Modeling ExB drift transport in conceptual slot divertor configurations
Abstract
At DIII-D, a slot divertor concept, called small-angle-slot (SAS), is under development, aiming to enable detachment at relatively low plasma edge density. We report on simulations using the SOLPS-ITER two-dimensional edge code to examine the performance of conceptual “SAS 2” slot configurations. The focus of the analysis is on E × B drift effects on upstream density at detachment (UDD), with detachment marked by electron temperature Te ≤ 3 eV at the outer strike point (OSP). With toroidal field such that radial E × B drift carries particles from the OSP towards the private flux region (PFR), placing the OSP near the inner slot wall gives ≈20% lower UDD than having the OSP near the outer wall. The inner wall effectively traps the radial E × B drift flux, resulting in low Te and associated radial electric field in the PFR, and thus small losses from the slot to the inner target via poloidal E × B drift flux. With toroidal field reversed such that radial E × B drift is reversed, OSP placement near the inner wall gives ≈10% lower UDD than OSP placement near the outer wall. Although radial E × B flux is from the OSP towardsmore »
- Authors:
-
- Univ. of Washington, Seattle, WA (United States)
- General Atomics, San Diego, CA (United States)
- Publication Date:
- Research Org.:
- Univ. of Washington, Seattle, WA (United States)
- Sponsoring Org.:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE), Office of Technology Utilization (EE-34); USDOE Office of Science (SC), Fusion Energy Sciences (FES)
- OSTI Identifier:
- 1601921
- Alternate Identifier(s):
- OSTI ID: 1599915
- Grant/Contract Number:
- SC0019473; FC02-04ER54698
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Contributions to Plasma Physics
- Additional Journal Information:
- Journal Volume: 60; Journal Issue: 5-6; Conference: Plasma Edge Theory Workshop, San Diego, CA (United States), Aug. 19-21, 2019; Journal ID: ISSN 0863-1042
- Publisher:
- Wiley
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 99 GENERAL AND MISCELLANEOUS; tokamak; divertor; plasma physics; modeling; detachment; DIII-D; ExB drifts; SAS 2 slot divertor; SOLPS-ITER
Citation Formats
Meier, E. T., Covele, B. M., Guo, H. Y., Leonard, A. W., and Thomas, D. M. Modeling ExB drift transport in conceptual slot divertor configurations. United States: N. p., 2020.
Web. doi:10.1002/ctpp.201900151.
Meier, E. T., Covele, B. M., Guo, H. Y., Leonard, A. W., & Thomas, D. M. Modeling ExB drift transport in conceptual slot divertor configurations. United States. https://doi.org/10.1002/ctpp.201900151
Meier, E. T., Covele, B. M., Guo, H. Y., Leonard, A. W., and Thomas, D. M. Sat .
"Modeling ExB drift transport in conceptual slot divertor configurations". United States. https://doi.org/10.1002/ctpp.201900151. https://www.osti.gov/servlets/purl/1601921.
@article{osti_1601921,
title = {Modeling ExB drift transport in conceptual slot divertor configurations},
author = {Meier, E. T. and Covele, B. M. and Guo, H. Y. and Leonard, A. W. and Thomas, D. M.},
abstractNote = {At DIII-D, a slot divertor concept, called small-angle-slot (SAS), is under development, aiming to enable detachment at relatively low plasma edge density. We report on simulations using the SOLPS-ITER two-dimensional edge code to examine the performance of conceptual “SAS 2” slot configurations. The focus of the analysis is on E × B drift effects on upstream density at detachment (UDD), with detachment marked by electron temperature Te ≤ 3 eV at the outer strike point (OSP). With toroidal field such that radial E × B drift carries particles from the OSP towards the private flux region (PFR), placing the OSP near the inner slot wall gives ≈20% lower UDD than having the OSP near the outer wall. The inner wall effectively traps the radial E × B drift flux, resulting in low Te and associated radial electric field in the PFR, and thus small losses from the slot to the inner target via poloidal E × B drift flux. With toroidal field reversed such that radial E × B drift is reversed, OSP placement near the inner wall gives ≈10% lower UDD than OSP placement near the outer wall. Although radial E × B flux is from the OSP towards the outer wall, this flux largely escapes the slot, raising the UDD. Finally, a change in the slot shaping is suggested with the goal of eliminating such E × B-driven particle losses from the slot.},
doi = {10.1002/ctpp.201900151},
journal = {Contributions to Plasma Physics},
number = 5-6,
volume = 60,
place = {United States},
year = {2020},
month = {2}
}
Works referenced in this record:
Detailed comparison of simulated and measured plasma profiles in the scrape-off layer and edge plasma of DIII-D
journal, September 2000
- Porter, G. D.; Isler, R.; Boedo, J.
- Physics of Plasmas, Vol. 7, Issue 9
Influence of and ∇B drift terms in 2-D edge/SOL transport simulations
journal, March 1999
- Rognlien, T. D.; Porter, G. D.; Ryutov, D. D.
- Journal of Nuclear Materials, Vol. 266-269
Effects of divertor geometry on tokamak plasmas
journal, May 2001
- Loarte, Alberto
- Plasma Physics and Controlled Fusion, Vol. 43, Issue 6
Interpretations of the impact of cross-field drifts on divertor flows in DIII-D with UEDGE
journal, August 2017
- Jaervinen, A. E.; Allen, S. L.; Groth, M.
