Magnetic turnstiles in nonresonant stellarator divertor

Punjabi, Alkesh; Boozer, Allen H.

doi:10.1063/5.0068913

Title: Magnetic turnstiles in nonresonant stellarator divertor

Abstract

Nonresonant stellarator divertors have magnetic flux tubes, called magnetic turnstiles, that cross cantori, which are fractal remnants of destroyed invariant tori with holes, that lie outside the outermost confining surface. The exiting and entering flux tubes can be adjacent as is generally expected but can also have the unexpected feature of entering or exiting at separate locations of the cantori. Not only can there be two types of turnstiles but pseudo-turnstiles can also exist. A pseudo-turnstile is formed when a cantorus has a sufficiently large, although limited, radial excursion to strike a surrounding chamber wall. The existence of non-adjacent and adjacent turnstiles and pseudo-turnstiles resolves issues that arose in earlier simulations of nonresonant stellarator divertors [A. Punjabi and A. H. Boozer, Phys. Plasmas 27, 012503 (2020)].

Authors:

^[1];

^[2]

Hampton Univ., Hampton, VA (United States)
Columbia Univ., New York, NY (United States)

Publication Date:: Sat Jan 01 00:00:00 EST 2022

Research Org.:: Hampton Univ., Hampton, VA (United States); Columbia Univ., New York, NY (United States); Hampton Univ., VA (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES)

Contributing Org.:: National Energy Research Scientific Computing Center (NERSC)

OSTI Identifier:: 1864856

Alternate Identifier(s):: OSTI ID: 1903116

Grant/Contract Number:: SC0020107; FG02-03ER54696

Resource Type:: Accepted Manuscript

Journal Name:: Physics of Plasmas

Additional Journal Information:: Journal Volume: 29; Journal Issue: 1; Journal ID: ISSN 1070-664X

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Stellarator; divertor; nonresonant divertor; magnetic turnstiles; stellarators, divertors, nonresonant, magnetic turnstiles

Citation Formats


                    Punjabi, Alkesh, and Boozer, Allen H. Magnetic turnstiles in nonresonant stellarator divertor.  United States: N. p., 2022. 
Web.  doi:10.1063/5.0068913.

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                    Punjabi, Alkesh, & Boozer, Allen H. Magnetic turnstiles in nonresonant stellarator divertor.  United States.  https://doi.org/10.1063/5.0068913

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                    Punjabi, Alkesh, and Boozer, Allen H. Sat .  
"Magnetic turnstiles in nonresonant stellarator divertor".  United States.  https://doi.org/10.1063/5.0068913.  https://www.osti.gov/servlets/purl/1864856.

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@article{osti_1864856,

  title        = {Magnetic turnstiles in nonresonant stellarator divertor},

  author       = {Punjabi, Alkesh and Boozer, Allen H.},

  abstractNote = {Nonresonant stellarator divertors have magnetic flux tubes, called magnetic turnstiles, that cross cantori, which are fractal remnants of destroyed invariant tori with holes, that lie outside the outermost confining surface. The exiting and entering flux tubes can be adjacent as is generally expected but can also have the unexpected feature of entering or exiting at separate locations of the cantori. Not only can there be two types of turnstiles but pseudo-turnstiles can also exist. A pseudo-turnstile is formed when a cantorus has a sufficiently large, although limited, radial excursion to strike a surrounding chamber wall. The existence of non-adjacent and adjacent turnstiles and pseudo-turnstiles resolves issues that arose in earlier simulations of nonresonant stellarator divertors [A. Punjabi and A. H. Boozer, Phys. Plasmas 27, 012503 (2020)].},

  doi          = {10.1063/5.0068913},

  journal      = {Physics of Plasmas},

  number       = 1,

  volume       = 29,

  place        = {United States},

  year         = {Sat Jan 01 00:00:00 EST 2022},

  month        = {Sat Jan 01 00:00:00 EST 2022}

}

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Works referenced in this record:

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journal, March 2017

Bader, A.; Boozer, A. H.; Hegna, C. C.
Physics of Plasmas, Vol. 24, Issue 3
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Boozer, Allen H.; Punjabi, Alkesh
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journal, September 2015

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Title: Magnetic turnstiles in nonresonant stellarator divertor

Abstract

Citation Formats

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