Articolo in rivista, 2018, ENG

Analytic stability criteria for edge MHD oscillations in high performance ELM free tokamak regimes

Brunetti, D.; Graves, J. P.; Lazzaro, E.; Mariani, A.; Nowak, S.; Cooper, W. A.; Wahlberg, C.

[ 1 ] CNR, IFP, Via R Cozzi 53, I-20125 Milan, Italy [ 2 ] SPC, CH-1015 Lausanne, Switzerland [ 3 ] Uppsala Univ, Dept Phys & Astron, POB 516, SE-75120 Uppsala, Sweden

A new dispersion relation, and associated stability criteria, is derived for low-n external kink and infernal modes, and is applied to modelling the stability properties of quiescent H-mode like regimes. The analysis, performed in toroidal geometry with large edge pressure gradients associated with a local flattening of the safety factor, includes a pedestal, sheared toroidal rotation and a vacuum region separating the plasma from an ideal metallic wall. The external kink-infernal modes found here exhibit similarities with experimentally observed Edge Harmonic Oscillations.

Nuclear fusion

Keywords

magnetohydrodynamics, tokamak, infernal mode, edge harmonic oscillations

CNR authors

Brunetti Daniele, Lazzaro Enzo, Nowak Silvana

CNR institutes