The contribution of radio-frequency rectification to field-aligned losses of high-harmonic fast wave power to the divertor in the National Spherical Torus eXperiment
Abstract
The National Spherical Torus eXperiment (NSTX) can exhibit a major loss of high-harmonic fast wave (HHFW) power along scrape-off layer (SOL) field lines passing in front of the antenna, resulting in bright and hot spirals on both the upper and lower divertor regions. One possible mechanism for this loss is RF sheaths forming at the divertors. We demonstrate that swept-voltage Langmuir probe characteristics for probes under the spiral are shifted relative to those not under the spiral in a manner consistent with RF rectification. We estimate both the magnitude of the RF voltage across the sheath and the sheath heat flux transmission coefficient in the presence of the RF field. Though the precise comparison between computed heat flux and infrared (IR) thermography cannot yet be made, the computed heat deposition compares favorably with the projections from IR camera measurements. The RF sheath losses are significant and contribute substantially to the total SOL losses of HHFW power to the divertor for the cases studied. Our work will guide future experimentation on NSTX-U, where a wide-angle IR camera and a dedicated set of coaxial Langmuir probes for measuring the RF sheath voltage directly will quantify the contribution of RF sheath rectification tomore »
- Authors:
-
[1];
[1]
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Columbia Univ., New York, NY (United States)
- Publication Date:
- Research Org.:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC)
- OSTI Identifier:
- 1279419
- Alternate Identifier(s):
- OSTI ID: 1228291
- Grant/Contract Number:
- AC05-00OR22725; AC02-09CH11466
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Physics of Plasmas
- Additional Journal Information:
- Journal Volume: 22; Journal Issue: 4; Journal ID: ISSN 1070-664X
- Publisher:
- American Institute of Physics (AIP)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY
Citation Formats
Perkins, R. J., Hosea, J. C., Jaworski, M. A., Ahn, J. -W., Diallo, A., Bell, R. E., Bertelli, N., Gerhardt, S., Gray, T. K., Kramer, G. J., LeBlanc, B. P., McLean, A., Phillips, C. K., Podestà , M., Roquemore, L., Sabbagh, S., Taylor, G., and Wilson, J. R. The contribution of radio-frequency rectification to field-aligned losses of high-harmonic fast wave power to the divertor in the National Spherical Torus eXperiment. United States: N. p., 2015.
Web. doi:10.1063/1.4916034.
Perkins, R. J., Hosea, J. C., Jaworski, M. A., Ahn, J. -W., Diallo, A., Bell, R. E., Bertelli, N., Gerhardt, S., Gray, T. K., Kramer, G. J., LeBlanc, B. P., McLean, A., Phillips, C. K., Podestà , M., Roquemore, L., Sabbagh, S., Taylor, G., & Wilson, J. R. The contribution of radio-frequency rectification to field-aligned losses of high-harmonic fast wave power to the divertor in the National Spherical Torus eXperiment. United States. https://doi.org/10.1063/1.4916034
Perkins, R. J., Hosea, J. C., Jaworski, M. A., Ahn, J. -W., Diallo, A., Bell, R. E., Bertelli, N., Gerhardt, S., Gray, T. K., Kramer, G. J., LeBlanc, B. P., McLean, A., Phillips, C. K., Podestà , M., Roquemore, L., Sabbagh, S., Taylor, G., and Wilson, J. R. Mon .
"The contribution of radio-frequency rectification to field-aligned losses of high-harmonic fast wave power to the divertor in the National Spherical Torus eXperiment". United States. https://doi.org/10.1063/1.4916034. https://www.osti.gov/servlets/purl/1279419.
@article{osti_1279419,
title = {The contribution of radio-frequency rectification to field-aligned losses of high-harmonic fast wave power to the divertor in the National Spherical Torus eXperiment},
author = {Perkins, R. J. and Hosea, J. C. and Jaworski, M. A. and Ahn, J. -W. and Diallo, A. and Bell, R. E. and Bertelli, N. and Gerhardt, S. and Gray, T. K. and Kramer, G. J. and LeBlanc, B. P. and McLean, A. and Phillips, C. K. and Podestà , M. and Roquemore, L. and Sabbagh, S. and Taylor, G. and Wilson, J. R.},
abstractNote = {The National Spherical Torus eXperiment (NSTX) can exhibit a major loss of high-harmonic fast wave (HHFW) power along scrape-off layer (SOL) field lines passing in front of the antenna, resulting in bright and hot spirals on both the upper and lower divertor regions. One possible mechanism for this loss is RF sheaths forming at the divertors. We demonstrate that swept-voltage Langmuir probe characteristics for probes under the spiral are shifted relative to those not under the spiral in a manner consistent with RF rectification. We estimate both the magnitude of the RF voltage across the sheath and the sheath heat flux transmission coefficient in the presence of the RF field. Though the precise comparison between computed heat flux and infrared (IR) thermography cannot yet be made, the computed heat deposition compares favorably with the projections from IR camera measurements. The RF sheath losses are significant and contribute substantially to the total SOL losses of HHFW power to the divertor for the cases studied. Our work will guide future experimentation on NSTX-U, where a wide-angle IR camera and a dedicated set of coaxial Langmuir probes for measuring the RF sheath voltage directly will quantify the contribution of RF sheath rectification to the heat deposition from the SOL to the divertor.},
doi = {10.1063/1.4916034},
journal = {Physics of Plasmas},
number = 4,
volume = 22,
place = {United States},
year = {Mon Apr 13 00:00:00 EDT 2015},
month = {Mon Apr 13 00:00:00 EDT 2015}
}
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Works referenced in this record:
A description of the full-particle-orbit-following SPIRAL code for simulating fast-ion experiments in tokamaks
journal, January 2013
- Kramer, G. J.; Budny, R. V.; Bortolon, A.
