Energy confinement in ohmic discharges in H, D and T on JET-ILW
ORAL
Abstract
The energy confinement of ohmic discharges is investigated in JET-ILW using discharges with steady density plateaus and neutral beam blips to obtain accurate profiles of the intrinsic rotation and ion temperature using main ion charge exchange spectroscopy. A comparison between matched hydrogen and deuterium pulses has experimentally demonstrated a shift from electron to ion dominated transport at the LOC-SOC transition and a reduction in energy confinement with reduced isotope mass. The latter is largely due to an increase in electron-ion equipartition power at lower isotope mass, but when accounting for the difference in heat flux at matched density we still find a higher effective ion heat diffusivity at lower isotope mass.
This contribution is expanding on earlier preliminary results [1] with more deuterium data and further interpretation using a gyro-fluid model (TGLF). We aim to present our dataset including matched tritium pulses by the time of the conference.
[1] E. Delabie et al., proceeding of the 44th EPS conference, Belfast, UK (2017)
This contribution is expanding on earlier preliminary results [1] with more deuterium data and further interpretation using a gyro-fluid model (TGLF). We aim to present our dataset including matched tritium pulses by the time of the conference.
[1] E. Delabie et al., proceeding of the 44th EPS conference, Belfast, UK (2017)
*Work supported, in part, by US DOE under Contract No. DE-AC05-00OR22725 with UT-Battelle, LLC. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 and 2019-2020 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission.
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Presenters
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Ephrem Delabie
- Oak Ridge National Lab
- Oak Ridge National Laboratory, Oak Ridge, USA