Exploration of non-resonant divertor features on the Compact Toroidal Hybrid

Garcia, K. A.; Bader, A.; Frerichs, H.; Hartwell, G. J.; Schmitt, J. C.; Allen, N.; Schmitz, O.

doi:10.1088/1741-4326/ad0160

Exploration of non-resonant divertor features on the Compact Toroidal Hybrid

Journal Article · Wed Oct 25 00:00:00 EDT 2023 · Nuclear Fusion

DOI:https://doi.org/10.1088/1741-4326/ad0160· OSTI ID:2203576

; ; ; ; ; Allen, N.;

Abstract

Non-resonant divertors (NRDs) separate the confined plasma from the surrounding plasma facing components (PFCs). The resulting striking field line intersection pattern on these PFCs is insensitive to plasma equilibrium effects. However, a complex scrape-off layer (SOL), created by chaotic magnetic topology in the plasma edge, connects the core plasma to the PFCs through varying magnetic flux tubes. The Compact Toroidal Hybrid (CTH) serves as a test-bed to study this by scanning across its inductive current. Simulations observe a significant change of the chaotic edge structure and an effective distance between the confined plasma and the instrumented wall targets. The intersection pattern is observed to be a narrow helical band, which we claim is a resilient strike line pattern. However, signatures of finger-like structures, defined as heteroclinic tangles in chaotic domains, within the plasma edge connect the island chains to this resilient pattern. The dominant connection length field lines intersecting the targets are observed via heat flux modeling with EMC3-EIRENE. At low inductive current levels, the excursion of the field lines resembles a limited plasma wall scenario. At high currents, a private flux region is created in the area where the helical strike line pattern splits into two bands. These bands are divertor legs with distinct SOL parallel particle flow channels. The results demonstrate the NRD strike line pattern resiliency within CTH, but also show the underlying chaotic edge structure determining if the configuration is diverted or limited. This work supports future design efforts for a mechanical structure for the NRD.

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Sponsoring Organization:: USDOE

Grant/Contract Number:: FG02-00ER54610

OSTI ID:: 2203576

Alternate ID(s):: OSTI ID: 2578809

Journal Information:: Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 12 Vol. 63; ISSN 0029-5515

Publisher:: IOP PublishingCopyright Statement

Country of Publication:: IAEA

Language:: English

References (47)

