Increased heat dissipation with the X-divertor geometry facilitating detachment onset at lower density in DIII-D

Covele, Brent; Kotschenreuther, M.; Mahajan, S.; Valanju, P.; Leonard, Anthony W.; Watkins, Jonathan G.; Makowski, Michael A.; Fenstermacher, Max E.; Si, H.

doi:10.1088/1741-4326/aa7644

Title: Increased heat dissipation with the X-divertor geometry facilitating detachment onset at lower density in DIII-D

Journal Article · Fri Jun 23 00:00:00 EDT 2017 · Nuclear Fusion

DOI:https://doi.org/10.1088/1741-4326/aa7644· OSTI ID:1390611

Covele, Brent ^[1]; Kotschenreuther, M. ^[2]; Mahajan, S. ^[2]; Valanju, P. ^[2]; Leonard, Anthony W. ^[1]; Watkins, Jonathan G. ^[3]; Makowski, Michael A. ^[4]; Fenstermacher, Max E. ^[4]; Si, H. ^[5]

General Atomics, San Diego, CA (United States)
Univ. of Texas, Austin, TX (United States)
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Chinese Academy of Sciences (CAS), Beijing (China). Inst. of Plasma Physics

The X-Divertor geometry on DIII-D has demonstrated reduced particle and heat fluxes to the target, facilitating detachment onset at ~20% lower upstream density and higher H-mode pedestal pressure than a standard divertor. SOLPS modeling suggests that this effect cannot be explained by an increase in total connection length alone, but rather by the addition of connection length specifically in the power-dissipating volume near the target, via poloidal flux expansion and flaring. But, poloidal flaring must work synergistically with divertor closure to most effectively reduce the detachment density threshold. Furthermore, the model also points to carbon radiation as the primary driver of power dissipation in divertors on the DIII-D floor, which is consistent with experimental observations. Sustainable divertor detachment at lower density has beneficial consequences for energy confinement and current drive efficiency in the core for advanced tokamak (AT) operation, while simultaneously satisfying the exhaust requirements of the plasma-facing components.

View Accepted Manuscript (DOE)

Cite

Export

Save

Research Organization:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Organization:: USDOE Office of Nuclear Energy (NE); USDOE National Nuclear Security Administration (NNSA); National Natural Science Foundation of China (NSFC)

Grant/Contract Number:: AC52-07NA27344; FC02-04ER54698; FG02-04ER54754; FG03-96ER54366; AC04-94AL85000; AC05-00OR22725; 11505234; 11347113

OSTI ID:: 1390611

Alternate ID(s):: OSTI ID: 1871403

Report Number(s):: LLNL-JRNL-834528

Journal Information:: Nuclear Fusion, Vol. 57, Issue 8; ISSN 0029-5515

Publisher:: IOP ScienceCopyright Statement

Country of Publication:: United States

Language:: English

Citation Metrics:

Cited by: 17 works

Citation information provided by
Web of Science

References (14)

