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

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 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 towardsmore »« less

Authors:

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)
General Atomics, San Diego, CA (United States)

Publication Date:: Sat Feb 15 00:00:00 EST 2020

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:: Journal Article: 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.

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                    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

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                    Meier, E. T., Covele, B. M., Guo, H. Y., Leonard, A. W., and Thomas, D. M. 2020.  
        "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.

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@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},

  url          = {https://www.osti.gov/biblio/1601921},
  journal      = {Contributions to Plasma Physics},

  issn         = {0863-1042},

  number       = 5-6,

  volume       = 60,

  place        = {United States},

  year         = {Sat Feb 15 00:00:00 EST 2020},

  month        = {Sat Feb 15 00:00:00 EST 2020}

}

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Similar Records

Title: Modeling ExB drift transport in conceptual slot divertor configurations

Abstract

Citation Formats

Detailed comparison of simulated and measured plasma profiles in the scrape-off layer and edge plasma of DIII-D journal, September 2000

Influence of and ∇B drift terms in 2-D edge/SOL transport simulations journal, March 1999

Effects of divertor geometry on tokamak plasmas journal, May 2001

Interpretations of the impact of cross-field drifts on divertor flows in DIII-D with UEDGE journal, August 2017

Plasma detachment in divertor tokamaks journal, February 2018

Analytic description of the chemical erosion of graphite by hydrogen ions journal, December 1996

The new SOLPS-ITER code package journal, August 2015

Inter-ELM Power Decay Length for JET and ASDEX Upgrade: Measurement and Comparison with Heuristic Drift-Based Model journal, November 2011

The effect of neutrals in the new SAS divertor at DIII-D as modelled by SOLPS journal, May 2019

Divertor leg filaments in NSTX-U journal, October 2018

Modeling of detachment experiments at DIII-D journal, August 2015

Comparison of 2D simulations of detached divertor plasmas with divertor Thomson measurements in the DIII-D tokamak journal, August 2017

Fast imaging of filaments in the X-point region of Alcator C-Mod journal, August 2017

Scaling of the tokamak near the scrape-off layer H-mode power width and implications for ITER journal, August 2013

Presentation of the New SOLPS-ITER Code Package for Tokamak Plasma Edge Modelling journal, January 2016

Tokamak plasma edge modelling including the main chamber wall journal, July 2011

Electron pressure balance in the SOL through the transition to detachment journal, August 2015

A review of direct experimental measurements of detachment journal, February 2018

Drift effects and up-down asymmetry in balanced double-null DIII-D divertor configurations journal, June 2018

SOLPS analysis of neutral baffling for the design of a new diverter in DIII-D journal, April 2017

A design study for an advanced divertor for DIII-D and ITER: the radiative slot divertor journal, December 1992

Divertor Physics Research on Alcator C-Mod journal, April 2007

Filamentary transport in the private flux region in MAST journal, August 2015

Radiative divertor and scrape-off layer experiments in open and baffled divertors on DIII-D journal, November 1999

First experimental tests of a new small angle slot divertor on DIII-D journal, July 2019

Two-point analysis of the numerical modelling of detached divertor plasmas journal, October 2009

Drifts, currents, and power scrape-off width in SOLPS-ITER modeling of DIII-D journal, August 2017

Electric field-induced plasma convection in tokamak divertors journal, April 2000

Detailed comparison of simulated and measured plasma profiles in the scrape-off layer and edge plasma of DIII-D
journal, September 2000

Influence of and ∇B drift terms in 2-D edge/SOL transport simulations
journal, March 1999

Effects of divertor geometry on tokamak plasmas
journal, May 2001

Interpretations of the impact of cross-field drifts on divertor flows in DIII-D with UEDGE
journal, August 2017

Plasma detachment in divertor tokamaks
journal, February 2018

Analytic description of the chemical erosion of graphite by hydrogen ions
journal, December 1996

The new SOLPS-ITER code package
journal, August 2015

Inter-ELM Power Decay Length for JET and ASDEX Upgrade: Measurement and Comparison with Heuristic Drift-Based Model
journal, November 2011

The effect of neutrals in the new SAS divertor at DIII-D as modelled by SOLPS
journal, May 2019

Divertor leg filaments in NSTX-U
journal, October 2018

Modeling of detachment experiments at DIII-D
journal, August 2015

Comparison of 2D simulations of detached divertor plasmas with divertor Thomson measurements in the DIII-D tokamak
journal, August 2017

Fast imaging of filaments in the X-point region of Alcator C-Mod
journal, August 2017

Scaling of the tokamak near the scrape-off layer H-mode power width and implications for ITER
journal, August 2013

Presentation of the New SOLPS-ITER Code Package for Tokamak Plasma Edge Modelling
journal, January 2016

Tokamak plasma edge modelling including the main chamber wall
journal, July 2011

Electron pressure balance in the SOL through the transition to detachment
journal, August 2015

A review of direct experimental measurements of detachment
journal, February 2018

Drift effects and up-down asymmetry in balanced double-null DIII-D divertor configurations
journal, June 2018

SOLPS analysis of neutral baffling for the design of a new diverter in DIII-D
journal, April 2017

A design study for an advanced divertor for DIII-D and ITER: the radiative slot divertor
journal, December 1992

Divertor Physics Research on Alcator C-Mod
journal, April 2007

Filamentary transport in the private flux region in MAST
journal, August 2015

Radiative divertor and scrape-off layer experiments in open and baffled divertors on DIII-D
journal, November 1999

First experimental tests of a new small angle slot divertor on DIII-D
journal, July 2019

Two-point analysis of the numerical modelling of detached divertor plasmas
journal, October 2009

Drifts, currents, and power scrape-off width in SOLPS-ITER modeling of DIII-D
journal, August 2017

Electric field-induced plasma convection in tokamak divertors
journal, April 2000