- Plasma Physics and Controlled Fusion, Vol. 55, Issue 2
Far field sheaths from waves in the ion cyclotron range of frequencies
journal, September 1994
- Myra, J. R.; D’Ippolito, D. A.; Bures, M.
- Physics of Plasmas, Vol. 1, Issue 9
SPIRAL field mapping on NSTX for comparison to divertor RF heat deposition
conference, January 2014
- Hosea, J. C.; Perkins, R.; Jaworski, M. A.
- RADIOFREQUENCY POWER IN PLASMAS: Proceedings of the 20th Topical Conference, AIP Conference Proceedings
Fast wave current drive in H mode plasmas on the DIII-D tokamak
journal, October 1999
- Petty, C. C.; Baity, F. W.; deGrassie, J. S.
- Nuclear Fusion, Vol. 39, Issue 10
Effects of toroidal rotation shear on toroidicity-induced Alfvén eigenmodes in the National Spherical Torus Experiment
journal, December 2010
- Podestà , M.; Bell, R. E.; Fredrickson, E. D.
- Physics of Plasmas, Vol. 17, Issue 12
Characterisation of local ICRF heat loads on the JET ILW
journal, July 2013
- Jacquet, P.; Marcotte, F.; Colas, L.
- Journal of Nuclear Materials, Vol. 438
Suppression of energetic particle driven instabilities with HHFW heating
journal, December 2014
- Fredrickson, E. D.; Taylor, G.; Bertelli, N.
- Nuclear Fusion, Vol. 55, Issue 1
Modeling far-field radio-frequency sheaths in Alcator C-Mod
journal, May 2013
- D'Ippolito, D. A.; Myra, J. R.; Ochoukov, R.
- Plasma Physics and Controlled Fusion, Vol. 55, Issue 8
Plasma Sheath Formation by Radio-Frequency Fields
journal, January 1963
- Butler, H. S.; Kino, G. S.
- Physics of Fluids, Vol. 6, Issue 9
Characterization and performance of a field aligned ion cyclotron range of frequency antenna in Alcator C-Mod
journal, May 2013
- Wukitch, S. J.; Garrett, M. L.; Ochoukov, R.
- Physics of Plasmas, Vol. 20, Issue 5
Surface thermocouples for measurement of pulsed heat flux in the divertor of the Alcator C-Mod tokamak
journal, March 2012
- Brunner, D.; LaBombard, B.
- Review of Scientific Instruments, Vol. 83, Issue 3
High harmonic fast waves in high beta plasmas
journal, November 1995
- Ono, Masayuki
- Physics of Plasmas, Vol. 2, Issue 11
Fast-wave power flow along SOL field lines in NSTX and the associated power deposition profile across the SOL in front of the antenna
journal, July 2013
- Perkins, R. J.; Ahn, J. -W.; Bell, R. E.
- Nuclear Fusion, Vol. 53, Issue 8
High-Harmonic Fast-Wave Power Flow along Magnetic Field Lines in the Scrape-Off Layer of NSTX
journal, July 2012
- Perkins, R. J.; Hosea, J. C.; Kramer, G. J.
- Physical Review Letters, Vol. 109, Issue 4
Edge rotation and temperature diagnostic on the National Spherical Torus Experiment
journal, March 2004
- Biewer, T. M.; Bell, R. E.; Feder, R.
- Review of Scientific Instruments, Vol. 75, Issue 3
Techniques for the measurement of disruption halo currents in the National Spherical Torus Experiment
journal, October 2011
- Gerhardt, S. P.; Fredrickson, E.; Guttadora, L.
- Review of Scientific Instruments, Vol. 82, Issue 10
High density Langmuir probe array for NSTX scrape-off layer measurements under lithiated divertor conditions
journal, October 2010
- Kallman, J.; Jaworski, M. A.; Kaita, R.
- Review of Scientific Instruments, Vol. 81, Issue 10
Theory of a Probe in a Strong Magnetic Field
journal, January 1970
- Sanmartin, Juan R.
- Physics of Fluids, Vol. 13, Issue 1
Assessment of compatibility of ICRF antenna operation with full W wall in ASDEX Upgrade
journal, February 2010
- Bobkov, Vl. V.; Braun, F.; Dux, R.
