Sensitivity of the Boundary Plasma to the Plasma-Material Interface

Canik, John M.; Tang, X. -Z.

doi:10.13182/FST16-124

Title: Sensitivity of the Boundary Plasma to the Plasma-Material Interface

Abstract

While the sensitivity of the scrape-off layer and divertor plasma to the highly uncertain cross-field transport assumptions is widely recognized, the plasma is also sensitive to the details of the plasma-material interface (PMI) models used as part of comprehensive predictive simulations. Here in this paper, these PMI sensitivities are studied by varying the relevant sub-models within the SOLPS plasma transport code. Two aspects are explored: the sheath model used as a boundary condition in SOLPS, and fast particle reflection rates for ions impinging on a material surface. Both of these have been the study of recent high-fidelity simulation efforts aimed at improving the understanding and prediction of these phenomena. It is found that in both cases quantitative changes to the plasma solution result from modification of the PMI model, with a larger impact in the case of the reflection coefficient variation. Finally, this indicates the necessity to better quantify the uncertainties within the PMI models themselves, and perform thorough sensitivity analysis to propagate these throughout the boundary model; this is especially important for validation against experiment, where the error in the simulation is a critical and less-studied piece of the code-experiment comparison.

Authors:

Canik, John M. ^[1]; Tang, X. -Z. ^[2]

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Publication Date:: Sun Jan 01 00:00:00 EST 2017

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE Office of Science (SC)

OSTI Identifier:: 1341530

Grant/Contract Number:: AC05-00OR22725; AC52-06NA25396

Resource Type:: Accepted Manuscript

Journal Name:: Fusion Science and Technology

Additional Journal Information:: Journal Volume: 71; Journal Issue: 1; Journal ID: ISSN 1536-1055

Publisher:: American Nuclear Society

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Scrape-off layer; divertor; sheath

Citation Formats


                    Canik, John M., and Tang, X. -Z. Sensitivity of the Boundary Plasma to the Plasma-Material Interface.  United States: N. p., 2017. 
Web.  doi:10.13182/FST16-124.

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                    Canik, John M., & Tang, X. -Z. Sensitivity of the Boundary Plasma to the Plasma-Material Interface.  United States.  https://doi.org/10.13182/FST16-124

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                    Canik, John M., and Tang, X. -Z. Sun .  
"Sensitivity of the Boundary Plasma to the Plasma-Material Interface".  United States.  https://doi.org/10.13182/FST16-124.  https://www.osti.gov/servlets/purl/1341530.

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@article{osti_1341530,

  title        = {Sensitivity of the Boundary Plasma to the Plasma-Material Interface},

  author       = {Canik, John M. and Tang, X. -Z.},

  abstractNote = {While the sensitivity of the scrape-off layer and divertor plasma to the highly uncertain cross-field transport assumptions is widely recognized, the plasma is also sensitive to the details of the plasma-material interface (PMI) models used as part of comprehensive predictive simulations. Here in this paper, these PMI sensitivities are studied by varying the relevant sub-models within the SOLPS plasma transport code. Two aspects are explored: the sheath model used as a boundary condition in SOLPS, and fast particle reflection rates for ions impinging on a material surface. Both of these have been the study of recent high-fidelity simulation efforts aimed at improving the understanding and prediction of these phenomena. It is found that in both cases quantitative changes to the plasma solution result from modification of the PMI model, with a larger impact in the case of the reflection coefficient variation. Finally, this indicates the necessity to better quantify the uncertainties within the PMI models themselves, and perform thorough sensitivity analysis to propagate these throughout the boundary model; this is especially important for validation against experiment, where the error in the simulation is a critical and less-studied piece of the code-experiment comparison.},

  doi          = {10.13182/FST16-124},

  journal      = {Fusion Science and Technology},

  number       = 1,

  volume       = 71,

  place        = {United States},

  year         = {Sun Jan 01 00:00:00 EST 2017},

  month        = {Sun Jan 01 00:00:00 EST 2017}

}

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Works referenced in this record:

