Speaker
Alexander James Creely
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P1.1083.pdf
Conferenceonon Plasma
Plasma Physics,
Physics 2018, Prague, Czech Republic P1.1083
Cross-Machine Validation of TGLF and GENE on Alcator C-Mod and
ASDEX Upgrade
A.J. Creely1, N. Cao1, G.D. Conway2, S.J. Freethy1,2, T. Görler2, R.M. McDermott2,
P. Rodriguez-Fernandez1, G. Tardini2, A.E. White1, and the ASDEX Upgrade Team
1
Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, USA
2
Max Planck Institute for Plasma Physics, Garching, Germany
A cross machine validation study of the turbulent transport code TGLF [1] is performed with
experimental data from Alcator C-Mod and ASDEX Upgrade. As validation of gyrokinetic
and gyro-fluid codes becomes more widespread, the importance of validating these codes
across machines becomes increasingly evident, with the ultimate goal of building confidence
in predictions for future machines. In particular, cases for which ion-scale models robustly
under-predict electron heat transport have been identified on Alcator C-Mod, requiring multi-
scale effects to achieve agreement [2], but previously had not been identified on ASDEX
Upgrade. Recent work has also shown that rigorous validation requires comparison of many
experimental parameters to simulations, not only heat fluxes [3, 4]. This study therefore
compares experimental electron and ion heat fluxes, electron temperature fluctuations
(measured with CECE), and perturbative thermal diffusivity (measured with partial sawtooth
heat pulses [5]) from more than 10 L-mode discharges on Alcator C-Mod and ASDEX
Upgrade to the outputs of both ion-scale and multi-scale TGLF simulations, run within the
VITALS framework [6]. A few cases are also compared with the gyrokinetic code GENE [7].
Results to date show good agreement between experiment and multi-scale TGLF on most
discharges from both devices, but disagreement with ion-scale TGLF in some cases on both
devices, though the disagreement is more prevalent on Alcator C-Mod. The dominant
turbulent mode at low wavenumber may, in part, differentiate these cases.
[1] G.M. Staebler et al., Phys. Plasmas 23, 062518 (2016).
[2] N.T. Howard et al., Phys. Plasmas 23, 056109 (2016).
[3] N.T. Howard et al., Plasma Phys. Controlled Fusion 60, 014034 (2018).
[4] C. Holland, Phys. Plasmas 23, 060901 (2016).
[5] A.J. Creely et al., Nucl. Fusion 56, 036003 (2016).
[6] P. Rodriguez-Fernandez et al., Fusion Sci. Technol., Accepted (2017).
[7] F. Jenko et al., Phys. Plasmas 7, 1904 (2000).
This work is supported by the US DOE under grant DE-SC0006419 and by the US DOD under the NDSEG
Fellowship.
