IN AIX-EN-PROVENCE, FRANCE AND TO BE PUBLISHED IN THE ''PROCEEDINGS''; PBD: 1 Jul 2002

Country of Publication:: United States

Language:: English

Subject:: 43 PARTICLE ACCELERATORS; CONFINEMENT; CYCLOTRONS; DIFFUSION; DOUBLET-3 DEVICE; ECR HEATING; ELECTRONS; MST DEVICE; SIMULATION; TRANSPORT; TURBULENCE; VELOCITY; X-RAY SPECTRA

Citation Formats


                    HARVEY, R W, SAUTER, O, PRATER, R, NIKKOLA, P, O'CONNELL, R, and FOREST, C B. RADIAL TRANSPORT EFFECTS ON ECCD IN THE TCV AND DIII-D TOKAMAKS AND ON OHMIC DISCHARGES IN THE MST RFP.  United States: N. p., 2002. 
        Web.

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                    HARVEY, R W, SAUTER, O, PRATER, R, NIKKOLA, P, O'CONNELL, R, & FOREST, C B. RADIAL TRANSPORT EFFECTS ON ECCD IN THE TCV AND DIII-D TOKAMAKS AND ON OHMIC DISCHARGES IN THE MST RFP.  United States.

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                    HARVEY, R W, SAUTER, O, PRATER, R, NIKKOLA, P, O'CONNELL, R, and FOREST, C B. 2002.  
        "RADIAL TRANSPORT EFFECTS ON ECCD IN THE TCV AND DIII-D TOKAMAKS AND ON OHMIC DISCHARGES IN THE MST RFP".  United States.  https://www.osti.gov/servlets/purl/804667.

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@article{osti_804667,

  title        = {RADIAL TRANSPORT EFFECTS ON ECCD IN THE TCV AND DIII-D TOKAMAKS AND ON OHMIC DISCHARGES IN THE MST RFP},

  author       = {HARVEY, R W and SAUTER, O and PRATER, R and NIKKOLA, P and O'CONNELL, R and FOREST, C B},

  abstractNote = {The comprehensive CQL3D Fokker-Planck/Quasilinear simulation code has been benchmarked against experiment over a wide range of electron cyclotron conditions in the DIII-D tokamak (C.C. Petty et al., 14th Topical Conf. on RF Power in Plasmas, 2002). The same code, in disagreement with experiment, gives 560 kA of ECCD for a well documented, completely ECCD-driven, 100 kA TCV shot [O. Sauter et al, PRL, 2000]. Recent work (R.W. Harvey et al, Phys. Rev. Lett., 2002) has resolved the differences as due to radial transport at a level closely consistent with ITER scaling. Transport does not substantially affect DIII-D ECCD, but at similar ECH power has an overwhelming effect on the much smaller TCV. The transport is consistent with electrostatic-type diffusion (D{sub {rho}{rho}} constant in velocity-space) and not with a magnetic-type diffusion (D{sub {rho}{rho}} {proportional_to} |v{parallel}|). Fokker-Planck simulation of Ohmic reversed field pinch (RFP) discharges in the MST device reveals transport velocity dependence stronger than |v{parallel}| will give agreement with current and soft X-ray spectra in standard discharges, but in the higher confinement, current profile controlled PPCD discharges, transport is again electrostatic-like. This is consistent with the object of PPCD, which is to replace magnetic turbulence driven current with auxiliary CD to improve transport. The tokamak and high-confinement RFP results mutually reinforce the constant-in-velocity-space ''electrostatic-type turbulence'' conclusion. The steady-state energy and toroidal current are governed by the same radial transport equation.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/804667},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Mon Jul 01 00:00:00 EDT 2002},

  month        = {Mon Jul 01 00:00:00 EDT 2002}

}

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