3D Edge Modeling and Island Divertor Physics Feng, Y.; Sardei, F.; Kisslinger, J. Contributions to Plasma Physics, Vol. 44, Issue 13 https://doi.org/10.1002/ctpp.200410009	journal	April 2004
Initial Vacuum Magnetic Field Mapping in the Compact Toroidal Hybrid Peterson, J. T.; Hartwell, G. J.; Knowlton, S. F. Journal of Fusion Energy, Vol. 26, Issue 1-2 https://doi.org/10.1007/s10894-006-9053-2	journal	December 2006
MOMCON: A spectral code for obtaining three-dimensional magnetohydrodynamic equilibria Hirshman, S. P.; Lee, D. K. Computer Physics Communications, Vol. 39, Issue 2 https://doi.org/10.1016/0010-4655(86)90127-X	journal	February 1986
Transport in Hamiltonian systems Mackay, R. S.; Meiss, J. D.; Percival, I. C. Physica D: Nonlinear Phenomena, Vol. 13, Issue 1-2 https://doi.org/10.1016/0167-2789(84)90270-7	journal	August 1984
Quasi-helically symmetric toroidal stellarators Nührenberg, J.; Zille, R. Physics Letters A, Vol. 129, Issue 2 https://doi.org/10.1016/0375-9601(88)90080-1	journal	May 1988
Stellarator design Boozer, Allen H. Journal of Plasma Physics, Vol. 81, Issue 6 https://doi.org/10.1017/S0022377815001373	journal	December 2015
Impacts of resonant magnetic perturbations on edge carbon transport and emission on EAST with EMC3-EIRENE modelling Dai, S. Y.; Zhang, H. M.; Lyu, B. Journal of Plasma Physics, Vol. 86, Issue 3 https://doi.org/10.1017/S0022377820000422	journal	May 2020
Fractal structure of the magnetic field in the laminar zone of the Dynamic Ergodic Divertor of the Torus Experiment for Technology-Oriented Research (TEXTOR-94) Abdullaev, S. S.; Eich, Th.; Finken, K. H. Physics of Plasmas, Vol. 8, Issue 6 https://doi.org/10.1063/1.1371954	journal	June 2001
Traces of stable and unstable manifolds in heat flux patterns Wingen, A.; Jakubowski, M.; Spatschek, K. H. Physics of Plasmas, Vol. 14, Issue 4 https://doi.org/10.1063/1.2715548	journal	April 2007
Impact of screening of resonant magnetic perturbations in three dimensional edge plasma transport simulations for DIII-D Frerichs, H.; Reiter, D.; Schmitz, O. Physics of Plasmas, Vol. 19, Issue 5 https://doi.org/10.1063/1.4714616	journal	May 2012
Thirty years of turnstiles and transport Meiss, J. D. Chaos: An Interdisciplinary Journal of Nonlinear Science, Vol. 25, Issue 9 https://doi.org/10.1063/1.4915831	journal	September 2015
HSX as an example of a resilient non-resonant divertor Bader, A.; Boozer, A. H.; Hegna, C. C. Physics of Plasmas, Vol. 24, Issue 3 https://doi.org/10.1063/1.4978494	journal	March 2017
Determination of current and rotational transform profiles in a current-carrying stellarator using soft x-ray emissivity measurements Ma, X.; Cianciosa, M. R.; Ennis, D. A. Physics of Plasmas, Vol. 25, Issue 1 https://doi.org/10.1063/1.5013347	journal	January 2018
Simulation of stellarator divertors Boozer, Allen H.; Punjabi, Alkesh Physics of Plasmas, Vol. 25, Issue 9 https://doi.org/10.1063/1.5042666	journal	September 2018
Performance of Wendelstein 7-X stellarator plasmas during the first divertor operation phase Wolf, R. C.; Alonso, A.; Äkäslompolo, S. Physics of Plasmas, Vol. 26, Issue 8 https://doi.org/10.1063/1.5098761	journal	August 2019
Simulation of non-resonant stellarator divertor Punjabi, Alkesh; Boozer, Allen H. Physics of Plasmas, Vol. 27, Issue 1 https://doi.org/10.1063/1.5113907	journal	January 2020
Asymptotical and mapping methods in study of ergodic divertor magnetic field in a toroidal system Abdullaev, S. S.; Finken, K. H.; Spatschek, K. H. Physics of Plasmas, Vol. 6, Issue 1 https://doi.org/10.1063/1.873270	journal	January 1999
A new set of analytical formulae for the computation of the bootstrap current and the neoclassical conductivity in tokamaks Redl, A.; Angioni, C.; Belli, E. Physics of Plasmas, Vol. 28, Issue 2 https://doi.org/10.1063/5.0012664	journal	February 2021
Volumetric recombination in EMC3-EIRENE: Implementation and first application to the pre-fusion power operation phase in ITER Frerichs, H.; Feng, Y.; Bonnin, X. Physics of Plasmas, Vol. 28, Issue 10 https://doi.org/10.1063/5.0062248	journal	October 2021
Magnetic turnstiles in nonresonant stellarator divertor Punjabi, Alkesh; Boozer, Allen H. Physics of Plasmas, Vol. 29, Issue 1 https://doi.org/10.1063/5.0068913	journal	January 2022
Optimization of quasi-symmetric stellarators with self-consistent bootstrap current and energetic particle confinement Landreman, M.; Buller, S.; Drevlak, M. Physics of Plasmas, Vol. 29, Issue 8 https://doi.org/10.1063/5.0098166	journal	August 2022
Design, Construction, and Operation of the Compact Toroidal Hybrid Hartwell, G. J.; Knowlton, S. F.; Hanson, J. D. Fusion Science and Technology, Vol. 72, Issue 1 https://doi.org/10.1080/15361055.2017.1291046	journal	May 2017
Magnetic field line diversion in Helias stellarator configurations: perspectives for divertor operation Strumberger, E. Nuclear Fusion, Vol. 32, Issue 5 https://doi.org/10.1088/0029-5515/32/5/I02	journal	May 1992
Interaction of stochastic boundary layer with plasma facing components Nguyen, F.; Chendrih, P.; Grosman, A. Nuclear Fusion, Vol. 37, Issue 6 https://doi.org/10.1088/0029-5515/37/6/I03	journal	June 1997
Two dimensional modelling approach to transport properties of the TEXTOR-DED laminar zone Eich, T.; Reiser, D.; Finken, K. H. Nuclear Fusion, Vol. 40, Issue 10 https://doi.org/10.1088/0029-5515/40/10/307	journal	October 2000
