Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgrade

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389021%3A_____%2F17%3A00481519" target="_blank" >RIV/61389021:_____/17:00481519 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.nme.2017.03.018" target="_blank" >http://dx.doi.org/10.1016/j.nme.2017.03.018</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.nme.2017.03.018" target="_blank" >10.1016/j.nme.2017.03.018</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgrade

Popis výsledku v původním jazyce

A heat pulse experiment was carried out in the tokamak ASDEX Upgrade to estimate the stochastic layer width of a deuterium L-mode discharge with externally applied Magnetic Perturbations. The method relies on the deposition of ECRH pulses in the plasma edge while measuring the divertor target heat flux with high temporal resolution IR thermography and Langmuir probes. The experimental results were compared to simulations of the time dependent heat pulse propagation on a constant plasma background with the EMC3-EIRENE code package, using an ad-hoc screening model. If no screening was taken into account in the simulations a decrease in the characteristic heat pulse propagation time was observed, which shows that the heat transport is enhanced compared to the screened cases. No such enhancement was found in the experiment, indicating strong screening. In further simulations the effect of screening on the target fluxes was investigated for varying densities. For low densities it was found that screening reduces the strike line splitting strongly, while for higher densities no strong strike line splitting was found, independent of the screening degree. For strongly detached L-mode conditions with MPs experi- ments at AUG indicate that the lobe structures vanish completely.

Název v anglickém jazyce

Determination of the stochastic layer properties induced by magnetic perturbations via heat pulse experiments at ASDEX upgrade

Popis výsledku anglicky

A heat pulse experiment was carried out in the tokamak ASDEX Upgrade to estimate the stochastic layer width of a deuterium L-mode discharge with externally applied Magnetic Perturbations. The method relies on the deposition of ECRH pulses in the plasma edge while measuring the divertor target heat flux with high temporal resolution IR thermography and Langmuir probes. The experimental results were compared to simulations of the time dependent heat pulse propagation on a constant plasma background with the EMC3-EIRENE code package, using an ad-hoc screening model. If no screening was taken into account in the simulations a decrease in the characteristic heat pulse propagation time was observed, which shows that the heat transport is enhanced compared to the screened cases. No such enhancement was found in the experiment, indicating strong screening. In further simulations the effect of screening on the target fluxes was investigated for varying densities. For low densities it was found that screening reduces the strike line splitting strongly, while for higher densities no strong strike line splitting was found, independent of the screening degree. For strongly detached L-mode conditions with MPs experi- ments at AUG indicate that the lobe structures vanish completely.

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

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

Nuclear Materials and Energy

ISSN

2352-1791

e-ISSN

—

Svazek periodika

12

Číslo periodika v rámci svazku

August

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

7

Strana od-do

831-837

Kód UT WoS článku

000417293300135

EID výsledku v databázi Scopus

2-s2.0-85013434703