Study of passively stable, fully detached divertor plasma regimes attained in innovative long-legged divertor configurations
Abstract
Numerical modeling of divertor configurations with radially or vertically extended, tightly baffled, outer divertor legs has demonstrated the existence of a passively-stable fully detached divertor regime. Here in the simulations, long-legged divertors provide up to an order-of-magnitude increase in peak power handling capability compared to conventional divertors. The key physics for attaining the passively stable, fully detached regime in these simulations involves the interplay of strong convective plasma transport to the divertor leg outer sidewall, confinement of neutral gas in the divertor volume, geometric effects including a secondary X-point, and atomic radiation. New analysis shows that in this regime the detachment front location is set by the balance between the power entering the divertor leg and the losses to the walls of the divertor channel. Correspondingly, the maximum power that can be accommodated by the divertor, while still staying detached, increases with the poloidal length of the leg. The detached regime access window in terms of input power, density and impurity seeding concentration varies quantitatively depending on divertor geometry and modeling assumptions most specifically, cross-field transport to the side walls.
- Authors:
-
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
- Univ. of York (United Kingdom)
- Publication Date:
- Research Org.:
- Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
- Sponsoring Org.:
- USDOE National Nuclear Security Administration (NNSA)
- OSTI Identifier:
- 1884626
- Report Number(s):
- LLNL-JRNL-767297
Journal ID: ISSN 0029-5515; 957724; TRN: US2308100
- Grant/Contract Number:
- AC52-07NA27344
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Nuclear Fusion
- Additional Journal Information:
- Journal Volume: 60; Journal Issue: 1; Journal ID: ISSN 0029-5515
- Publisher:
- IOP Science
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; tokamak; divertor; ADX
Citation Formats
Umansky, M. V., LaBombard, B., Brunner, Daniel, Golfinopoulos, T., Kuang, A. Q., Rensink, M. E., Terry, James L., Wigram, Michael, and Whyte, D. G. Study of passively stable, fully detached divertor plasma regimes attained in innovative long-legged divertor configurations. United States: N. p., 2019.
Web. doi:10.1088/1741-4326/ab46f4.
Umansky, M. V., LaBombard, B., Brunner, Daniel, Golfinopoulos, T., Kuang, A. Q., Rensink, M. E., Terry, James L., Wigram, Michael, & Whyte, D. G. Study of passively stable, fully detached divertor plasma regimes attained in innovative long-legged divertor configurations. United States. https://doi.org/10.1088/1741-4326/ab46f4
Umansky, M. V., LaBombard, B., Brunner, Daniel, Golfinopoulos, T., Kuang, A. Q., Rensink, M. E., Terry, James L., Wigram, Michael, and Whyte, D. G. Wed .
"Study of passively stable, fully detached divertor plasma regimes attained in innovative long-legged divertor configurations". United States. https://doi.org/10.1088/1741-4326/ab46f4. https://www.osti.gov/servlets/purl/1884626.
@article{osti_1884626,
title = {Study of passively stable, fully detached divertor plasma regimes attained in innovative long-legged divertor configurations},
author = {Umansky, M. V. and LaBombard, B. and Brunner, Daniel and Golfinopoulos, T. and Kuang, A. Q. and Rensink, M. E. and Terry, James L. and Wigram, Michael and Whyte, D. G.},
abstractNote = {Numerical modeling of divertor configurations with radially or vertically extended, tightly baffled, outer divertor legs has demonstrated the existence of a passively-stable fully detached divertor regime. Here in the simulations, long-legged divertors provide up to an order-of-magnitude increase in peak power handling capability compared to conventional divertors. The key physics for attaining the passively stable, fully detached regime in these simulations involves the interplay of strong convective plasma transport to the divertor leg outer sidewall, confinement of neutral gas in the divertor volume, geometric effects including a secondary X-point, and atomic radiation. New analysis shows that in this regime the detachment front location is set by the balance between the power entering the divertor leg and the losses to the walls of the divertor channel. Correspondingly, the maximum power that can be accommodated by the divertor, while still staying detached, increases with the poloidal length of the leg. The detached regime access window in terms of input power, density and impurity seeding concentration varies quantitatively depending on divertor geometry and modeling assumptions most specifically, cross-field transport to the side walls.},
doi = {10.1088/1741-4326/ab46f4},
journal = {Nuclear Fusion},
number = 1,
volume = 60,
place = {United States},
year = {Wed Oct 30 00:00:00 EDT 2019},
month = {Wed Oct 30 00:00:00 EDT 2019}
}
Works referenced in this record:
Geometrical properties of a “snowflake” divertor
journal, June 2007
- Ryutov, D. D.
- Physics of Plasmas, Vol. 14, Issue 6
On heat loading, novel divertors, and fusion reactors
journal, July 2007
- Kotschenreuther, M.; Valanju, P. M.; Mahajan, S. M.
- Physics of Plasmas, Vol. 14, Issue 7
Physics Basis of a Fusion Development Facility Utilizing the Tokamak Approach
journal, January 2010
- Chan, V. S.; Stambaugh, R. D.; Garofalo, A. M.
