Modelling the effect of divertor closure on detachment onset in DIII-D with the SOLPS code
Abstract
SOLPS modelling has shown that divertor plasma detachment occurs at a lower upstream separatrix density in the more closed DIII-D upper divertor than the open lower divertor, demonstrating the utility of the divertor closure in widening the range of acceptable densities for adequate heat handling. To achieve reduced heat flux and erosion at the plasma-facing components, future devices will need to operate in at least partially detached divertor conditions . Two-dimensional fluid plasma models coupled to Monte Carlo neutral transport simulations, such as SOLPS, have been widely used to predict the onset of detachment. In modelling the DIII-D discharges, the cross-field transport coefficients are constrained to reproduce the experimental upstream profiles. The closed divertor has been modelled with the same input parameters of the open divertor, allowing a direct comparison of the target conditions in both geometries. SOLPS simulations indicate that a higher molecular density correlates strongly with lower electron temperatures. The increased closure of the upper divertor improves the trapping of neutrals, thereby reducing the power density deposited at the target and facilitating detachment, in agreement with experimental observations.
- Authors:
-
- Oak Ridge Associated Univ., Oak Ridge, TN (United States)
- Dalian Univ. of Technology, Dalian (China). School of Physics
- General Atomics, San Diego, CA (United States)
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Publication Date:
- Research Org.:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Sponsoring Org.:
- USDOE National Nuclear Security Administration (NNSA)
- OSTI Identifier:
- 1491633
- Alternate Identifier(s):
- OSTI ID: 1434964
- Report Number(s):
- LLNL-JRNL-751782
Journal ID: ISSN 0863-1042; 936705
- Grant/Contract Number:
- AC52-07NA27344; FC02‐04ER54698; DE‐FC02‐04ER54698; DE‐AC05‐06OR23100
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Contributions to Plasma Physics
- Additional Journal Information:
- Journal Volume: 58; Journal Issue: 6-8; Journal ID: ISSN 0863-1042
- Publisher:
- Wiley
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; closure; detachment; divertor; SOLPS
Citation Formats
Casali, L., Sang, C., Moser, A. L., Covele, B. M., Guo, H. Y., and Samuell, C. Modelling the effect of divertor closure on detachment onset in DIII-D with the SOLPS code. United States: N. p., 2018.
Web. doi:10.1002/ctpp.201700215.
Casali, L., Sang, C., Moser, A. L., Covele, B. M., Guo, H. Y., & Samuell, C. Modelling the effect of divertor closure on detachment onset in DIII-D with the SOLPS code. United States. https://doi.org/10.1002/ctpp.201700215
Casali, L., Sang, C., Moser, A. L., Covele, B. M., Guo, H. Y., and Samuell, C. Thu .
"Modelling the effect of divertor closure on detachment onset in DIII-D with the SOLPS code". United States. https://doi.org/10.1002/ctpp.201700215. https://www.osti.gov/servlets/purl/1491633.
@article{osti_1491633,
title = {Modelling the effect of divertor closure on detachment onset in DIII-D with the SOLPS code},
author = {Casali, L. and Sang, C. and Moser, A. L. and Covele, B. M. and Guo, H. Y. and Samuell, C.},
abstractNote = {SOLPS modelling has shown that divertor plasma detachment occurs at a lower upstream separatrix density in the more closed DIII-D upper divertor than the open lower divertor, demonstrating the utility of the divertor closure in widening the range of acceptable densities for adequate heat handling. To achieve reduced heat flux and erosion at the plasma-facing components, future devices will need to operate in at least partially detached divertor conditions . Two-dimensional fluid plasma models coupled to Monte Carlo neutral transport simulations, such as SOLPS, have been widely used to predict the onset of detachment. In modelling the DIII-D discharges, the cross-field transport coefficients are constrained to reproduce the experimental upstream profiles. The closed divertor has been modelled with the same input parameters of the open divertor, allowing a direct comparison of the target conditions in both geometries. SOLPS simulations indicate that a higher molecular density correlates strongly with lower electron temperatures. The increased closure of the upper divertor improves the trapping of neutrals, thereby reducing the power density deposited at the target and facilitating detachment, in agreement with experimental observations.},
doi = {10.1002/ctpp.201700215},
journal = {Contributions to Plasma Physics},
number = 6-8,
volume = 58,
place = {United States},
year = {2018},
month = {4}
}
Web of Science
Figures / Tables:

Works referenced in this record:
An analytical formula and important parameters for low-energy ion sputtering
journal, January 1980
- Bohdansky, J.; Roth, J.; Bay, H. L.
- Journal of Applied Physics, Vol. 51, Issue 5
Small angle slot divertor concept for long pulse advanced tokamaks
journal, February 2017
- Guo, H. Y.; Sang, C. F.; Stangeby, P. C.
- Nuclear Fusion, Vol. 57, Issue 4
Obtaining reactor-relevant divertor conditions in tokamaks
journal, April 2011
- Stangeby, P. C.; Leonard, A. W.
- Nuclear Fusion, Vol. 51, Issue 6
Reconstruction of current profile parameters and plasma shapes in tokamaks
journal, November 1985
- Lao, L. L.; St. John, H.; Stambaugh, R. D.
- Nuclear Fusion, Vol. 25, Issue 11
Presentation of the New SOLPS-ITER Code Package for Tokamak Plasma Edge Modelling
journal, January 2016
- Bonnin, Xavier; Dekeyser, Wouter; Pitts, Richard
- Plasma and Fusion Research, Vol. 11, Issue 0
The ASDEX Upgrade divertor IIb—a closed divertor for strongly shaped plasmas
journal, September 2003
- Neu, R.; Fuchs, J. C.; Kallenbach, A.
- Nuclear Fusion, Vol. 43, Issue 10
Radiative divertor and scrape-off layer experiments in open and baffled divertors on DIII-D
journal, November 1999
- Allen, S. L.; Brooks, N. H.; Bastasz, R.
- Nuclear Fusion, Vol. 39, Issue 11Y
Effects of divertor geometry on tokamak plasmas
journal, May 2001
- Loarte, Alberto
- Plasma Physics and Controlled Fusion, Vol. 43, Issue 6
Interpretations of the impact of cross-field drifts on divertor flows in DIII-D with UEDGE
journal, August 2017
- Jaervinen, A. E.; Allen, S. L.; Groth, M.
- Nuclear Materials and Energy, Vol. 12
Impurity seeding for tokamak power exhaust: from present devices via ITER to DEMO
journal, November 2013
- Kallenbach, A.; Bernert, M.; Dux, R.
- Plasma Physics and Controlled Fusion, Vol. 55, Issue 12
The effect of a metal wall on confinement in JET and ASDEX Upgrade
journal, November 2013
- Beurskens, M. N. A.; Schweinzer, J.; Angioni, C.
- Plasma Physics and Controlled Fusion, Vol. 55, Issue 12
Works referencing / citing this record:
First experimental tests of a new small angle slot divertor on DIII-D
journal, July 2019
- Guo, H. Y.; Wang, H. Q.; Watkins, J. G.
- Nuclear Fusion, Vol. 59, Issue 8
Studying divertor relevant plasmas in the Pilot-PSI linear plasma device: experiments versus modelling
journal, November 2018
- Ješko, K.; Marandet, Y.; Bufferand, H.
- Plasma Physics and Controlled Fusion, Vol. 60, Issue 12
DIII-D research towards establishing the scientific basis for future fusion reactors
journal, June 2019
- Petty, C. C.
- Nuclear Fusion, Vol. 59, Issue 11
Figures / Tables found in this record: