Overview of the JET results in support to ITER

Abstract

The 2014–2016 JET results are reviewed in the light of their significance for optimising the ITER research plan for the active and non-active operation. More than 60 h of plasma operation with ITER first wall materials successfully took place since its installation in 2011. New multi-machine scaling of the type I-ELM divertor energy flux density to ITER is supported by first principle modelling. ITER relevant disruption experiments and first principle modelling are reported with a set of three disruption mitigation valves mimicking the ITER setup. Insights of the L–H power threshold in Deuterium and Hydrogen are given, stressing the importance of the magnetic configurations and the recent measurements of fine-scale structures in the edge radial electric. Dimensionless scans of the core and pedestal confinement provide new information to elucidate the importance of the first wall material on the fusion performance. H-mode plasmas at ITER triangularity (H = 1 at βN ~ 1.8 and n/nGW ~ 0.6) have been sustained at 2 MA during 5 s. The ITER neutronics codes have been validated on high performance experiments. Prospects for the coming D–T campaign and 14 MeV neutron calibration strategy are reviewed.

DiracR-matrix calculations for the electron-impact excitation of neutral tungsten providing noninvasive diagnostics for magnetic confinement fusion

“…In terms of its application, tungsten is the leading material choice for plasma facing components (PFCs) in the divertor region of ITER, with initial experimental investigations underway at JET to assess its suitability [21][22][23]. However, PFCs in the divertor region will unavoidably come into contact with the plasma, resulting in an influx of tungsten impurities from the PFCs into the core plasma.…”

Scientific and technical challenges on the road towards fusion electricity

“…In general the smaller devices are more flexible and can test new ideas more quickly. Those ideas that work are then tested on JET [15] and the results are extrapolated towards ITER. Also ASDEX-Upgrade is equipped with a full metal wall (largely tungsten, and more recently also some areas with Eurofer -the structural material foreseen for DEMO).…”

Study of up–down poloidal density asymmetry of high- impurities with the new impurity version of XGCa

“…Study of the high charge-number (high-Z) impurity particle effect in a tokamak plasma is a high priority research area especially because tungsten has been chosen as the armour material on the divertor plates. Experiments have found that the tungsten impurity particles alter the plasma confinement property significantly Loarte et al 2015;Litaudon & et al 2017).…”