- Fusion Science and Technology, Vol. 57, Issue 1
Assessment of X-point target divertor configuration for power handling and detachment front control
journal, August 2017
- Umansky, M. V.; Rensink, M. E.; Rognlien, T. D.
- Nuclear Materials and Energy, Vol. 12
Results from recent detachment experiments in alternative divertor configurations on TCV
journal, March 2017
- Theiler, C.; Lipschultz, B.; Harrison, J.
- Nuclear Fusion, Vol. 57, Issue 7
Surface heat flux feedback controlled impurity seeding experiments with Alcator C-Mod’s high- Z vertical target plate divertor: performance, limitations and implications for fusion power reactors
journal, July 2017
- Brunner, D.; Wolfe, S. M.; LaBombard, B.
- Nuclear Fusion, Vol. 57, Issue 8
Plasma detachment in divertor tokamaks
journal, February 2018
- Leonard, A. W.
- Plasma Physics and Controlled Fusion, Vol. 60, Issue 4
Divertor leg filaments in NSTX-U
journal, October 2018
- Scotti, Filippo; Zweben, Stewart; Soukhanovskii, Vlad
- Nuclear Fusion, Vol. 58, Issue 12
On scrape off layer plasma transport
journal, May 2001
- Krasheninnikov, S. I.
- Physics Letters A, Vol. 283, Issue 5-6
Scaling of the tokamak near the scrape-off layer H-mode power width and implications for ITER
journal, August 2013
- Eich, T.; Leonard, A. W.; Pitts, R. A.
- Nuclear Fusion, Vol. 53, Issue 9
ADX: a high field, high power density, advanced divertor and RF tokamak
journal, April 2015
- LaBombard, B.; Marmar, E.; Irby, J.
- Nuclear Fusion, Vol. 55, Issue 5
Sensitivity of detachment extent to magnetic configuration and external parameters
journal, April 2016
- Lipschultz, Bruce; Parra, Felix I.; Hutchinson, Ian H.
- Nuclear Fusion, Vol. 56, Issue 5
Experimental divertor physics
journal, June 1997
- Pitcher, C. S.; Stangeby, P. C.
- Plasma Physics and Controlled Fusion, Vol. 39, Issue 6
Comments on particle and energy balance in the edge plasma of Alcator C-Mod
journal, September 1998
- Umansky, M. V.; Krasheninnikov, S. I.; LaBombard, B.
- Physics of Plasmas, Vol. 5, Issue 9
Super-X divertors and high power density fusion devices
journal, May 2009
- Valanju, P. M.; Kotschenreuther, M.; Mahajan, S. M.
- Physics of Plasmas, Vol. 16, Issue 5
The Plasma Boundary of Magnetic Fusion Devices
book, January 2000
- Stangeby, Peter C.
- Plasma Physics and Controlled Fusion, Vol. 43, Issue 2
Modeling of particle and energy transport in the edge plasma of Alcator C-Mod
journal, July 1999
- Umansky, M. V.; Krasheninnikov, S. I.; LaBombard, B.
- Physics of Plasmas, Vol. 6, Issue 7
Filamentary transport in the private flux region in MAST
journal, August 2015
- Harrison, J. R.; Fishpool, G. M.; Dudson, B. D.
- Journal of Nuclear Materials, Vol. 463
Numerical Studies of Impurities in Fusion Plasmas
journal, March 1983
- Hulse, Russell A.
- Nuclear Technology - Fusion, Vol. 3, Issue 2
Engineering Assessment of a National High-power Advanced Torus Experiment (NHTX)
conference, June 2007
- Neumeyer, C.; Gentile, C.; Ramakrishnan, S.
- 2007 IEEE 22nd Symposium on Fusion Engineering
A fully implicit, time dependent 2-D fluid code for modeling tokamak edge plasmas
journal, December 1992
- Rognlien, T. D.; Milovich, J. L.; Rensink, M. E.
- Journal of Nuclear Materials, Vol. 196-198
The ARIES Advanced and Conservative Tokamak Power Plant Study
journal, January 2015
- Kessel, C. E.; Tillack, M. S.; Najmabadi, F.
- Fusion Science and Technology, Vol. 67, Issue 1
Attainment of a stable, fully detached plasma state in innovative divertor configurations
journal, May 2017
- Umansky, M. V.; LaBombard, B.; Brunner, D.
- Physics of Plasmas, Vol. 24, Issue 5
Guidance of Divertor Channel by Cusp-Like Magnetic Field for Tokamak Devices
journal, March 2001
- Takase, Haruhiko
- Journal of the Physical Society of Japan, Vol. 70, Issue 3
Convective transport by intermittent blob-filaments: Comparison of theory and experiment
journal, June 2011
- D’Ippolito, D. A.; Myra, J. R.; Zweben, S. J.
- Physics of Plasmas, Vol. 18, Issue 6
Study of a spherical tokamak based volumetric neutron source
journal, January 1998
- Cheng, E. T.; Peng, Y. K. Martin; Cerbone, Ralph
- Fusion Engineering and Design, Vol. 38, Issue 3
Plasma Edge Physics with B2-Eirene
journal, February 2006
- Schneider, R.; Bonnin, X.; Borrass, K.
- Contributions to Plasma Physics, Vol. 46, Issue 1-2