The main magnetic fusion research activities of the French-Euratom Association take place in the “Department of Controlled Fusion Research” (DRFC), at the CEA Cadarache site in Provence. The flagship of the DRFC programme is the Tore Supra tokamak. Its main role is the investigation of steady-state operation and the associated consequences in maintaining a continuous magnetic field.

Power leaving the plasma must be extracted continuously, which means tackling the problem of plasma facing surfaces subject to a permanent bombardement of particles and radiation. For continuous power exhaust, it is necessary to simultaneously control the convective power deposition on the components facing the plasma and the flow of radiated power to all the internal components in direct line of sight of the plasma. Studies of long duration plasma discharges between 1988 and 1999 showed that the power exhaust capacity of the first generation of actively cooled plasma facing components was marginal forĀ  attaining steady-state operation. Therefore, all the internal components in Tore Supra wereupgraded, within the framework of the CIEL (acronym in French for “Internal Components And Limiter”) project, with the objective of giving Tore Supra the capacity to control, in steady state, the injected power (up to 15MW of convected power with a maximum flux of 10MW/m2, and 10MW of radiated power with a flux of 1MW/m2, continuously). The design, done in 1992, was aimed at simplifying the manufacturing processes and a series of mockups were realised and tested before the elements could be ordered in 1997, after the project obtained preferential support by the EU Commission in 1996.

. High Magnetic field: 4T

. superconducting toroidal field coils cooled by super-fluid helium at a temperature of 1.8K

. 1988 to 1999: study of physics and technology of a hot core plasma in steady-state conditions – an essential item towards a reactor.

. Optimisation and sustainment of the plasma current and pressure distributions over long times are achieved by means of strong HF power at frequencies absorbed by the plasma: “lower hybrid resonance” at 3.7GHz. (6MW of microwave power) and “ion cyclotron resonance” at 42-63MHz (9MW of radio-frequency power).