Details

Autor(en) / Beteiligte

• Insulander Björk, K
• Vallhagen, O
• Papp, G
• Reux, C
• Embreus, O
• Rachlew, E
• Fülöp, T
• Upgrade Team, the ASDEX
• contributors, JET
• MST1 Team, the EUROfusion

Titel

Modelling of runaway electron dynamics during argon-induced disruptions in ASDEX Upgrade and JET

Ist Teil von

• Plasma physics and controlled fusion, 2021-08, Vol.63 (8), p.85021

Ort / Verlag

IOP Publishing

Erscheinungsjahr

2021

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Abstract Disruptions in tokamak plasmas may lead to the generation of runaway electrons that have the potential to damage plasma-facing components. Improved understanding of the runaway generation process requires interpretative modelling of experiments. In this work we simulate eight discharges in the ASDEX Upgrade and JET tokamaks, where argon gas was injected to trigger the disruption. We use a fluid modelling framework with the capability to model the generation of runaway electrons through the hot-tail, Dreicer and avalanche mechanisms, as well as runaway electron losses. Using experimentally based initial values of plasma current and electron temperature and density, we can reproduce the plasma current evolution using realistic assumptions about temperature evolution and assimilation of the injected argon in the plasma. The assumptions and results are similar for the modelled discharges in ASDEX Upgrade and JET. For the modelled discharges in ASDEX Upgrade, where the initial temperature was comparatively high, we had to assume that a large fraction of the hot-tail runaway electrons were lost in order to reproduce the measured current evolution.