Speaker
Lorenzo Frassinetti
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P4.1027.pdf
The EUROfusion JET-ILW pedestal database
L. Frassinetti1, S. Saarelma2, F. Imbeaux3, P. Bilkova4, P. Bohm4, R. Fridström1,
E. Giovannozzi5, M. Owsiak6, M. Dunne7, B. Labit8, R. Scannell2, J.C. Hillesheim2 and JET
contributors9*
1
Division of Fusion Plasma Physics, KTH Royal Institute of Technology, Stockholm SE
2
CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB, UK
3
CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France
4
Institute of Plasma Physics of the CAS, Za Slovankou 3, 182 00 Prague 8, Czech Republic
5
ENEA, Fusion and Nuclear Safety Department, Via E. Fermi 45, 00044 Frascati, Italy
6
Poznan Supercomputing and Networking Center, IChB PAS, Noskowskiego 12/14, Poznan, Poland
7
Max-Planck-Institut für Plasmaphysik, Garching, Germany
8
Swiss Plasma Center (SPC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne,Switzerland
9
EUROfusion Consortium, JET, Culham Science Centre, Abingdon, OX14 3DB, UK
* see X. Litaudon et al., Nuclear Fusion 57, 102001 (2017)
To enhance the scientific output of multi-machine comparisons, EUROfusion has promoted
the creation of several databases with common definitions and with a common platform. This
work is an overview of the EUROfusion pedestal database of JET-ILW.
The definitions of the pedestal quantities have been agreed among the EUROfusion
machines AUG, JET-ILW, MAST-U and TCV, allowing future consistent multi-machine
comparisons and scaling laws. The databases will be stored into the IMAS format (ITER
integrated modelling and analysis suite) [1].
The JET-ILW pedestal database contains all the JET-ILW H-mode plasmas with stationary
phases at least 0.5s long (longer than ≈2τE) and with good Thomson scattering data. The
pedestal structure is determined using the pre-ELM profiles of the High Resolution Thomson
Scattering [2] processed as described in [3]. From the point of view of the pedestal structure,
the main parameters stored are: (i) height, (ii) width (iii) position of the maximum gradient,
and (iv) maximum gradient of electron density, temperature and pressure, (v) separatrix
density and (vi) normalized pressure gradient. Pedestal parameters are extracted by fitting the
experimental data with both a mtanh function [4] and a combination of linear functions. In
the JET-ILW database, the two fitting functions produce qualitatively similar results.
Version 1 of the JET-ILW database contains
the discharges till the C37 experimental
campaign (end of 2016) with a total of ≈1200
entries. Figure 1 shows the scatter plot of Teped
and neped in version 1. The database will be
kept up to date.
To complement the experimental data, the
JET-ILW database contains the results of the
peeling-ballooning stability analysis. This was
done by self-consistent runs of ELITE [5] Figure 1. Pedestal temperature and density for the
deuterium unseeded plasmas of the EUROfusion
(using the bootstrap current from the Sauter JET-ILW pedestal database (version 1). Colors
model [6]), which provide the normalized highlight the total input power. Circles: low-δ
pressure gradient αcrit and the temperature Tecrit plasmas (δ<0.25). Triangles: high-δ plasmas
expected by the P-B stability. (δ>0.25).
The present work discusses both the technical aspects of the database (such as parameters
definition and workflow) and the preliminary analysis, with particular emphasis on the
comparison between experimental results and P-B stability predictions.
References
[1] F. Imbeaux et al., Nucl. Fusion 55 (2015) 123006. [4] R. Groebner et al., Nucl. Fusion 41 1789 (2001)
[2] R. Pasqualotto et al., Rev. Sci. Instrum. 75, 3891 (2004). [5] S. Saarelma et al., Phys. Plasmas 22 056115 (2015)
[3] L. Frassinetti et al., Rev. Sci. Instrum. 83, 013506 (2012) [6] O. Sauter et al., Phys. Plasmas 6 2834 (1999)
