Modeling ExB drift transport in conceptual slot divertor configurations

Meier, E. T.; Covele, B. M.; Guo, H. Y.; Leonard, A. W.; Thomas, D. M.

doi:10.1002/ctpp.201900151

Title: Modeling ExB drift transport in conceptual slot divertor configurations

Journal Article · 14 February 2020 · Contributions to Plasma Physics

DOI: https://doi.org/10.1002/ctpp.201900151 · OSTI ID:1601921

Meier, E. T. ^[1]; Covele, B. M. ^[2]; Guo, H. Y. ^[2]; Leonard, A. W. ^[2]; Thomas, D. M. ^[2]

Univ. of Washington, Seattle, WA (United States); N/A
General Atomics, San Diego, CA (United States)

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 T_e≤ 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 T_e 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.

View Accepted Manuscript (DOE)

Cite

Export

Save

Research Organization:: Univ. of Washington, Seattle, WA (United States)

Sponsoring Organization:: USDOE; USDOE Office of Energy Efficiency and Renewable Energy (EERE), Office of Technology Utilization (EE-34); USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)

Grant/Contract Number:: FC02-04ER54698; SC0019473

OSTI ID:: 1601921

Journal Information:: Contributions to Plasma Physics, Journal Name: Contributions to Plasma Physics Journal Issue: 5-6 Vol. 60; ISSN 0863-1042

Publisher:: WileyCopyright Statement

Country of Publication:: United States

Language:: English

References (28)

