Advances in understanding of high- Z material erosion and re-deposition in low-Z wall environment in DIII-D

Ding, R.; Rudakov, D. L.; Stangeby, P. C.; Wampler, W. R.; Abrams, T.; Brezinsek, S.; Briesemeister, A.; Bykov, I.; Chan, V. S.; Chrobak, C. P.; Elder, J. D.; Guo, H. Y.; Guterl, J.; Kirschner, A.; Lasnier, C. J.; Leonard, A. W.; Makowski, M. A.; McLean, A. G.; Snyder, P. B.; Thomas, D. M.; Tskhakaya, D.; Unterberg, E. A.; Wang, H. Q.; Watkins, J. G.

doi:10.1088/1741-4326/aa6451

Title: Advances in understanding of high- Z material erosion and re-deposition in low-Z wall environment in DIII-D

Journal Article · 24 March 2017 · Nuclear Fusion

DOI: https://doi.org/10.1088/1741-4326/aa6451 · OSTI ID:1491638

Ding, R. ^[1]; Rudakov, D. L. ^[2]; Stangeby, P. C. ^[3]; Wampler, W. R. ^[4]; Abrams, T. ^[5]; Brezinsek, S. ^[6]; Briesemeister, A. ^[7]; Bykov, I. ^[2]; Chan, V. S. ^[5]; Chrobak, C. P. ^[5]; Elder, J. D. ^[3]; Guo, H. Y. ^[5]; Guterl, J. ^[8]; Kirschner, A. ^[6]; Lasnier, C. J. ^[9]; Leonard, A. W. ^[5]; Makowski, M. A. ^[9]; McLean, A. G. ^[9]; Snyder, P. B. ^[5]; Thomas, D. M. ^[5] more »

Oak Ridge Associated Univ., Oak Ridge, TN (United States); Chinese Academy of Sciences (CAS), Beijing (China). Inst. of Plasma Physics; General Atomics, San Diego, CA (United States)
Univ. of California, San Diego, CA (United States)
Univ. of Toronto, ON (Canada). Inst. for Aerospace Studies
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
General Atomics, San Diego, CA (United States)
Julich Research Centre (Germany). Inst. of Energy and Climate Research- Plasma Physics
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Oak Ridge Associated Univ., Oak Ridge, TN (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Univ. of Vienna (Austria). Fusion @OAW. Inst. of Applied Physics

Dedicated DIII-D experiments coupled with modeling reveal that the net erosion rate of high-Z materials, i.e. Mo and W, is strongly affected by carbon concentration in the plasma and the magnetic pre-sheath properties. We have investigated different methods such as electrical biasing and local gas injection to control high-Z material erosion. The net erosion rate of high-Z materials is significantly reduced due to the high local re-deposition ratio. The ERO modeling shows that the local re-deposition ratio is mainly controlled by the electric field and plasma density within the magnetic pre-sheath. The net erosion can be significantly suppressed by reducing the sheath potential drop. A high carbon impurity concentration in the background plasma is also found to reduce the net erosion rate of high-Z materials. Both DIII-D experiments and modeling show that local ¹³CH₄ injection can create a carbon coating on the metal surface. The profile of ¹³C deposition provides quantitative information on radial transport due to E × B drift and the cross-field diffusion. The deuterium gas injection upstream of the W sample can reduce W net erosion rate by plasma perturbation. The inter-ELM W erosion we measured in H-mode plasmas, rates at different radial locations are well reproduced by ERO modeling taking into account charge-state-resolved carbon ion flux in the background plasma calculated using the OEDGE code.

View Accepted Manuscript (DOE)

Cite

Export

Save

Research Organization:: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); General Atomics, San Diego, CA (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

Sponsoring Organization:: USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Grant/Contract Number:: AC52-07NA27344; AC04-94AL85000; GA-DE-SC0008698; AC05-06OR23100; FG02-07ER54917; AC05-00OR22725; FC02-04ER54698

OSTI ID:: 1491638

Alternate ID(s):: OSTI ID: 1357016; OSTI ID: 1374606; OSTI ID: 1374610; OSTI ID: 1503985

Report Number(s):: LLNL-JRNL-736452; SAND-2017-0016J; 836266

Journal Information:: Nuclear Fusion, Vol. 57, Issue 5; ISSN 0029-5515

Publisher:: IOP ScienceCopyright Statement

Country of Publication:: United States

Language:: English

Citation Metrics:

Cited by: 20 works

Citation information provided by
Web of Science

References (24)

