3D modelling of thermal loads during unmitigated vertical displacement events in ITER and JET

F. J. Artola; A. Redl; S. N. Gerasimov; R. A. Pitts; I. S. Carvalho; M. Kong; G. Simic; A. Loarte; J. Van Blarcum; the JOREK team; the JET contributors; the EUROfusion Tokamak Exploitation Team

arXiv · 2604.22516

3D modelling of thermal loads during unmitigated vertical displacement events in ITER and JET

F. J. Artola·A. Redl·S. N. Gerasimov·R. A. Pitts·I. S. Carvalho·M. Kong·G. Simic·A. Loarte·J. Van Blarcum·the JOREK team·the JET contributors·the EUROfusion Tokamak Exploitation Team

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Abstract

Predicting three-dimensional thermal loads during tokamak disruptions is essential for ITER yet remains weakly developed. We present a physics-based workflow that couples MHD simulations of vertical displacement events with field line tracing on a realistic 3D first wall model and a transient wall thermal response. The approach is validated against JET discharges with beryllium main chamber armour, reproducing key global dynamics, non-axisymmetric current features, and the occurrence (or absence) of melting, thereby building confidence in the methodology. We then apply the same workflow to ITER-relevant conditions with tungsten (W) armour, consistent with the new 2024 ITER re-baseline, to assess disruption heat loads and their 3D localization. The resulting analysis demonstrates the resilience of the ITER W first wall against these events and provides predictions for the energy deposition and current flow profiles. Beyond these studies, the workflow enables scenario-by-scenario estimates of disruption-induced thermal loading, allowing to assess the disruption-budget consumption for these events in future devices.

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F. J. Artola, A. Redl, S. N. Gerasimov, R. A. Pitts, I. S. Carvalho, M. Kong, G. Simic, A. Loarte, J. Van Blarcum, the JOREK team, the JET contributors, the EUROfusion Tokamak Exploitation Team. 2026-04-24. 3D modelling of thermal loads during unmitigated vertical displacement events in ITER and JET. https://arxiv.org/abs/2604.22516

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