- Nuclear Fusion, Vol. 50, Issue 3
High harmonic fast wave heating efficiency enhancement and current drive at longer wavelength on the National Spherical Torus Experiment
journal, May 2008
- Hosea, J.; Bell, R. E.; LeBlanc, B. P.
- Physics of Plasmas, Vol. 15, Issue 5
Profiles of fast ions that are accelerated by high harmonic fast waves in the National Spherical Torus Experiment
journal, January 2010
- Liu, D.; Heidbrink, W. W.; Podestà , M.
- Plasma Physics and Controlled Fusion, Vol. 52, Issue 2
Biasing, acquisition, and interpretation of a dense Langmuir probe array in NSTX
journal, October 2010
- Jaworski, M. A.; Kallman, J.; Kaita, R.
- Review of Scientific Instruments, Vol. 81, Issue 10
Spectral effects on fast wave core heating and current drive
journal, June 2009
- Phillips, C. K.; Bell, R. E.; Berry, L. A.
- Nuclear Fusion, Vol. 49, Issue 7
Estimated RF sheath power fluxes on ITER plasma facing components
journal, June 2009
- Colas, L.; Milanesio, D.; Faudot, E.
- Journal of Nuclear Materials, Vol. 390-391
Infrared camera diagnostic for heat flux measurements on the National Spherical Torus Experiment
journal, December 2003
- Mastrovito, D.; Maingi, R.; Kugel, H. W.
- Review of Scientific Instruments, Vol. 74, Issue 12
Full wave simulations of fast wave heating losses in the scrape-off layer of NSTX and NSTX-U
journal, May 2014
- Bertelli, N.; Jaeger, E. F.; Hosea, J. C.
- Nuclear Fusion, Vol. 54, Issue 8
Exploration of spherical torus physics in the NSTX device
journal, March 2000
- Ono, M.; Kaye, S. M.; Peng, Y. -K. M.
- Nuclear Fusion, Vol. 40, Issue 3Y
Effect of a R.F, signal on the characteristic of a langmuir probe
journal, July 1963
- Boschi, A.; Magistrelli, F.
- Il Nuovo Cimento, Vol. 29, Issue 2
Divertor sheath power studies in DIII-D using fixed Langmuir probes and three-dimensional modeling of tile heat flows
journal, April 2014
- Donovan, D.; Nygren, R.; Buchenauer, D.
- Physica Scripta, Vol. T159
Advanced ST plasma scenario simulations for NSTX
journal, July 2005
- Kessel, C. E.; Synakowski, E. J.; Bell, M. E.
- Nuclear Fusion, Vol. 45, Issue 8
RF sheath-enhanced beryllium sources at JET’s ICRH antennas
journal, July 2013
- Klepper, C. C.; Jacquet, P.; Bobkov, V.
- Journal of Nuclear Materials, Vol. 438
Towards identifying the mechanisms underlying field-aligned edge-loss of HHFW power on NSTX
conference, January 2014
- Perkins, R. J.; Ahn, J-W.; Bell, R. E.
- RADIOFREQUENCY POWER IN PLASMAS: Proceedings of the 20th Topical Conference, AIP Conference Proceedings
Advances in high-harmonic fast wave physics in the National Spherical Torus Experiment
journal, May 2010
- Taylor, G.; Bell, R. E.; Hosea, J. C.
- Physics of Plasmas, Vol. 17, Issue 5
ITER ion cyclotron system: Overview and plans
journal, October 2007
- Swain, D. W.; Goulding, R. H.
- Fusion Engineering and Design, Vol. 82, Issue 5-14
Investigation of the fluxes to a surface at grazing angles of incidence in the tokamak boundary
journal, December 1990
- Matthews, G. F.; Fielding, S. J.; McCracken, G. M.
- Plasma Physics and Controlled Fusion, Vol. 32, Issue 14
Edge ion heating by launched high harmonic fast waves in the National Spherical Torus Experiment
journal, May 2005
- Biewer, T. M.; Bell, R. E.; Diem, S. J.
- Physics of Plasmas, Vol. 12, Issue 5
Recent Fast Wave Coupling and Heating Studies on NSTX, with Possible Implications for ITER
conference, January 2009
- Hosea, J. C.; Bell, R. E.; Feibush, E.
- RADIO FREQUENCY POWER IN PLASMAS: Proceedings of the 18th Topical Conference, AIP Conference Proceedings
Notes on the Effect of Noise on Langmuir Probe Characteristics
journal, March 1962
- Garscadden, A.; Emeleus, K. G.
- Proceedings of the Physical Society, Vol. 79, Issue 3
Works referencing / citing this record:
Resonance in fast-wave amplitude in the periphery of cylindrical plasmas and application to edge losses of wave heating power in tokamaks
journal, July 2016
- Perkins, R. J.; Hosea, J. C.; Bertelli, N.
- Physics of Plasmas, Vol. 23, Issue 7
Resolving interactions between ion-cyclotron range of frequencies heating and the scrape-off layer plasma in EAST using divertor probes
journal, March 2019
- Perkins, R. J.; Hosea, J. C.; Taylor, G.
- Plasma Physics and Controlled Fusion, Vol. 61, Issue 4