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Title: An analytical expression for ion velocities at the wall including the sheath electric field and surface biasing for erosion modeling at JET ILW

Abstract

For simulation of plasma-facing component erosion in fusion experiments, an analytical expression for the ion velocity just before the surface impact including the local electric field and an optional surface biasing effect is suggested. Energy and angular impact distributions and the resulting effective sputtering yields were produced for several experimental scenarios at JET ILW mostly involving PFCs exposed to an oblique magnetic field. The analytic solution has been applied as an improvement to earlier ERO modelling of localized, Be outer limiter, RF-enhanced erosion, modulated by toggling of a remote, however magnetically connected ICRH antenna. The effective W sputtering yields due to D and Be ion impact in Type-I and Type-III ELMs and inter-ELM conditions were also estimated using the analytical approach and benchmarked by spectroscopy. The intra-ELM W sputtering flux increases almost 10 times in comparison to the inter-ELM flux.

Authors:
 [1];  [2];  [2];  [2];  [3];  [3];  [4];  [5];  [5];  [6];  [7];  [7];  [7];  [7];  [7];  [8]
  1. National Research Nuclear Univ. MEPhI, Moscow (Russian Federation); Forschungszentrum Julich (Germany)
  2. Forschungszentrum Julich (Germany)
  3. National Research Nuclear Univ. MEPhI, Moscow (Russian Federation)
  4. Max Planck Inst. of Plasma Physics, Garching (Germany)
  5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  6. Univ. of Lisbon (Portugal); Culham Centre for Fusion Energy (CCFE), Abingdon (United Kingdom)
  7. Culham Centre for Fusion Energy (CCFE), Abingdon (United Kingdom)
  8. Research Centre for Energy, Environment and Technology (CIEMAT), Madrid (Spain)
Publication Date:
Research Org.:
Culham Centre for Fusion Energy (CCFE), Abingdon (United Kingdom); National Research Nuclear Univ. MEPhI, Moscow (Russian Federation); Forschungszentrum Juelich (Germany); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE; European Commission (EC); Ministry of Education and Science of the Russian Federation
OSTI Identifier:
1408615
Grant/Contract Number:
AC05-00OR22725; 633053; 14.Y26.31.0008
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nuclear Materials and Energy
Additional Journal Information:
Journal Volume: 12; Journal ID: ISSN 2352-1791
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; plasma-surface interaction; JET; ITER-like wall; beryllium; erosion; oblique magnetic field; electric field; ELM

Citation Formats

Borodkina, I., Borodin, D., Brezinsek, S., Kirschner, A., Tsvetkov, I. V., Kurnaev, V. A., Bobkov, V., Klepper, C. C., Lasa, A., Guillemaut, C., Jacquet, P., Stamp, M. F., Giroud, C., Silburn, S., Balboa, I., and Solano, E. An analytical expression for ion velocities at the wall including the sheath electric field and surface biasing for erosion modeling at JET ILW. United States: N. p., 2017. Web. doi:10.1016/j.nme.2017.03.031.
Borodkina, I., Borodin, D., Brezinsek, S., Kirschner, A., Tsvetkov, I. V., Kurnaev, V. A., Bobkov, V., Klepper, C. C., Lasa, A., Guillemaut, C., Jacquet, P., Stamp, M. F., Giroud, C., Silburn, S., Balboa, I., & Solano, E. An analytical expression for ion velocities at the wall including the sheath electric field and surface biasing for erosion modeling at JET ILW. United States. doi:10.1016/j.nme.2017.03.031.
Borodkina, I., Borodin, D., Brezinsek, S., Kirschner, A., Tsvetkov, I. V., Kurnaev, V. A., Bobkov, V., Klepper, C. C., Lasa, A., Guillemaut, C., Jacquet, P., Stamp, M. F., Giroud, C., Silburn, S., Balboa, I., and Solano, E. Wed . "An analytical expression for ion velocities at the wall including the sheath electric field and surface biasing for erosion modeling at JET ILW". United States. doi:10.1016/j.nme.2017.03.031. https://www.osti.gov/servlets/purl/1408615.
@article{osti_1408615,
title = {An analytical expression for ion velocities at the wall including the sheath electric field and surface biasing for erosion modeling at JET ILW},
author = {Borodkina, I. and Borodin, D. and Brezinsek, S. and Kirschner, A. and Tsvetkov, I. V. and Kurnaev, V. A. and Bobkov, V. and Klepper, C. C. and Lasa, A. and Guillemaut, C. and Jacquet, P. and Stamp, M. F. and Giroud, C. and Silburn, S. and Balboa, I. and Solano, E.},
abstractNote = {For simulation of plasma-facing component erosion in fusion experiments, an analytical expression for the ion velocity just before the surface impact including the local electric field and an optional surface biasing effect is suggested. Energy and angular impact distributions and the resulting effective sputtering yields were produced for several experimental scenarios at JET ILW mostly involving PFCs exposed to an oblique magnetic field. The analytic solution has been applied as an improvement to earlier ERO modelling of localized, Be outer limiter, RF-enhanced erosion, modulated by toggling of a remote, however magnetically connected ICRH antenna. The effective W sputtering yields due to D and Be ion impact in Type-I and Type-III ELMs and inter-ELM conditions were also estimated using the analytical approach and benchmarked by spectroscopy. The intra-ELM W sputtering flux increases almost 10 times in comparison to the inter-ELM flux.},
doi = {10.1016/j.nme.2017.03.031},
journal = {Nuclear Materials and Energy},
number = ,
volume = 12,
place = {United States},
year = {Wed Apr 12 00:00:00 EDT 2017},
month = {Wed Apr 12 00:00:00 EDT 2017}
}

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