Steady-state operation of tokamaks: key experiments, integrated modelling and technology developments on Tore Supra

Key technological and physics issues related to long pulse operation required for a reactor are now being addressed in Tore Supra. This paper focuses on the experimental results from conditions where all the plasma facing components (PFCs) are actively cooled. Full steady-state plasma quantities as well as stable PFC temperature during pulses exceeding 6 min are reported. Particle balance and D retention in the steady-state are analysed. Physics phenomena related to continuous operation are observed in non-inductively driven plasmas, namely (i) a regime characterized by large sinusoidal oscillations of the central electron temperature, governed by a predator–prey mechanism of non-linear coupling between heat transport and plasma current; (ii) a strong synergy effect between lower hybrid and electron cyclotron waves; (iii) a peaked density profile generated by turbulent inward pinch. Integrated modelling activity at Tore Supra is also reported.