Geometrical properties of a “snowflake” divertor Ryutov, D. D. Physics of Plasmas, Vol. 14, Issue 6 https://doi.org/10.1063/1.2738399	journal	June 2007
Plasma detachment in JET Mark I divertor experiments Loarte, A.; Monk, R. D.; Martín-Solís, J. R. Nuclear Fusion, Vol. 38, Issue 3 https://doi.org/10.1088/0029-5515/38/3/303	journal	March 1998
Sensitivity of detachment extent to magnetic configuration and external parameters Lipschultz, Bruce; Parra, Felix I.; Hutchinson, Ian H. Nuclear Fusion, Vol. 56, Issue 5 https://doi.org/10.1088/0029-5515/56/5/056007	journal	April 2016
An exploration of advanced X-divertor scenarios on ITER Covele, B.; Valanju, P.; Kotschenreuther, M. Nuclear Fusion, Vol. 54, Issue 7 https://doi.org/10.1088/0029-5515/54/7/072006	journal	May 2014
Divertor plasma detachment Krasheninnikov, S. I.; Kukushkin, A. S.; Pshenov, A. A. Physics of Plasmas, Vol. 23, Issue 5 https://doi.org/10.1063/1.4948273	journal	May 2016
Magnetic geometry and physics of advanced divertors: The X-divertor and the snowflake Kotschenreuther, Mike; Valanju, Prashant; Covele, Brent Physics of Plasmas, Vol. 20, Issue 10 https://doi.org/10.1063/1.4824735	journal	October 2013
SOLPS modelling of ASDEX upgrade H-mode plasma Chankin, A. V.; Coster, D. P.; Dux, R. Plasma Physics and Controlled Fusion, Vol. 48, Issue 6 https://doi.org/10.1088/0741-3335/48/6/010	journal	May 2006
Super-X divertors and high power density fusion devices Valanju, P. M.; Kotschenreuther, M.; Mahajan, S. M. Physics of Plasmas, Vol. 16, Issue 5 https://doi.org/10.1063/1.3110984	journal	May 2009
ADAS: Atomic data, modelling and analysis for fusion Summers, H. P.; O’Mullane, M. G.; Whiteford, A. D. ATOMIC AND MOLECULAR DATA AND THEIR APPLICATIONS: 5th International Conference on Atomic and Molecular Data and Their Applications (ICAMDATA), AIP Conference Proceedings https://doi.org/10.1063/1.2727374	conference	January 2007
Identifying the location of the OMP separatrix in DIII-D using power accounting Stangeby, P. C.; Canik, J. M.; Elder, J. D. Nuclear Fusion, Vol. 55, Issue 9 https://doi.org/10.1088/0029-5515/55/9/093014	journal	August 2015
A new look at density limits in tokamaks Greenwald, M.; Terry, J. L.; Wolfe, S. M. Nuclear Fusion, Vol. 28, Issue 12 https://doi.org/10.1088/0029-5515/28/12/009	journal	December 1988
Modeling of detachment experiments at DIII-D Canik, J. M.; Briesemeister, A. R.; Lasnier, C. J. Journal of Nuclear Materials, Vol. 463 https://doi.org/10.1016/j.jnucmat.2014.11.077	journal	August 2015
New B2SOLPS5.2 transport code for H-mode regimes in tokamaks Rozhansky, V.; Kaveeva, E.; Molchanov, P. Nuclear Fusion, Vol. 49, Issue 2 https://doi.org/10.1088/0029-5515/49/2/025007	journal	January 2009
Plasma Edge Physics with B2-Eirene Schneider, R.; Bonnin, X.; Borrass, K. Contributions to Plasma Physics, Vol. 46, Issue 1-2 https://doi.org/10.1002/ctpp.200610001	journal	February 2006

Cited By (3)

Progress toward divertor detachment on TCV within H-mode operating parameters Harrison, J. R.; Theiler, C.; Février, O. Plasma Physics and Controlled Fusion, Vol. 61, Issue 6 https://doi.org/10.1088/1361-6587/ab140e	journal	May 2019
Modeling of combined effects of divertor closure and advanced magnetic configuration on detachment in DIII-D by SOLPS Si, H.; Guo, H. Y.; Covele, B. Nuclear Fusion, Vol. 58, Issue 5 https://doi.org/10.1088/1741-4326/aab6c8	journal	April 2018
Plasma detachment in divertor tokamaks Leonard, A. W. Plasma Physics and Controlled Fusion, Vol. 60, Issue 4 https://doi.org/10.1088/1361-6587/aaa7a9	journal	February 2018

Similar Records

Modelling the effect of divertor closure on detachment onset in DIII-D with the SOLPS code

Journal Article · Thu Apr 26 00:00:00 EDT 2018 · Contributions to Plasma Physics · OSTI ID:1390611

Casali, L.; Sang, C.; Moser, A. L.; +3 more

SOLPS modeling of the effect on plasma detachment of closing the lower divertor in DIII-D

Journal Article · Thu Dec 15 00:00:00 EST 2016 · Plasma Physics and Controlled Fusion · OSTI ID:1390611

Sang, C. F.; Stangeby, P. C.; Guo, H. Y.; +5 more

Neutral leakage, power dissipation and pedestal fueling in open vs closed divertors

Journal Article · Fri Jun 05 00:00:00 EDT 2020 · Nuclear Fusion · OSTI ID:1390611

Casali, L.; Eldon, D.; Boedo, J. A.; +2 more

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Title: Increased heat dissipation with the X-divertor geometry facilitating detachment onset at lower density in DIII-D

Citation Formats

References (14)

Cited By (3)

Similar Records

Related Subjects