Power exhaust by core radiation at COMPASS tokamak

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389021%3A_____%2F21%3A00542717" target="_blank" >RIV/61389021:_____/21:00542717 - isvavai.cz</a>

Alternative codes found

RIV/00216208:11320/21:10432147

Result on the web

<a href="https://iopscience.iop.org/article/10.1088/1741-4326/abd3ea" target="_blank" >https://iopscience.iop.org/article/10.1088/1741-4326/abd3ea</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1741-4326/abd3ea" target="_blank" >10.1088/1741-4326/abd3ea</a>

Result language

angličtina

Original language name

Power exhaust by core radiation at COMPASS tokamak

Original language description

Substantial power dissipation in the edge plasma is required for the safe operation of ITER and next-step fusion reactors, otherwise unmitigated heat fluxes at the divertor plasma-facing components (PFCs) would easily exceed their material limits. Traditionally, such heat flux mitigation is linked to the regime of detachment, which is characterised by a significant pressure gradient between upstream and downstream scrape-off layer (SOL). However, the physics phenomena responsible for power dissipation and pressure loss are distinctly different, especially when the power dissipation is achieved by impurity seeding. In principle, it is possible to achieve substantial mitigation of the heat fluxes while maintaining conservation of the pressure along the open field lines in the SOL. This regime can be accessed by injection of medium-or high-Z impurities, which mostly radiate inside the last closed flux surface. The critical question related to such an approach is the effect on confinement and perspective fusion power generation in future thermonuclear reactors. In this work, we report on experiments at COMPASS tokamak, where neon and argon impurities were injected in ohmic or NBI-heated low confinement plasmas. With appropriate seeding waveform, stable scenarios were achieved, avoiding the radiative collapse of plasmas. Significant reduction of heat fluxes at the outer target was observed, with heat flux pattern similar to the one previously achieved by nitrogen seeding. The reduction of downstream pressure was, however, accompanied by an equal reduction of upstream pressure, indicating that the power dissipation occurred inside the separatrix. Indeed, the impurity cooling is causing a significant drop of edge temperature, however, the effect in the plasma centre is much less pronounced.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10305 - Fluids and plasma physics (including surface physics)

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2021

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Nuclear Fusion

ISSN

0029-5515

e-ISSN

1741-4326

Volume of the periodical

61

Issue of the periodical within the volume

3

Country of publishing house

AT - AUSTRIA

Number of pages

11

Pages from-to

036016

UT code for WoS article

000617157000001

EID of the result in the Scopus database

2-s2.0-85101461070