skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

This content will become publicly available on November 11, 2020

Title: Reduced model of high-Z impurity redeposition and erosion in tokamak divertor and its application to DIII-D experiments

Abstract

A reduced model of high-Z impurities erosion and redeposition is presented to analyze net erosion of tungsten material in divertor attached plasma conditions measured in DIII-D experiments. This reduced model is tailored to quantify the redeposition and the net erosion on high-Z material samples of sufficiently small dimensions to be considered exposed to uniform plasma conditions. For those uniform plasma conditions, the spatial distribution of redeposited high-Z impurities is well approximated by an analytical distribution characterized by a few parameters. The fraction of high-Z impurity eroding and redepositing on a material sample is then obtained by integrating this distribution across the material sample. Here, the ratio of net erosion rates of tungsten measured experimentally from tungsten samples of different sizes exposed to the same attached plasma conditions are well reproduced with this reduced model. It is shown that uncertainties induced by radially non-uniform plasma conditions in experiments can be significantly reduced by exposing samples to high density divertor plasma. Several enhanced experimental setups are proposed to measure and compare net erosion rates from samples of various areas during a single plasma experiment.

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3];  [4];  [4];  [5]; ORCiD logo [4]
  1. Oak Ridge Associated Univ., Oak Ridge, TN (United States)
  2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
  3. Univ. of California San Diego, La Jolla, CA (United States)
  4. General Atomics, San Diego, CA (United States)
  5. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Research Org.:
General Atomics, San Diego, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
OSTI Identifier:
1573806
Grant/Contract Number:  
FC02-04ER54698
Resource Type:
Accepted Manuscript
Journal Name:
Plasma Physics and Controlled Fusion
Additional Journal Information:
Journal Volume: 61; Journal Issue: 12; Journal ID: ISSN 0741-3335
Publisher:
IOP Science
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; tungsten; redeposition; divertor; erosion

Citation Formats

Guterl, J., Wampler, W. R., Rudakov, D., Abrams, T., Wang, H. Q., McLean, A. G., and Snyder, P. Reduced model of high-Z impurity redeposition and erosion in tokamak divertor and its application to DIII-D experiments. United States: N. p., 2019. Web. doi:10.1088/1361-6587/ab5144.
Guterl, J., Wampler, W. R., Rudakov, D., Abrams, T., Wang, H. Q., McLean, A. G., & Snyder, P. Reduced model of high-Z impurity redeposition and erosion in tokamak divertor and its application to DIII-D experiments. United States. doi:10.1088/1361-6587/ab5144.
Guterl, J., Wampler, W. R., Rudakov, D., Abrams, T., Wang, H. Q., McLean, A. G., and Snyder, P. Mon . "Reduced model of high-Z impurity redeposition and erosion in tokamak divertor and its application to DIII-D experiments". United States. doi:10.1088/1361-6587/ab5144.
@article{osti_1573806,
title = {Reduced model of high-Z impurity redeposition and erosion in tokamak divertor and its application to DIII-D experiments},
author = {Guterl, J. and Wampler, W. R. and Rudakov, D. and Abrams, T. and Wang, H. Q. and McLean, A. G. and Snyder, P.},
abstractNote = {A reduced model of high-Z impurities erosion and redeposition is presented to analyze net erosion of tungsten material in divertor attached plasma conditions measured in DIII-D experiments. This reduced model is tailored to quantify the redeposition and the net erosion on high-Z material samples of sufficiently small dimensions to be considered exposed to uniform plasma conditions. For those uniform plasma conditions, the spatial distribution of redeposited high-Z impurities is well approximated by an analytical distribution characterized by a few parameters. The fraction of high-Z impurity eroding and redepositing on a material sample is then obtained by integrating this distribution across the material sample. Here, the ratio of net erosion rates of tungsten measured experimentally from tungsten samples of different sizes exposed to the same attached plasma conditions are well reproduced with this reduced model. It is shown that uncertainties induced by radially non-uniform plasma conditions in experiments can be significantly reduced by exposing samples to high density divertor plasma. Several enhanced experimental setups are proposed to measure and compare net erosion rates from samples of various areas during a single plasma experiment.},
doi = {10.1088/1361-6587/ab5144},
journal = {Plasma Physics and Controlled Fusion},
number = 12,
volume = 61,
place = {United States},
year = {2019},
month = {11}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on November 11, 2020
Publisher's Version of Record

Save / Share:

Works referenced in this record:

II. The energy spectrum of ejected atoms during the high energy sputtering of gold
journal, August 1968


Tungsten as material for plasma-facing components in fusion devices
journal, August 2011


High-Z material erosion and its control in DIII-D carbon divertor
journal, August 2017


Material erosion at the vessel walls of future fusion devices
journal, March 2003


Plasma-surface interaction in the Be/W environment: Conclusions drawn from the JET-ILW for ITER
journal, August 2015


An experimental comparison of gross and net erosion of Mo in the DIII-D divertor
journal, July 2013


Near‐surface sputtered particle transport for an oblique incidence magnetic field plasma
journal, August 1990

  • Brooks, J. N.
  • Physics of Fluids B: Plasma Physics, Vol. 2, Issue 8
  • DOI: 10.1063/1.859457

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


Measurements of net erosion and redeposition of molybdenum in DIII-D
journal, July 2013


Net versus gross erosion of high- Z materials in the divertor of DIII-D
journal, April 2014


Modelling of tungsten re-deposition coefficient
journal, August 2015


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


Tridyn-binary collision simulation of atomic collisions and dynamic composition changes in solids
journal, November 1988


Gross and net erosion of tungsten in the outer strike-point region of ASDEX Upgrade
journal, January 2016


Energy spectra of sputtered species under sub-keV ion bombardment: experiments and computer simulations
journal, April 1999

  • Mousel, T.; Eckstein, W.; Gnaser, H.
  • Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Vol. 152, Issue 1
  • DOI: 10.1016/S0168-583X(98)00976-8

Kinetic Theory Analysis of Sheaths and Shocks
journal, January 1996


Experimental validation of a model for particle recycling and tungsten erosion during ELMs in the DIII-D divertor
journal, December 2018


Erosion of tungsten and carbon markers in the outer divertor of ASDEX-Upgrade
journal, March 2007


Tungsten divertor erosion in all metal devices: Lessons from the ITER like wall of JET
journal, July 2013


A full tungsten divertor for ITER: Physics issues and design status
journal, July 2013


Divertor materials evaluation system (DiMES)
journal, October 1998


Simulation of the plasma-wall interaction in a tokamak with the Monte Carlo code ERO-TEXTOR
journal, May 2000


Analysis of a tungsten sputtering experiment in DIII-D and code/data validation of high redeposition/reduced erosion
journal, May 2015


Assessment of erosion, deposition and fuel retention in the JET-ILW divertor from ion beam analysis data
journal, August 2017


Tungsten erosion in the outer divertor of JET
journal, June 2007


Particle trajectories in a sheath in a strongly tilted magnetic field
journal, March 1998

  • Cohen, R. H.; Ryutov, D. D.
  • Physics of Plasmas, Vol. 5, Issue 3
  • DOI: 10.1063/1.872764

Overview of the recent DiMES and MiMES experiments in DIII-D
journal, December 2009


Monte Carlo simulations of tungsten redeposition at the divertor target
journal, January 2014