Transport of tungsten to collector probes in DIII-D

Zamperini, Shawn A.; Donovan, David C.; Unterberg, Ezekial; Stangeby, Peter; Nichols, Jacob H.; Duran, Jonah D.; Elder, D.; Neff, Anton; Rudakov, D. L.; Zach, Mike

doi:10.1016/j.nme.2018.12.013

Title: Transport of tungsten to collector probes in DIII-D

Abstract

Collector Probes have long been used to measure impurity fluxes in the scrape off layer (SOL) of tokamaks. In this study, collector probes were inserted in the main SOL of DIII-D during the tungsten Metal Rings Campaign, and the W deposits on the probes were analyzed ex-situ using Rutherford backscattering spectrometry analysis to obtain radial profiles of W deposition. A simple picture is hypothesized for how the W transports through the SOL from the target to the two sides of the probe, based on a long-theorized impurity accumulation at the crown (i.e. the top) of the plasma. The patterns observed in the deposition profiles along the probes support the hypothesized picture; however, 3D modeling and further experimental studies are needed to support more definitive conclusions.

Authors:

^[1]; Donovan, David C. ^[1];

^[2]; Stangeby, Peter ^[3]; Nichols, Jacob H. ^[1];

^[1];

^[3]; Neff, Anton ^[2]; Rudakov, D. L. ^[4];

^[2]

Univ. of Tennessee, Knoxville, TN (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Univ. of Toronto Inst. for Aerospace Studies (UTIAS), Toronto, ON (Canada)
Univ. of California, San Diego (UCSD), San Diego, CA (United State)

Publication Date:: Thu Dec 13 00:00:00 EST 2018

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Contributing Org.:: Oak Ridge National Laboratory University of Toronto University of California-San Diego Sandia National Laboratory

OSTI Identifier:: 1530109

Alternate Identifier(s):: OSTI ID: 1737360

Grant/Contract Number:: AC05-00OR22725; SC0019256

Resource Type:: Accepted Manuscript

Journal Name:: Nuclear Materials and Energy

Additional Journal Information:: Journal Volume: 18; Journal Issue: C; Journal ID: ISSN 2352-1791

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Impurity, Scrape-off Layer, Tokamak, Plasma-Material Interactions, PMI, Tungsten, DIII-D

Citation Formats


                    Zamperini, Shawn A., Donovan, David C., Unterberg, Ezekial, Stangeby, Peter, Nichols, Jacob H., Duran, Jonah D., Elder, D., Neff, Anton, Rudakov, D. L., and Zach, Mike. Transport of tungsten to collector probes in DIII-D.  United States: N. p., 2018. 
Web.  doi:10.1016/j.nme.2018.12.013.

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                    Zamperini, Shawn A., Donovan, David C., Unterberg, Ezekial, Stangeby, Peter, Nichols, Jacob H., Duran, Jonah D., Elder, D., Neff, Anton, Rudakov, D. L., & Zach, Mike. Transport of tungsten to collector probes in DIII-D.  United States.  https://doi.org/10.1016/j.nme.2018.12.013

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                    Zamperini, Shawn A., Donovan, David C., Unterberg, Ezekial, Stangeby, Peter, Nichols, Jacob H., Duran, Jonah D., Elder, D., Neff, Anton, Rudakov, D. L., and Zach, Mike. Thu .  
"Transport of tungsten to collector probes in DIII-D".  United States.  https://doi.org/10.1016/j.nme.2018.12.013.  https://www.osti.gov/servlets/purl/1530109.

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@article{osti_1530109,

  title        = {Transport of tungsten to collector probes in DIII-D},

  author       = {Zamperini, Shawn A. and Donovan, David C. and Unterberg, Ezekial and Stangeby, Peter and Nichols, Jacob H. and Duran, Jonah D. and Elder, D. and Neff, Anton and Rudakov, D. L. and Zach, Mike},

  abstractNote = {Collector Probes have long been used to measure impurity fluxes in the scrape off layer (SOL) of tokamaks. In this study, collector probes were inserted in the main SOL of DIII-D during the tungsten Metal Rings Campaign, and the W deposits on the probes were analyzed ex-situ using Rutherford backscattering spectrometry analysis to obtain radial profiles of W deposition. A simple picture is hypothesized for how the W transports through the SOL from the target to the two sides of the probe, based on a long-theorized impurity accumulation at the crown (i.e. the top) of the plasma. The patterns observed in the deposition profiles along the probes support the hypothesized picture; however, 3D modeling and further experimental studies are needed to support more definitive conclusions.},

  doi          = {10.1016/j.nme.2018.12.013},

  journal      = {Nuclear Materials and Energy},

  number       = C,

  volume       = 18,

  place        = {United States},

  year         = {Thu Dec 13 00:00:00 EST 2018},

  month        = {Thu Dec 13 00:00:00 EST 2018}

}

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Journal Article:

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https://doi.org/10.1016/j.nme.2018.12.013

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Cited by: 9 works

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Figures / Tables:

Figure 1: Poloidal cross-section of DIII-D and an image of the collector probe assembly showing the insertion location.