A full tungsten divertor for ITER: Physics issues and design status Pitts, R. A.; Carpentier, S.; Escourbiac, F. Journal of Nuclear Materials, Vol. 438 https://doi.org/10.1016/j.jnucmat.2013.01.008	journal	July 2013
Plasma-surface interaction in the Be/W environment: Conclusions drawn from the JET-ILW for ITER Brezinsek, S. Journal of Nuclear Materials, Vol. 463 https://doi.org/10.1016/j.jnucmat.2014.12.007	journal	August 2015
ELM-resolved divertor erosion in the JET ITER-Like Wall Den Harder, N.; Brezinsek, S.; Pütterich, T. Nuclear Fusion, Vol. 56, Issue 2 https://doi.org/10.1088/0029-5515/56/2/026014	journal	January 2016
Plasma-wall interaction and plasma behaviour in the non-boronised all tungsten ASDEX Upgrade Dux, R.; Bobkov, V.; Herrmann, A. Journal of Nuclear Materials, Vol. 390-391 https://doi.org/10.1016/j.jnucmat.2009.01.225	journal	June 2009
Monte Carlo simulations of tungsten redeposition at the divertor target Chankin, A. V.; Coster, D. P.; Dux, R. Plasma Physics and Controlled Fusion, Vol. 56, Issue 2 https://doi.org/10.1088/0741-3335/56/2/025003	journal	January 2014
Modelling of tungsten re-deposition coefficient Tskhakaya, D.; Groth, M. Journal of Nuclear Materials, Vol. 463 https://doi.org/10.1016/j.jnucmat.2014.10.086	journal	August 2015
An experimental comparison of gross and net erosion of Mo in the DIII-D divertor Stangeby, P. C.; Rudakov, D. L.; Wampler, W. R. Journal of Nuclear Materials, Vol. 438 https://doi.org/10.1016/j.jnucmat.2013.01.052	journal	July 2013
Divertor materials evaluation system (DiMES) Wong, C. P. C.; Whyte, D. G.; Bastasz, R. J. Journal of Nuclear Materials, Vol. 258-263 https://doi.org/10.1016/S0022-3115(98)00407-3	journal	October 1998
Tungsten divertor erosion in all metal devices: Lessons from the ITER like wall of JET van Rooij, G. J.; Coenen, J. W.; Aho-Mantila, L. Journal of Nuclear Materials, Vol. 438 https://doi.org/10.1016/j.jnucmat.2013.01.007	journal	July 2013
Quantification of tungsten sputtering at W/C twin limiters in TEXTOR with the aid of local WF ₆ injection Brezinsek, S.; Borodin, D.; Coenen, J. W. Physica Scripta, Vol. T145 https://doi.org/10.1088/0031-8949/2011/T145/014016	journal	December 2011
Measurements of net erosion and redeposition of molybdenum in DIII-D Wampler, W. R.; Stangeby, P. C.; Watkins, J. G. Journal of Nuclear Materials, Vol. 438 https://doi.org/10.1016/j.jnucmat.2013.01.178	journal	July 2013
Net versus gross erosion of high- Z materials in the divertor of DIII-D Rudakov, D. L.; Stangeby, P. C.; Wampler, W. R. Physica Scripta, Vol. T159 https://doi.org/10.1088/0031-8949/2014/T159/014030	journal	April 2014
Simulation of gross and net erosion of high- Z materials in the DIII-D divertor Ding, R.; Stangeby, P. C.; Rudakov, D. L. Nuclear Fusion, Vol. 56, Issue 1 https://doi.org/10.1088/0029-5515/56/1/016021	journal	December 2015
Advanced simulation of mixed-material erosion/evolution and application to low and high-Z containing plasma facing components Brooks, J. N.; Hassanein, A.; Sizyuk, T. Journal of Nuclear Materials, Vol. 438 https://doi.org/10.1016/j.jnucmat.2013.01.142	journal	July 2013
Simulation of the plasma-wall interaction in a tokamak with the Monte Carlo code ERO-TEXTOR Kirschner, A.; Philipps, V.; Winter, J. Nuclear Fusion, Vol. 40, Issue 5 https://doi.org/10.1088/0029-5515/40/5/311	journal	May 2000
Interpretive modeling of simple-as-possible-plasma discharges on DIII-D using the OEDGE code Stangeby, P. C.; Elder, J. D.; Boedo, J. A. Journal of Nuclear Materials, Vol. 313-316 https://doi.org/10.1016/S0022-3115(02)01470-8	journal	March 2003
Estimations of erosion fluxes, material deposition and tritium retention in the divertor of ITER Kirschner, A.; Borodin, D.; Philipps, V. Journal of Nuclear Materials, Vol. 390-391 https://doi.org/10.1016/j.jnucmat.2009.01.155	journal	June 2009
Plasma–wall transition in an oblique magnetic field Chodura, R. Physics of Fluids, Vol. 25, Issue 9 https://doi.org/10.1063/1.863955	journal	January 1982
Near‐surface sputtered particle transport for an oblique incidence magnetic field plasma Brooks, J. N. Physics of Fluids B: Plasma Physics, Vol. 2, Issue 8 https://doi.org/10.1063/1.859457	journal	August 1990
The Chodura sheath for angles of a few degrees between the magnetic field and the surface of divertor targets and limiters Stangeby, P. C. Nuclear Fusion, Vol. 52, Issue 8 https://doi.org/10.1088/0029-5515/52/8/083012	journal	July 2012
Control of high-Z PFC erosion by local gas injection in DIII-D Rudakov, D. L.; Stangeby, P. C.; Wong, C. P. C. Journal of Nuclear Materials, Vol. 463 https://doi.org/10.1016/j.jnucmat.2014.10.056	journal	August 2015
Simulation of light emission from hydrocarbon injection in TEXTOR using the ERO code Ding, R.; Kirschner, A.; Borodin, D. Plasma Physics and Controlled Fusion, Vol. 51, Issue 5 https://doi.org/10.1088/0741-3335/51/5/055019	journal	April 2009
Deposition and re-erosion studies by means of local impurity injection in TEXTOR Kirschner, A.; Kreter, A.; Wienhold, P. Journal of Nuclear Materials, Vol. 415, Issue 1 https://doi.org/10.1016/j.jnucmat.2010.10.058	journal	August 2011
Localized tungsten deposition in divertor region in JT-60U Ueda, Y.; Fukumoto, M.; Watanabe, J. Nuclear Fusion, Vol. 49, Issue 6 https://doi.org/10.1088/0029-5515/49/6/065027	journal	May 2009

Cited By (1)

Plasma cleaning of ITER edge Thomson scattering mock-up mirror in the EAST tokamak Yan, Rong; Moser, Lucas; Wang, Baoguo Nuclear Fusion, Vol. 58, Issue 2 https://doi.org/10.1088/1741-4326/aa96b8	journal	December 2017