Modelling of the magnetic field structures and first measurements of heat fluxes for TEXTOR-DED operation Jakubowski, M. W.; Abdullaev, S. S.; Finken, K. H. Nuclear Fusion, Vol. 44, Issue 6 https://doi.org/10.1088/0029-5515/44/6/S01	journal	May 2004
On mapping models of field lines in a stochastic magnetic field Abdullaev, S. S. Nuclear Fusion, Vol. 44, Issue 6 https://doi.org/10.1088/0029-5515/44/6/S02	journal	May 2004
Identification and analysis of transport domains in the stochastic boundary of TEXTOR-DED for different mode spectra Schmitz, O.; Jakubowski, M. W.; Frerichs, H. Nuclear Fusion, Vol. 48, Issue 2 https://doi.org/10.1088/0029-5515/48/2/024009	journal	January 2008
Three-dimensional modeling of plasma edge transport and divertor fluxes during application of resonant magnetic perturbations on ITER Schmitz, O.; Becoulet, M.; Cahyna, P. Nuclear Fusion, Vol. 56, Issue 6 https://doi.org/10.1088/0029-5515/56/6/066008	journal	May 2016
Theoretical and experimental investigations of stochastic boundaries in tokamaks Ghendrih, Ph; Grosman, A.; Capes, H. Plasma Physics and Controlled Fusion, Vol. 38, Issue 10 https://doi.org/10.1088/0741-3335/38/10/002	journal	October 1996
First island divertor experiments on the W7-AS stellarator Grigull, P.; McCormick, K.; Baldzuhn, J. Plasma Physics and Controlled Fusion, Vol. 43, Issue 12A https://doi.org/10.1088/0741-3335/43/12A/313	journal	November 2001
Divertor concept for the W7-X stellarator and mode of operation Renner, H.; Boscary, J.; Greuner, H. Plasma Physics and Controlled Fusion, Vol. 44, Issue 6 https://doi.org/10.1088/0741-3335/44/6/325	journal	May 2002
Aspects of three dimensional transport for ELM control experiments in ITER-similar shape plasmas at low collisionality in DIII-D Schmitz, O.; Evans, T. E.; Fenstermacher, M. E. Plasma Physics and Controlled Fusion, Vol. 50, Issue 12 https://doi.org/10.1088/0741-3335/50/12/124029	journal	November 2008
Stellarator and tokamak plasmas: a comparison Helander, P.; Beidler, C. D.; Bird, T. M. Plasma Physics and Controlled Fusion, Vol. 54, Issue 12 https://doi.org/10.1088/0741-3335/54/12/124009	journal	November 2012
Three-dimensional scrape off layer transport in the helically symmetric experiment HSX Akerson, A. R.; Bader, A.; Hegna, C. C. Plasma Physics and Controlled Fusion, Vol. 58, Issue 8 https://doi.org/10.1088/0741-3335/58/8/084002	journal	June 2016
Minimum magnetic curvature for resilient divertors using Compact Toroidal Hybrid geometry Bader, A.; Hegna, C. C.; Cianciosa, M. Plasma Physics and Controlled Fusion, Vol. 60, Issue 5 https://doi.org/10.1088/1361-6587/aab1ea	journal	March 2018
Three-dimensional impurity transport modeling of neon-seeded and nitrogen-seeded LHD plasmas Kawamura, G.; Tanaka, H.; Mukai, K. Plasma Physics and Controlled Fusion, Vol. 60, Issue 8 https://doi.org/10.1088/1361-6587/aac9ea	journal	June 2018
EMC3-EIRENE simulation of first wall recycling fluxes in W7-X with relation to H-alpha measurements Winters, V. R.; Reimold, F.; König, R. Plasma Physics and Controlled Fusion, Vol. 63, Issue 4 https://doi.org/10.1088/1361-6587/abe39c	journal	March 2021
Review of magnetic islands from the divertor perspective and a simplified heat transport model for the island divertor Feng, Y. Plasma Physics and Controlled Fusion, Vol. 64, Issue 12 https://doi.org/10.1088/1361-6587/ac9ed9	journal	November 2022
Understanding detachment of the W7-X island divertor Feng, Y.; Jakubowski, M.; König, R. Nuclear Fusion, Vol. 61, Issue 8 https://doi.org/10.1088/1741-4326/ac0772	journal	June 2021
Comparison of the influence of 2D and 3D geometry of the main chamber on plasma parameters in the SOL of ASDEX Upgrade Bock, L.; Brida, D.; Faitsch, M. Nuclear Fusion, Vol. 62, Issue 2 https://doi.org/10.1088/1741-4326/ac3f49	journal	December 2021
Experimental signatures of homoclinic tangles in poloidally diverted tokamaks Evans, T. E.; Roeder, R. K. W.; Carter, J. A. Journal of Physics: Conference Series, Vol. 7 https://doi.org/10.1088/1742-6596/7/1/015	journal	January 2005
Resonant Pedestal Pressure Reduction Induced by a Thermal Transport Enhancement due to Stochastic Magnetic Boundary Layers in High Temperature Plasmas Schmitz, O.; Evans, T. E.; Fenstermacher, M. E. Physical Review Letters, Vol. 103, Issue 16 https://doi.org/10.1103/PhysRevLett.103.165005	journal	October 2009
Change of the Magnetic-Field Topology by an Ergodic Divertor and the Effect on the Plasma Structure and Transport Jakubowski, M. W.; Schmitz, O.; Abdullaev, S. S. Physical Review Letters, Vol. 96, Issue 3 https://doi.org/10.1103/PhysRevLett.96.035004	journal	January 2006
Design and Analysis of Divertor Scraper Elements for the W7-X Stellarator Lore, Jeremy D.; Andreeva, Tamara; Boscary, Jean IEEE Transactions on Plasma Science, Vol. 42, Issue 3 https://doi.org/10.1109/TPS.2014.2303649	journal	March 2014
The EIRENE and B2-EIRENE Codes Reiter, D.; Baelmans, M.; Börner, P. Fusion Science and Technology, Vol. 47, Issue 2 https://doi.org/10.13182/FST47-172	journal	February 2005
First Application of 3D Peripheral Plasma Transport Code EMC3-EIRENE to Heliotron J Matoike, Ryota; Kawamura, Gakushi; Ohshima, Shinsuke Plasma and Fusion Research, Vol. 14, Issue 0 https://doi.org/10.1585/pfr.14.3403127	journal	September 2019

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