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Works referenced in this record:

Status and physics basis of the ITER divertor
journal, December 2009

Pitts, R. A.; Kukushkin, A.; Loarte, A.
Physica Scripta, Vol. T138
DOI: 10.1088/0031-8949/2009/T138/014001

Overview of wall probes for erosion and deposition studies in the TEXTOR tokamak
journal, May 2017

Rubel, M.; Brezinsek, S.; Coenen, J. W.
Matter and Radiation at Extremes, Vol. 2, Issue 3
DOI: 10.1016/j.mre.2017.03.002

Ion flux measurements with the improved collector probe system at the TEXTOR-94 tokamak
journal, July 1998

Larsson, D.; Rubel, M.
Review of Scientific Instruments, Vol. 69, Issue 7
DOI: 10.1063/1.1148996

The Design and Use of Tungsten Coated TZM Molybdenum Tile Inserts in the DIII-D Tokamak Divertor
journal, August 2017

Holtrop, K.; Buchenauer, D.; Chrobak, C.
Fusion Science and Technology, Vol. 72, Issue 4
DOI: 10.1080/15361055.2017.1347456

Use of isotopic tungsten tracers and a stable-isotope-mixing model to characterize divertor source location in the DIII-D metal rings campaign
journal, May 2019

Unterberg, E. A.; Donovan, D. C.; Duran, J. D.
Nuclear Materials and Energy, Vol. 19
DOI: 10.1016/j.nme.2019.02.028

Interpretation of plasma impurity deposition probes. Analytic approximation
journal, January 1987

Stangeby, P. C.
Physics of Fluids, Vol. 30, Issue 10
DOI: 10.1063/1.866502

Measuring plasma drift velocities in tokamak edge plasmas using probes
journal, January 1984

Stangeby, P. C.
Physics of Fluids, Vol. 27, Issue 11
DOI: 10.1063/1.864573

Utilization of outer-midplane collector probes with isotopically enriched tungsten tracer particles for impurity transport studies in the scrape-off layer of DIII-D (invited)
journal, October 2018

Donovan, D. C.; Unterberg, E. A.; Stangeby, P. C.
Review of Scientific Instruments, Vol. 89, Issue 10
DOI: 10.1063/1.5039347

The magnitude of plasma flux to the main-wall in the DIII-D tokamak
journal, September 2005

Whyte, D. G.; Lipschultz, B. L.; Stangeby, P. C.
Plasma Physics and Controlled Fusion, Vol. 47, Issue 10
DOI: 10.1088/0741-3335/47/10/002

Modelling of impurity flow in the tokamak scrape-off layer
journal, January 1984

Neuhauser, J.; Schneider, W.; Wunderlich, R.
Nuclear Fusion, Vol. 24, Issue 1
DOI: 10.1088/0029-5515/24/1/004

The inter-ELM tungsten erosion profile in DIII-D H-mode discharges and benchmarking with ERO+OEDGE modeling
journal, April 2017

Abrams, T.; Ding, R.; Guo, H. Y.
Nuclear Fusion, Vol. 57, Issue 5
DOI: 10.1088/1741-4326/aa66b2

Evidence of near-SOL tungsten accumulation using a far-SOL collector probe array and OEDGE modelling in the DIII-D metal rings L-mode discharges
journal, May 2019

Elder, J. D.; Stangeby, P. C.; Unterberg, E. A.
Nuclear Materials and Energy, Vol. 19
DOI: 10.1016/j.nme.2019.03.007

Monte Carlo modelling of impurity ion transport for a limiter source/sink
journal, November 1988

Stangeby, P. C.; Farrell, C.; Hoskins, S.
Nuclear Fusion, Vol. 28, Issue 11
DOI: 10.1088/0029-5515/28/11/003

Impurity transport at the plasma edge
journal, December 1990

Stangeby, P. C.
Journal of Nuclear Materials, Vol. 176-177
DOI: 10.1016/0022-3115(90)90028-L

Modelling of beryllium erosion–redeposition on ITER first wall panels
journal, August 2011

Carpentier, S.; Pitts, R. A.; Stangeby, P. C.
Journal of Nuclear Materials, Vol. 415, Issue 1
DOI: 10.1016/j.jnucmat.2010.10.081

Measurements of ion energies in the tokamak plasma boundary
journal, August 2011

Kočan, M.; Gunn, J. P.; Carpentier-Chouchana, S.
Journal of Nuclear Materials, Vol. 415, Issue 1
DOI: 10.1016/j.jnucmat.2010.08.036

Works referencing / citing this record:

Multiple Analytical Approach to Isotopic Transport Analysis in Magnetic Fusion Devices
journal, May 2019

Duran, Jonah D.; Unterberg, Ezekial A.; Zach, Mike P.
Fusion Science and Technology, Vol. 75, Issue 6
DOI: 10.1080/15361055.2019.1610316

Localized divertor leakage measurements using isotopic tungsten sources during edge-localized mode-y H-mode discharges on DIII-D
journal, November 2019

Unterberg, E. A.; Abrams, T.; Bykov, I.
Nuclear Fusion, Vol. 60, Issue 1
DOI: 10.1088/1741-4326/ab537b

Figures / Tables found in this record:

Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.

