Response of impurity particle confinement time to external actuators in QH-mode plasmas on DIII-D

Grierson, Brian A.; Burrell, Keith H.; Garofalo, Andrea M.; Solomon, Wayne M.; Diallo, Ahmed; O'Mullane, M.

doi:10.1088/0029-5515/54/11/114011

Title: Response of impurity particle confinement time to external actuators in QH-mode plasmas on DIII-D

Abstract

A series of quiescent H-mode discharges have been executed with the specific aim of determining the particle confinement time of impurities in the presence of the edge harmonic oscillation. These discharges utilize non-intrinsic, non-recycling fully-stripped fluorine as the diagnostic species monitored by charge-exchange recombination spectroscopy. It is found that the EHO is an efficient means of impurity expulsion from the core plasma, with impurity exhaust rates comparable to or exceeding those in companion ELMing discharges. Furthermore, as the external torque from neutral beam injection is lowered, the global energy confinement time increases while the impurity confinement time does not display an increase.

Authors:

Grierson, Brian A. ^[1]; Burrell, Keith H. ^[2]; Garofalo, Andrea M. ^[2]; Solomon, Wayne M. ^[1]; Diallo, Ahmed ^[1]; O'Mullane, M. ^[3]

Princeton Univ., Princeton, NJ (United States). Princeton Plasma Physics Lab.
General Atomics, San Diego, CA (United States)
Univ. of Strathclyde, Glasgow (United Kingdom)

Publication Date:: Tue Nov 04 00:00:00 EST 2014

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

Sponsoring Org.:: USDOE Office of Nuclear Energy (NE)

OSTI Identifier:: 1353062

Grant/Contract Number:: FC02-04ER54698

Resource Type:: Accepted Manuscript

Journal Name:: Nuclear Fusion

Additional Journal Information:: Journal Volume: 54; Journal Issue: 11; Journal ID: ISSN 0029-5515

Publisher:: IOP Science

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; plasma properties; plasma impurities; optical measurements

Citation Formats


                    Grierson, Brian A., Burrell, Keith H., Garofalo, Andrea M., Solomon, Wayne M., Diallo, Ahmed, and O'Mullane, M. Response of impurity particle confinement time to external actuators in QH-mode plasmas on DIII-D.  United States: N. p., 2014. 
Web.  doi:10.1088/0029-5515/54/11/114011.

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                    Grierson, Brian A., Burrell, Keith H., Garofalo, Andrea M., Solomon, Wayne M., Diallo, Ahmed, & O'Mullane, M. Response of impurity particle confinement time to external actuators in QH-mode plasmas on DIII-D.  United States.  https://doi.org/10.1088/0029-5515/54/11/114011

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                    Grierson, Brian A., Burrell, Keith H., Garofalo, Andrea M., Solomon, Wayne M., Diallo, Ahmed, and O'Mullane, M. Tue .  
"Response of impurity particle confinement time to external actuators in QH-mode plasmas on DIII-D".  United States.  https://doi.org/10.1088/0029-5515/54/11/114011.  https://www.osti.gov/servlets/purl/1353062.

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@article{osti_1353062,

  title        = {Response of impurity particle confinement time to external actuators in QH-mode plasmas on DIII-D},

  author       = {Grierson, Brian A. and Burrell, Keith H. and Garofalo, Andrea M. and Solomon, Wayne M. and Diallo, Ahmed and O'Mullane, M.},

  abstractNote = {A series of quiescent H-mode discharges have been executed with the specific aim of determining the particle confinement time of impurities in the presence of the edge harmonic oscillation. These discharges utilize non-intrinsic, non-recycling fully-stripped fluorine as the diagnostic species monitored by charge-exchange recombination spectroscopy. It is found that the EHO is an efficient means of impurity expulsion from the core plasma, with impurity exhaust rates comparable to or exceeding those in companion ELMing discharges. Furthermore, as the external torque from neutral beam injection is lowered, the global energy confinement time increases while the impurity confinement time does not display an increase.},

  doi          = {10.1088/0029-5515/54/11/114011},

  journal      = {Nuclear Fusion},

  number       = 11,

  volume       = 54,

  place        = {United States},

  year         = {Tue Nov 04 00:00:00 EST 2014},

  month        = {Tue Nov 04 00:00:00 EST 2014}

}

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Works referenced in this record:

Helium removal from tokamaks
journal, November 1991

Reiter, D.; Kever, H.; Wolf, G. H.
Plasma Physics and Controlled Fusion, Vol. 33, Issue 13
DOI: 10.1088/0741-3335/33/13/008

Low-Z impurity transport in DIII-D – observations and implications
journal, March 2001

