Speaker
Michael Kovari
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P2.1013.pdf
A one-dimensional scrape-off layer model in the reactor systems code
‘PROCESS’
M. Kovari1, A. Kallenbach2, M. Siccinio2,3
1
CCFE, Culham Science Centre, Abingdon, Oxfordshire, OX14 3DB, UK
2
Max-Planck Institute for Plasma Physics, Garching, Germany
3
EUROfusion Consortium, Garching, Germany
* Tel.: +44 (0)1235-46-6427. E-mail address: michael.kovari@ccfe.ac.uk
We have implemented a one-dimensional scrape-off layer (SOL) model in the PROCESS
fusion reactor systems code. It allows reactor scenarios to be obtained while limiting both
the plasma temperature of the SOL at the entrance to the sheath at the divertor target, and the
power density on the target. The following physical processes are included: convected heat
flux; thermal conduction; momentum conservation; radiation by deuterium, tritium and
impurities; charge exchange; electron impact ionisation; and surface recombination. The
isotropic emission of fast neutrals due to charge exchange from the part of the SOL adjacent
to the target dominates the total power density on the target when the plasma temperature is
reduced below 5 eV.
As the seeded impurity concentration is increased a discontinuous transition is observed
between an attached state where the plasma temperature at the target is high, and an
approximately detached state in which the temperature at the target hits the lower bound of
the simulation.
The inclusion of a simple divertor model restricts the PROCESS optimisation to a more
realistic subset of parameter space.
300
250
200 Plasma temperature at
eV
outer midplane [eV]
150
100
50 Plasma temperature near
target [eV]
0
0 0.0005 0.001 0.0015 0.002
Argon number density fraction
