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arXiv · 1309.4890

Physics of plasma burn-through and DYON simulations for the JET ITER-like wall

Hyun-Tae Kim·A. C. C. Sips·EFDA-JET contributors
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Abstract

This paper presents the DYON simulations of the plasma burn-through phase at Joint European Torus (JET) with the ITER-like wall. The main purpose of the study is to validate the simulations with the ITER-like wall, made of beryllium. Without impurities, the burn-through process of a pure deuterium plasma is described using DYON simulations, and the criterion for deuterium burn-through is derived analytically. The plasma burn-through with impurities are simulated using wall-sputtering models in the DYON code, which are modified for the ITER-like wall. The wall-sputtering models and the validation against JET data are presented. The impact of the assumed plasma parameters in DYON simulations are discussed by means of parameter scans. As a result, the operation space of prefill gas pressure and toroidal electric field for plasma burn-through in JET is compared to the Townsend avalanche criterion.

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Hyun-Tae Kim, A. C. C. Sips, EFDA-JET contributors. 2013-09-19. Physics of plasma burn-through and DYON simulations for the JET ITER-like wall. https://doi.org/10.1088/0029-5515%2F53%2F8%2F083024

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