Premium
Integrated Modelling of Nitrogen Seeded JET ILW Discharges for H‐mode and Hybrid Scenarios
Author(s) -
IvanovaStanik I.,
Zagórski R.,
Telesca G.,
Czarnecka A.,
Challis C.,
Hobirk J.
Publication year - 2014
Publication title -
contributions to plasma physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.531
H-Index - 47
eISSN - 1521-3986
pISSN - 0863-1042
DOI - 10.1002/ctpp.201410024
Subject(s) - plasma , tungsten , jet (fluid) , nitrogen , atomic physics , seeding , physics , flux (metallurgy) , materials science , tokamak , mode (computer interface) , ion , computational physics , mechanics , thermodynamics , nuclear physics , quantum mechanics , computer science , metallurgy , operating system
In this paper numerical simulations with COREDIV code of JET discharges with ITER‐like wall are presented. We concentrate on the JET H‐mode and hybrid scenarios with nitrogen seeding and all simulations have been performed with the same transport model and only the discharge input parameters like auxiliary heating P aux , line average plasma density n lin e , confinement factor H 98 , nitrogen input flux Γ puff N were changed in the calcu lations. The separatrix density n sep e is an input parameter in our model and has been kept equal to 0.4÷0.5 n lin e in the simulations, with the recycling coefficient adjusted accordingly. It has been shown that COREDIV is able to reproduce basic parameters of nitrogen seeded discharges for both H‐mode and hybrid scenarios. We have achieved reasonable agreement with global plasma parameters like radiations levels, Z eff and tungsten concentrations and the plasma profiles, including density, temperature and radiation are in very good agreement with experimental data. The agreement of the code results with the experimental data might be even better, if the simulations are further tuned taking into account uncertainties to the sputtering model, separatrix density or SOL transport. Simulations show that the observed Z eff level is defined mostly by the low Z impurity content, Be and N 2 in the considered shots. It has been found that the tungsten radiation plays always very important role and can not be mitigated even by strong influx of nitrogen. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)