Experimental evidence of very short power decay lengths in H-mode discharges in the COMPASS tokamak

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21340%2F24%3A00369877" target="_blank" >RIV/68407700:21340/24:00369877 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61389021:_____/24:00581974

Výsledek na webu

<a href="https://doi.org/10.1088/1361-6587/ad08f0" target="_blank" >https://doi.org/10.1088/1361-6587/ad08f0</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1361-6587/ad08f0" target="_blank" >10.1088/1361-6587/ad08f0</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Experimental evidence of very short power decay lengths in H-mode discharges in the COMPASS tokamak

Popis výsledku v původním jazyce

Analysis of the heat fluxes in the scrape-off layer (SOL) plasma is important for prediction of divertor tile heat loads in future reactor-sized tokamak machines. Typically, the radial heat flux profile can be accurately characterized by the decay length parameter λ q . The predictions are then based on the dependence of λ q on plasma and machine parameters. In the recent years, several empirical scaling models were derived from a collective database of decay lengths observed in several large tokamaks as well as two spherical tokamaks. Most recently, a report from the TCV tokamak showed a deviation from several of the proposed models. In this work, ~ 100 edge plasma profiles of ELMy H-mode discharges were collected from the COMPASS tokamak database for heat flux analysis. The COMPASS tokamak has similar machine size and plasma parameters to the TCV tokamak offering a valuable comparison. The λ q was measured in both the downstream and the upstream SOL utilizing a divertor probe array validated by an IR camera and the Thomson scattering diagnostics. A comparison with the predictions of several scaling models indicated an occurrence of anomalously short (by a factor of 2–5) inter-ELM power decay lengths in both upstream and downstream, as well as a difference in λ q between these two regions. Possible causes related to the accuracy of magnetic reconstruction were eliminated and physics-based sources of apparent compression effects were hypothesized as a motivation for future research.

Název v anglickém jazyce

Experimental evidence of very short power decay lengths in H-mode discharges in the COMPASS tokamak

Popis výsledku anglicky

Analysis of the heat fluxes in the scrape-off layer (SOL) plasma is important for prediction of divertor tile heat loads in future reactor-sized tokamak machines. Typically, the radial heat flux profile can be accurately characterized by the decay length parameter λ q . The predictions are then based on the dependence of λ q on plasma and machine parameters. In the recent years, several empirical scaling models were derived from a collective database of decay lengths observed in several large tokamaks as well as two spherical tokamaks. Most recently, a report from the TCV tokamak showed a deviation from several of the proposed models. In this work, ~ 100 edge plasma profiles of ELMy H-mode discharges were collected from the COMPASS tokamak database for heat flux analysis. The COMPASS tokamak has similar machine size and plasma parameters to the TCV tokamak offering a valuable comparison. The λ q was measured in both the downstream and the upstream SOL utilizing a divertor probe array validated by an IR camera and the Thomson scattering diagnostics. A comparison with the predictions of several scaling models indicated an occurrence of anomalously short (by a factor of 2–5) inter-ELM power decay lengths in both upstream and downstream, as well as a difference in λ q between these two regions. Possible causes related to the accuracy of magnetic reconstruction were eliminated and physics-based sources of apparent compression effects were hypothesized as a motivation for future research.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2024

Kód důvěrnosti údajů

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

Název periodika

Plasma Physics and Controlled Fusion

ISSN

0741-3335

e-ISSN

1361-6587

Svazek periodika

66

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

10

Strana od-do

—

Kód UT WoS článku

001121381400001

EID výsledku v databázi Scopus

2-s2.0-85181871318