Numerical modelling for beam duct heat loads calculations and application to the new 1 MW neutral beam injector in the COMPASS tokamak

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389021%3A_____%2F22%3A00565919" target="_blank" >RIV/61389021:_____/22:00565919 - isvavai.cz</a>

Výsledek na webu

<a href="https://iopscience.iop.org/article/10.1088/1361-6587/ac985e" target="_blank" >https://iopscience.iop.org/article/10.1088/1361-6587/ac985e</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1361-6587/ac985e" target="_blank" >10.1088/1361-6587/ac985e</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Numerical modelling for beam duct heat loads calculations and application to the new 1 MW neutral beam injector in the COMPASS tokamak

Popis výsledku v původním jazyce

We introduce detailed numerical modelling of the fast neutral particles inside the duct of a new neutral beam injector (NBI) recently installed at the COMPASS tokamak (major radius R 0 = 0.56 m , vessel midplane minor radius a = 0.23 m , toroidal field B t = 0.9-2.1 T ). This new NBI system is able to deliver 1 M W power to the plasma at nominal injection energy of 80 k e V . Collisions with the background neutrals inside the beam duct give birth to fast ions according to the density of the gas and tabulated cross-sections. The ion trajectories are then computed in the complete 3D magnetic field, showing the importance of the stray magnetic field and the magnitude of the field within the gap in between toroidal coils.During the experimental campaign dedicated to the new 1 MW NBI, the beam duct heating was measured by a row of thermocouples located on the top-half of the beam duct. The fast ions collisions with the duct wall cause a local temperature increase with a characteristic pattern. In COMPASS, the location of the fast ions power deposition measured experimentally is in qualitative agreement with modelling of ion losses when following them after the re-ionization process. We trace back the details of the orbits corresponding to deposition at the hot-spot inside the beam duct. Quantitative comparison between the experiment and the simulation shows that a larger than expected amount of neutral gas was inside the duct and this study will guide the design of the future NBI duct in COMPASS Upgrade.

Název v anglickém jazyce

Numerical modelling for beam duct heat loads calculations and application to the new 1 MW neutral beam injector in the COMPASS tokamak

Popis výsledku anglicky

We introduce detailed numerical modelling of the fast neutral particles inside the duct of a new neutral beam injector (NBI) recently installed at the COMPASS tokamak (major radius R 0 = 0.56 m , vessel midplane minor radius a = 0.23 m , toroidal field B t = 0.9-2.1 T ). This new NBI system is able to deliver 1 M W power to the plasma at nominal injection energy of 80 k e V . Collisions with the background neutrals inside the beam duct give birth to fast ions according to the density of the gas and tabulated cross-sections. The ion trajectories are then computed in the complete 3D magnetic field, showing the importance of the stray magnetic field and the magnitude of the field within the gap in between toroidal coils.During the experimental campaign dedicated to the new 1 MW NBI, the beam duct heating was measured by a row of thermocouples located on the top-half of the beam duct. The fast ions collisions with the duct wall cause a local temperature increase with a characteristic pattern. In COMPASS, the location of the fast ions power deposition measured experimentally is in qualitative agreement with modelling of ion losses when following them after the re-ionization process. We trace back the details of the orbits corresponding to deposition at the hot-spot inside the beam duct. Quantitative comparison between the experiment and the simulation shows that a larger than expected amount of neutral gas was inside the duct and this study will guide the design of the future NBI duct in COMPASS Upgrade.

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

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

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

64

Číslo periodika v rámci svazku

12

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

13

Strana od-do

125001

Kód UT WoS článku

000868886200001

EID výsledku v databázi Scopus

2-s2.0-85141031959