EPS 2019

P2.1024 Predictive modelling of the Be main chamber erosion in the JET-ILW

9 Jul 2019, 14:00

2h

Building U6 (University of Milano-Bicocca UNIMIB)

MCF Poster P2

Speaker

D.V. Borodin (EPS 2019)

Description

See full abstract here
http://ocs.ciemat.es/EPS2019ABS/pdf/P2.1024.pdf

JET is a unique tokamak equipped with the ITER-like wall (ILW) comprised of beryllium (Be) main chamber and tungsten (W) divertor. JET allows operation with tritium (T), thus studying the H/D/T isotope effect on the plasma-wall interaction (PWI). Be limiters meet the most of the direct plasma impact, however part of the liner and support structures made of nickel(Ni)-containing Inconel are exposed to the charge exchange (CX) ion flux. CX erosion is also dominates in the shadowed areas of the Be plasma-facing components (PFC). Be impurity typically causes the most of the W sputtering excluding intra-ELM: in the ohmic and the L-mode divertor plasmas and even in the H-mode inter-ELM. The radiation cooling issue due to the high-Z W (and Ni) impurities is critical for the plasma confinement and stability of the main scenarios foreseen for the upcoming JET DT campaign.
The 3D Monte-Carlo PWI and impurity transport ERO2.0 code [J.Romazanov et al., PSI-2018, invited, NME 18 (2019) 331­338] is an established tool, which was applied to erosion studies at JET with the extrapolation to ITER [D.Borodin et al., IAEA FEC-2018]. In the present work the previous simulations for the D plasma JET experiment are used as a starting point for the parameter studies aimed in the detailed study the variation range of the Be main chamber erosion with a focus on the a) isotope effect on physical sputtering (predictive); b) the role of the CX ion erosion, which is of particular importance in diverted magnetic configurations. In addition, the contribution of the chemical assisted physical sputtering (CAPS) is simulated using the refined reaction data and model in the ERO2.0.
In the previous studies [1] the passive Be spectroscopy in a single midplane sightline was used for the model and data validation. In the present work it is complemented with additional sightlines and comparison with the Z-effective measurements.
See the author list of "Overview of the JET preparation for Deuterium-Tritium Operation" by E.Joffrin et al. to be published in Nuclear Fusion Special issue: 27th Fusion Energy Conference (Ahmedabad, India, 2018)