EFDA-JET-PR(07)04
Controlling the Internal-Transport-Barrier Oscillations in High-Performance Tokamak Plasmas with a Dominant Fraction of Bootstrap Current
It is shown that the relaxation oscillations associated with repetitive Internal-Transport-Barrier (ITB) buildup and collapse in high-performance tokamak plasmas, with Ion-Cyclotron Resonance Heating (ICRH), Neutral-Beam-Injection (NBI), and Lower-Hybrid Current Drive (LHCD), and with a dominant fraction of bootstrap current, can be overcome if the LHCD power is sufficiently high. This result has been obtained using a benchmarked, fully predictive transport model self-consistently iterated with ICRH, NBI, and LHCD modules, the stabilizing role of E×B flow shear being combined with that of reversed magnetic shear in the simulation of ITB dynamics.