dc.creator | Wynn, A. | es |
dc.creator | Lipschultz, B. | es |
dc.creator | Cziegler, I. | es |
dc.creator | Harrison, J. | es |
dc.creator | Jaervinen, A. | es |
dc.creator | Jet Contributors | es |
dc.creator | García Muñoz, Manuel | es |
dc.date.accessioned | 2020-07-17T14:06:30Z | |
dc.date.available | 2020-07-17T14:06:30Z | |
dc.date.issued | 2018 | |
dc.identifier.citation | Wynn, A., Lipschultz, B., Cziegler, I., Harrison, J., Jaervinen, A., Jet Contributors, y García Muñoz, M. (2018). Investigation into the formation of the scrape-off layer density shoulder in JET ITER-like wall L-mode and H-mode plasmas. Nuclear Fusion, 58 (5), 1-22. | |
dc.identifier.issn | 1741-4326 | es |
dc.identifier.uri | https://hdl.handle.net/11441/99621 | |
dc.description.abstract | The low temperature boundary layer plasma (scrape-off layer or SOL) between the hot core
and the surrounding vessel determines the level of power loading, erosion and implantation
of material surfaces, and thus the viability of tokamak-based fusion as an energy source. This
study explores mechanisms affecting the formation of flattened density profiles, so-called
‘density shoulders’, in the low-field side (LFS) SOL, which modify ion and neutral fluxes
to surfaces—and subsequent erosion. There is evidence against local enhancement of
ionization inducing shoulder formation. We find that increases in SOL parallel resistivity, Λdiv
(=[L||νeiΩi]/csΩe), postulated to lead to shoulder growth through changes in SOL turbulence
characteristics, correlates with increases in SOL shoulder amplitude, As, but only under a
subset of conditions (D2-fuelled L-mode density scans with outer strike point on the horizontal
target). Λdiv fails to correlate with As for cases of N2 seeding or during sweeping of the strike
point across the horizontal target. The limited correlation of Λdiv and As is also found for
H-mode discharges. Thus, while it may be necessary for Λdiv to be above a threshold of ~1
for shoulder formation and/or growth, another mechanism is required. More significantly, we
find that in contrast to parallel resistivity, outer divertor recycling, as quantified by the total
outer divertor Balmer Dα emission, I–Dα, does scale with As where Λdiv does and even where
Λdiv does not. Divertor recycling could lead to SOL density shoulder formation through: (a)
reducing the parallel to the field flow (loss) of ions out of the SOL to the divertor; and (b)
changes in radial electric fields which lead to E × B poloidal flows as well as potentially affecting SOL turbulence birth characteristics. Thus, changes in divertor recycling may be
the sole process involved in bringing | es |
dc.description.sponsorship | EURATOM 633053 | es |
dc.description.sponsorship | EPSRC EP/L01663X/1 | es |
dc.description.sponsorship | EPSRC EP/K504178/1 | es |
dc.description.sponsorship | RCUK Energy EP/I501045 | es |
dc.format | application/pdf | es |
dc.format.extent | 22 p. | es |
dc.language.iso | eng | es |
dc.publisher | IOP Publishing | es |
dc.relation.ispartof | Nuclear Fusion, 58 (5), 1-22. | |
dc.rights | Attribution-NonCommercial-NoDerivatives 4.0 Internacional | * |
dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/4.0/ | * |
dc.subject | Tokamaks | es |
dc.subject | Scrapeoff layer transport | es |
dc.subject | Divertor recycling | es |
dc.subject | Divertor geometry | es |
dc.subject | SOL shoulder | es |
dc.title | Investigation into the formation of the scrape-off layer density shoulder in JET ITER-like wall L-mode and H-mode plasmas | es |
dc.type | info:eu-repo/semantics/article | es |
dcterms.identifier | https://ror.org/03yxnpp24 | |
dc.type.version | info:eu-repo/semantics/publishedVersion | es |
dc.rights.accessRights | info:eu-repo/semantics/openAccess | es |
dc.contributor.affiliation | Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear | es |
dc.relation.projectID | 633053 | es |
dc.relation.projectID | EP/L01663X/1 | es |
dc.relation.projectID | EP/K504178/1 | es |
dc.relation.projectID | EP/I501045 | es |
dc.relation.publisherversion | https://doi.org/10.1088/1741-4326/aaad78 | es |
dc.identifier.doi | 10.1088/1741-4326/aaad78 | es |
dc.contributor.group | Universidad de Sevilla. RNM138: Física Nuclear Aplicada | es |
dc.journaltitle | Nuclear Fusion | es |
dc.publication.volumen | 58 | es |
dc.publication.issue | 5 | es |
dc.publication.initialPage | 1 | es |
dc.publication.endPage | 22 | es |