Consequences of a reduction of the upstream power SOL width in ITER
journal, July 2013

Kukushkin, A. S.; Pacher, H. D.; Pacher, G. W.
Journal of Nuclear Materials, Vol. 438
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Obtaining reactor-relevant divertor conditions in tokamaks
journal, April 2011

Stangeby, P. C.; Leonard, A. W.
Nuclear Fusion, Vol. 51, Issue 6
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Multi-Fluid Modeling of Large Parallel Plasma Flows in the Tokamak Scrape-Off Layer
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Pigarov, A. Yu.; Krasheninnikov, S. I.; LaBombard, B.
Contributions to Plasma Physics, Vol. 46, Issue 7-9
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Influence of and ∇B drift terms in 2-D edge/SOL transport simulations
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Rognlien, T. D.; Porter, G. D.; Ryutov, D. D.
Journal of Nuclear Materials, Vol. 266-269
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The relation between upstream density and temperature widths in the scrape-off layer and the power width in an attached divertor
journal, November 2010

Stangeby, P. C.; Canik, J. M.; Whyte, D. G.
Nuclear Fusion, Vol. 50, Issue 12
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Dependence of divertor heat flux widths on heating power, flux expansion, and plasma current in the NSTX
journal, August 2011

Gray, T. K.; Maingi, R.; Soukhanovskii, V. A.
Journal of Nuclear Materials, Vol. 415, Issue 1
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Plasma–wall transition in an oblique magnetic field
journal, January 1982

Chodura, R.
Physics of Fluids, Vol. 25, Issue 9
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Sheath energy transmission in a collisional plasma with collisionless sheath
journal, October 2015

Tang, Xian-Zhu; Guo, Zehua
Physics of Plasmas, Vol. 22, Issue 10
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Data sets for hydrogen reflection and their use in neutral transport calculations
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Eckstein, W.; Heifetz, D. B.
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Reflection and implantation of low energy helium with tungsten surfaces
journal, April 2014

Borovikov, Valery; Voter, Arthur F.; Tang, Xian-Zhu
Journal of Nuclear Materials, Vol. 447, Issue 1-3
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Analysis of a multi-machine database on divertor heat fluxes
journal, May 2012

Makowski, M. A.; Elder, D.; Gray, T. K.
Physics of Plasmas, Vol. 19, Issue 5
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ELM energy scaling in DIII-D
journal, May 2002

Leonard, A. W.; Groebner, R. J.; Mahdavi, M. A.
Plasma Physics and Controlled Fusion, Vol. 44, Issue 6
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Key ITER plasma edge and plasma–material interaction issues
journal, March 2003

Federici, G.; Andrew, P.; Barabaschi, P.
Journal of Nuclear Materials, Vol. 313-316
DOI: 10.1016/S0022-3115(02)01327-2

The Multi-Fluid Codes Edgeid and Edge2D: Models and Results
journal, January 1992

Taroni, A.; Corrigan, G.; Radford, G.
Contributions to Plasma Physics, Vol. 32, Issue 3-4
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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
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Divertor heat flux footprints in EDA H-mode discharges on Alcator C-Mod
journal, August 2011

LaBombard, B.; Terry, J. L.; Hughes, J. W.
Journal of Nuclear Materials, Vol. 415, Issue 1
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Ultrahigh performance three-dimensional electromagnetic relativistic kinetic plasma simulation
journal, May 2008

Bowers, K. J.; Albright, B. J.; Yin, L.
Physics of Plasmas, Vol. 15, Issue 5
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Comparison of H-mode plasmas in JET-ILW and JET-C with and without nitrogen seeding
journal, March 2016

Jaervinen, A. E.; Giroud, C.; Groth, M.
Nuclear Fusion, Vol. 56, Issue 4
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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
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The EIRENE and B2-EIRENE Codes
journal, February 2005

Reiter, D.; Baelmans, M.; Börner, P.
Fusion Science and Technology, Vol. 47, Issue 2
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Plasma Edge Physics with B2-Eirene
journal, February 2006

