Speaker
Description
We present the modelling of detachment burn-through scenarios with a new exhaust model developed in ReMKiT1D [1], a framework for 1D fluid-kinetic modelling and collisional-radiative interactions, and the 2D fluid modelling suite SOLPS-ITER. Starting from a "1D" SOLPS case, a detached plasma background representing the MAST-Upgrade Super-X divertor is reproduced within the ReMKiT1D exhaust model, in both a fluid "benchmark" case and kinetic electron case. The latter introduces non-Maxwellian dynamics not captured in SOLPS that can enhance fast electron transport during energetic transient events and modify interactions with the detachment gas cloud [2, 3, 4]. Detachment burn-through is then modelled by applying heat pulses of different energies to the background, comparing the two cases from the ReMKiT1D exhaust model with SOLPS. Complementary interpretations of detachment burn-through from both codes will improve our basic understanding - such as the apparent lack of detachment front pressure balance in 2D SOLPS not seen in 1D fluid codes [5] - and to improve the accuracy and predictive capabilities of the exhaust model in ReMKiT1D.
Preliminary simulations have shown that the required transient energy to burn through the detachment front has a high sensitivity to the timescale of wall recycling. In addition, the neutral pressure downstream of the front is highly sensitive to the energetic efficiency with which neutrals reflect from the walls.
This work has been funded by the EPSRC Energy Programme [grant number EP/W006839/1].
References
[1] Mijin et al. Comp. Phys. Comm. 300 (2024)
[2] Power et al. Nucl. Fusion 63 086013 (2023)
[3] Tskhakaya et al. Contrib. Plasma Phys. 48(1-3), 89-93 (2008)
[4] Chankin et al. Plasma Phys. Control. Fusion 60 (2018)
[5] Dudson et al. Plasma Phys. Control. Fusion 61(6) (2019)