Speaker
Description
See the full abstract here:
http://ocs.ciemat.es/EPS2019ABS/pdf/P1.1032.pdf
The tokamak boundary is of central importance for controlled magnetic fusion. It regroups critical technological and scientific challenges that hold the key to achieving and sustaining ignition [1-4]. This includes plasma-surface interaction which submits the material wall to extreme fluence during long pulses, heat and particle transport and exhaust, the physics of edge transport barrier (ETB) formation and edge-localised modes (ELM), to name a few. Here, we use the global, full-f gyrokinetic code ELMFIRE [5] to investigate turbulence at the edge of the FT-2 tokamak. ELMFIRE has been upgraded to include the scrape-off layer in the simulation domain [6,7]. The FT-2 tokamak, which has been extensively studied with ELMFIRE, allows for a detailed study of the edge region thanks to comprehensive diagnostics, in particular a set of Langmuir probes covering most of the poloidal range. Recently, poloidal asymmetries on a flux surface have been reported, both in ELMFIRE in the confined region [8] and in fluid simulations of the edge and SOL [9]. In the current study, a comprehensive investigation of the edge region of dedicated FT-2 discharges is carried out, and compared to ELMFIRE gyrokinetic simulations, to validate the model and provide further insight in the dynamics of turbulence and blobs.
[1] Progress in the ITER Physics Basis, Nucl. Fusion 47 (2007) S1-S414
[2] P. C. Stangeby, The Plasma Boundary of Magnetic Fusion Devices, IOP, 2000
[3] F. Wagner, Plasma Phys. Control. Fusion 49 (2007) B1
[4] F. Ryter et al., Nucl. Fusion 54 (2014) 083003
[5] J. A. Heikkinen et al., J. Comput. Phys. 227 (2008) 55825609
[6] L. Chôné et al., Contrib. Plasma Phys. 58 (2018) 534-539
[7] L. Chôné et al., proceedings of the 45th EPS conference on Plasma Physics (2018)
[8] P. Niskala, PhD Thesis, Aalto University publication series (2018)
[9] B. Zhu et al., Nucl. Fusion 58 (2018) 106039