Schneider, R.; Bonnin, X.; Borrass, K.
Contributions to Plasma Physics, Vol. 46, Issue 1-2
DOI: 10.1002/ctpp.200610001

Works referencing / citing this record:

Plasma Power Recycling at the Divertor Surface
journal, January 2017

Tang, Xian-Zhu; Guo, Zehua
Fusion Science and Technology, Vol. 71, Issue 1
DOI: 10.13182/fst16-119

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Similar Records

Title: Sensitivity of the Boundary Plasma to the Plasma-Material Interface

Abstract

Citation Formats

Consequences of a reduction of the upstream power SOL width in ITER journal, July 2013

Obtaining reactor-relevant divertor conditions in tokamaks journal, April 2011

Multi-Fluid Modeling of Large Parallel Plasma Flows in the Tokamak Scrape-Off Layer journal, September 2006

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

The relation between upstream density and temperature widths in the scrape-off layer and the power width in an attached divertor journal, November 2010

Dependence of divertor heat flux widths on heating power, flux expansion, and plasma current in the NSTX journal, August 2011

Plasma–wall transition in an oblique magnetic field journal, January 1982

Sheath energy transmission in a collisional plasma with collisionless sheath journal, October 2015

Data sets for hydrogen reflection and their use in neutral transport calculations journal, February 1987

Reflection and implantation of low energy helium with tungsten surfaces journal, April 2014

Analysis of a multi-machine database on divertor heat fluxes journal, May 2012

ELM energy scaling in DIII-D journal, May 2002

Key ITER plasma edge and plasma–material interaction issues journal, March 2003

The Multi-Fluid Codes Edgeid and Edge2D: Models and Results journal, January 1992

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

Divertor heat flux footprints in EDA H-mode discharges on Alcator C-Mod journal, August 2011

Ultrahigh performance three-dimensional electromagnetic relativistic kinetic plasma simulation journal, May 2008

Comparison of H-mode plasmas in JET-ILW and JET-C with and without nitrogen seeding journal, March 2016

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

The EIRENE and B2-EIRENE Codes journal, February 2005

Plasma Edge Physics with B2-Eirene journal, February 2006

Plasma Power Recycling at the Divertor Surface journal, January 2017

Consequences of a reduction of the upstream power SOL width in ITER
journal, July 2013

Obtaining reactor-relevant divertor conditions in tokamaks
journal, April 2011

Multi-Fluid Modeling of Large Parallel Plasma Flows in the Tokamak Scrape-Off Layer
journal, September 2006

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

The relation between upstream density and temperature widths in the scrape-off layer and the power width in an attached divertor
journal, November 2010

Dependence of divertor heat flux widths on heating power, flux expansion, and plasma current in the NSTX
journal, August 2011

Plasma–wall transition in an oblique magnetic field
journal, January 1982

Sheath energy transmission in a collisional plasma with collisionless sheath
journal, October 2015

Data sets for hydrogen reflection and their use in neutral transport calculations
journal, February 1987

Reflection and implantation of low energy helium with tungsten surfaces
journal, April 2014

Analysis of a multi-machine database on divertor heat fluxes
journal, May 2012

ELM energy scaling in DIII-D
journal, May 2002

Key ITER plasma edge and plasma–material interaction issues
journal, March 2003

The Multi-Fluid Codes Edgeid and Edge2D: Models and Results
journal, January 1992

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

Divertor heat flux footprints in EDA H-mode discharges on Alcator C-Mod
journal, August 2011

Ultrahigh performance three-dimensional electromagnetic relativistic kinetic plasma simulation
journal, May 2008

Comparison of H-mode plasmas in JET-ILW and JET-C with and without nitrogen seeding
journal, March 2016

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

The EIRENE and B2-EIRENE Codes
journal, February 2005

Plasma Edge Physics with B2-Eirene
journal, February 2006

Plasma Power Recycling at the Divertor Surface
journal, January 2017