Wade, M. R.; Houlberg, W. A.; Baylor, L. R.
Journal of Nuclear Materials, Vol. 290-293
DOI: 10.1016/S0022-3115(00)00499-2

Quiescent double barrier high-confinement mode plasmas in the DIII-D tokamak
journal, May 2001

Burrell, K. H.; Austin, M. E.; Brennan, D. P.
Physics of Plasmas, Vol. 8, Issue 5
DOI: 10.1063/1.1355981

The role of radial particle flow on power balance in DIII-D
journal, December 1998

Porter, G. D.
Physics of Plasmas, Vol. 5, Issue 12
DOI: 10.1063/1.873169

Advances towards QH-mode viability for ELM-stable operation in ITER
journal, July 2011

Garofalo, A. M.; Solomon, W. M.; Park, J. -K.
Nuclear Fusion, Vol. 51, Issue 8
DOI: 10.1088/0029-5515/51/8/083018

Influence of toroidal rotation on transport and stability in hybrid scenario plasmas in DIII-D
journal, May 2008

Politzer, P. A.; Petty, C. C.; Jayakumar, R. J.
Nuclear Fusion, Vol. 48, Issue 7
DOI: 10.1088/0029-5515/48/7/075001

Access to high beta advanced inductive plasmas at low injected torque
journal, September 2013

Solomon, W. M.; Politzer, P. A.; Buttery, R. J.
Nuclear Fusion, Vol. 53, Issue 9
DOI: 10.1088/0029-5515/53/9/093033

Reactor-relevant quiescent H-mode operation using torque from non-axisymmetric, non-resonant magnetic fields
journal, May 2012

Burrell, K. H.; Garofalo, A. M.; Solomon, W. M.
Physics of Plasmas, Vol. 19, Issue 5
DOI: 10.1063/1.3695119

Quiescent H-mode operation using torque from non-axisymmetric, non-resonant magnetic fields
journal, June 2013

Burrell, K. H.; Garofalo, A. M.; Solomon, W. M.
Nuclear Fusion, Vol. 53, Issue 7
DOI: 10.1088/0029-5515/53/7/073038

Works referencing / citing this record:

Discovery of stationary operation of quiescent H-mode plasmas with net-zero neutral beam injection torque and high energy confinement on DIII-D
journal, March 2016

Burrell, K. H.; Barada, K.; Chen, X.
Physics of Plasmas, Vol. 23, Issue 5
DOI: 10.1063/1.4943521

Validation of the kinetic-turbulent-neoclassical theory for edge intrinsic rotation in DIII-D
journal, May 2018

Ashourvan, Arash; Grierson, B. A.; Battaglia, D. J.
Physics of Plasmas, Vol. 25, Issue 5
DOI: 10.1063/1.5018326

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Similar Records

Title: Response of impurity particle confinement time to external actuators in QH-mode plasmas on DIII-D

Abstract

Citation Formats

Helium removal from tokamaks journal, November 1991

Low-Z impurity transport in DIII-D – observations and implications journal, March 2001

Quiescent double barrier high-confinement mode plasmas in the DIII-D tokamak journal, May 2001

The role of radial particle flow on power balance in DIII-D journal, December 1998

Advances towards QH-mode viability for ELM-stable operation in ITER journal, July 2011

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Access to high beta advanced inductive plasmas at low injected torque journal, September 2013

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Quiescent H-mode operation using torque from non-axisymmetric, non-resonant magnetic fields journal, June 2013

Discovery of stationary operation of quiescent H-mode plasmas with net-zero neutral beam injection torque and high energy confinement on DIII-D journal, March 2016

Validation of the kinetic-turbulent-neoclassical theory for edge intrinsic rotation in DIII-D journal, May 2018

Helium removal from tokamaks
journal, November 1991

Low-Z impurity transport in DIII-D – observations and implications
journal, March 2001

Quiescent double barrier high-confinement mode plasmas in the DIII-D tokamak
journal, May 2001

The role of radial particle flow on power balance in DIII-D
journal, December 1998

Advances towards QH-mode viability for ELM-stable operation in ITER
journal, July 2011

Influence of toroidal rotation on transport and stability in hybrid scenario plasmas in DIII-D
journal, May 2008

Access to high beta advanced inductive plasmas at low injected torque
journal, September 2013

Reactor-relevant quiescent H-mode operation using torque from non-axisymmetric, non-resonant magnetic fields
journal, May 2012

Quiescent H-mode operation using torque from non-axisymmetric, non-resonant magnetic fields
journal, June 2013

Discovery of stationary operation of quiescent H-mode plasmas with net-zero neutral beam injection torque and high energy confinement on DIII-D
journal, March 2016

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journal, May 2018