Interchange-turbulence-based radial transport model for SOLPS-ITER: A COMPASS case study

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389021%3A_____%2F20%3A00531650" target="_blank" >RIV/61389021:_____/20:00531650 - isvavai.cz</a>

Výsledek na webu

<a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/ctpp.201900155" target="_blank" >https://onlinelibrary.wiley.com/doi/abs/10.1002/ctpp.201900155</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/ctpp.201900155" target="_blank" >10.1002/ctpp.201900155</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Interchange-turbulence-based radial transport model for SOLPS-ITER: A COMPASS case study

Popis výsledku v původním jazyce

Mean-field plasma edge transport codes such as SOLPS-ITER heavily rely on ad-hoc radial diffusion coefficients to approximately model anomalous transport. Such coefficients are experimentally determined and vary between different machines, and also depend on the operational regime and plasma location within the same device. Therefore, to match experimental data the modeller is required to manually tune several free parameters in expensive simulations, and the code's predictive capabilities are significantly downgraded. As a solution, a new model has been developed for SOLPS-ITER, solving an additional transport equation for the turbulent kinetic energy k, derived by consistently time-averaging the Braginskii equations, and including a diffusive closure for the anomalous particle flux. This closure model relates the anomalous diffusion coefficient to the local k value. The resulting equation structure and its closure are inspired by TOKAM2D isothermal interchange turbulence simulation results. Within this model, fewer and hopefully more universal free parameters are retained, thus improving the code's predictive capabilities. The new model has been tested on a COMPASS case for which upstream plasma profiles were available. Experimental data and a reference solution, obtained by matching the profiles through manual tuning of radial diffusivities, have been used to estimate the parameters of our new transport model. A ballooned particle diffusivity profile is retrieved by the new radial transport model, thanks to the proposed interchange drive. The obtained upstream profiles qualitatively agree with the experiment and prove the new model is a promising first attempt to be further refined.

Název v anglickém jazyce

Interchange-turbulence-based radial transport model for SOLPS-ITER: A COMPASS case study

Popis výsledku anglicky

Mean-field plasma edge transport codes such as SOLPS-ITER heavily rely on ad-hoc radial diffusion coefficients to approximately model anomalous transport. Such coefficients are experimentally determined and vary between different machines, and also depend on the operational regime and plasma location within the same device. Therefore, to match experimental data the modeller is required to manually tune several free parameters in expensive simulations, and the code's predictive capabilities are significantly downgraded. As a solution, a new model has been developed for SOLPS-ITER, solving an additional transport equation for the turbulent kinetic energy k, derived by consistently time-averaging the Braginskii equations, and including a diffusive closure for the anomalous particle flux. This closure model relates the anomalous diffusion coefficient to the local k value. The resulting equation structure and its closure are inspired by TOKAM2D isothermal interchange turbulence simulation results. Within this model, fewer and hopefully more universal free parameters are retained, thus improving the code's predictive capabilities. The new model has been tested on a COMPASS case for which upstream plasma profiles were available. Experimental data and a reference solution, obtained by matching the profiles through manual tuning of radial diffusivities, have been used to estimate the parameters of our new transport model. A ballooned particle diffusivity profile is retrieved by the new radial transport model, thanks to the proposed interchange drive. The obtained upstream profiles qualitatively agree with the experiment and prove the new model is a promising first attempt to be further refined.

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

<a href="/cs/project/LM2015045" target="_blank" >LM2015045: COMPASS – Tokamak pro výzkum termonukleární fúze</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Contributions to Plasma Physics

ISSN

0863-1042

e-ISSN

—

Svazek periodika

60

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

9

Strana od-do

e201900155

Kód UT WoS článku

000507000800001

EID výsledku v databázi Scopus

2-s2.0-85077882879