- Nuclear Materials and Energy, Vol. 12
Plasma detachment in divertor tokamaks
journal, February 2018
- Leonard, A. W.
- Plasma Physics and Controlled Fusion, Vol. 60, Issue 4
Analytic description of the chemical erosion of graphite by hydrogen ions
journal, December 1996
- Roth, J.; Garcia-Rosales, C.
- Nuclear Fusion, Vol. 36, Issue 12
The new SOLPS-ITER code package
journal, August 2015
- Wiesen, S.; Reiter, D.; Kotov, V.
- Journal of Nuclear Materials, Vol. 463
Inter-ELM Power Decay Length for JET and ASDEX Upgrade: Measurement and Comparison with Heuristic Drift-Based Model
journal, November 2011
- Eich, T.; Sieglin, B.; Scarabosio, A.
- Physical Review Letters, Vol. 107, Issue 21
The effect of neutrals in the new SAS divertor at DIII-D as modelled by SOLPS
journal, May 2019
- Casali, L.; Covele, B. M.; Guo, H. Y.
- Nuclear Materials and Energy, Vol. 19
Divertor leg filaments in NSTX-U
journal, October 2018
- Scotti, Filippo; Zweben, Stewart; Soukhanovskii, Vlad
- Nuclear Fusion, Vol. 58, Issue 12
Modeling of detachment experiments at DIII-D
journal, August 2015
- Canik, J. M.; Briesemeister, A. R.; Lasnier, C. J.
- Journal of Nuclear Materials, Vol. 463
Comparison of 2D simulations of detached divertor plasmas with divertor Thomson measurements in the DIII-D tokamak
journal, August 2017
- Rognlien, T. D.; McLean, A. G.; Fenstermacher, M. E.
- Nuclear Materials and Energy, Vol. 12
Fast imaging of filaments in the X-point region of Alcator C-Mod
journal, August 2017
- Terry, J. L.; Ballinger, S.; Brunner, D.
- Nuclear Materials and Energy, Vol. 12
Scaling of the tokamak near the scrape-off layer H-mode power width and implications for ITER
journal, August 2013
- Eich, T.; Leonard, A. W.; Pitts, R. A.
- Nuclear Fusion, Vol. 53, Issue 9
Presentation of the New SOLPS-ITER Code Package for Tokamak Plasma Edge Modelling
journal, January 2016
- Bonnin, Xavier; Dekeyser, Wouter; Pitts, Richard
- Plasma and Fusion Research, Vol. 11, Issue 0
Tokamak plasma edge modelling including the main chamber wall
journal, July 2011
- Baelmans, M.; Börner, P.; Dekeyser, W.
- Nuclear Fusion, Vol. 51, Issue 8
Electron pressure balance in the SOL through the transition to detachment
journal, August 2015
- McLean, A. G.; Leonard, A. W.; Makowski, M. A.
- Journal of Nuclear Materials, Vol. 463
A review of direct experimental measurements of detachment
journal, February 2018
- Boedo, J.; McLean, A. G.; Rudakov, D. L.
- Plasma Physics and Controlled Fusion, Vol. 60, Issue 4
Drift effects and up-down asymmetry in balanced double-null DIII-D divertor configurations
journal, June 2018
- Meier, E. T.; Covele, B.; Guo, H. Y.
- Contributions to Plasma Physics, Vol. 58, Issue 6-8
SOLPS analysis of neutral baffling for the design of a new diverter in DIII-D
journal, April 2017
- Sang, Chaofeng; Guo, H. Y.; Stangeby, P. C.
- Nuclear Fusion, Vol. 57, Issue 5
A design study for an advanced divertor for DIII-D and ITER: the radiative slot divertor
journal, December 1992
- Allen, S. L.; Rensink, M. E.; Hill, D. N.
- Journal of Nuclear Materials, Vol. 196-198
Divertor Physics Research on Alcator C-Mod
journal, April 2007
- Lipschultz, B.; LaBombard, B.; Terry, J. L.
- Fusion Science and Technology, Vol. 51, Issue 3
Filamentary transport in the private flux region in MAST
journal, August 2015
- Harrison, J. R.; Fishpool, G. M.; Dudson, B. D.
- Journal of Nuclear Materials, Vol. 463
Radiative divertor and scrape-off layer experiments in open and baffled divertors on DIII-D
journal, November 1999
- Allen, S. L.; Brooks, N. H.; Bastasz, R.
- Nuclear Fusion, Vol. 39, Issue 11Y
First experimental tests of a new small angle slot divertor on DIII-D
journal, July 2019
- Guo, H. Y.; Wang, H. Q.; Watkins, J. G.
- Nuclear Fusion, Vol. 59, Issue 8
Two-point analysis of the numerical modelling of detached divertor plasmas
journal, October 2009
- Kotov, V.; Reiter, D.
- Plasma Physics and Controlled Fusion, Vol. 51, Issue 11
Drifts, currents, and power scrape-off width in SOLPS-ITER modeling of DIII-D
journal, August 2017
- Meier, E. T.; Goldston, R. J.; Kaveeva, E. G.
- Nuclear Materials and Energy, Vol. 12
Electric field-induced plasma convection in tokamak divertors
journal, April 2000
- Boedo, J. A.; Schaffer, M. J.; Maingi, R.
- Physics of Plasmas, Vol. 7, Issue 4