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Evidence of near-SOL tungsten accumulation using a far-SOL collector probe array and OEDGE modelling in the DIII-D metal rings L-mode discharges

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Similar Records

Title: Transport of tungsten to collector probes in DIII-D

Abstract

Citation Formats

Figures / Tables:

Status and physics basis of the ITER divertor journal, December 2009

Overview of wall probes for erosion and deposition studies in the TEXTOR tokamak journal, May 2017

Ion flux measurements with the improved collector probe system at the TEXTOR-94 tokamak journal, July 1998

The Design and Use of Tungsten Coated TZM Molybdenum Tile Inserts in the DIII-D Tokamak Divertor journal, August 2017

Use of isotopic tungsten tracers and a stable-isotope-mixing model to characterize divertor source location in the DIII-D metal rings campaign journal, May 2019

Interpretation of plasma impurity deposition probes. Analytic approximation journal, January 1987

Measuring plasma drift velocities in tokamak edge plasmas using probes journal, January 1984

Utilization of outer-midplane collector probes with isotopically enriched tungsten tracer particles for impurity transport studies in the scrape-off layer of DIII-D (invited) journal, October 2018

The magnitude of plasma flux to the main-wall in the DIII-D tokamak journal, September 2005

Modelling of impurity flow in the tokamak scrape-off layer journal, January 1984

The inter-ELM tungsten erosion profile in DIII-D H-mode discharges and benchmarking with ERO+OEDGE modeling journal, April 2017

Evidence of near-SOL tungsten accumulation using a far-SOL collector probe array and OEDGE modelling in the DIII-D metal rings L-mode discharges journal, May 2019

Monte Carlo modelling of impurity ion transport for a limiter source/sink journal, November 1988

Impurity transport at the plasma edge journal, December 1990

Modelling of beryllium erosion–redeposition on ITER first wall panels journal, August 2011

Measurements of ion energies in the tokamak plasma boundary journal, August 2011

Multiple Analytical Approach to Isotopic Transport Analysis in Magnetic Fusion Devices journal, May 2019

Localized divertor leakage measurements using isotopic tungsten sources during edge-localized mode-y H-mode discharges on DIII-D journal, November 2019

Status and physics basis of the ITER divertor
journal, December 2009

Overview of wall probes for erosion and deposition studies in the TEXTOR tokamak
journal, May 2017

Ion flux measurements with the improved collector probe system at the TEXTOR-94 tokamak
journal, July 1998

The Design and Use of Tungsten Coated TZM Molybdenum Tile Inserts in the DIII-D Tokamak Divertor
journal, August 2017

Use of isotopic tungsten tracers and a stable-isotope-mixing model to characterize divertor source location in the DIII-D metal rings campaign
journal, May 2019

Interpretation of plasma impurity deposition probes. Analytic approximation
journal, January 1987

Measuring plasma drift velocities in tokamak edge plasmas using probes
journal, January 1984

Utilization of outer-midplane collector probes with isotopically enriched tungsten tracer particles for impurity transport studies in the scrape-off layer of DIII-D (invited)
journal, October 2018

The magnitude of plasma flux to the main-wall in the DIII-D tokamak
journal, September 2005

Modelling of impurity flow in the tokamak scrape-off layer
journal, January 1984

The inter-ELM tungsten erosion profile in DIII-D H-mode discharges and benchmarking with ERO+OEDGE modeling
journal, April 2017

Evidence of near-SOL tungsten accumulation using a far-SOL collector probe array and OEDGE modelling in the DIII-D metal rings L-mode discharges
journal, May 2019

Monte Carlo modelling of impurity ion transport for a limiter source/sink
journal, November 1988

Impurity transport at the plasma edge
journal, December 1990

Modelling of beryllium erosion–redeposition on ITER first wall panels
journal, August 2011

Measurements of ion energies in the tokamak plasma boundary
journal, August 2011

Multiple Analytical Approach to Isotopic Transport Analysis in Magnetic Fusion Devices
journal, May 2019

Localized divertor leakage measurements using isotopic tungsten sources during edge-localized mode-y H-mode discharges on DIII-D
journal, November 2019