Drift effects and up-down asymmetry in balanced double-null DIII-D divertor configurations Meier, E. T.; Covele, B.; Guo, H. Y. Contributions to Plasma Physics, Vol. 58, Issue 6-8 https://doi.org/10.1002/ctpp.201700167	journal	June 2018
A design study for an advanced divertor for DIII-D and ITER: the radiative slot divertor Allen, S. L.; Rensink, M. E.; Hill, D. N. Journal of Nuclear Materials, Vol. 196-198 https://doi.org/10.1016/S0022-3115(06)80146-7	journal	December 1992
Influence of and ∇B drift terms in 2-D edge/SOL transport simulations Rognlien, T. D.; Porter, G. D.; Ryutov, D. D. Journal of Nuclear Materials, Vol. 266-269 https://doi.org/10.1016/S0022-3115(98)00835-6	journal	March 1999
The new SOLPS-ITER code package Wiesen, S.; Reiter, D.; Kotov, V. Journal of Nuclear Materials, Vol. 463 https://doi.org/10.1016/j.jnucmat.2014.10.012	journal	August 2015
Modeling of detachment experiments at DIII-D Canik, J. M.; Briesemeister, A. R.; Lasnier, C. J. Journal of Nuclear Materials, Vol. 463 https://doi.org/10.1016/j.jnucmat.2014.11.077	journal	August 2015
Filamentary transport in the private flux region in MAST Harrison, J. R.; Fishpool, G. M.; Dudson, B. D. Journal of Nuclear Materials, Vol. 463 https://doi.org/10.1016/j.jnucmat.2014.11.125	journal	August 2015
Electron pressure balance in the SOL through the transition to detachment McLean, A. G.; Leonard, A. W.; Makowski, M. A. Journal of Nuclear Materials, Vol. 463 https://doi.org/10.1016/j.jnucmat.2015.01.066	journal	August 2015
Interpretations of the impact of cross-field drifts on divertor flows in DIII-D with UEDGE Jaervinen, A. E.; Allen, S. L.; Groth, M. Nuclear Materials and Energy, Vol. 12 https://doi.org/10.1016/j.nme.2016.11.014	journal	August 2017
Fast imaging of filaments in the X-point region of Alcator C-Mod Terry, J. L.; Ballinger, S.; Brunner, D. Nuclear Materials and Energy, Vol. 12 https://doi.org/10.1016/j.nme.2016.11.020	journal	August 2017
Comparison of 2D simulations of detached divertor plasmas with divertor Thomson measurements in the DIII-D tokamak Rognlien, T. D.; McLean, A. G.; Fenstermacher, M. E. Nuclear Materials and Energy, Vol. 12 https://doi.org/10.1016/j.nme.2016.12.002	journal	August 2017
Drifts, currents, and power scrape-off width in SOLPS-ITER modeling of DIII-D Meier, E. T.; Goldston, R. J.; Kaveeva, E. G. Nuclear Materials and Energy, Vol. 12 https://doi.org/10.1016/j.nme.2016.12.016	journal	August 2017
The effect of neutrals in the new SAS divertor at DIII-D as modelled by SOLPS Casali, L.; Covele, B. M.; Guo, H. Y. Nuclear Materials and Energy, Vol. 19 https://doi.org/10.1016/j.nme.2019.03.021	journal	May 2019
Detailed comparison of simulated and measured plasma profiles in the scrape-off layer and edge plasma of DIII-D Porter, G. D.; Isler, R.; Boedo, J. Physics of Plasmas, Vol. 7, Issue 9 https://doi.org/10.1063/1.1286509	journal	September 2000
Electric field-induced plasma convection in tokamak divertors Boedo, J. A.; Schaffer, M. J.; Maingi, R. Physics of Plasmas, Vol. 7, Issue 4 https://doi.org/10.1063/1.873915	journal	April 2000
Analytic description of the chemical erosion of graphite by hydrogen ions Roth, J.; Garcia-Rosales, C. Nuclear Fusion, Vol. 36, Issue 12 https://doi.org/10.1088/0029-5515/36/12/I05	journal	December 1996
Radiative divertor and scrape-off layer experiments in open and baffled divertors on DIII-D Allen, S. L.; Brooks, N. H.; Bastasz, R. Nuclear Fusion, Vol. 39, Issue 11Y https://doi.org/10.1088/0029-5515/39/11Y/348	journal	November 1999
Tokamak plasma edge modelling including the main chamber wall Baelmans, M.; Börner, P.; Dekeyser, W. Nuclear Fusion, Vol. 51, Issue 8 https://doi.org/10.1088/0029-5515/51/8/083023	journal	July 2011
Scaling of the tokamak near the scrape-off layer H-mode power width and implications for ITER Eich, T.; Leonard, A. W.; Pitts, R. A. Nuclear Fusion, Vol. 53, Issue 9 https://doi.org/10.1088/0029-5515/53/9/093031	journal	August 2013
Effects of divertor geometry on tokamak plasmas Loarte, Alberto Plasma Physics and Controlled Fusion, Vol. 43, Issue 6 https://doi.org/10.1088/0741-3335/43/6/201	journal	May 2001
Two-point analysis of the numerical modelling of detached divertor plasmas Kotov, V.; Reiter, D. Plasma Physics and Controlled Fusion, Vol. 51, Issue 11 https://doi.org/10.1088/0741-3335/51/11/115002	journal	October 2009
A review of direct experimental measurements of detachment Boedo, J.; McLean, A. G.; Rudakov, D. L. Plasma Physics and Controlled Fusion, Vol. 60, Issue 4 https://doi.org/10.1088/1361-6587/aaa2ec	journal	February 2018
Plasma detachment in divertor tokamaks Leonard, A. W. Plasma Physics and Controlled Fusion, Vol. 60, Issue 4 https://doi.org/10.1088/1361-6587/aaa7a9	journal	February 2018
SOLPS analysis of neutral baffling for the design of a new diverter in DIII-D Sang, Chaofeng; Guo, H. Y.; Stangeby, P. C. Nuclear Fusion, Vol. 57, Issue 5 https://doi.org/10.1088/1741-4326/aa6548	journal	April 2017
Divertor leg filaments in NSTX-U Scotti, Filippo; Zweben, Stewart; Soukhanovskii, Vlad Nuclear Fusion, Vol. 58, Issue 12 https://doi.org/10.1088/1741-4326/aae49f	journal	October 2018
First experimental tests of a new small angle slot divertor on DIII-D Guo, H. Y.; Wang, H. Q.; Watkins, J. G. Nuclear Fusion, Vol. 59, Issue 8 https://doi.org/10.1088/1741-4326/ab26ee	journal	July 2019
Inter-ELM Power Decay Length for JET and ASDEX Upgrade: Measurement and Comparison with Heuristic Drift-Based Model Eich, T.; Sieglin, B.; Scarabosio, A. Physical Review Letters, Vol. 107, Issue 21 https://doi.org/10.1103/PhysRevLett.107.215001	journal	November 2011
Divertor Physics Research on Alcator C-Mod Lipschultz, B.; LaBombard, B.; Terry, J. L. Fusion Science and Technology, Vol. 51, Issue 3 https://doi.org/10.13182/FST07-A1428	journal	April 2007
Presentation of the New SOLPS-ITER Code Package for Tokamak Plasma Edge Modelling Bonnin, Xavier; Dekeyser, Wouter; Pitts, Richard Plasma and Fusion Research, Vol. 11, Issue 0 https://doi.org/10.1585/pfr.11.1403102	journal	January 2016

Similar Records

First evidence of dominant influence of E × B drifts on plasma cooling in an advanced slot divertor for tokamak power exhaust

Journal Article · 2021 · Nuclear Fusion · OSTI ID:1798817

Ma, Xinxing; Wang, Huiqian Q.; Guo, Houyang Y.; +4 more

E × B flow driven electron temperature bifurcation in a closed slot divertor with ion B × ∇B away from the X-point in the DIII-D tokamak

Journal Article · 2022 · Nuclear Fusion · OSTI ID:1895602

Ma, Xinxing; Wang, H. Q.; Guo, H. Y.; +10 more

Misalignment of magnetic field in DIII-D assessed by post-mortem analysis of divertor targets

Journal Article · 2022 · Nuclear Fusion · OSTI ID:1902578

Masline, R.; Bykov, I.; Moyer, R. A.; +7 more

Related Subjects

99 GENERAL AND MISCELLANEOUS
DIII-D
ExB drifts
SAS 2 slot divertor
SOLPS-ITER
detachment
divertor
modeling
plasma physics
tokamak

Title: Modeling ExB drift transport in conceptual slot divertor configurations

Citation Formats

References (28)

Similar Records

Related Subjects